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Sana M, Rashid M, Rashid I, Akbar H, Gomez-Marin JE, Dimier-Poisson I. Immune response against toxoplasmosis-some recent updates RH: Toxoplasma gondii immune response. Int J Immunopathol Pharmacol 2022; 36:3946320221078436. [PMID: 35227108 PMCID: PMC8891885 DOI: 10.1177/03946320221078436] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
AIMS Cytokines, soluble mediators of immunity, are key factors of the innate and adaptive immune system. They are secreted from and interact with various types of immune cells to manipulate host body's immune cell physiology for a counter-attack on the foreign body. A study was designed to explore the mechanism of Toxoplasma gondii (T. gondii) resistance from host immune response. METHODS AND RESULTS The published data on aspect of host (murine and human) immune response against T. gondii was taken from Google scholar and PubMed. Most relevant literature was included in this study. The basic mechanism of immune response starts from the interactions of antigens with host immune cells to trigger the production of cytokines (pro-inflammatory and anti-inflammatory) which then act by forming a cytokinome (network of cytokine). Their secretory equilibrium is essential for endowing resistance to the host against infectious diseases, particularly toxoplasmosis. A narrow balance lying between Th1, Th2, and Th17 cytokines (as demonstrated until now) is essential for the development of resistance against T. gondii as well as for the survival of host. Excessive production of pro-inflammatory cytokines leads to tissue damage resulting in the production of anti-inflammatory cytokines which enhances the proliferation of Toxoplasma. Stress and other infectious diseases (human immunodeficiency virus (HIV)) that weaken the host immunity particularly the cellular component, make the host susceptible to toxoplasmosis especially in pregnant women. CONCLUSION The current review findings state that in vitro harvesting of IL12 from DCs, Np and MΦ upon exposure with T. gondii might be a source for therapeutic use in toxoplasmosis. Current review also suggests that therapeutic interventions leading to up-regulation/supplementation of SOCS-3, IL12, and IFNγ to the infected host could be a solution to sterile immunity against T. gondii infection. This would be of interest particularly in patients passing through immunosuppression owing to any reason like the ones receiving anti-cancer therapy, the ones undergoing immunosuppressive therapy for graft/transplantation, the ones suffering from immunodeficiency virus (HIV) or having AIDS. Another imortant suggestion is to launch the efforts for a vaccine based on GRA6Nt or other similar antigens of T. gondii as a probable tool to destroy tissue cysts.
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Affiliation(s)
- Madiha Sana
- Department of Parasitology, 66920University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Rashid
- Department of Parasitology, Faculty of Veterinary and Animal Sciences, 66920The Islamia University of Bahawalpur, Pakistan
| | - Imran Rashid
- Department of Parasitology, 66920University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Haroon Akbar
- Department of Parasitology, 66920University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Jorge E Gomez-Marin
- Grupo Gepamol, Centro de Investigaciones Biomedicas, Universidad del Quindio, Armenia, CO, South America
| | - Isabelle Dimier-Poisson
- Université de Tours, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Unité mixte de recherche 1282 (UMR1282), Infectiologie et santé publique (ISP), Tours, France
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Ihara F, Tanaka S, Fereig RM, Nishimura M, Nishikawa Y. Involvement of Toll-like receptor 2 in the cerebral immune response and behavioral changes caused by latent Toxoplasma infection in mice. PLoS One 2019; 14:e0220560. [PMID: 31404078 PMCID: PMC6690529 DOI: 10.1371/journal.pone.0220560] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 07/18/2019] [Indexed: 02/07/2023] Open
Abstract
Subacute and chronic infections with the intracellular protozoan parasite Toxoplasma gondii are associated with an increased risk of psychiatric diseases like schizophrenia. However, little is known about the mechanisms involved in T. gondii-induced neuronal disorders. Recently, we reported that Toll-like receptor 2 (TLR2) was required to initiate the innate immune response in cultured mouse brain cells. However, how TLR2 contributes to latent infection with T. gondii remains unclear. Therefore, we examined the role of TLR2 in brain pathology and behavior using wild-type (TLR2+/+) and TLR2-deficient (TLR2-/-) mice. The behavioral analyses showed that TLR2 deficiency increased the anxiety state of the uninfected and infected animals alike, and TLR2 deficiency showed no relationship with the infection. In the contextual and cued fear-conditioning tests, T. gondii infection decreased the mouse freezing reaction while TLR2 deficiency increased it, but there was no interaction between the two factors. Our histopathological analysis showed that the TLR2+/+ and TLR2-/- mice had similar brain lesions at 30 days post infection (dpi) with T. gondii. Higher numbers of parasites were detected in the brains of the TLR2-/- mice than in those from the TLR2+/+ mice at 30 dpi, but not at 7 and 14 dpi. No significant differences were observed in the proinflammatory gene expression levels in the TLR2+/+ and TLR2-/- mice. Therefore, it appears that TLR2 signaling in the brain might contribute to the control of parasite growth, but not to brain pathology or the impaired fear memory response induced by infection with T. gondii.
