Intricacies of TGF-β signaling in Treg and Th17 cell biology

Gender difference and BMDL exploration of developmental immunotoxicity induced by early-life low-dose exposure to 4-nonylphenol in Wistar rats

BACKGROUND

Nonylphenol (NP) is a widespread environmental endocrine disruptor with potential developmental immunotoxicity. The present study aimed to investigate the gender-specific developmental immunotoxic effects of early-life exposure to low doses of 4-nonylphenol (4-NP) on Wistar rats and the corresponding thresholds.

METHODS

Pregnant rats (F0 generation) were exposed to low doses of 4-NP from gestational day 6 (GD6) to postnatal day 90 (PND90), and F1 offspring continued to be exposed until the maturation of the immune system on PND42. We assessed immune organ development, immune responses, lymphocyte subset composition, cytokine secretion, and the Th17/Treg cell balance as endpoints for developmental immunotoxicity. Benchmark Dose analysis was conducted to explore the thresholds.

RESULTS

Early-life exposure to 4-NP led to significant gender-specific differences in the immune response. Female pups exhibited greater sensitivity to 4-NP, with reduced thymus and spleen weights, suppressed humoral immune function, decreased natural killer (NK) cell activity, and an imbalance in the Th17/Treg cell ratio. Male pups showed inhibition of NK cell activity but no significant changes in humoral immune function. Levels of phosphorylated STAT3, STAT5, and JAK3 proteins increased in the spleens of exposed pups of both gender. The lowest benchmark dose lower limit (BMDL) value of developmental immunotoxicity was lower in female rats (based on the thymus weight) than in male rats (based on the NK cell activity).

CONCLUSION

Early-life exposure to 4-NP has been shown to induce gender-specific developmental immunotoxicity in rats, with female pups exhibiting greater sensitivity. And developmental immunotoxicity may serve as a more sensitive indicator for the risk assessment of 4-NP. Th17/Treg balance may be interrupted through JNK/STAT pathway by 4-NP exposure, which needs to be further investigated.

Verteporfin-Mediated In Situ Nanovaccine Based on Local Conventional-Dose Hypofractionated Radiotherapy Enhances Antitumor and Immunomodulatory Effect

In situ radiotherapy is the most successful cytotoxic therapy available for the treatment of solid tumors, while high-dose radiotherapy per fraction is not yet widely and reliably used. To some extent, the major considerations of the disappointing results are on the risk of high-dose irradiation-induced damage to the surrounding normal tissues and the difficulty in distant metastasis control. To break these restraints, a gelatinase-responsive amphiphilic methoxypolyethyleneglycol-PVGLIG-polycaprolactone (mPEG-PVGLIG-PCL) nanoparticles' loading verteporfin (N@VP), a special photosensitizer that can also be excited by X-rays to produce cytotoxic singlet oxygen and greatly enhance radiotherapy efficacy, is prepared in this study. Herein, it is shown that the formed N@VP combined with conventional-dose radiation therapy (RT, 2 Gy (gray, a radiation dose unit)) can realize an antitumor effect no less than high-dose RT (8 Gy) and minimize radiation dose necessary to achieve local tumor control. Moreover, this radiosensitive nanosystem can exert excellent systemic antitumor immunity and abscopal effect, providing a preferable "in situ vaccine" strategy based on conventional-dose RT to achieve efficient systemic management of distant tumor metastasis. When combined with immunotherapy, this novel strategy for radiosensitization results in better immunotherapy sensitivity by stimulating significant immunogenic tumor cell death and synergistic antitumor immune responses.

Recombinant Antithrombin Alleviated Pulmonary Injury and Inflammation in LPS-Induced ARDS by Inhibiting IL17a/NF-κB Signaling

Background

Recombinant antithrombin (rAT) has been shown to protect lungs from ARDS and modulate immune responses, but its anti-inflammatory mechanisms remain unclear. This study aimed to explore the immunomodulatory effects and mechanisms of rAT in LPS-induced ARDS mice.

