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Dunn CM, Kameishi S, Parker T, Cho YK, Song SU, Grainger DW, Okano T. Cellular Interactions in Cell Sheets Enhance Mesenchymal Stromal Cell Immunomodulatory Properties. Tissue Eng Part A 2023; 29:594-603. [PMID: 37847176 DOI: 10.1089/ten.tea.2023.0059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023] Open
Abstract
Immune-related applications of mesenchymal stromal cells (MSCs) in cell therapy seek to exploit immunomodulatory paracrine signaling pathways to reduce inflammation. A key MSC therapeutic challenge is reducing patient outcome variabilities attributed to insufficient engraftment/retention of injected heterogenous MSCs. To address this, we propose directly transplantable human single-cell-derived clonal bone marrow MSC (hcBMSC) sheets. Cell sheet technology is a scaffold-free tissue engineering strategy enabling scalable production of highly engraftable cell constructs retaining endogenous cell-cell and cell-matrix interactions, important to cell function. cBMSCs, as unique MSC subset populations, facilitate rational selection of therapeutically relevant MSC clones from donors. Here, we combine human cBMSCs with cell sheet technology, demonstrating cell sheet fabrication as a method to significantly upregulate expression of immunomodulatory molecules interleukin (IL)-10, indoleamine 2,3-dioxygenase (IDO-1), and prostaglandin E synthase 2 (PTGES2) across GMP-grade hcBMSC lines and whole human bone marrow-derived MSCs compared to respective conventional cell suspensions. When treated with carbenoxolone, a gap junction inhibitor, cell sheets downregulate IL-10 and IDO-1 expression, implicating functional roles for intercellular sheet interactions. Beyond producing directly transferable multicellular hcBMSC constructs, cell sheet technology amplifies hcBMSC expression of immunomodulatory factors important to therapeutic action. In addition, this work demonstrates the importance of cell-cell interactions as a tissue engineering design criterion to enhance consistent MSC functions.
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Affiliation(s)
- Celia M Dunn
- Cell Sheet Tissue Engineering Center (CSTEC), Department of Molecular Pharmaceutics, University of Utah, Salt Lake City, Utah, USA
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah, USA
| | - Sumako Kameishi
- Cell Sheet Tissue Engineering Center (CSTEC), Department of Molecular Pharmaceutics, University of Utah, Salt Lake City, Utah, USA
| | - Tavie Parker
- Cell Sheet Tissue Engineering Center (CSTEC), Department of Molecular Pharmaceutics, University of Utah, Salt Lake City, Utah, USA
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah, USA
| | | | - Sun U Song
- SCM Lifescience Co., Ltd., Incheon, Republic of Korea
| | - David W Grainger
- Cell Sheet Tissue Engineering Center (CSTEC), Department of Molecular Pharmaceutics, University of Utah, Salt Lake City, Utah, USA
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah, USA
| | - Teruo Okano
- Cell Sheet Tissue Engineering Center (CSTEC), Department of Molecular Pharmaceutics, University of Utah, Salt Lake City, Utah, USA
- Institute for Advanced Biomedical Sciences, Tokyo Women's Medical University, Tokyo, Japan
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2
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Chua JW, Thangaveloo M, Lim DXE, Madden LE, Phillips ARJ, Becker DL. Connexin43 in Post-Surgical Peritoneal Adhesion Formation. Life (Basel) 2022; 12:1734. [PMID: 36362888 PMCID: PMC9697983 DOI: 10.3390/life12111734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/15/2022] [Accepted: 10/26/2022] [Indexed: 09/10/2024] Open
Abstract
OBJECTIVE Post-surgical peritoneal adhesions are a serious problem for the quality of life and fertility. Yet there are no effective ways of preventing their occurrence. The gap junction protein Cx43 is known to be involved in fibrosis in several different organs and disease conditions often associated with inflammation. Here we examined the Cx43 dynamic expression in an ischemic button model of surgical adhesions. METHODS Using the mouse ischemic button model, Cx43 antisense was delivered in Pluronic gel to attenuate Cx43 expression. The severity of button formation and immunofluorescence analysis of Cx43 and TGF-β1 were performed. The concentration of tissue plasminogen activator via ELISA was also performed. RESULTS As early as 6 h after button formation, the Cx43 levels were elevated in and around the button and some weak adhesions were formed. By 24 h Cx43 levels had increased further and adhesions were more defined. At 7 days the adhesions were much more robust, opaque, and vascularized, requiring blunt or sharp dissection to break them. Cx43 antisense attenuated its upregulation and, reduced the number and severity of adhesions that formed. CONCLUSION Targeting Cx43 after surgical procedures may be a potential therapeutic strategy for preventing adhesion formation or at least reducing their severity.
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Affiliation(s)
- Jia Wang Chua
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore 308232, Singapore
- Skin Research Institute Singapore, Singapore 308232, Singapore
| | - Moogaambikai Thangaveloo
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore 308232, Singapore
- Skin Research Institute Singapore, Singapore 308232, Singapore
| | - Debbie Xiu En Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore 308232, Singapore
- Skin Research Institute Singapore, Singapore 308232, Singapore
| | - Leigh E. Madden
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore 308232, Singapore
- Skin Research Institute Singapore, Singapore 308232, Singapore
| | | | - David L. Becker
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore 308232, Singapore
- Skin Research Institute Singapore, Singapore 308232, Singapore
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3
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Schulman CI, Namias N, Pizano L, Rodriguez-Menocal L, Aickara D, Guzman W, Candanedo A, Maranda E, Beirn A, Badiavas EV. The effect of mesenchymal stem cells improves the healing of burn wounds: a phase 1 dose-escalation clinical trial. Scars Burn Heal 2022; 8:20595131211070783. [PMID: 35781931 PMCID: PMC9247372 DOI: 10.1177/20595131211070783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Background Stem cell therapy holds promise to improve healing and stimulate tissue
regeneration after burn injury. Preclinical evidence has supported this;
however, clinical studies are lacking. We examined the application of bone
marrow-derived mesenchymal stem cells (BM-MSC) to deep second-degree burn
injuries using a two-dose escalation protocol. Methods Ten individuals aged 18 years or older with deep second-degree burn wounds
were enrolled. The first five patients were administered 2.5 × 10³
BM-MSC/cm2 to their wounds. After safety of the initial dose
level was assessed, a second group of five patients was treated with a
higher concentration of 5 × 10³ allogeneic BM-MSC/cm2. Safety was
assessed clinically and by evaluating cytokine levels in mixed recipient
lymphocyte/donor BM-MSC reactions (INFγ, IL-10 and TNFα). At each visit, we
performed wound measurements and assessed wounds using a Patient and
Observer Scar Assessment Scale (POSAS). Results All patients responded well to treatment, with 100% closure of wounds and
minimal clinical evidence of fibrosis. No adverse reactions or evidence of
rejection were observed for both dose levels. Patients receiving the first
dose concentration had a wound closure rate of 3.64 cm2/day.
Patients receiving the second dose concentration demonstrated a wound
closure rate of 10.47 cm2/day. The difference in healing rates
between the two groups was not found to be statistically significant
(P = 0.17). Conclusion BM-MSC appear beneficial in optimising wound healing in patients with deep
second-degree burn wounds. Adverse outcomes were not observed when
administering multiple doses of allogeneic BM-MSC. Lay Summary Thermal injuries are a significant source of morbidity and mortality,
constituting 5%–20% of all injuries and 4% of all deaths. Despite overall
improvements in the management of acutely burned patients, morbidities
associated with deeper burn injuries remain commonplace. Burn patients are
too often left with significant tissue loss, scarring and contractions
leading to physical loss of function and long-lasting psychological and
emotional impacts. In previous studies, we have demonstrated the safety and efficacy of
administering bone marrow-derived mesenchymal stem cells (BM-MSC) to chronic
wounds with substantial improvement in healing and evidence of tissue
regeneration. In this report, we have examined the application of BM-MSC to
deep second-degree burn injuries in patients. The aim of the present phase I/II clinical trial was to examine the safety
and efficacy of administering allogeneic BM-MSC to deep second-degree burns.
We utilised two different dose levels at concentrations 2.5 × 103
and 5 × 103 cells/cm2. Patients with deep
second-degree burn wounds up to 20% of the total body surface area were
eligible for treatment. Allogeneic BM-MSC were applied to burn wounds
topically or by injection under transparent film dressing <7 days after
injury. Patients were followed for at least six months after treatment. Using two dose levels allowed us to gain preliminary information as to
whether different amounts of BM-MSC administered to burn wounds will result
in significant differences in safety/ clinical response. Once the safety and
dose-response analysis were completed, we evaluated the efficacy of
allogeneic stem cell therapy in the treatment of deep second-degree burn
wounds. In this study, we examined the role of allogeneic BM-MSC treatment in
patients with deep second-degree burn injuries, in a dose-dependent manner.
No significant related adverse events were reported. Safety was evaluated
both clinically and by laboratory-based methods. Efficacy was assessed
clinically through evidence of re-pigmentation, hair follicle restoration
and regenerative change. While these findings are encouraging, more studies
will be needed to better establish the benefit of BM-MSC in the treatment of
burn injuries.
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Affiliation(s)
- Carl I Schulman
- Department of Surgery, Ryder Trauma Center, University of Miami School of Medicine, Miami, FL, USA
| | - Nicholas Namias
- Department of Surgery, Ryder Trauma Center, University of Miami School of Medicine, Miami, FL, USA
| | - Louis Pizano
- Department of Surgery, Ryder Trauma Center, University of Miami School of Medicine, Miami, FL, USA
| | - Luis Rodriguez-Menocal
- Department of Dermatology and Cutaneous Surgery. Leonard M Miller School of Medicine, University of Miami, Interdisciplinary Stem Cell Institute, Miami, FL, USA
| | - Divya Aickara
- Department of Dermatology and Cutaneous Surgery. Leonard M Miller School of Medicine, University of Miami, Interdisciplinary Stem Cell Institute, Miami, FL, USA
| | - Wellington Guzman
- Department of Surgery, Ryder Trauma Center, University of Miami School of Medicine, Miami, FL, USA
| | - Ambar Candanedo
- Department of Surgery, Ryder Trauma Center, University of Miami School of Medicine, Miami, FL, USA
| | - Eric Maranda
- Department of Dermatology and Cutaneous Surgery. Leonard M Miller School of Medicine, University of Miami, Interdisciplinary Stem Cell Institute, Miami, FL, USA
| | - Audrey Beirn
- Department of Dermatology and Cutaneous Surgery. Leonard M Miller School of Medicine, University of Miami, Interdisciplinary Stem Cell Institute, Miami, FL, USA
| | - Evangelos V Badiavas
- Department of Dermatology and Cutaneous Surgery. Leonard M Miller School of Medicine, University of Miami, Interdisciplinary Stem Cell Institute, Miami, FL, USA
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Tittarelli A. Connexin channels modulation in pathophysiology and treatment of immune and inflammatory disorders. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166258. [PMID: 34450245 DOI: 10.1016/j.bbadis.2021.166258] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/28/2021] [Accepted: 08/19/2021] [Indexed: 12/16/2022]
Abstract
Connexin-mediated intercellular communication mechanisms include bidirectional cell-to-cell coupling by gap junctions and release/influx of molecules by hemichannels. These intercellular communications have relevant roles in numerous immune system activities. Here, we review the current knowledge about the function of connexin channels, mainly those formed by connexin-43, on immunity and inflammation. Focusing on those evidence that support the design and development of therapeutic tools to modulate connexin expression and/or channel activities with treatment potential for infections, wounds, cancer, and other inflammatory conditions.
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Affiliation(s)
- Andrés Tittarelli
- Programa Institucional de Fomento a la Investigación, Desarrollo e Innovación, Universidad Tecnológica Metropolitana, Santiago 8940577, Chile.