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Affiliation(s)
- Fumiaki Ihara
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan
| | - Sachi Tanaka
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan
| | - Ragab M. Fereig
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan
- Department of Animal Medicine, Faculty of Veterinary Medicine, South Valley University, Qena City, Qena, Egypt
| | - Maki Nishimura
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan
| | - Yoshifumi Nishikawa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan
- * E-mail:
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Interleukin-17A-Deficient Mice Are Highly Susceptible to Toxoplasma gondii Infection Due to Excessively Induced T. gondii HSP70 and Interferon Gamma Production. Infect Immun 2017; 85:IAI.00399-17. [PMID: 28893913 DOI: 10.1128/iai.00399-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 09/01/2017] [Indexed: 11/20/2022] Open
Abstract
Interleukin17A (IL-17A) is known to be involved in the host defense against pathogens and the pathogenesis of autoimmune diseases. Previously, we showed that excessive amounts of interferon gamma (IFN-γ) play an important role in the pathogenesis of the lethal effects of Toxoplasma gondii by inducing anaphylactic responses. In the study described in this report, we examined the effects of IL-17A deficiency on murine host defense against oral T. gondii infection. IL-17A-deficient C57BL/6 (B6) mice exhibited higher rates of mortality than wild-type (WT) mice during the acute phase of T. gondii infection. CD4+ T cells in the mesenteric lymph nodes (mLNs) and ileum of T. gondii-infected IL-17A-deficient mice produced higher levels of IFN-γ than did those of WT mice. In addition, the level of T. gondii HSP70 (T.gHSP70) expression was also significantly increased in the ileum, mLNs, liver, and spleen of infected IL-17A-deficient mice compared with that in WT mice. These elevated levels of expression of T.gHSP70 and IFN-γ in infected IL-17A-deficient mice were presumably linked to the IL-17A defect since they decreased to WT levels after treatment with recombinant IL-17A. Furthermore, IL-17A-deficient mice were highly susceptible to the anaphylactic effect of T.gHSP70, and the survival of IL-17A-deficient mice during the acute phase was improved by treatment with an anti-T.gHSP70 monoclonal antibody. These results suggest that IL-17A plays an important role in host survival against T. gondii infection by protecting the host from an anaphylactic reaction via the downregulation of T.gHSP70 and IFN-γ production.
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Ghosh D, Stumhofer JS. Do you see what I see: Recognition of protozoan parasites by Toll-like receptors. ACTA ACUST UNITED AC 2014; 9:129-140. [PMID: 25383072 DOI: 10.2174/1573395509666131203225929] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Toll-like receptors (TLRs) are important for recognizing a variety of pathogens, including protozoan parasites, and initiating innate immune responses against them. TLRs are localized on the cell surface as well as in the endosome, and are implicated in innate sensing of these parasites. In this review, we will discuss recent findings on the identification of parasite-derived pathogen associated molecular patterns and the TLRs that bind them. The role of these TLRs in initiating the immune response against protozoan parasitic infections in vivo will be presented in the context of murine models of infection utilizing TLR-deficient mice. Additionally, we will explore evidence that TLRs and genetic variants of TLRs may impact the outcome of these parasitic infections in humans.