Methods

ARDS mouse model was established by intraperitoneally administration of 20 mg/kg LPS. After 3 hours of LPS administration, rAT or PBS was injected intravenously. Lung injury, alveolar permeability, serum inflammatory cytokines, immune cell infiltration in lung tissue, and the proportion of Th17 were assessed 36 hours after rAT administration. The functional roles of the differential expressed genes (DEGs), obtained from LPS-induced ARDS mice treated with or without rAT, were analyzed by GO, KEGG and GSEA enrichment analysis. The activation of NF-κB and NLRP3 inflammasome was evaluated by Western blot and immunofluorescence staining.

Results

We found that rAT alleviated lung injury, reduced pulmonary permeability, decreased serum inflammatory cytokines, and suppressed immune cell infiltration and NLRP3 inflammasome activation. Moreover, rAT decreased the proportion of Th17 cells in lung tissues and peripheral blood, downregulated IL17a expression, and inhibited NF-κB signaling pathway in lung tissues. Additionally, the administration of IL-17A diminished the efficacy of rAT in mitigating lung injury, suppressing the immune response, and inhibiting the activation of the NF-κB signaling pathway in LPS-induced ARDS mice.

Conclusion

The findings of this study suggest that rAT alleviates lung injury and suppresses inflammatory responses by inhibiting the IL17a/NF-κB signaling axis, suggesting that rAT may serve as a potential therapeutic agent for mitigating pulmonary inflammation and improving the prognosis of ARDS induced by sepsis. Furthermore, this study provides important research data and theoretical basis for the clinical translation and application of rAT.

Microenvironment-based immunotherapy in oral cancer: a comprehensive review

Oral cancer, a prevalent form of head and neck malignancy, accounts for 4% of global cancer cases. The most common type, oral squamous cell carcinoma (OSCC), has a survival rate of about 50%. Even though emerging molecular therapies show promise for managing oral cancer, current treatments like surgery, radiotherapy, and chemotherapy have significant side effects. In addition, the complex tumor microenvironment (TME), involving the extracellular matrix (ECM) and cells like fibroblasts and stromal cells like immune cells, promotes tumor growth and inhibits immune responses, complicating treatment. Nonetheless, immunotherapy is crucial in cancer treatment, especially in oral cancers. Indeed, its effectiveness lies in targeting immune checkpoints such as PD-1 and CTLA-4 inhibitors, as well as monoclonal antibodies like pembrolizumab and cetuximab, adoptive cell transfer methods (including CAR-T cell therapy), cytokine therapy such as IL-2, and tumor vaccines. Thus, these interventions collectively regulate tumor proliferation and metastasis by targeting the TME through autocrine-paracrine signaling pathways. Immunotherapy indeed aims to stimulate the immune system, leveraging both innate and adaptive immunity to counteract cancer cell signals and promote tumor destruction. This review will explore how the TME controls tumor proliferation and metastasis via autocrine-paracrine signaling pathways. It will then detail the effectiveness of immunotherapy in oral cancers, focusing on immune checkpoints, targeted monoclonal antibodies, adoptive cell transfer, cytokine therapy, and tumor vaccines.

FoxP3-positive T regulatory cells and its effector mechanisms in Crohn's disease: an immunohistochemical and image morphometric analysis on endoscopic mucosal biopsies

OBJECTIVE

Crohn's disease (CD) is an immune inflammatory disorder of the gastrointestinal tract arising from a complex interplay of genetic, environmental, microbiome, and immune factors. Regulatory T cells (Tregs), characterized by FoxP3 expression, are crucial for maintaining immune homeostasis through PD-1/PD-L1 interaction, interleukin (IL)-10 release, and granzyme (GrB) production. This study aimed to elucidate the role of FoxP3 positive (+) Tregs in CD.

METHODS

Segmental colonoscopic biopsies from 46 treatment-naive CD cases (34 adults and 12 children) categorized into noninflamed [n = 32; Nancy histologic index (NHI) 0, 1] and inflamed (n = 100; NHI 2-4) mucosae using NHI. CD4, FoxP3, PD-1, IL-10, and GrB immunoexpression were analyzed by eyeballing and image morphometry. Findings were correlated with activity, granulomas, and skip lesions; and compared with site-matched non-inflammatory bowel disease (IBD) controls (n = 30).