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Haralambieva IH, Eberhard KG, Ovsyannikova IG, Grill DE, Schaid DJ, Kennedy RB, Poland GA. Transcriptional signatures associated with rubella virus-specific humoral immunity after a third dose of MMR vaccine in women of childbearing age. Eur J Immunol 2021; 51:1824-1838. [PMID: 33818775 PMCID: PMC9841595 DOI: 10.1002/eji.202049054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 03/03/2021] [Accepted: 12/17/2020] [Indexed: 01/19/2023]
Abstract
Multiple factors linked to host genetics/inherent biology play a role in interindividual variability in immune response outcomes after rubella vaccination. In order to identify these factors, we conducted a study of rubella-specific humoral immunity before (Baseline) and after (Day 28) a third dose of MMR-II vaccine in a cohort of 109 women of childbearing age. We performed mRNA-Seq profiling of PBMCs after rubella virus in vitro stimulation to delineate genes associated with post-vaccination rubella humoral immunity and to define genes mediating the association between prior immune response status (high or low antibody) and subsequent immune response outcome. Our study identified novel genes that mediated the association between prior immune response and neutralizing antibody titer after a third MMR vaccine dose. These genes included the following: CDC34; CSNK1D; APOBEC3F; RAD18; AAAS; SLC37A1; FAS; and JAK2. The encoded proteins are involved in innate antiviral response, IFN/cytokine signaling, B cell repertoire generation, the clonal selection of B lymphocytes in germinal centers, and somatic hypermutation/antibody affinity maturation to promote optimal antigen-specific B cell immune function. These data advance our understanding of how subjects' prior immune status and/or genetic propensity to respond to rubella/MMR vaccination ultimately affects innate immunity and humoral immune outcomes after vaccination.
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Affiliation(s)
| | | | | | - Diane E. Grill
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Daniel J. Schaid
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Richard B. Kennedy
- Mayo Clinic Vaccine Research Group, Mayo Clinic, Rochester, MN 55905, USA
| | - Gregory A. Poland
- Mayo Clinic Vaccine Research Group, Mayo Clinic, Rochester, MN 55905, USA
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6
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Antagonistic Functions of Connexin 43 during the Development of Primary or Secondary Bone Tumors. Biomolecules 2020; 10:biom10091240. [PMID: 32859065 PMCID: PMC7565206 DOI: 10.3390/biom10091240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/20/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022] Open
Abstract
Despite research and clinical advances during recent decades, bone cancers remain a leading cause of death worldwide. There is a low survival rate for patients with primary bone tumors such as osteosarcoma and Ewing’s sarcoma or secondary bone tumors such as bone metastases from prostate carcinoma. Gap junctions are specialized plasma membrane structures consisting of transmembrane channels that directly link the cytoplasm of adjacent cells, thereby enabling the direct exchange of small signaling molecules between cells. Discoveries of human genetic disorders due to genetic mutations in gap junction proteins (connexins) and experimental data using connexin knockout mice have provided significant evidence that gap-junctional intercellular communication (Gj) is crucial for tissue function. Thus, the dysfunction of Gj may be responsible for the development of some diseases. Gj is thus a main mechanism for tumor cells to communicate with other tumor cells and their surrounding microenvironment to survive and proliferate. If it is well accepted that a low level of connexin expression favors cancer cell proliferation and therefore primary tumor development, more evidence is suggesting that a high level of connexin expression stimulates various cellular process such as intravasation, extravasation, or migration of metastatic cells. If so, connexin expression would facilitate secondary tumor dissemination. This paper discusses evidence that suggests that connexin 43 plays an antagonistic role in the development of primary bone tumors as a tumor suppressor and secondary bone tumors as a tumor promoter.
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7
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Singh AK, Cancelas JA. Gap Junctions in the Bone Marrow Lympho-Hematopoietic Stem Cell Niche, Leukemia Progression, and Chemoresistance. Int J Mol Sci 2020; 21:E796. [PMID: 31991829 PMCID: PMC7038046 DOI: 10.3390/ijms21030796] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/19/2020] [Accepted: 01/23/2020] [Indexed: 12/15/2022] Open
Abstract
Abstract: The crosstalk between hematopoietic stem cells (HSC) and bone marrow (BM) microenvironment is critical for homeostasis and hematopoietic regeneration in response to blood formation emergencies after injury, and has been associated with leukemia transformation and progression. Intercellular signals by the BM stromal cells in the form of cell-bound or secreted factors, or by physical interaction, regulate HSC localization, maintenance, and differentiation within increasingly defined BM HSC niches. Gap junctions (GJ) are comprised of arrays of membrane embedded channels formed by connexin proteins, and control crucial signaling functions, including the transfer of ions, small metabolites, and organelles to adjacent cells which affect intracellular mechanisms of signaling and autophagy. This review will discuss the role of GJ in both normal and leukemic hematopoiesis, and highlight some of the most novel approaches that may improve the efficacy of cytotoxic drugs. Connexin GJ channels exert both cell-intrinsic and cell-extrinsic effects on HSC and BM stromal cells, involved in regenerative hematopoiesis after myelosuppression, and represent an alternative system of cell communication through a combination of electrical and metabolic coupling as well as organelle transfer in the HSC niche. GJ intercellular communication (GJIC) in the HSC niche improves cellular bioenergetics, and rejuvenates damaged recipient cells. Unfortunately, they can also support leukemia proliferation and survival by creating leukemic niches that provide GJIC dependent energy sources and facilitate chemoresistance and relapse. The emergence of new strategies to disrupt self-reinforcing malignant niches and intercellular organelle exchange in leukemic niches, while at the same time conserving normal hematopoietic GJIC function, could synergize the effect of chemotherapy drugs in eradicating minimal residual disease. An improved understanding of the molecular basis of connexin regulation in normal and leukemic hematopoiesis is warranted for the re-establishment of normal hematopoiesis after chemotherapy.
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Affiliation(s)
- Abhishek K. Singh
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229, USA;
- Hoxworth Blood Center, University of Cincinnati Academic Health Center, 3333 Burnet Ave., Cincinnati, OH 45229, USA
| | - Jose A. Cancelas
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229, USA;
- Hoxworth Blood Center, University of Cincinnati Academic Health Center, 3333 Burnet Ave., Cincinnati, OH 45229, USA
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8
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Huang Y, Mao Z, Zhang X, Yang X, Sawada N, Takeda M, Yao J. Connexin43 Is Required for the Effective Activation of Spleen Cells and Immunoglobulin Production. Int J Mol Sci 2019; 20:ijms20225789. [PMID: 31752090 PMCID: PMC6888161 DOI: 10.3390/ijms20225789] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/05/2019] [Accepted: 11/15/2019] [Indexed: 02/07/2023] Open
Abstract
Gap junctions (Gjs), formed by specific protein termed connexins (Cxs), regulate many important cellular processes in cellular immunity. However, little is known about their effects on humoral immunity. Here we tested whether and how Gj protein connexin43 (Cx43) affected antibody production in spleen cells. Detection of IgG in mouse tissues and serum revealed that wild-type (Cx43+/+) mouse had a significantly higher level of IgG than Cx43 heterozygous (Cx43+/−) mouse. Consistently, spleen cells from Cx43+/+ mouse produced more IgG under both basal and lipopolysaccharide (LPS)-stimulated conditions. Further analysis showed that LPS induced a more dramatic activation of ERK and cell proliferation in Cx43+/+ spleen cells, which was associated with a higher pro-oxidative state, as indicated by the increased NADPH oxidase 2 (NOX2), TXNIP, p38 activation and protein carbonylation. In support of a role of the oxidative state in the control of lymphocyte activation, exposure of spleen cells to exogenous superoxide induced Cx43 expression, p38 activation and IgG production. On the contrary, inhibition of NOX attenuated the effects of LPS. Collectively, our study characterized Cx43 as a novel molecule involved in the control of spleen cell activation and IgG production. Targeting Cx43 could be developed to treat certain antibody-related immune diseases.
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Affiliation(s)
- Yanru Huang
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.H.); (Z.M.); (X.Z.); (X.Y.)
| | - Zhimin Mao
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.H.); (Z.M.); (X.Z.); (X.Y.)
| | - Xiling Zhang
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.H.); (Z.M.); (X.Z.); (X.Y.)
| | - Xiawen Yang
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.H.); (Z.M.); (X.Z.); (X.Y.)
| | - Norifumi Sawada
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (N.S.); (M.T.)
| | - Masayuki Takeda
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (N.S.); (M.T.)
| | - Jian Yao
- Division of Molecular Signaling, Department of the Advanced Biomedical Research, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.H.); (Z.M.); (X.Z.); (X.Y.)
- Correspondence: ; Tel.: +81-55-273-8074
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Hofmann F, Navarrete M, Álvarez J, Guerrero I, Gleisner MA, Tittarelli A, Salazar-Onfray F. Cx43-Gap Junctions Accumulate at the Cytotoxic Immunological Synapse Enabling Cytotoxic T Lymphocyte Melanoma Cell Killing. Int J Mol Sci 2019; 20:ijms20184509. [PMID: 31547237 PMCID: PMC6769613 DOI: 10.3390/ijms20184509] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/03/2019] [Accepted: 09/06/2019] [Indexed: 12/17/2022] Open
Abstract
Upon tumor antigen recognition, cytotoxic T lymphocytes (CTLs) and target cells form specialized supramolecular structures, called cytotoxic immunological synapses, which are required for polarized delivery of cytotoxic granules. In previous reports, we described the accumulation of connexin 43 (Cx43)-formed gap junctions (GJs) at natural killer (NK) cell–tumor cell cytotoxic immunological synapse. In this report, we demonstrate the functional role of Cx43-GJs at the cytotoxic immunological synapse established between CTLs and melanoma cells during cytotoxicity. Using confocal microscopy, we evaluated Cx43 polarization to the contact site between CTLs isolated from pMEL-1 mice and B16F10 melanoma cells. We knocked down Cx43 expression in B16F10 cells and evaluated its role in the formation of functional GJs and the cytotoxic activity of CTLs, by calcein transfer and granzyme B activity assays, respectively. We found that Cx43 localizes at CTL/B16F10 intercellular contact sites via an antigen-dependent process. We also found that pMEL-1 CTLs but not wild-type naïve CD8+ T cells established functional GJs with B16F10 cells. Interestingly, we observed that Cx43-GJs were required for an efficient granzyme B activity in target B16F10 cells. Using an HLA-A2-restricted/MART-1-specific CD8+ T-cell clone, we confirmed these observations in human cells. Our results suggest that Cx43-channels are relevant components of cytotoxic immunological synapses and potentiate CTL-mediated tumor cell killing.