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Affiliation(s)
- Debopam Ghosh
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Jason S Stumhofer
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR 72205
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von Bernuth H, Picard C, Puel A, Casanova JL. Experimental and natural infections in MyD88- and IRAK-4-deficient mice and humans. Eur J Immunol 2013; 42:3126-35. [PMID: 23255009 PMCID: PMC3752658 DOI: 10.1002/eji.201242683] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 08/11/2012] [Accepted: 10/25/2012] [Indexed: 01/15/2023]
Abstract
Most Toll-like-receptors (TLRs) and interleukin-1 receptors (IL-1Rs) signal via myeloid differentiation primary response 88 (MyD88) and interleukin-1 receptor-associated kinase 4 (IRAK-4). The combined roles of these two receptor families in the course of experimental infections have been assessed in MyD88- and IRAK-4-deficient mice for almost fifteen years. These animals have been shown to be susceptible to 46 pathogens: 27 bacteria, eight viruses, seven parasites, and four fungi. Humans with inborn MyD88 or IRAK-4 deficiency were first identified in 2003. They suffer from naturally occurring life-threatening infections caused by a small number of bacterial species, although the incidence and severity of these infections decrease with age. Mouse TLR- and IL-1R-dependent immunity mediated by MyD88 and IRAK-4 seems to be vital to combat a wide array of experimentally administered pathogens at most ages. By contrast, human TLR- and IL-1R-dependent immunity mediated by MyD88 and IRAK-4 seems to be effective in the natural setting against only a few bacteria and is most important in infancy and early childhood. The roles of TLRs and IL-1Rs in protective immunity deduced from studies in mutant mice subjected to experimental infections should therefore be reconsidered in the light of findings for natural infections in humans carrying mutations as discussed in this review.
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Affiliation(s)
- Horst von Bernuth
- Pediatric Pneumology and Immunology, Charité Hospital - Humboldt University, Berlin, Germany.
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6
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Impaired innate immunity in mice deficient in interleukin-1 receptor-associated kinase 4 leads to defective type 1 T cell responses, B cell expansion, and enhanced susceptibility to infection with Toxoplasma gondii. Infect Immun 2012; 80:4298-308. [PMID: 23027530 DOI: 10.1128/iai.00328-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Interleukin-1 receptor (IL1R)-associated kinase 4 (IRAK4) is a member of the IRAK family and has an important role in inducing the production of inflammatory mediators. This kinase is downstream of MyD88, an adaptor protein essential for Toll-like receptor (TLR) function. We investigated the role of this kinase in IRAK4-deficient mice orally infected with the cystogenic ME49 strain of Toxoplasma gondii. IRAK4(-/-) mice displayed higher morbidity, tissue parasitism, and accelerated mortality than the control mice. The lymphoid follicles and germinal centers from infected IRAK4(-/-) mice were significantly smaller. We consistently found that IRAK4(-/-) mice showed a defect in splenic B cell activation and expansion as well as diminished production of gamma interferon (IFN-γ) by T lymphocytes. The myeloid compartment was also affected. Both the frequency and ability of dendritic cells (DCs) and monocytes/macrophages to produce IL-12 were significantly decreased, and resistance to infection with Toxoplasma was rescued by treating IRAK4(-/-) mice with recombinant IL-12 (rIL-12). Additionally, we report the association of IRAK4 haplotype-tagging single nucleotide polymorphisms (tag-SNPs) with congenital toxoplasmosis in infected individuals (rs1461567 and rs4251513, P < 0.023 and P < 0.045, respectively). Thus, signaling via IRAK4 is essential for the activation of innate immune cells, development of parasite-specific acquired immunity, and host resistance to infection with T. gondii.