RESULTS

FoxP3+ Tregs, IL-10, PD-1, and GrB expressions were significantly higher in NHI 3-4 mucosae than in NHI 0-1 and controls (P < 0.05). No significant differences were observed between adults and children, whereas those with granulomas had increased expression (P = 0.045). The FoxP3 : CD4 ratio positively correlated with IL-10 (Spearman, r = 0.307, P = 0.002), GrB (r = 0.302, P = 0.002), but not with PD-1 (r = 0.98, P = 0.33).

CONCLUSIONS

Our findings point to the possibility of a qualitative defect in FoxP3+ Tregs in CD. The functional arms of Tregs in CD need to be elucidated further in larger prospective cohorts to validate our observations and pave the way for future immunotherapy.

Immunosenescence in autoimmune diseases

Autoimmune diseases (AIDs) are a group of disorders in which the immune system mistakenly attacks the body's own tissues, characterized by the loss of tolerance to self-antigens and destruction of tissues. Aging is a natural process of physiological decline that also alters the immune system, a condition known as immunosenescence. During immunosenescence, the immune system undergoes various changes, including modifications and antigenicity of self-antigens, abnormalities in the quantity, phenotype, and function of lymphocytes and antibodies, as well as a narrowing of the B and T cell receptor repertoire, changes that may increase susceptibility to AIDs. Additionally, senescent immune cells and the senescence-associated secretory phenotype (SASP) contribute to target organ involvement in AIDs, exacerbating chronic inflammation and tissue damage. Mitochondrial dysfunction and metabolic imbalances in AIDs lead to the accumulation of senescent cells, which act as upstream drivers of immunosenescence. In this review, we summarize the bidirectional relationship between AIDs and immunosenescence, as well as its potential mechanisms. Therapeutic approaches targeting immunosenescence in AIDs remain at an early stage. Strategies aimed at resetting or reversing the aging immune system are expected to become a novel direction in the future.

Role of gut microbiota in thalassemia: a review of therapeutic prospects

In recent years, the study of gut microbiota has gradually become a research hotspot in the field of medicine, as gut microbiota dysbiosis is closely related to various diseases. Thalassemia, as a hereditary hemoglobinopathy, has a complex pathophysiological mechanism, and traditional treatment methods show limited efficacy. With a deeper understanding of the gut microbiome, researchers have begun to focus on its role in the pathogenesis of thalassemia and its therapeutic effects. This article aims to review the role of gut microbiota in thalassemia and its potential therapeutic prospects, analyze the latest research findings, and explore the impact and mechanisms of gut microbiota on patients with thalassemia, with the goal of providing new ideas and directions for future research and clinical treatment of thalassemia.

Targeting HIF-2α in glioblastoma reshapes the immune infiltrate and enhances response to immune checkpoint blockade

Glioblastoma (GBM) is an aggressive primary brain tumor with dismal clinical prognosis and resistance to current therapies. GBM progression is facilitated by the tumor microenvironment (TME), with an immune infiltrate dominated by tumor-associated microglia/macrophages (TAMs) and regulatory T cells (Tregs). The TME is also characterized by hypoxia and the expression of hypoxia-inducible factors (HIFs), with HIF-2α emerging as a potential regulator of tumor progression. However, its role in GBM immunosuppression remains unknown. Here, we investigate HIF-2α and the use of the HIF-2α inhibitor PT2385 to modulate the TME in the immunocompetent GL261 mouse GBM model. PT2385 administration in vivo decreased tumor volume and prolonged survival of tumor-bearing mice, without affecting GL261 viability in vitro. Notably, HIF-2α inhibition alleviated the immunosuppressive TME and synergized with immune checkpoint blockade (ICB) using αPD-1 and αTIM-3 antibodies to promote long-term survival. Comprehensive analysis of the immune infiltrate through single-cell RNA sequencing and flow cytometry revealed that combining PT2385 with ICB reduced numbers of pro-tumoral macrophages and Tregs while increasing numbers of microglia, with a corresponding transcriptional modulation towards an anti-tumoral profile of these TAMs. In vitro, deletion of HIF-2α in microglia impeded their polarization towards a pro-tumoral M2-like profile, and its inhibition impaired Treg migration. Our results show that targeting HIF-2α can switch an immunosuppressive TME towards one that favors a robust and sustained response to ICB based immunotherapy. These findings establish that clinically relevant HIF-2α inhibitors should be explored not only in malignancies with defects in the HIF-2α axis, but also in those exhibiting an immunosuppressive TME that limits immunotherapy responsiveness.