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Affiliation(s)
- Francisca Hofmann
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
| | - Mariela Navarrete
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
| | - Javiera Álvarez
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
| | - Israel Guerrero
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
| | - María Alejandra Gleisner
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
| | - Andrés Tittarelli
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
| | - Flavio Salazar-Onfray
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
- Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
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10
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Ni X, Zhang L, Ma X, Shan LY, Li L, Si JQ, Li XZ, Zhang YY, Ma KT. β‑estradiol alleviates hypertension‑ and concanavalin A‑mediated inflammatory responses via modulation of connexins in peripheral blood lymphocytes. Mol Med Rep 2019; 19:3743-3755. [PMID: 30896818 PMCID: PMC6471871 DOI: 10.3892/mmr.2019.10037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 03/08/2019] [Indexed: 12/24/2022] Open
Abstract
Gap junctions (GJs) formed by connexins (Cxs) in T lymphocytes have been reported to have important roles in the T lymphocyte-driven inflammatory response and hypertension-mediated inflammation. Estrogen has a protective effect on cardiovascular diseases, including hypertension and it attenuates excessive inflammatory responses in certain autoimmune diseases. However, the mechanisms involved in regulating the pro-inflammatory response are complex and poorly understood. The current study investigated whether β-estradiol suppresses hypertension and pro-inflammatory stimuli-mediated inflammatory responses by regulating Cxs and Cx-mediated GJs in peripheral blood lymphocytes. Male, 16-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) rats were randomly divided into the following three groups: WKY rats, vehicle (saline)-treated SHRs, and β-estradiol (20 µg/kg/day)-treated SHRs. β-estradiol was administered subcutaneously for 5 weeks. Hematoxylin and eosin staining was performed to evaluate target organ injury. Flow cytometry and ELISA were used to measure the populations of T lymphocyte subtypes in the peripheral blood, and expression of Cx40/Cx43 in T cell subtypes, and pro-inflammation cytokines levels, respectively. ELISA, a dye transfer technique, immunofluorescence and immunoblotting were used to analyze the effect of β-estradiol on pro-inflammatory cytokine secretion, Cx-mediated GJs and the expression of Cxs in concanavalin A (Con A)-stimulated peripheral blood lymphocytes isolated from WKY rat. β-estradiol significantly decreased blood pressure and inhibited hypertension-induced target organ injury in SHRs. Additionally, β-estradiol treatment significantly improved the immune homeostasis of SHRs, as demonstrated by the decreased percentage of cluster of differentiation (CD)4+/CD8+ T-cell subset ratio, reduced serum levels of pro-inflammatory cytokines and increased the percentage of CD4+CD25+ T cells. β-estradiol also markedly reduced the expression of Cx40/Cx43 in T lymphocytes from SHRs. In vitro, β-estradiol significantly suppressed the production of pro-inflammatory cytokines, reduced communication via Cx-mediated gap junctions and decreased the expression of Cx40/Cx43 in Con A-stimulated lymphocytes. These results indicate that β-estradiol attenuates inflammation and end organ damage in hypertension, which may be partially mediated via downregulated expression of Cxs and reduced function of Cx-mediated GJ.
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Affiliation(s)
- Xin Ni
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Liang Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Xin Ma
- Department of Anesthesiology, First Affiliated Hospital, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Li-Ya Shan
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Li Li
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Jun-Qiang Si
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Xin-Zhi Li
- Department of Pathophysiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - You-Yi Zhang
- Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Ke-Tao Ma
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
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11
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Rodríguez-Alba JC, Abrego-Peredo A, Gallardo-Hernández C, Pérez-Lara J, Santiago-Cruz JW, Jiang JW, Espinosa E. HIV Disease Progression: Overexpression of the Ectoenzyme CD38 as a Contributory Factor? Bioessays 2019; 41:e1800128. [PMID: 30537007 PMCID: PMC6545924 DOI: 10.1002/bies.201800128] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 11/02/2018] [Indexed: 12/16/2022]
Abstract
Despite abundant evidence associating CD38 overexpression and CD4 T cell depletion in HIV infection, no causal relation has been investigated. To address this issue, a series of mechanisms are proposed, supported by evidence from different fields, by which CD38 overexpression can facilitate CD4 T cell depletion in HIV infection. According to this model, increased catalytic activity of CD38 may reduce CD4 T cells' cytoplasmic nicotin-amide adenine dinucleotide (NAD), leading to a chronic Warburg effect. This will reduce mitochondrial function. Simultaneously, CD38's catalytic products ADPR and cADPR may be transported to the cytoplasm, where they can activate calcium channels and increase cytoplasmic Ca2+ concentrations, further altering mitochondrial integrity. These mechanisms will decrease the viability and regenerative capacity of CD4 T cells. These hypotheses can be tested experimentally, and might reveal novel therapeutic targets. Also see the video abstract here https://youtu.be/k1LTyiTKPKs.
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Affiliation(s)
- J. C. Rodríguez-Alba
- Flow Cytometry Core Facility, Instituto de Ciencias de la Salud, Universidad Veracruzana, Xalapa, Mexico
| | - A. Abrego-Peredo
- Doctorado en Ciencias de la Salud, Instituto de Ciencias de la Salud, Universidad Veracruzana, Xalapa, Mexico
| | - C. Gallardo-Hernández
- Doctorado en Ciencias de la Salud, Instituto de Ciencias de la Salud, Universidad Veracruzana, Xalapa, Mexico
| | - J. Pérez-Lara
- Doctorado en Ciencias de la Salud, Instituto de Ciencias de la Salud, Universidad Veracruzana, Xalapa, Mexico
| | - J. W. Santiago-Cruz
- Maestría en Ciencias de la Salud, Instituto de Ciencias de la Salud, Universidad Veracruzana, Xalapa, Mexico
| | - J., W. Jiang
- Department of Microbiology and Immunology, and Division of Infectious Diseases, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA, 29425
| | - E. Espinosa
- Laboratory of Integrative Immunology, National Institute of Respiratory Diseases (INER), Mexico City, Mexico
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12
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Hughes BR, Mirbagheri M, Waldman SD, Hwang DK. Direct cell-cell communication with three-dimensional cell morphology on wrinkled microposts. Acta Biomater 2018; 78:89-97. [PMID: 30092377 DOI: 10.1016/j.actbio.2018.07.053] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/23/2018] [Accepted: 07/29/2018] [Indexed: 01/09/2023]
Abstract
Cell-cell communication plays a critical role in a myriad of processes, such as homeostasis, angiogenesis, and carcinogenesis, in multi-cellular organisms. Monolayer cell models have notably improved our understanding of cellular interactions. However, the cultured cells on the planar surfaces adopt a two-dimensional morphology, which poorly imitates cellular organization in vivo, providing physiologically-irrelevant cell responses. Non-planar surfaces comprising various patterns have demonstrated great abilities in directing cellular growth and producing different cell morphologies. In recent years, a few topographical substrates have provided valuable information about cell-cell signalling, however, none of these studies have reported a three-dimensional (3D) cell morphology. Here, we introduce a structurally tunable topographical platform that can maintain cell coupling while inducing a true 3D cell morphology. Optical imaging and fluorescence recovery after photobleaching are used to illustrate these capabilities. Our analyses suggest that the intercellular signalling on the present platform, which we propose is mainly through gap junctions, is comparable to that in natural tissue. STATEMENT OF SIGNIFICANCE A better understanding of direct cellular communication can help treating neurological diseases and cancers, which may be caused by dysfunctional intercellular signaling. To investigate cell-cell contact, cells are conventionally plated onto planar surfaces, where they flatten and adopt a two-dimensional cell morphology. These unrealistic models are physiologically-irrelevant since cells exhibit a three-dimensional (3D) shape in the body. Therefore, porous scaffolds and topographical surfaces, capable of inducing various cell morphologies, have been introduced, in which the latter is more desirable for sample imaging and screening. However, the few non-planar substrates used to study cell coupling have not produced a 3D cell shape. Here, we present a tunable culture platform that can control direct cell-cell communication while maintaining true 3D cell morphologies.
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13
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Ni X, Li XZ, Fan ZR, Wang A, Zhang HC, Zhang L, LI L, Si JQ, Ma KT. Increased expression and functionality of the gap junction in peripheral blood lymphocytes is associated with hypertension-mediated inflammation in spontaneously hypertensive rats. Cell Mol Biol Lett 2018; 23:40. [PMID: 30151015 PMCID: PMC6102908 DOI: 10.1186/s11658-018-0106-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 08/06/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Imbalances in circulating T lymphocytes play critical roles in the pathogenesis of hypertension-mediated inflammation. Connexins (Cxs) in immune cells are involved in the maintenance of homeostasis of T lymphocytes. However, the association between Cxs in peripheral blood T lymphocytes and hypertension-mediated inflammation remains unknown. This study was designed to investigate the role of Cxs in T lymphocytes in hypertension-mediated inflammation in spontaneously hypertensive rats (SHRs). METHODS The systolic blood pressure (SBP) in Wistar-Kyoto (WKY) rats and SHRs was monitored using the tail-cuff method. The serum cytokine level was determined using ELISA. The proportions of different T-lymphocyte subtypes in the peripheral blood, the expressions of Cx40/Cx43 in the T-cell subtypes, and the gap junctional intracellular communication (GJIC) of peripheral blood lymphocytes were measured using flow cytometry (FC). The accumulations of Cx40/Cx43 at the plasma membrane and/or in the cytoplasm were determined using immunofluorescence staining. The in vitro mRNA levels of cytokines and GJIC in the peripheral blood lymphocytes were respectively examined using real-time PCR and FC after treatment with Gap27 and/or concanavalin A (Con A). RESULTS The percentage of CD4+ T cells and the CD4+/CD8+ ratio were high, and the accumulation or expressions of Cx40/Cx43 in the peripheral blood lymphocytes in SHRs were higher than in those of WKY rats. The percentage of CD8+ and CD4+CD25+ T cells was lower in SHRs. The serum levels of IL-2, IL-4 and IL-6 from SHRs were higher than those from WKY rats, and the serum levels of IL-2 and IL-6 positively correlated with the expression of Cx40/Cx43 in the peripheral blood T lymphocytes from SHRs. The peripheral blood lymphocytes of SHRs exhibited enhanced GJIC. Cx43-based channel inhibition, which was mediated by Gap27, remarkably reduced GJIC in lymphocytes, and suppressed IL-2 and IL-6 mRNA expressions in Con A stimulated peripheral blood lymphocytes. CONCLUSIONS Our data suggest that Cxs may be involved in the regulation of T-lymphocyte homeostasis and the production of cytokines. A clear association was found between alterations in Cxs expression or in Cx43-based GJIC and hypertension-mediated inflammation.
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Affiliation(s)
- Xin Ni
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Xin-zhi Li
- Department of Pathophysiology, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Zhi-ru Fan
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Ai Wang
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Hai-chao Zhang
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Liang Zhang
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Li LI
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Jun-qiang Si
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
| | - Ke-tao Ma
- Department of Physiology, Medical College of Shihezi University, 59 North 2nd Road, Shihezi, Xinjiang 832002 People’s Republic of China
- Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang China
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14
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Willebrords J, Maes M, Crespo Yanguas S, Vinken M. Inhibitors of connexin and pannexin channels as potential therapeutics. Pharmacol Ther 2017; 180:144-160. [PMID: 28720428 PMCID: PMC5802387 DOI: 10.1016/j.pharmthera.2017.07.001] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
While gap junctions support the exchange of a number of molecules between neighboring cells, connexin hemichannels provide communication between the cytosol and the extracellular environment of an individual cell. The latter equally holds true for channels composed of pannexin proteins, which display an architecture reminiscent of connexin hemichannels. In physiological conditions, gap junctions are usually open, while connexin hemichannels and, to a lesser extent, pannexin channels are typically closed, yet they can be activated by a number of pathological triggers. Several agents are available to inhibit channels built up by connexin and pannexin proteins, including alcoholic substances, glycyrrhetinic acid, anesthetics and fatty acids. These compounds not always strictly distinguish between gap junctions, connexin hemichannels and pannexin channels, and may have effects on other targets as well. An exception lies with mimetic peptides, which reproduce specific amino acid sequences in connexin or pannexin primary protein structure. In this paper, a state-of-the-art overview is provided on inhibitors of cellular channels consisting of connexins and pannexins with specific focus on their mode-of-action and therapeutic potential.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium.