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Critical coordination of innate immune defense against Toxoplasma gondii by dendritic cells responding via their Toll-like receptors. Proc Natl Acad Sci U S A 2010; 108:278-83. [PMID: 21173242 DOI: 10.1073/pnas.1011549108] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Toll-like receptors (TLRs) play an important role in host defense against a variety of microbial pathogens. We addressed the mechanism by which TLRs contribute to host defense against the lethal parasite Toxoplasma gondii by using mice with targeted inactivation of the TLR adaptor protein myeloid differentiation primary response gene 88 (MyD88) in different innate cell types. Lack of MyD88 in dendritic cells (DCs), but not in macrophages or neutrophils, resulted in high susceptibility to the T. gondii infection. In the mice deficient in MyD88 in DCs, the early IL-12 response by DCs was ablated, the IFN-γ response by natural killer cells was delayed, and the recruited inflammatory monocytes were incapable of killing the T. gondii parasites. The T-cell response, although attenuated in these mice, was sufficient to eradicate the parasite during the chronic stage, provided that defects in DC activation were compensated by IL-12 treatment early after infection. These results demonstrate a central role of DCs in orchestrating the innate immune response to an intracellular pathogen and establish that defects in pathogen recognition by DCs can predetermine sensitivity to infection.
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Silvestre R, Silva AM, Cordeiro-da-Silva A, Ouaissi A. The contribution of Toll-like receptor 2 to the innate recognition of a Leishmania infantum silent information regulator 2 protein. Immunology 2010; 128:484-99. [PMID: 19930041 DOI: 10.1111/j.1365-2567.2009.03132.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
We have characterized a Leishmania protein belonging to the silent information regulator 2 (SIR2) family [SIR2 related protein 1 (SIR2RP1)] that might play an immunoregulatory role during infection through its capacity to trigger B-cell effector functions. We report here that SIR2RP1 leads to the proliferation of activated B cells, causing increased expression of major histocompatibility complex (MHC) II and the costimulatory molecules CD40 and CD86, which are critical ligands for T-cell cross-talk during the development of adaptive immune responses. In contrast, B cells isolated from Toll-like receptor 2 (TLR2) knockout mice were unable to respond to the SIR2RP1 stimulus. Similarly, SIR2RP1 induced the maturation of dendritic cells (DCs) in a TLR2-dependent manner with the secretion of pro-inflammatory cytokines [interleukin (IL)-12 and tumour necrosis factor (TNF)-alpha] and enhanced the costimulatory properties of DCs. Nevertheless, immunization assays demonstrated that TLR2-deficient mice were able to mount a specific humoral response to SIR2RP1. Interestingly, further investigations showed that macrophages were activated by SIR2RP1 even in the absence of TLR2. Therefore, a different type of interplay between SIR2RP1 and the major antigen-presenting cells in vivo could explain the immune response observed in TLR2-deficient mice. Together, these results demonstrate that TLR2 signalling contributes to SIR2RP1 recognition by innate immune host cells.
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Affiliation(s)
- Ricardo Silvestre
- Parasite Disease Group, Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
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9
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Flores M, Saavedra R, Bautista R, Viedma R, Tenorio EP, Leng L, Sánchez Y, Juárez I, Satoskar AA, Shenoy AS, Terrazas LI, Bucala R, Barbi J, Satoskar AR, Rodriguez-Sosa M. Macrophage migration inhibitory factor (MIF) is critical for the host resistance against Toxoplasma gondii. FASEB J 2008; 22:3661-71. [PMID: 18606868 DOI: 10.1096/fj.08-111666] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Macrophage migration inhibitory factor (MIF) exerts either a protective or a deleterious role in the immune response to different pathogens. We analyzed herein the role of MIF in the host control of toxoplasmosis using MIF(-/-) mice backcrossed to either the BALB/c or the C57BL/6 genetic backgrounds. Both, wild-type (WT) BALB/c and MIF(-/-) BALB/c mice were susceptible to infection with highly virulent RH as well as moderately virulent ME49 strains of T. gondii. MIF(-/-) mice, however, showed greater liver damage and more brain cysts, produced less proinflammatory cytokines, and succumbed significantly faster than WT mice. Bone marrow-derived dendritic cells (BMDCs) from MIF(-/-) mice produced less interleukin-1beta, interleukin-12, and tumor necrosis factor-alpha than WT BMDCs after stimulation with soluble Toxoplasma antigen (STAg). Similar observations were made in CD11c(+) low-density cells isolated from the spleens of MIF(-/-) mice challenged with STAg. MIF(-/-) C57BL/6 mice succumbed to ME49 infection faster than their WT counterparts. C57BL/6 mice that succumbed to infection with the ME49 strain produced less MIF than resistant BALB/c mice similarly infected. Interestingly, an analysis of brains from patients with cerebral toxoplasmosis showed low levels of MIF expression. Together, these findings demonstrate that MIF plays a critical role in mediating host resistance against T. gondii.