The role of microbiota in the chronic prostatitis/chronic pelvis pain syndrome: a review

Chronic prostatitis/Chronic pelvis pain syndrome (CP/CPPS), a kind of frequent urinary condition among adult males, has caused a lot of inconvenience to patients in life, whose pathogenesis is unclear. Current evidence suggests that it is most likely to be an autoimmune disease. Symbiotic microbes, a highly diverse biological community that harbors trillions of microbes in each region of the human body, have gradually made people realize their important role in immune regulation, material metabolism, and health maintenance. In recent years, increasing studies have shown a connection between microbiota and CP/CPPS. In view of this, we performed this review to summarize the literature pertaining to microbiota and its association with the pathophysiological mechanism of CP/CPPS. In addition, we gleaned the latest progress in the therapeutic strategy of CP/CPPS that related to microbiota regulation in order to offer new perspectives on the management of CP/CPPS.

Prognostic significance of cytokine dysregulation in critically ill COVID-19 patients

BACKGROUND

Understanding the immunopathogenesis of COVID-19 has yielded valuable insights into predicting adverse outcomes-particularly mortality. However, significant gaps persist in our comprehension of the complex interplay among the proposed pathophysiological mechanisms. Here, we aim to investigate the immunological factors associated with mortality in critically ill, unvaccinated COVID-19 patients admitted to the intensive care unit (ICU).

METHODS

We conducted a single-center, prospective study involving 56 unvaccinated COVID-19 patients admitted to the ICU. Plasma cytokine levels at admission were quantified using enzyme-linked immunosorbent assay (ELISA). Continuous variables were presented as median (IQR), and categorical variables as frequencies and percentages. Non-parametric tests assessed group differences. Logistic regression and receiver operating characteristic (ROC) curve analyses identified predictors of mortality, with bootstrapping (1000 re-samplings; 95 % BCa CI) applied for model validation.

RESULTS

Deceased patients exhibited significantly higher levels of interleukin (IL)-1β, IL-2, IL-6, transforming growth factor (TGF)-β, and interferon (IFN)-γ compared to survivors. Conversely, IL-10 and IL-27 were associated with favorable outcomes. Logistic regression modeling identified elevated IL-2 and IFN-γ levels as significant predictors of mortality. Notably, individual ROC curve analyses demonstrated that IL-1β and TGF-β had excellent discriminatory ability for mortality, while IFN-γ, IL-2, and IL-27 showed very good to excellent discriminatory capacity.

CONCLUSION

Our results indicate that distinct cytokine profiles differentiate survivors from non-survivors in critically ill, unvaccinated COVID-19 patients. These findings highlight the importance of cytokine dysregulation in severe COVID-19 cases and suggest potential targets for prognostic approaches. Further research is warranted to validate these results and translate them into effective clinical management strategies.

Shared molecular, cellular, and environmental hallmarks in cardiovascular disease and cancer: Any place for drug repurposing?

Cancer and cardiovascular disease (CVD) are the 2 biggest killers worldwide. Specific treatments have been developed for the 2 diseases. However, mutual therapeutic targets should be considered because of the overlap of cellular and molecular mechanisms. Cancer research has grown at a fast pace, leading to an increasing number of new mechanistic treatments. Some of these drugs could prove useful for treating CVD, which realizes the concept of cancer drug repurposing. This review provides a comprehensive outline of the shared hallmarks of cancer and CVD, primarily ischemic heart disease and heart failure. We focus on chronic inflammation, altered immune response, stromal and vascular cell activation, and underlying signaling pathways causing pathological tissue remodeling. There is an obvious scope for targeting those shared mechanisms, thereby achieving reciprocal preventive and therapeutic benefits. Major attention is devoted to illustrating the logic, advantages, challenges, and viable examples of drug repurposing and discussing the potential influence of sex, gender, age, and ethnicity in realizing this approach. Artificial intelligence will help to refine the personalized application of drug repurposing for patients with CVD. SIGNIFICANCE STATEMENT: Cancer and cardiovascular disease (CVD), the 2 biggest killers worldwide, share several underlying cellular and molecular mechanisms. So far, specific therapies have been developed to tackle the 2 diseases. However, the development of new cardiovascular drugs has been slow compared with cancer drugs. Understanding the intersection between pathological mechanisms of the 2 diseases provides the basis for repurposing cancer therapeutics for CVD treatment. This approach could allow the rapid development of new drugs for patients with CVDs.