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15
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Zhang HC, Zhang ZS, Zhang L, Wang A, Zhu H, Li L, Si JQ, Li XZ, Ma KT. Connexin 43 in splenic lymphocytes is involved in the regulation of CD4+CD25+ T lymphocyte proliferation and cytokine production in hypertensive inflammation. Int J Mol Med 2017; 41:13-24. [PMID: 29115377 PMCID: PMC5746298 DOI: 10.3892/ijmm.2017.3201] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 09/27/2017] [Indexed: 12/11/2022] Open
Abstract
Chronic inflammation promotes the development of hypertension and is associated with increased T cell infiltration and cytokine production in impaired organs. Gap junction protein connexin 43 (Cx43), is ubiquitously expressed in immune cells and plays an important role in T cell proliferation and activation, and cytokine production. However, the correlation between Cx43 in T cells and the hypertensive inflammatory response remains unknown. Thus, in this study, we wished to examine this correlation. First, our results revealed that hypertension caused significant thickening of the vascular wall, inflammatory cell infiltration into part of the renal interstitium and glomerular atrophy, and it increased the tubular damage scores in the kidneys of spontaneously hypertensive rats (SHRs). Moreover, the SHRs exhibited stenosis in the central artery wall of the spleen with increased serum levels of interleukin (IL)-2 and IL-6 compared with normotensive Wistar-Kyoto (WKY) rats. The spleens of the SHRs exhibited a significantly decreased percentage of CD4+CD25+ (Treg) T cells. However, the percentages of CD3+, CD4+ and CD8+ T cell and the levels of CD4+Cx43 and CD8+Cx43 did not differ significantly between the SHRs and WKY rats. In cultured lymphocytes from the SHRs and WKY rats, low percentages of Treg cells and reduced cytokine (IL-2 and IL-6) mRNA expression levels were observed in the lymphocytes obtained from the SHRs and WKY rats treated with the connexin blocker, Gap27, or concanavalin A (ConA) plus Gap27. The effects of ConA and Gap27 differed between the SHRs and WKY rats. On the whole, our findings demonstrate that the splenic Treg cell-mediated suppression in SHRs may be involved in hypertensive inflammatory responses. Cx43 in the gap junctional channel may regulate lymphocyte activation and inflammatory cytokine production.
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Affiliation(s)
- Hai-Chao Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Zhong-Shuang Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Liang Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Ai Wang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - He Zhu
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Li Li
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Jun-Qiang Si
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Xin-Zhi Li
- The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
| | - Ke-Tao Ma
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832000, P.R. China
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16
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Ni X, Wang A, Zhang L, Shan LY, Zhang HC, Li L, Si JQ, Luo J, Li XZ, Ma KT. Up-regulation of gap junction in peripheral blood T lymphocytes contributes to the inflammatory response in essential hypertension. PLoS One 2017; 12:e0184773. [PMID: 28910394 PMCID: PMC5599050 DOI: 10.1371/journal.pone.0184773] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 08/30/2017] [Indexed: 12/22/2022] Open
Abstract
Inflammation has been shown to play an important role in the mechanisms involved in the pathogenesis of hypertension. Connexins (Cxs)-based gap junction channels (GJCs) or hemichannels (HCs) are involved in the maintenance of homeostasis in the immune system. However, the role of Cx43-based channels in T-lymphocytes in mediating the immune response in essential hypertension is not fully understand. The present study was designed to investigate the role of Cxs-based channels in T lymphocytes in the regulation of hypertension-mediated inflammation. The surface expressions of T lymphocyte subtypes, Cx40/Cx43, and inflammatory cytokines (IFN-γ (interferon-gamma) and TNF-ɑ (tumor necrosis factor alpha)) in T cells, as well as gap junction communication of peripheral blood lymphocytes from essential hypertensive patients (EHs) and normotensive healthy subjects (NTs) were detected by flow cytometry. Expression levels and phosphorylation of Cx43 protein in peripheral blood lymphocytes of EHs and NTs were analyzed by Western blot. The proliferation rate of peripheral blood mononuclear cells (PBMCs) after treatment with a Cxs inhibitor was examined by a CCK-8 assay. The levels of inflammatory cytokines were detected using ELISA. Within the CD3+ T cell subsets, we found a significant trend toward an increase in the percentage of CD4+ T cells and CD4+/CD8+ ratio as well as in serum levels of IFN-γ and TNF-ɑ in the peripheral blood of EHs compared with those in NTs. Moreover, the peripheral blood lymphocytes of EH patients exhibited enhanced GJCs formation, increased Cx43 protein level and Cx43 phosphorylation at Ser368, and a significant increase in Cx40/Cx43 surface expressions levels in CD4+ or CD8+ T lymphocytes. Cx43-based channel inhibition by a mimetic peptide greatly reduced the exchange of dye between lymphocytes, proliferation of stimulated lymphocytes and the pro-inflammatory cytokine levels of EHs and NTs. Our data suggest that Cx40/Cx43-based channels in lymphocytes may be involved in the regulation of T lymphocyte proliferation and the production of pro-inflammatory cytokines, which contribute to the hypertensive inflammatory response.
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Affiliation(s)
- Xin Ni
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Ai Wang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Liang Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Li-Ya Shan
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Hai-Chao Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Li Li
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Jun-Qiang Si
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Jian Luo
- The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China
| | - Xin-Zhi Li
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Department of Pathophysiology, Medical College of Shihezi University, Shihezi, Xinjiang, China
| | - Ke-Tao Ma
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, China.,Key Laboratory of Xingjiang Endemic and Ethnic Diseases, Medical College of Shihezi University, Shihezi, Xinjiang, China
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17
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Gleisner MA, Navarrete M, Hofmann F, Salazar-Onfray F, Tittarelli A. Mind the Gaps in Tumor Immunity: Impact of Connexin-Mediated Intercellular Connections. Front Immunol 2017; 8:1067. [PMID: 28919895 PMCID: PMC5585150 DOI: 10.3389/fimmu.2017.01067] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 08/16/2017] [Indexed: 12/22/2022] Open
Abstract
Gap junctions (GJs)-mediated intercellular communications (GJICs) are connexin (Cx)-formed plasma membrane channels that allow for the passage of small molecules between adjacent cells, and are involved in several physiopathological processes, including immune responses against cancer. In general, tumor cells are poorly coupled through GJs, mainly due to low Cx expression or reduced channel activity, suggesting that Cxs may have tumor suppressor roles. However, more recent data indicate that Cxs and/or GJICs may also in some cases promote tumor progression. This dual role of Cx channels in tumor outcome may be due, at least partially, to the fact that GJs not only interconnect cells from the same type, such as cancer cells, but also promote the intercellular communication of tumor cells with different types of cells from their microenvironment, and such diverse intercellular interactions have distinctive impact on tumor development. For example, whereas GJ-mediated interactions among tumor cells and microglia have been implicated in promotion of tumor growth, tumor cells delivery to dendritic cells of antigenic peptides through GJs have been associated with enhanced immune-mediated tumor elimination. In this review, we provide an updated overview on the role of GJICs in tumor immunity, focusing on the pro-tumor and antitumor effect of GJs occurring among tumor and immune cells. Accumulated data suggest that GJICs may act as tumor suppressors or enhancers depending on whether tumor cells interact predominantly with antitumor immune cells or with stromal cells. The complex modulation of immune-tumor cell GJICs should be taken into consideration in order to potentiate current cancer immunotherapies.
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Affiliation(s)
- María Alejandra Gleisner
- Disciplinary Program of Immunology, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, Santiago, Chile.,Faculty of Medicine, Millennium Institute on Immunology and Immunotherapy, Universidad de Chile, Santiago, Chile
| | - Mariela Navarrete
- Disciplinary Program of Immunology, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, Santiago, Chile.,Faculty of Medicine, Millennium Institute on Immunology and Immunotherapy, Universidad de Chile, Santiago, Chile
| | - Francisca Hofmann
- Disciplinary Program of Immunology, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, Santiago, Chile.,Faculty of Medicine, Millennium Institute on Immunology and Immunotherapy, Universidad de Chile, Santiago, Chile
| | - Flavio Salazar-Onfray
- Disciplinary Program of Immunology, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, Santiago, Chile.,Faculty of Medicine, Millennium Institute on Immunology and Immunotherapy, Universidad de Chile, Santiago, Chile
| | - Andrés Tittarelli
- Disciplinary Program of Immunology, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, Santiago, Chile.,Faculty of Medicine, Millennium Institute on Immunology and Immunotherapy, Universidad de Chile, Santiago, Chile
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18
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Hasegawa DK, Erickson SL, Hersh BM, Turnbull MW. Virus Innexins induce alterations in insect cell and tissue function. JOURNAL OF INSECT PHYSIOLOGY 2017; 98:173-181. [PMID: 28077262 DOI: 10.1016/j.jinsphys.2017.01.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 10/10/2016] [Accepted: 01/06/2017] [Indexed: 06/06/2023]
Abstract
Polydnaviruses are dsDNA viruses that induce immune and developmental alterations in their caterpillar hosts. Characterization of polydnavirus gene families and family members is necessary to understand mechanisms of pathology and evolution of these viruses, and may aid to elucidate the role of host homologues if present. For example, the polydnavirus vinnexin gene family encodes homologues of insect gap junction genes (innexins) that are expressed in host immune cells (hemocytes). While the roles of Innexin proteins and gap junctions in insect immunity are largely unclear, we previously demonstrated that Vinnexins form functional gap junctions and alter the junctional characteristics of a host Innexin when co-expressed in paired Xenopus oocytes. Here, we test the effect of ectopic vinnexin expression on host cell physiology using both a lepidopteran cell culture model and a dipteran whole organism model. Vinnexin expression in the cell culture system resulted in gene-specific alterations in cell morphology and a slight, but non-statistically significant, reduction in gap junction activity as measured by dye transfer, while ectopic expression of a lepidopteran innexin2 gene led to morphological alterations and increase in gap junction activity. Global ectopic expression in the model dipteran, Drosophila melanogaster, of one vinnexin (vinnexinG) or D. melanogaster innexin2 (Dm-inx2) resulted in embryonic lethality, while expression of the other vinnexin genes had no effect. Furthermore, ectopic expression of vinnexinG, but not other vinnexin genes or Dm-inx2, in D. melanogaster larval gut resulted in developmental arrest in the pupal stage. These data indicate the vinnexins likely have gene-specific roles in host manipulation. They also support the use of Drosophila in further analysis of the role of Vinnexins and other polydnavirus genes in modifying host physiological processes. Finally, our findings suggest the vinnexin genes may be useful to perturb and characterize the physiological functions of insect Innexins.
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Affiliation(s)
- Daniel K Hasegawa
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA.
| | | | - Bradley M Hersh
- Department of Biology, Allegheny College, Meadville, PA 16335, USA.
| | - Matthew W Turnbull
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA; Department of Plant and Environmental Sciences, Clemson University, Clemson, SC 29634, USA.
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19
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Willebrords J, Crespo Yanguas S, Maes M, Decrock E, Wang N, Leybaert L, Kwak BR, Green CR, Cogliati B, Vinken M. Connexins and their channels in inflammation. Crit Rev Biochem Mol Biol 2016; 51:413-439. [PMID: 27387655 PMCID: PMC5584657 DOI: 10.1080/10409238.2016.1204980] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inflammation may be caused by a variety of factors and is a hallmark of a plethora of acute and chronic diseases. The purpose of inflammation is to eliminate the initial cell injury trigger, to clear out dead cells from damaged tissue and to initiate tissue regeneration. Despite the wealth of knowledge regarding the involvement of cellular communication in inflammation, studies on the role of connexin-based channels in this process have only begun to emerge in the last few years. In this paper, a state-of-the-art overview of the effects of inflammation on connexin signaling is provided. Vice versa, the involvement of connexins and their channels in inflammation will be discussed by relying on studies that use a variety of experimental tools, such as genetically modified animals, small interfering RNA and connexin-based channel blockers. A better understanding of the importance of connexin signaling in inflammation may open up towards clinical perspectives.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Michaël Maes
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Elke Decrock
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Nan Wang
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Brenda R. Kwak
- Department of Pathology and Immunology and Division of Cardiology,
University of Geneva, Rue Michel-Servet 1, CH-1211 Geneva, Switzerland; Brenda R.