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Affiliation(s)
- Marcos Flores
- Unidad de Biomedicina, FES-Iztacala, UNAM. Av. de los Barrios #1, Los Reyes Iztacala, 54090 Tlalnepantla, Mexico City, Mexico
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Role of TLRs/MyD88 in host resistance and pathogenesis during protozoan infection: lessons from malaria. Semin Immunopathol 2007; 30:41-51. [PMID: 18071705 DOI: 10.1007/s00281-007-0103-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Accepted: 11/07/2007] [Indexed: 01/23/2023]
Abstract
Toll-like receptors (TLRs) are important to initiate the innate immune response to a wide variety of pathogens. The protective role of TLRs during infection with protozoan parasites has been established. In this regard, malaria represents an exception where activation of TLRs seems to be deleterious to the host. In this article, we review the recent findings indicating the contrasting role of Myeloid Differentiation Primary-Response gene 88 (MyD88) and TLRs during malaria and infection with other protozoa. These findings suggest that MyD88 may represent an Achilles' heel during Plasmodium infection.
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Aosai F, Rodriguez Pena MS, Mun HS, Fang H, Mitsunaga T, Norose K, Kang HK, Bae YS, Yano A. Toxoplasma gondii-derived heat shock protein 70 stimulates maturation of murine bone marrow-derived dendritic cells via Toll-like receptor 4. Cell Stress Chaperones 2006; 11:13-22. [PMID: 16572725 PMCID: PMC1400610 DOI: 10.1379/csc-138r.1] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Toxoplasma gondii-derived heat shock protein 70 (T.g.HSP70) induced maturation of bone marrow-derived dendritic cells (DCs) of wild-type (WT) C57BL/6 mice as evidenced by an increase in surface expression of MHC class I and II molecules and costimulatory molecules such as CD40, CD80, and CD86. Functionally, decreased phagocytic ability and increased alloreactive T cell stimulatory ability were observed in T.g.HSP70-stimulated DCs. These phenotypic and functional changes of T.g.HSP70-stimulated DCs were demonstrated in Toll-like receptor (TLR) 2- and myeloid differentiation factor 88 (MyD88)-deficient but not TLR4-deficient C57BL/6 mice. DCs from WT and TLR2-deficient but not TLR4-deficient mice produced IL-12 after T.g.HSP70 stimulation. T.g.HSP70-stimulated DCs from WT, TLR2-deficient, and MyD88-deficient, but not TLR4-deficient mice expressed IFN-beta mRNA. Thus, T.g.HSP70 stimulates murine DC maturation via TLR4 through the MyD88-independent signal transduction cascade.
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Affiliation(s)
- Fumie Aosai
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuoku, Chiba 260-8670, Japan.