T cell related osteoimmunology in fracture healing: Potential targets for augmenting bone regeneration

Last decade has witnessed increasing evidence which highlights the roles of immune cells in bone regeneration. Numerous immune cell types, including macrophages, T cells, and neutrophils are involved in fracture healing by orchestrating a series of events that modulate bone formation and remodeling. In this review, the role of T cell immunity in fracture healing has been summarized, and the modulatory effects of T cell immunity in inflammation, bone formation and remodeling have been highlighted. The review also summarizes the specific roles of different T cell subsets, including CD4+ T cells, CD8+ T cells, regulatory T cells, T helper 17 cells, and γδ T cells in modulating fracture healing. The current therapeutics targeting T cell immunity to enhance fracture healing have also been reviewed, aiming to provide insights from a translational standpoint. Overall, this work discusses recent advances and challenges in the interdisciplinary research field of T cell related osteoimmunology and its implications in fracture healing.

The translational potential of this article

Delayed unions or non-unions of bone fractures remain a challenge in clinical practice. Developing a deep understanding of the roles of immune cells, including T cells, in fracture healing will facilitate the advancement of novel therapeutics of fracture nonunion. This review summarizes the current understanding of different T cell subsets involved in various phases of fracture healing, providing insights for targeting T cells as an alternative strategy to enhance bone regeneration.

Exploring TGF-β Signaling in Cancer Progression: Prospects and Therapeutic Strategies

Cancer persists as a ubiquitous global challenge despite the remarkable advances. It is caused by uncontrolled cell growth and metastasis. The Transforming Growth Factor-beta (TGF-β) signaling pathway is considered a primary regulator of various normal physiological processes in the human body. Recently, factors determining the nature of TGF-β response have received attention, specifically its signaling pathway which can be an attractive therapeutic target for various cancer treatments. The TGF-β receptor is activated by its ligands and undergoes transduction of signals via canonical (SMAD dependent) or non-canonical (SMAD independent) signaling pathways regulating several cellular functions. Furthermore, the cross talk of the TGF-β signaling pathway cross with other signaling pathways has shown the controlled regulation of cellular functions. This review highlights the cross talk between various major signaling pathways and TGF-β. These signaling pathways include Wnt, NF-κB, PI3K/Akt, and Hedgehog (Hh). TGF-β signaling pathway has a dual role at different stages. It can suppress tumor formation at early stages and promote progression at advanced stages. This complex behaviour of TGF-β has made it a promising target for therapeutic interventions. Moreover, many strategies have been designed to control TGF-β signaling pathways at different levels, inhibiting tumor-promoting while enhancing tumor-suppressive effects, each with unique molecular mechanisms and clinical implications. This review also discusses various therapeutic inhibitors including ligand traps, small molecule inhibitors (SMIs), monoclonal antibodies (mAbs), and antisense oligonucleotides which target specific components of TGF-β signaling pathway to inhibit TGF-β signaling and are studied in both preclinical and clinical trials for different types of cancer. The review also highlights the prospect of TGF-β signaling in normal physiology and in the case of dysregulation, TGF-β inhibitors, and different therapeutic effects in cancer therapy along with the perspective of combinational therapies to treat cancer.