Kwak: Tel: +41 22 379 57 37
| | - Colin R. Green
- Department of Ophthalmology and New Zealand National Eye Centre,
University of Auckland, New Zealand; Colin R. Green: Tel: +64 9 923 61 35
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal
Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87,
05508-270 São Paulo, Brazil; Bruno Cogliati: Tel: +55 11 30 91 12 00
| | - Mathieu Vinken
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
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Glass AM, Snyder EG, Taffet SM. Connexins and pannexins in the immune system and lymphatic organs. Cell Mol Life Sci 2015; 72:2899-910. [PMID: 26100515 PMCID: PMC11113820 DOI: 10.1007/s00018-015-1966-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 06/11/2015] [Indexed: 12/11/2022]
Abstract
Connexin43 and pannexin1 are found in immune cells. While gap junctional communication has been demonstrated between immune cells, hemichannels have been implicated in many cellular functions. Among the functions involved as being connexin dependent and pannexin dependent are cell migration, phagocytosis, antigen presentation, T-cell reactivity and B-cell responses. Surprisingly, many of these connexin-related and pannexin-related functions are not recapitulated in in vivo models. This is leading to a reevaluation of the role of these proteins in immune function.
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Affiliation(s)
- Aaron M. Glass
- Department of Microbiology and Immunology, SUNY Upstate Medical University, 750 E Adams Street, Syracuse, NY 13210 USA
| | - Elizabeth G. Snyder
- Department of Microbiology and Immunology, SUNY Upstate Medical University, 750 E Adams Street, Syracuse, NY 13210 USA
| | - Steven M. Taffet
- Department of Microbiology and Immunology, SUNY Upstate Medical University, 750 E Adams Street, Syracuse, NY 13210 USA
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González-Nieto D, Chang KH, Fasciani I, Nayak R, Fernandez-García L, Barrio LC, Cancelas JA. Connexins: Intercellular Signal Transmitters in Lymphohematopoietic Tissues. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 318:27-62. [PMID: 26315883 DOI: 10.1016/bs.ircmb.2015.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Life-long hematopoietic demands are met by a pool of hematopoietic stem cells (HSC) with self-renewal and multipotential differentiation ability. Humoral and paracrine signals from the bone marrow (BM) hematopoietic microenvironment control HSC activity. Cell-to-cell communication through connexin (Cx) containing gap junctions (GJs) allows pluricellular coordination and synchronization through transfer of small molecules with messenger activity. Hematopoietic and surrounding nonhematopoietic cells communicate each other through GJs, which regulate fetal and postnatal HSC content and function in hematopoietic tissues. Traffic of HSC between peripheral blood and BM is also dependent on Cx proteins. Cx mutations are associated with human disease and hematopoietic dysfunction and Cx signaling may represent a target for therapeutic intervention. In this review, we illustrate and highlight the importance of Cxs in the regulation of hematopoietic homeostasis under normal and pathological conditions.
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Affiliation(s)
- Daniel González-Nieto
- Unit of Cellular and Animal Models, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid, Spain; Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
| | - Kyung-Hee Chang
- Division of Experimental Hematology and Cancer Biology, Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA; Hoxworth Blood Center, University of Cincinnati, Cincinnati, OH, USA
| | - Ilaria Fasciani
- Unit of Experimental Neurology, Hospital Ramon y Cajal, Madrid, Spain
| | - Ramesh Nayak
- Division of Experimental Hematology and Cancer Biology, Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Laura Fernandez-García
- Unit of Cellular and Animal Models, Center for Biomedical Technology, Universidad Politécnica de Madrid, Madrid, Spain
| | - Luis C Barrio
- Unit of Experimental Neurology, Hospital Ramon y Cajal, Madrid, Spain
| | - José A Cancelas
- Division of Experimental Hematology and Cancer Biology, Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA; Hoxworth Blood Center, University of Cincinnati, Cincinnati, OH, USA
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22
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Connexin 43 communication channels in follicular dendritic cell development and in follicular lymphomas. J Immunol Res 2015; 2015:528098. [PMID: 25815348 PMCID: PMC4359865 DOI: 10.1155/2015/528098] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 02/09/2015] [Accepted: 02/11/2015] [Indexed: 02/05/2023] Open
Abstract
Follicular dendritic cells (FDC) show homo- and heterocellular metabolic coupling through connexin 43 (Cx43) gap junctions and support B cell selection and maturation in germinal centers. In follicular lymphomas B cells escape apoptosis while FDC develop abnormally. Here we tested Cx43 channels in reactive FDC development and follicular lymphomas. In culture, the treatment of FDC-B cell clusters (resembling to “ex vivo” germinal centers) with Gap27 peptide, mimicking the 2nd extracellular loop of Cx43 protein, significantly impaired FDC-B cell cluster formation and cell survival. In untreated cultures of intact clusters, cell proliferation showed a moderate reduction. In tissues, Cx43 protein levels run parallel with the density of FDC both in reactive germinal centers and in malformed follicles of follicular lymphomas and showed strong upregulation in newly generated and/or degrading bi-/multinuclear FDC of rudimentary processes. However, the inverse correlation between Cx43 expression and B cell proliferation seen in reactive germinal centers was not detected in follicular lymphomas. Furthermore, Cx43 levels were not associated with either lymphoma grade or bone marrow involvement. Our results suggest that Cx43 channels are critical in FDC and “ex vivo” germinal center development and in the persistence of FDC in follicular lymphomas but do not affect tumor progression.
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23
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Sáez PJ, Shoji KF, Aguirre A, Sáez JC. Regulation of hemichannels and gap junction channels by cytokines in antigen-presenting cells. Mediators Inflamm 2014; 2014:742734. [PMID: 25301274 PMCID: PMC4180397 DOI: 10.1155/2014/742734] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 06/19/2014] [Indexed: 12/13/2022] Open
Abstract
Autocrine and paracrine signals coordinate responses of several cell types of the immune system that provide efficient protection against different challenges. Antigen-presenting cells (APCs) coordinate activation of this system via homocellular and heterocellular interactions. Cytokines constitute chemical intercellular signals among immune cells and might promote pro- or anti-inflammatory effects. During the last two decades, two membrane pathways for intercellular communication have been demonstrated in cells of the immune system. They are called hemichannels (HCs) and gap junction channels (GJCs) and provide new insights into the mechanisms of the orchestrated response of immune cells. GJCs and HCs are permeable to ions and small molecules, including signaling molecules. The direct intercellular transfer between contacting cells can be mediated by GJCs, whereas the release to or uptake from the extracellular milieu can be mediated by HCs. GJCs and HCs can be constituted by two protein families: connexins (Cxs) or pannexins (Panxs), which are present in almost all APCs, being Cx43 and Panx1 the most ubiquitous members of each protein family. In this review, we focus on the effects of different cytokines on the intercellular communication mediated by HCs and GJCs in APCs and their impact on purinergic signaling.
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Affiliation(s)
- Pablo J. Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
| | - Kenji F. Shoji
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
| | - Adam Aguirre
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
| | - Juan C. Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
- Instituto Milenio, Centro Interdisciplinario de Neurociencias de Valparaíso, Pasaje Harrington 287, Playa Ancha, 2360103 Valparaíso, Chile
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Connexin 43 expression on peripheral blood eosinophils: role of gap junctions in transendothelial migration. BIOMED RESEARCH INTERNATIONAL 2014; 2014:803257. [PMID: 25110696 PMCID: PMC4109672 DOI: 10.1155/2014/803257] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 06/11/2014] [Accepted: 06/12/2014] [Indexed: 01/10/2023]
Abstract
Eosinophils circulate in the blood and are recruited in tissues during allergic inflammation. Gap junctions mediate direct communication between adjacent cells and may represent a new way of communication between immune cells distinct from communication through cytokines and chemokines. We characterized the expression of connexin (Cx)43 by eosinophils isolated from atopic individuals using RT-PCR, Western blotting, and confocal microscopy and studied the biological functions of gap junctions on eosinophils. The formation of functional gap junctions was evaluated measuring dye transfer using flow cytometry. The role of gap junctions on eosinophil transendothelial migration was studied using the inhibitor 18-a-glycyrrhetinic acid. Peripheral blood eosinophils express Cx43 mRNA and protein. Cx43 is localized not only in the cytoplasm but also on the plasma membrane. The membrane impermeable dye BCECF transferred from eosinophils to epithelial or endothelial cells following coculture in a dose and time dependent fashion. The gap junction inhibitors 18-a-glycyrrhetinic acid and octanol did not have a significant effect on dye transfer but reduced dye exit from eosinophils. The gap junction inhibitor 18-a-glycyrrhetinic acid inhibited eosinophil transendothelial migration in a dose dependent manner. Thus, eosinophils from atopic individuals express Cx43 constitutively and Cx43 may play an important role in eosinophil transendothelial migration and function in sites of inflammation.
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25
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Schalper KA, Carvajal-Hausdorf D, Oyarzo MP. Possible role of hemichannels in cancer. Front Physiol 2014; 5:237. [PMID: 25018732 PMCID: PMC4073485 DOI: 10.3389/fphys.2014.00237] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 06/09/2014] [Indexed: 12/12/2022] Open
Abstract
In humans, connexins (Cxs) and pannexins (Panxs) are the building blocks of hemichannels. These proteins are frequently altered in neoplastic cells and have traditionally been considered as tumor suppressors. Alteration of Cxs and Panxs in cancer cells can be due to genetic, epigenetic and post-transcriptional/post-translational events. Activated hemichannels mediate the diffusional membrane transport of ions and small signaling molecules. In the last decade hemichannels have been shown to participate in diverse cell processes including the modulation of cell proliferation and survival. However, their possible role in tumor growth and expansion remains largely unexplored. Herein, we hypothesize about the possible role of hemichannels in carcinogenesis and tumor progression. To support this theory, we summarize the evidence regarding the involvement of hemichannels in cell proliferation and migration, as well as their possible role in the anti-tumor immune responses. In addition, we discuss the evidence linking hemichannels with cancer in diverse models and comment on the current technical limitations for their study.
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Affiliation(s)
- Kurt A Schalper
- Servicio Anatomía Patológica, Clínica Alemana de Santiago, Facultad de Medicina Clinica Alemana Universidad del Desarrollo Santiago, Chile ; Department of Pathology, Yale School of Medicine New Haven, CT, USA
| | | | - Mauricio P Oyarzo
- Servicio Anatomía Patológica, Clínica Alemana de Santiago, Facultad de Medicina Clinica Alemana Universidad del Desarrollo Santiago, Chile
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26
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Tittarelli A, Mendoza-Naranjo A, Farías M, Guerrero I, Ihara F, Wennerberg E, Riquelme S, Gleisner A, Kalergis A, Lundqvist A, López MN, Chambers BJ, Salazar-Onfray F. Gap junction intercellular communications regulate NK cell activation and modulate NK cytotoxic capacity. THE JOURNAL OF IMMUNOLOGY 2013; 192:1313-9. [PMID: 24376266 DOI: 10.4049/jimmunol.1301297] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Gap junctions (GJs) mediate intercellular communication between adjacent cells. Previously, we showed that connexin 43 (Cx43), the main GJ protein in the immune system, mediates Ag transfer between human dendritic cells (DCs) and is recruited to the immunological synapse during T cell priming. This crosstalk contributed to T cell activation, intracellular Ca(2+) responses, and cytokine release. However, the role of GJs in NK cell activation by DCs and NK cell-mediated cytotoxicity against tumor cells remains unknown. In this study, we found polarization of Cx43 at the NK/DC and NK/tumor cell-contact sites, accompanied by the formation of functional GJs between NK/DCs and NK/tumor cells, respectively. Cx43-GJ-mediated intercellular communication (GJIC) between human NK and DCs was bidirectional. Blockage of Cx43-GJIC inhibited NK cell activation, though it affected neither the phenotype nor the function of DCs. Cx43 knockdown or inhibition using mimetic peptides greatly reduced CD69 and CD25 expression and IFN-γ release by DC-stimulated NK cells. Moreover, blocking Cx43 strongly inhibited the NK cell-mediated tumor cell lysis associated with inhibition of granzyme B activity and Ca(2+) influx. Our data identify a novel and active role for Cx43-GJIC in human NK cell activation and antitumor effector functions that may be important for the design of new immune therapeutic strategies.