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12
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Rogers KA, Rogers AB, Leav BA, Sanchez A, Vannier E, Uematsu S, Akira S, Golenbock D, Ward HD. MyD88-dependent pathways mediate resistance to Cryptosporidium parvum infection in mice. Infect Immun 2006; 74:549-56. [PMID: 16369011 PMCID: PMC1346622 DOI: 10.1128/iai.74.1.549-556.2006] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Cryptosporidium spp. cause diarrheal disease worldwide. Innate immune responses mediating resistance to this parasite are not completely understood. To determine whether MyD88-dependent pathways play a role in resistance to Cryptosporidium parvum, we compared the course of infection in MyD88(-/-) mice to that in their wild-type (WT) littermate controls. Three- to 4-week-old mice were infected with C. parvum, and infection was monitored by quantifying fecal oocyst shedding. Twelve days postinfection, the histology of the intestines was examined to quantify intestinal parasite burden and to determine if there were any pathological changes. Fecal oocyst shedding and intestinal parasite burden were significantly greater in MyD88(-/-) mice than in littermate controls. Nonetheless, both WT and MyD88(-/-) mice cleared the infection within 3 weeks. These results indicate that MyD88-dependent pathways are involved in mediating initial resistance to C. parvum. Since gamma interferon (IFN-gamma) is known to mediate resistance to C. parvum, we also studied infection in MyD88(-/-) mice and WT controls in which this cytokine was temporarily neutralized. Fecal oocyst shedding, as well as intestinal parasite burden, intestinal inflammation, and mortality, was significantly greater in MyD88(-/-) mice in which IFN-gamma was neutralized than in IFN-gamma-neutralized WT mice or in MyD88(-/-) mice in which this cytokine was active. These results suggest that MyD88 and IFN-gamma had an additive effect in conferring protection from C. parvum infection. While this study confirms the importance of IFN-gamma in conferring resistance to infection with C. parvum, it suggests that MyD88-mediated pathways also play a role in innate immunity to this parasite.
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MESH Headings
- Adaptor Proteins, Signal Transducing/deficiency
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/physiology
- Animals
- Antigens, Differentiation/genetics
- Antigens, Differentiation/physiology
- Cryptosporidiosis/immunology
- Cryptosporidiosis/metabolism
- Cryptosporidiosis/mortality
- Cryptosporidium parvum/immunology
- Enterocolitis/immunology
- Enterocolitis/metabolism
- Enterocolitis/mortality
- Enterocolitis/parasitology
- Female
- Immunity, Innate/genetics
- Interferon-gamma/antagonists & inhibitors
- Interferon-gamma/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myeloid Differentiation Factor 88
- Receptors, Immunologic/deficiency
- Receptors, Immunologic/genetics
- Receptors, Immunologic/physiology
- Signal Transduction/genetics
- Signal Transduction/immunology
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Affiliation(s)
- K A Rogers
- Division of Geographic Medicine and Infectious Diseases, Tufts-New England Medical Center, 750 Washington Street, Boston, MA 02111, USA
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Schurr JR, Young E, Byrne P, Steele C, Shellito JE, Kolls JK. Central role of toll-like receptor 4 signaling and host defense in experimental pneumonia caused by Gram-negative bacteria. Infect Immun 2005; 73:532-45. [PMID: 15618193 PMCID: PMC538991 DOI: 10.1128/iai.73.1.532-545.2005] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toll-like receptor 4 (TLR4) has been identified as a receptor for lipopolysaccharide. However, the precise role of TLR4 in regulating gene expression in response to an infection caused by gram-negative bacteria has not been fully elucidated. The role of TLR4 signaling in coordinating gene expression was assessed by gene expression profiling in lung tissue in a mouse model of experimental pneumonia with a low-dose infection of Klebsiella pneumoniae. We analyzed four mouse strains: C57BL/6 mice, which are resistant to bacterial dissemination; 129/SvJ mice, which are susceptible; C3H/HeJ mice, which are susceptible and have defective TLR4 signaling; and their respective control strain, C3H/HeN (intermediate resistance). At 4 h after infection, C57BL/6 and C3H/HeN mice demonstrated the greatest number of genes, with 67 shared induced genes which were TLR4 dependent and highly associated with the resistance phenotype. These genes included cytokine and chemokine genes required for neutrophil activation or recruitment, growth factor receptors, MyD88 (a critical adaptor protein for TLR signaling), and adhesion molecules. TLR4 signaling accounted for over 74% of the gene expression in the C3H background. These data suggest that early TLR4 signaling controls the vast majority of gene expression in the lung in response to an infection caused by gram-negative bacteria and that this subsequent gene expression determines survival of the host.