Clinical significance of the tumor microenvironment on immune tolerance in gastric cancer

In the realm of oncology, the tumor microenvironment (TME)-comprising extracellular matrix components, immune cells, fibroblasts, and endothelial cells-plays a pivotal role in tumorigenesis, progression, and response to therapeutic interventions. Initially, the TME exhibits tumor-suppressive properties that can inhibit malignant transformation. However, as the tumor progresses, various factors induce immune tolerance, resulting in TME behaving in a state that promotes tumor growth and metastasis in later stages. This state of immunosuppression is crucial as it enables TME to change from a role of killing tumor cells to a role of promoting tumor progression. Gastric cancer is a common malignant tumor of the gastrointestinal tract with an alarmingly high mortality rate. While chemotherapy has historically been the cornerstone of treatment, its efficacy in prolonging survival remains limited. The emergence of immunotherapy has opened new therapeutic pathways, yet the challenge of immune tolerance driven by the gastric cancer microenvironment complicates these efforts. This review aims to elucidate the intricate role of the TME in mediating immune tolerance in gastric cancer and to spotlight innovative strategies and clinical trials designed to enhance the efficacy of immunotherapeutic approaches. By providing a comprehensive theoretical framework, this review seeks to advance the understanding and application of immunotherapy in the treatment of gastric cancer, ultimately contributing to improved patient outcomes.

Cryoablation-induced modulation of Treg cells and the TGF-β pathway in lung adenocarcinoma: implications for increased antitumor immunity

BACKGROUND

Cryoablation plays a key role in the comprehensive management of lung adenocarcinoma, characterized by its ability to activate antitumor immunity. This study aimed to explore the impact of cryoablation on the local immune microenvironment, focusing on regulatory T cells (Tregs) and the TGF-β pathway.

METHODS

Single-cell sequencing was employed to identify differences in immune cell populations and related pathway expression between lung adenocarcinoma tissues and adjacent noncancerous tissues. Prospective observations of changes in Tregs in the peripheral blood pre- and post-cryoablation for lung adenocarcinoma were conducted at Dongfang Hospital, Beijing University of Chinese Medicine. Bulk RNA-seq analysis of mouse tumor tissues was performed to predict the potential mechanisms underlying cryoablation-induced antitumor immunity. Finally, these predictions were validated through in vitro and in vivo experiments employing cell cryoablation and mouse subcutaneous tumor transplantation models.

RESULTS

Single-cell RNA sequencing analysis revealed intricate interactions between Tregs subpopulations and the regulation of the immune response in lung adenocarcinoma, highlighting the involvement of the TGF-β pathway. A significant decrease in the level of Tregs was noted at 30 days post-cryoablation compared to pre-surgical and 3-day post-surgery levels. The cellular and murine cryoablation models validated the inhibitory effect of cryoablation on Tregs and its potential to stimulate antitumor immunity. Additionally, the results of bulk RNA-seq demonstrated the role of cryoablation in regulating postoperative immunity via the TGF-β pathway. Cryoablation decreased the expression levels of TGF-β1, suppressed the phosphorylation of Smad2 and Smad3, and downregulated the expression of FOXP3, thereby inhibiting the conversion of CD4 + T cell precursors into Tregs. Moreover, cryoablation enhanced the expression of interferon-gamma (IFN-γ), thereby promoting its antitumor activity.

CONCLUSIONS

This study revealed the effective modification of the lung adenocarcinoma microenvironment by cryoablation through the suppression of Tregs and activation of antitumor immunity via the TGF-β pathway. These findings hold implications for optimizing cryoablation-based therapies and guiding future clinical trials on lung adenocarcinoma treatment.

TRIAL REGISTRATION

This trial was registered with the Chinese Clinical Trial Registry (Chictr.org.cn, ChiCTR2000038580, Sep 24, 2020).