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Affiliation(s)
- Andrés Tittarelli
- Faculty of Medicine, Institute of Biomedical Sciences, University of Chile, 8380453 Santiago, Chile
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Nielsen MS, Axelsen LN, Sorgen PL, Verma V, Delmar M, Holstein-Rathlou NH. Gap junctions. Compr Physiol 2013; 2:1981-2035. [PMID: 23723031 DOI: 10.1002/cphy.c110051] [Citation(s) in RCA: 298] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease.
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Affiliation(s)
- Morten Schak Nielsen
- Department of Biomedical Sciences and The Danish National Research Foundation Centre for Cardiac Arrhythmia, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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28
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Gutiérrez-Vázquez C, Villarroya-Beltri C, Mittelbrunn M, Sánchez-Madrid F. Transfer of extracellular vesicles during immune cell-cell interactions. Immunol Rev 2013; 251:125-42. [PMID: 23278745 DOI: 10.1111/imr.12013] [Citation(s) in RCA: 242] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The transfer of molecules between cells during cognate immune cell interactions has been reported, and recently a novel mechanism of transfer of proteins and genetic material such as small RNA between T cells and antigen-presenting cells (APCs) has been described, involving exchange of extracellular vesicles (EVs) during the formation of the immunological synapse (IS). EVs, a term that encompasses exosomes and microvesicles, has been implicated in cell-cell communication during immune responses associated with tumors, pathogens, allergies, and autoimmune diseases. This review focuses on EV transfer as a mechanism for the exchange of molecules during immune cell-cell interactions.
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29
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Regulation of gap junctions in melanoma and their impact on Melan-A/MART-1-specific CD8⁺ T lymphocyte emergence. J Mol Med (Berl) 2013; 91:1207-20. [PMID: 23744108 DOI: 10.1007/s00109-013-1058-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 05/15/2013] [Accepted: 05/16/2013] [Indexed: 10/26/2022]
Abstract
UNLABELLED Gap junctions (GJs) enable intercellular communication between adjacent cells through channels of connexins. Using a three-dimensional construct, we previously showed that endothelial and tumor cells formed GJs, allowing melanoma-specific T lymphocytes to recognize and kill melanoma-derived endothelial cells. We demonstrate here on histological sections of melanoma biopsies that GJ formation occurs in vivo between tumor and endothelial cells and between T lymphocytes and target cells. We also show an in vitro increase of GJ formation in melanoma and endothelial cells following dacarbazin and interferon gamma (IFN-γ) treatment or hypoxic stress induction. Our data indicate that although connexin 43 (Cx43), the main GJ protein of the immune system, was localized at the immunological synapse between T lymphocyte and autologous melanoma cells, its over-expression or inhibition of GJs does not interfere with cytotoxic T lymphocyte (CTL) clone lytic function. In contrast, we showed that inhibition of GJs by oleamide during stimulation of resting PBMCs with Melan-A natural and analog peptides resulted in a decrease in antigen (Ag) specific CD8(+) T lymphocyte induction. These Ag-specific CD8(+) cells displayed paradoxically stronger reactivity as revealed by CD107a degranulation and IFN-γ secretion. These findings indicate that Cx43 does not affect lytic function of differentiated CTL, but reveal a major role for GJs in the regulation of antigen CD8(+)-naïve T lymphocyte activation. KEY MESSAGE GJ formation occurs in vivo between T lymphocytes and tumor cells Cx43 localized at the immunological synapse between T and autologous melanoma cells Inhibition of GJs resulted in a decrease in Ag-specific CD8(+) T lymphocyte induction A role for GJs in the regulation of antigen CD8(+)-naïve T lymphocyte activation.
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30
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Ehrlich HP. A Snapshot of Direct Cell-Cell Communications in Wound Healing and Scarring. Adv Wound Care (New Rochelle) 2013; 2:113-121. [PMID: 24527335 DOI: 10.1089/wound.2012.0414] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Indexed: 01/09/2023] Open
Abstract
SIGNIFICANCE The repair of wounds usually terminates with a scar. The healing from a severe tissue loss can create a new clinical problem, excessive scarring. Approaches to prevent excessive scarring will optimize the repair process. Controlling gap-junction communications between cells and/or the transport of the proteins that form gap junctions offers new approaches for controlling this problem. RECENT ADVANCES Gap-junctional intercellular communication (GJIC) requires hemichannels, connexon structures, embedded in the plasma membrane of coupled cells. The connexon is composed of six proteins from the connexin (Cx) family. The docking of connexons between the neighboring cells forms a gated channel, where small molecules can pass directly between the cytoplasm of cells. In wound repair, GJIC between fibroblasts in granulation tissue advances wound repair. Also, the GJIC between mast cells and fibroblasts during the remodeling phase of repair may explain how mast cells promote excessive scarring. In addition, Cx can affect transforming growth factor beta (TGF-β) intracellular signaling through its shared binding site on microtubules within fibroblasts. CRITICAL ISSUES Can excessive scarring be controlled through limiting the local amassing of mast cells or preventing their interactions with wound fibroblasts through GJIC? FUTURE DIRECTIONS The prevention of the accumulation of mast cells in granulation tissue or interfering with their communications via GJIC with fibroblasts offers new approaches for preventing excess scarring. The association of Cx with microtubules altering TGF-β signaling presents a new target for improving the quality of repair as well as the deposition of unnecessary fibrosis.
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Affiliation(s)
- H. Paul Ehrlich
- Division of Plastic Surgery, Department of Surgery, Penn State College of Medicine, Hershey, Pennsylvania
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31
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Li K, Chi Y, Gao K, Yan Q, Matsue H, Takeda M, Kitamura M, Yao J. Connexin43 hemichannel-mediated regulation of connexin43. PLoS One 2013; 8:e58057. [PMID: 23460926 PMCID: PMC3584027 DOI: 10.1371/journal.pone.0058057] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 01/31/2013] [Indexed: 01/24/2023] Open
Abstract
Background Many signaling molecules and pathways that regulate gap junctions (GJs) protein expression and function are, in fact, also controlled by GJs. We, therefore, speculated an existence of the GJ channel-mediated self-regulation of GJs. Using a cell culture model in which nonjunctional connexin43 (Cx43) hemichannels were activated by cadmium (Cd2+), we tested this hypothesis. Principal Findings Incubation of Cx43-transfected LLC-PK1 cells with Cd2+ led to an increased expression of Cx43. This effect of Cd2+ was tightly associated with JNK activation. Inhibition of JNK abolished the elevation of Cx43. Further analysis revealed that the changes of JNK and Cx43 were controlled by GSH. Supplement of a membrane-permeable GSH analogue GSH ethyl ester or GSH precursor N-acetyl-cystein abrogated the effects of Cd2+ on JNK activation and Cx43 expression. Indeed, Cd2+ induced extracellular release of GSH. Blockade of Cx43 hemichannels with heptanol or Cx43 mimetic peptide Gap26 to prevent the efflux of GSH significantly attenuated the Cx43-elevating effects of Cd2+. Conclusions Collectively, our results thus indicate that Cd2+-induced upregulation of Cx43 is through activation of nonjunctional Cx43 hemichannels. Our findings thus support the existence of a hemichannel-mediated self-regulation of Cx43 and provide novel insights into the molecular mechanisms of Cx43 expression and function.
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Affiliation(s)
- Kai Li
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
- Department of Urology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
- Department of Surgical Oncology and General Surgery, First Hospital of China Medical University, Shenyang, China
- * E-mail: (JY); (KL)
| | - Yuan Chi
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Kun Gao
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Qiaojing Yan
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Hiroyuki Matsue
- Department of Dermatology, Chiba University School of Medicine, Chiba, Japan
| | - Masayuki Takeda
- Department of Urology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Masanori Kitamura
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Jian Yao
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan
- * E-mail: (JY); (KL)
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32
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Deva NC, Zhang J, Green CR, Danesh-Meyer HV. Connexin43 modulation inhibits scarring in a rabbit eye glaucoma trabeculectomy model. Inflammation 2013; 35:1276-86. [PMID: 22427153 DOI: 10.1007/s10753-012-9439-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We investigated whether one subconjunctival injection of connexin43 antisense oligodeoxynucleotides (Cx43 AsODN) modulates postoperative scarring in a rabbit model of glaucoma trabeculectomy surgery. In a randomised, controlled, masked-observer study, 39 rabbits underwent trabeculectomy surgery with insertion of a 22-gauge cannula in the right eyes and were randomly divided into three treatment groups. Each rabbit received an injection of Cx43 AsODN in Pluronic gel, balanced salt solution or Pluronic gel alone into the formed bled. The animals were euthanized at 8 and 24 h and at 5 and 21 days. Histology and immunohistochemistry results demonstrated that Cx43 AsODN decreased Cx43 upregulation at 8 and 24 h which led to less myofibroblast upregulation at days 5 and 21 and reduced scarring at day 21 compared to controls. We conclude that postoperative use of Cx43 AsODN inhibited subconjunctival scarring and fibrosis. Cx43 AsODN injection may be a safe and effective anti-scarring agent in glaucoma trabeculectomy surgery.
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Affiliation(s)
- Narmadai C Deva
- Department of Ophthalmology, University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland, 1142, New Zealand
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33
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Evans WH, Bultynck G, Leybaert L. Manipulating connexin communication channels: use of peptidomimetics and the translational outputs. J Membr Biol 2012; 245:437-49. [PMID: 22886208 PMCID: PMC3456916 DOI: 10.1007/s00232-012-9488-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 07/07/2012] [Indexed: 12/22/2022]
Abstract
Gap junctions are key components underpinning multicellularity. They provide cell to cell channel pathways that enable direct intercellular communication and cellular coordination in tissues and organs. The channels are constructed of a family of connexin (Cx) membrane proteins. They oligomerize inside the cell, generating hemichannels (connexons) composed of six subunits arranged around a central channel. After transfer to the plasma membrane, arrays of Cx hemichannels (CxHcs) interact and couple with partners in neighboring attached cells to generate gap junctions. Cx channels have been studied using a range of technical approaches. Short peptides corresponding to sequences in the extra- and intracellular regions of Cxs were used first to generate epitope-specific antibodies that helped studies on the organization and functions of gap junctions. Subsequently, the peptides themselves, especially Gap26 and -27, mimetic peptides derived from each of the two extracellular loops of connexin43 (Cx43), a widely distributed Cx, have been extensively applied to block Cx channels and probe the biology of cell communication. The development of a further series of short peptides mimicking sequences in the intracellular loop, especially the extremity of the intracellular carboxyl tail of Cx43, followed. The primary inhibitory action of the peptidomimetics occurs at CxHcs located at unapposed regions of the cell's plasma membrane, followed by inhibition of cell coupling occurring across gap junctions. CxHcs respond to a range of environmental conditions by increasing their open probability. Peptidomimetics provide a way to block the actions of CxHcs with some selectivity. Furthermore, they are increasingly applied to address the pathological consequences of a range of environmental stresses that are thought to influence Cx channel operation. Cx peptidomimetics show promise as candidates in developing new therapeutic approaches for containing and reversing damage inflicted on CxHcs, especially in hypoxia and ischemia in the heart and in brain functions.
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Affiliation(s)
- W Howard Evans
- Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, Wales CF14 4XN, UK.
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Mendoza-Naranjo A, Bouma G, Pereda C, Ramírez M, Webb KF, Tittarelli A, López MN, Kalergis AM, Thrasher AJ, Becker DL, Salazar-Onfray F. Functional gap junctions accumulate at the immunological synapse and contribute to T cell activation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 187:3121-32. [PMID: 21844382 PMCID: PMC3173876 DOI: 10.4049/jimmunol.1100378] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Gap junction (GJ) mediates intercellular communication through linked hemichannels from each of two adjacent cells. Using human and mouse models, we show that connexin 43 (Cx43), the main GJ protein in the immune system, was recruited to the immunological synapse during T cell priming as both GJs and stand-alone hemichannels. Cx43 accumulation at the synapse was Ag specific and time dependent, and required an intact actin cytoskeleton. Fluorescence recovery after photobleaching and Cx43-specific inhibitors were used to prove that intercellular communication between T cells and dendritic cells is bidirectional and specifically mediated by Cx43. Moreover, this intercellular cross talk contributed to T cell activation as silencing of Cx43 with an antisense or inhibition of GJ docking impaired intracellular Ca(2+) responses and cytokine release by T cells. These findings identify Cx43 as an important functional component of the immunological synapse and reveal a crucial role for GJs and hemichannels as coordinators of the dendritic cell-T cell signaling machinery that regulates T cell activation.