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Affiliation(s)
- Jill R Schurr
- Children's Hospital of Pittsburgh, 3705 Fifth Ave., Suite 3765, Pittsburgh, PA 15213, USA
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14
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Fremond CM, Yeremeev V, Nicolle DM, Jacobs M, Quesniaux VF, Ryffel B. Fatal Mycobacterium tuberculosis infection despite adaptive immune response in the absence of MyD88. J Clin Invest 2005; 114:1790-9. [PMID: 15599404 PMCID: PMC535064 DOI: 10.1172/jci21027] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2004] [Accepted: 09/28/2004] [Indexed: 01/13/2023] Open
Abstract
Toll-like receptors (TLRs) such as TLR2 and TLR4 have been implicated in host response to mycobacterial infection. Here, mice deficient in the TLR adaptor molecule myeloid differentiation factor 88 (MyD88) were infected with Mycobacterium tuberculosis (MTB). While primary MyD88(-/-) macrophages and DCs are defective in TNF, IL-12, and NO production in response to mycobacterial stimulation, the upregulation of costimulatory molecules CD40 and CD86 is unaffected. Aerogenic infection of MyD88(-/-) mice with MTB is lethal within 4 weeks with 2 log(10) higher CFU in the lung; high pulmonary levels of cytokines and chemokines; and acute, necrotic pneumonia, despite a normal T cell response with IFN-gamma production to mycobacterial antigens upon ex vivo restimulation. Vaccination with Mycobacterium bovis bacillus Calmette-Guerin conferred a substantial protection in MyD88(-/-) mice from acute MTB infection. These data demonstrate that MyD88 signaling is dispensable to raise an acquired immune response to MTB. Nonetheless, this acquired immune response is not sufficient to compensate for the profound innate immune defect and the inability of MyD88(-/-) mice to control MTB infection.
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Affiliation(s)
- Cecile M Fremond
- CNRS, Molecular Immunology and Embryology, 3B rue de la Férollerie, 45071 Orléans, France
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Bannai H, Sakurai T, Inoue N, Sugimoto C, Igarashi I. Cloning and sxpression of mitochondrial heat shock protein 70 of Trypanosoma congolense and potential use as a diagnostic antigen. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2003; 10:926-33. [PMID: 12965928 PMCID: PMC193917 DOI: 10.1128/cdli.10.5.926-933.2003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The ability to use mitochondrial heat shock protein 70 (MTP) of Trypanosoma congolense as a diagnostic antigen was examined. One cDNA clone was obtained by immunoscreening of a T. congolense procyclic form (PCF) cDNA library with monoclonal antibody (MAb) 10F9. The cDNA clone contained an open reading frame of 1,977 bp encoding a polypeptide consisting of 659 amino acids. Southern blotting analysis indicated that there were at least three copies of the MTP gene in the haploid genome. Interference of the MTP RNA resulted in complete inhibition, which indicated that MTP is essential at the PCF stage. Northern and Western blotting analyses revealed that MTP is expressed both in the bloodstream form (BSF) and in PCF. The B-cell epitope recognized by MAb 10F9 was located within 206 amino acids from the C terminus. Depending on the conditions of protein extraction, MTP was cleaved into smaller polypeptides by endogenous proteases. However, the C-terminal epitope of MTP was preserved with a high degree of antigenicity, even after cleavage. Antibody detection by enzyme-linked immunosorbent assay with the truncated recombinant MTP revealed that anti-MTP antibodies exist in experimentally infected mouse sera. Thus, MTP may be useful as an antigen for the serodiagnosis of primary T. congolense infection.
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Affiliation(s)
- Hiroshi Bannai
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
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