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Affiliation(s)
- Ariadna Mendoza-Naranjo
- Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, 8380453 Santiago, Chile.
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Oviedo-Orta E, Perreau M, Evans WH, Potolicchio I. Control of the proliferation of activated CD4+T cells by connexins. J Leukoc Biol 2010; 88:79-86. [DOI: 10.1189/jlb.0909613] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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36
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Ring S, Karakhanova S, Johnson T, Enk AH, Mahnke K. Gap junctions between regulatory T cells and dendritic cells prevent sensitization of CD8(+) T cells. J Allergy Clin Immunol 2010; 125:237-46.e1-7. [PMID: 20109751 DOI: 10.1016/j.jaci.2009.10.025] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 09/28/2009] [Accepted: 10/06/2009] [Indexed: 11/15/2022]
Abstract
BACKGROUND Regulatory T (Treg) cells suppress the sensitization phase of experimental contact hypersensitivity (CHS) reactions when injected before hapten application. OBJECTIVE Our aim was to analyze the mechanisms by which Treg cells suppress the sensitization phase of CHS reactions. METHODS Treg cells were labeled with different fluorescent dyes and injected into naive mice directly before sensitization with the hapten 2,4,6-trinitro-1-chlorobenzene. Two days after sensitization, the lymphoid organs were analyzed for the presence of Treg cells and engagement of gap junctions with other cells. Dendritic cells (DCs) and effector CD8(+)T cells were isolated from the draining lymph nodes (LNs) of the differently treated groups, analyzed by using FACS for activation markers, and assessed for the T-cell stimulatory capacity of the DCs and the priming of effector T cells. RESULTS Only the LN-homing Treg cells suppressed the sensitization phase in CHS reactions by means of establishing gap junctions with DCs in the dLNs. This gap junctional intercellular communication led to downregulation of T-cell costimulatory molecules on the surface of the DCs, abrogating the priming, activation, and proliferation of hapten-specific CD8(+)T cells. Consequently, the ear-swelling response induced by challenge with the respective hapten was prevented. CONCLUSION Treg cells not only modulate ongoing CD4(+)T cell-mediated immune reactions at tissue sites but also abrogate the de novo induction of CD8(+)T cell-driven immune reactions by interfering with T-cell stimulatory activity of DCs through gap junctional intercellular communication.
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Affiliation(s)
- Sabine Ring
- Department of Dermatology, University Hospital Heidelberg, Vossstrasse 11, 69115 Heidelberg, Germany.
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37
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Zhang Y, Wang H, Kovacs A, Kanter EM, Yamada KA. Reduced expression of Cx43 attenuates ventricular remodeling after myocardial infarction via impaired TGF-beta signaling. Am J Physiol Heart Circ Physiol 2009; 298:H477-87. [PMID: 19966054 DOI: 10.1152/ajpheart.00806.2009] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In addition to mediating cell-to-cell electrical coupling, gap junctions are important in tissue repair, wound healing, and scar formation. The expression and distribution of connexin43 (Cx43), the major gap junction protein expressed in the heart, are altered substantially after myocardial infarction (MI); however, the effects of Cx43 remodeling on wound healing and the attendant ventricular dysfunction are incompletely understood. Cx43-deficient and wild-type mice were subjected to proximal ligation of the anterior descending coronary artery and followed for 6 days or 4 wk to test the hypothesis that reduced expression of Cx43 influences wound healing, fibrosis, and ventricular remodeling after MI. We quantified the progression of infarct healing by measuring neutrophil expression, collagen content, and myofibroblast expression. We found significantly reduced transformation of fibroblasts to myofibroblasts at 6 days and significantly reduced collagen deposition both in the infarct at 6 days and at 4 wk in the noninfarcted region of Cx43-deficient mice. As expected, transforming growth factor (TGF)-beta, a profibrotic cytokine, was dramatically upregulated in MI hearts, but its phosphorylated comediator (pSmad) was significantly downregulated in the nuclei of Cx43-deficient hearts post-MI, suggesting that downstream signaling of TGF-beta is diminished substantially in Cx43-deficient hearts. This diminution in profibrotic TGF-beta signaling resulted in the attenuation of adverse structural remodeling as assessed by echocardiography. These findings suggest that efforts to enhance the expression of Cx43 to maintain intercellular coupling or reduce susceptibility to arrhythmias should be met with caution until the role of Cx43 in infarct healing is fully understood.
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Affiliation(s)
- Yan Zhang
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
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38
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A model system to study Connexin 43 in the immune system. Mol Immunol 2009; 46:2938-46. [PMID: 19608277 DOI: 10.1016/j.molimm.2009.06.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 06/11/2009] [Accepted: 06/18/2009] [Indexed: 11/21/2022]
Abstract
Connexin 43 (Cx43) is the predominant gap junction protein expressed in immune cells. Previous manuscripts have stated that gap junctions may play a role in antigen cross-presentation, dendritic cell maturation, T cell development, and regulatory T cell function. Many of these previous studies were performed in vitro. In vivo studies were not directly possible in adult mice because Cx43-/- mice die shortly after birth due to a cardiac malformation. To overcome these drawbacks, we have developed a mouse model that deletes Cx43 in the immune system while maintaining normal cardiac function. In our model, irradiated CD45.1+ wild-type mice were reconstituted with Cx43WT, Cx43+/-, or Cx43-/- hematopoietic fetal liver cells that were derived from CD45.2+ mice. The presence of CD45.2 allowed us to identify and track the donor cells following reconstitution. We determined that Cx43+/- and Cx43-/- hematopoietic cells were able to reconstitute irradiated mice as well as Cx43WT cells. Reconstitution was nearly 100% in the thymus and over 90% in the spleen. There appeared to be no difference in thymocyte development or in the ability of lymphocytes to transmigrate to peripheral lymphoid organs. However in response to inflammation, Cx43+/- radiation chimeras had increased peritoneal infiltration compared to Cx43WT and Cx43-/- groups. IgG responses were normal in all groups but the Cx43-/- reconstituted mice had an elevated IgM response. Our data suggests that Cx43 may not be involved in the normal development of the immune system but may regulate certain effector functions in vivo.
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Handel A, Yates A, Pilyugin SS, Antia R. Sharing the burden: antigen transport and firebreaks in immune responses. J R Soc Interface 2008; 6:447-54. [PMID: 18708323 DOI: 10.1098/rsif.2008.0258] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Communication between cells is crucial for immune responses. An important means of communication during viral infections is the presentation of viral antigen on the surface of an infected cell. Recently, it has been shown that antigen can be shared between infected and uninfected cells through gap junctions, connexin-based channels, that allow the transport of small molecules. The uninfected cell receiving antigen can present it on its surface. Cells presenting viral antigen are detected and killed by cytotoxic T lymphocytes. The killing of uninfected cells can lead to increased immunopathology. However, the immune response might also profit from killing those uninfected bystander cells. One benefit might be the removal of future 'virus factories'. Another benefit might be through the creation of 'firebreaks', areas void of target cells, which increase the diffusion time of free virions, making their clearance more likely. Here, we use theoretical models and simulations to explore how the mechanism of gap junction-mediated antigen transport (GMAT) affects the dynamics of the virus and immune response. We show that under the assumption of a well-mixed system, GMAT leads to increased immunopathology, which always outweighs the benefit of reduced virus production due to the removal of future virus factories. By contrast, a spatially explicit model leads to quite different results. Here we find that the firebreak mechanism reduces both viral load and immunopathology. Our study thus shows the potential benefits of GMAT and illustrates how spatial effects may be crucial for the quantitative understanding of infection dynamics and immune responses.
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Affiliation(s)
- Andreas Handel
- Department of Biology, Emory University, Atlanta, GA 30322, USA
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40
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Evans WH, Leybaert L. Mimetic peptides as blockers of connexin channel-facilitated intercellular communication. ACTA ACUST UNITED AC 2008; 14:265-73. [PMID: 18392994 DOI: 10.1080/15419060801891034] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
There is a dearth of chemical inhibitors of connexin-mediated intercellular communication. The advent of short "designer" connexin mimetic peptides has provided new tools to inhibit connexin channels quickly and reversibly. This perspective describes the development of mimetic peptides, especially Gap 26 and 27 that are the most popular and correspond to specific sequences in the extracellular loops of connexins 37, 40 and 43. Initially they were used to inhibit gap-junctional coupling in a wide range of mammalian cells and tissues. Currently, they are also being examined as therapeutic agents that accelerate wound healing and in the early treatment of spinal cord injury. The mimetic peptides bind to connexin hemichannels, influencing channel properties as shown by lowering of electrical conductivity and potently blocking the entry of small reporter dyes and the release of ATP by cells. A mechanism is proposed to help explain the dual action of connexin mimetic peptides on connexin hemichannels and gap-junctional coupling.
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Affiliation(s)
- W Howard Evans
- Department of Medical Biochemistry and Immunology, Wales Heart Research Institute Cardiff University Medical School, Heath Park, Cardiff, UK.
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41
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Abstract
Gap junctions facilitate direct cytoplasmic communication between neighboring cells, facilitating the transfer of small molecular weight molecules involved in cell signaling and metabolism. Gap junction channels are formed by the joining of two hemichannels from adjacent cells, each composed of six oligomeric protein subunits called connexins. Of paramount importance to CNS homeostasis are astrocyte networks formed by gap junctions, which play a critical role in maintaining the homeostatic regulation of extracellular pH, K+, and glutamate levels. Inflammation is a hallmark of several diseases afflicting the CNS. Within the past several years, the number of publications reporting effects of cytokines and pathogenic stimuli on glial gap junction communication has increased dramatically. The purpose of this review is to discuss recent observations characterizing the consequences of inflammatory stimuli on homocellular gap junction coupling in astrocytes and microglia as well as changes in connexin expression during various CNS inflammatory conditions.
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Affiliation(s)
- Tammy Kielian
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
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42
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Rhett JM, Ghatnekar GS, Palatinus JA, O'Quinn M, Yost MJ, Gourdie RG. Novel therapies for scar reduction and regenerative healing of skin wounds. Trends Biotechnol 2008; 26:173-80. [PMID: 18295916 DOI: 10.1016/j.tibtech.2007.12.007] [Citation(s) in RCA: 165] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 12/12/2007] [Accepted: 12/12/2007] [Indexed: 11/30/2022]
Abstract
Fibrotic scars deposited during skin wound healing can cause disfiguration and loss of dermal function. Scar differentiation involves inputs from multiple cell types in a predictable and overlapping sequence of cellular events that includes inflammation, migration/proliferation and extracellular matrix deposition. Research into the molecular mechanisms underpinning these processes in embryonic and adult wounds has contributed to the development of a growing number of novel therapeutic approaches for improving scar appearance. This review discusses some of these emerging strategies for shifting the balance of healing from scarring to regeneration in the context of non-pathological wounds. Particular focus is given to potential therapies based on transforming growth factor (TGF)-beta signaling and recent unexpected findings involving targeting of gap junctional connexins. Lessons learned in promoting scarless healing of cutaneous injuries might provide a basis for regenerative healing in other scenarios, such as spinal cord rupture or myocardial infarction.
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Affiliation(s)
- J Matthew Rhett
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, SC 29425, USA
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43
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Handel A, Yates A, Pilyugin SS, Antia R. Gap junction-mediated antigen transport in immune responses. Trends Immunol 2007; 28:463-6. [DOI: 10.1016/j.it.2007.08.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Revised: 08/14/2007] [Accepted: 08/14/2007] [Indexed: 12/26/2022]
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44
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Mendoza-Naranjo A, Saéz PJ, Johansson CC, Ramírez M, Mandakovic D, Pereda C, López MN, Kiessling R, Sáez JC, Salazar-Onfray F. Functional gap junctions facilitate melanoma antigen transfer and cross-presentation between human dendritic cells. THE JOURNAL OF IMMUNOLOGY 2007; 178:6949-57. [PMID: 17513744 DOI: 10.4049/jimmunol.178.11.6949] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Previously, we found that human dendritic cells (hDCs) pulsed with a melanoma cell lysate (MCL) and stimulated with TNF-alpha (MCL/TNF) acquire a mature phenotype in vitro and are able to trigger tumor-specific immune responses when they are used in melanoma immunotherapy in patients. In this study, we describe that MCL/TNF induces gap junction (GJ)-mediated intercellular communications and promotes melanoma Ag transfer between ex vivo produced hDCs from melanoma patients. hDCs also exhibit increased expression of the GJ-related protein connexin 43, which contributes to GJ plaque formation after MCL/TNF stimulation. The addition of GJ inhibitors suppresses intercellular tumor Ag transfer between hDCs, thus reducing melanoma-specific T cell activation. In summary, we demonstrate that MCL/TNF-stimulated hDCs can establish functional GJ channels that participate in melanoma Ag transfer, facilitating Ag cross-presentation and an effective dendritic cell-mediated melanoma-specific T cell response. These results suggest that GJs formed between hDCs used in cancer vaccination protocols could be essentials for the establishment of a more efficient antitumor response.
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Affiliation(s)
- Ariadna Mendoza-Naranjo
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
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45
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Bermudez-Fajardo A, Ylihärsilä M, Evans WH, Newby AC, Oviedo-Orta E. CD4+ T lymphocyte subsets express connexin 43 and establish gap junction channel communication with macrophages in vitro. J Leukoc Biol 2007; 82:608-12. [PMID: 17596336 PMCID: PMC2847614 DOI: 10.1189/jlb.0307134] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Gap junction channels constructed of connexins (Cxs) are expressed by peripheral and secondary lymphoid organ-derived lymphocytes. These channels in the plasma membrane play key roles in a range of lymphocyte functions exemplified by the synthesis and secretion of Igs and cytokines and during transmigration across the endothelium. Most recently, their involvement in antigen cross-presentation has also been established. We report here for the first time the expression of mRNA and protein encoding Cx43 in mouse-derived CD4+ Th0, Th1, and Th2 lymphocyte subpopulations and demonstrate the establishment gap junction channel formation with primary macrophages in vitro. We show that this mode of direct communication is particularly favored in Th1-macrophage interactions and that LPS inhibits lymphocyte-macrophage cross-talk independently of the subset of lymphocyte involved. Our work suggests that gap junction-mediated communication can be modulated in the absence of specific antigenic stimulation. Therefore, a further mechanism featuring gap junction-mediated communication may be implicated in immune regulation.
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Affiliation(s)
| | - Minna Ylihärsilä
- School of Biomedical and Molecular Sciences, University of Surrey, Guildford, United Kingdom
| | - W. Howard Evans
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Wales, United Kingdom
| | - Andrew C. Newby
- Bristol Heart Institute, Bristol Royal Infirmary, Bristol, United Kingdom
| | - Ernesto Oviedo-Orta
- School of Biomedical and Molecular Sciences, University of Surrey, Guildford, United Kingdom
- Correspondence: School of Biomedical and Molecular Sciences, University of Surrey, Guildford GU2 7XH, UK.
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46
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Mori R, Power KT, Wang CM, Martin P, Becker DL. Acute downregulation of connexin43 at wound sites leads to a reduced inflammatory response, enhanced keratinocyte proliferation and wound fibroblast migration. J Cell Sci 2007; 119:5193-203. [PMID: 17158921 DOI: 10.1242/jcs.03320] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Experimental downregulation of connexin43 (Cx43) expression at skin wound sites appears to markedly improve the rate and quality of healing, but the underlying mechanisms are currently unknown. Here, we have compared physiological and cell biological aspects of the repair process with and without Cx43 antisense oligodeoxynucleotide treatment. Treated wounds exhibited accelerated skin healing with significantly increased keratinocyte and fibroblast proliferation and migration. In vitro knockdown of Cx43 in a fibroblast wound-healing model also resulted in significantly faster healing, associated with increased mRNA for TGF-beta1, and collagen alpha1 and general collagen content at the wound site. Treated wounds showed enhanced formation of granulation tissue and maturation with more rapid angiogenesis, myofibroblast differentiation and wound contraction appeared to be advanced by 2-3 days. Recruitment of both neutrophils and macrophages was markedly reduced within treated wounds, concomitant with reduced leukocyte infiltration. In turn, mRNA levels of CC chemokine ligand 2 and TNF-alpha were reduced in the treated wound. These data suggest that, by reducing Cx43 protein with Cx43-specific antisense oligodeoxynucleotides at wound sites early in the skin healing process repair is enhanced, at least in part, by accelerating cell migration and proliferation, and by attenuating inflammation and the additional damage it can cause.
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Affiliation(s)
- Ryoichi Mori
- Department of Physiology, School of Medical Sciences, University of Bristol, University Walk, Bristol BS8 1TD, UK
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47
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Neijssen J, Pang B, Neefjes J. Gap junction-mediated intercellular communication in the immune system. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2007; 94:207-18. [PMID: 17467043 DOI: 10.1016/j.pbiomolbio.2007.03.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Immune cells are usually considered non-attached blood cells, which would exclude the formation of gap junctions. This is a misconception since many immune cells express connexin 43 (Cx43) and other connexins and are often residing in tissue. The role of gap junctions is largely ignored by immunologists as is the immune system in the field of gap junction research. Here, the current knowledge of the distribution of connexins and the function of gap junctions in the immune system is discussed. Gap junctions appear to play many roles in antibody productions and specific immune responses and may be important in sensing danger in tissue by the immune system. Gap junctions not only transfer electrical and metabolical but also immunological information in the form of peptides for a process called cross-presentation. This is essential for proper immune responses to viruses and possibly tumours. Until now only 40 research papers on gap junctions in the immune system appeared and this will almost certainly expand with the increased mutual interest between the fields of immunology and gap junction research.
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Affiliation(s)
- Joost Neijssen
- Division of Tumor Biology, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam, The Netherlands
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48
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Abstract
This article continues the ongoing debate around models of the immune system. Earlier contributors have paid much attention to the various processes that lead to adaptive immune system aggression or tolerance. They have often based their discussions around facts that have been established by experimental investigation. However, both the observation and interpretation of these facts have been influenced by the function--or system goal--that is believed to have generated them. The perception of this function (of all or part of the immune system) is influenced by long established theories in immunology (e.g. horror autotoxicus, clonal deletion in utero, pathogen elimination, clonal selection, auto-immunity and so on) which, for many, have become enshrined as facts. One function that has had less consideration and has not been extensively investigated is the maintenance of tissue homeostasis. When the immune system is viewed from this perspective, the facts invite alternative interpretations. Whilst this perspective may not necessarily be the only valid one, let alone a correct one, viewing things this way--at least briefly--might help to expose hidden assumptions. It also emphasizes that the immune system is a system and, as such, it can by analysed through the principles of general systems theory.
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49
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Evans WH, De Vuyst E, Leybaert L. The gap junction cellular internet: connexin hemichannels enter the signalling limelight. Biochem J 2006; 397:1-14. [PMID: 16761954 PMCID: PMC1479757 DOI: 10.1042/bj20060175] [Citation(s) in RCA: 331] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Revised: 03/22/2006] [Accepted: 03/23/2006] [Indexed: 02/07/2023]
Abstract
Cxs (connexins), the protein subunits forming gap junction intercellular communication channels, are transported to the plasma membrane after oligomerizing into hexameric assemblies called connexin hemichannels (CxHcs) or connexons, which dock head-to-head with partner hexameric channels positioned on neighbouring cells. The double membrane channel or gap junction generated directly couples the cytoplasms of interacting cells and underpins the integration and co-ordination of cellular metabolism, signalling and functions, such as secretion or contraction in cell assemblies. In contrast, CxHcs prior to forming gap junctions provide a pathway for the release from cells of ATP, glutamate, NAD+ and prostaglandin E2, which act as paracrine messengers. ATP activates purinergic receptors on neighbouring cells and forms the basis of intercellular Ca2+ signal propagation, complementing that occuring more directly via gap junctions. CxHcs open in response to various types of external changes, including mechanical, shear, ionic and ischaemic stress. In addition, CxHcs are influenced by intracellular signals, such as membrane potential, phosphorylation and redox status, which translate external stresses to CxHc responses. Also, recent studies demonstrate that cytoplasmic Ca2+ changes in the physiological range act to trigger CxHc opening, indicating their involvement under normal non-pathological conditions. CxHcs not only respond to cytoplasmic Ca2+, but also determine cytoplasmic Ca2+, as they are large conductance channels, suggesting a prominent role in cellular Ca2+ homoeostasis and signalling. The functions of gap-junction channels and CxHcs have been difficult to separate, but synthetic peptides that mimic short sequences in the Cx subunit are emerging as promising tools to determine the role of CxHcs in physiology and pathology.
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Affiliation(s)
- W Howard Evans
- Department of Medical Biochemistry and Immunology and the Wales Heart Research Institute, Cardiff University Medical School, Cardiff CF14 4XN, Wales, UK.
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50
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Matsue H, Yao J, Matsue K, Nagasaka A, Sugiyama H, Aoki R, Kitamura M, Shimada S. Gap Junction-Mediated Intercellular Communication between Dendritic Cells (DCs) Is Required for Effective Activation of DCs. THE JOURNAL OF IMMUNOLOGY 2005; 176:181-90. [PMID: 16365409 DOI: 10.4049/jimmunol.176.1.181] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Gap junctions, formed by members of the connexin (Cx) family, are intercellular channels allowing direct exchange of signaling molecules. Gap junction-mediated intercellular communication (GJIC) is a widespread mechanism for homeostasis in organs. GJIC in the immune system is not yet fully understood. Although dendritic cells (DC) reportedly form cell-to-cell contact between DCs in nonlymphoid and lymphoid organs, GJIC between DCs remains unknown. In this study we examined whether DCs form GJIC. XS52 and bone marrow-derived DCs (BMDCs) were tested for GJIC by counting intercellular transfer of Lucifer Yellow microinjected into a cell. Either DC became effectively dye-coupled when activated with LPS plus IFN-gamma or TNF-alpha plus IFN-gamma. LPS- plus IFN-gamma-induced dye-coupling was mediated by DC-derived TNF-alpha. In addition, CpG plus IFN-gamma induced dye-coupling in BMDCs, which was also mediated by DC-derived TNF-alpha. LPS- plus IFN-gamma-induced activation of DCs (assessed by CD40 expression) was observed when there was cell-to-cell contact and was significantly blocked by heptanol, a gap junction blocker. These results indicate that cell-to-cell contact and GJIC are required for effective DC activation. In addition, heptanol significantly inhibited the LPS- plus IFN-gamma-induced up-regulation of the other costimulatory (i.e., CD80 and CD86) and MHC class II molecules expressed by BMDCs, and it significantly reduced their allostimulatory capacity. Among Cx members, Cx43 was up-regulated in dye-coupled BMDCs, and Cx mimetic peptide, a blocker of Cx-mediated GJIC, significantly inhibited the dye-coupling and activation, suggesting the involvement of Cx43. Thus, our study provides the first evidence for GJIC between DCs, which is required for effective DC activation.
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Affiliation(s)
- Hiroyuki Matsue
- Department of Dermatology, University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering Tamaho, Yamanashi, Japan.
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