Role of CD4+ T cell-derived cytokines in the pathogenesis of uveitis

Uveitis refers to a diverse group of inflammatory diseases that affecting the uveal tract, comprising the iris, ciliary body, and choroid, with potential repercussions ranging from visual impairment to blindness. The role of autoimmunity in uveitis etiology is complex and still under investigation. CD4+ T cells intricately regulate immune responses in uveitis through their diverse subtypes: Th1, Th2, Th17, Treg (T regulatory), and Tfh (follicular T helper) cells. Each T cell subtype secretes specific cytokines with either pathogenic or protective implications in uveitis. Th1 cells, characterized by IFN-γ secretion and T-bet expression, drive type 1 immune responses against intracellular pathogens. Conversely, Th2 cells, which produce interleukin (IL)-4, IL-5, and IL-13 and express the transcription factor GATA3, mediate type 2 immune responses to larger extracellular threats like helminths. Th17 cells, generating IL-17 and IL-22 and controlled by RORγt, engage in type 3 immune responses against select pathogens. Tfh cells, releasing IL-21 and governed by Bcl6, aid B cell antibody production. Conversely, Tregs, identified by Foxp3, exert regulatory functions in immune homeostasis. This review delves into the roles of CD4+ T cell-derived cytokines in uveitis, emphasizing their intricate involvement in disease progression and resolution. Insight into these mechanisms might guide therapeutic approaches targeting CD4+ T cell responses in uveitis management.

Extracellular Matrix-Inspired Dendrimer Nanogels Encapsulating Cyclophosphamide for Systemic Sclerosis Treatment

Cyclophosphamide has a certain therapeutic effect on treating systemic sclerosis (SSc), while difficulties exist in controlling severe systematic side effects and enhancing targeting capacity. Here, inspired from the natural extracellular matrix composition, we propose a cyclophosphamide-encapsulated nanogel based on dendritic polymers polyamidoamine (PAMAM) for SSc treatment. We combine bovine serum albumin and generation 5 (G5) PAMAM dendrimers with polyphenol modification to obtain nanogels featured with antioxidant and anti-inflammatory effects. The nanogels can possess excellent biocompatibility and prevent fibroblasts from oxidative stress damage and TGF-β-mediated activation. Furthermore, in the bleomycin-induced SSc mouse model, dendrimer nanogels encapsulating cyclophosphamide also exhibit the ability to attenuate fibrosis by modulating immunity, suppressing inflammation, and reducing collagen synthesis. These findings underscore the value of this dendritic polymer nanogel in the treatment of chronic SSc, indicating its broader potential for clinical applications.

Regenerative Functions of Regulatory T Cells and Current Strategies Utilizing Mesenchymal Stem Cells in Immunomodulatory Tissue Regeneration

BACKGROUND

Regulatory T cells (Tregs) are essential for maintaining immune homeostasis and facilitating tissue regeneration by fostering an environment conducive to tissue repair. However, in damaged tissues, excessive inflammatory responses can overwhelm the immunomodulatory capacity of Tregs, compromising their functionality and potentially hindering effective regeneration. Mesenchymal stem cells (MSCs) play a key role in enhancing Treg function. MSCs enhance Treg activity through indirect interactions, such as cytokine secretion, and direct interactions via membrane proteins.

METHODS

This review examines the regenerative functions of Tregs across various tissues, including bone, cartilage, muscle, and skin, and explores strategies to enhance Treg functionality using MSCs. Advanced techniques, such as the overexpression of relevant genes in MSCs, are highlighted for their potential to further enhance Treg function. Additionally, emerging technologies utilizing extracellular vesicles (EVs) and cell membrane-derived vesicles derived from MSCs offer promising alternatives to circumvent the potential side effects associated with live cell therapies. This review proposes approaches to enhance Treg function and promote tissue regeneration and also outlines future research directions.

RESULTS AND CONCLUSION

This review elucidates recent technological advancements aimed at enhancing Treg function using MSCs and examines their potential to improve tissue regeneration efficiency.

Interaction between Th17 and central nervous system in multiple sclerosis

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Cannabinoid receptor 2 selective agonist ameliorates adjuvant-induced arthritis by modulating the balance between Treg and Th17 cells

Background

Adjuvant-induced arthritis (AIA) serves as a classic model for rheumatoid arthritis (RA), typified by inflammatory cell infiltration and joint damage. This study explores the therapeutic efficacy of HU-308, a CB2 receptor-specific agonist, on inflammation and immune balance in AIA.

Methods

AIA was induced in mice by CFA injection. AIA mice were treated with HU-308 or vehicle, and effects on paw swelling, spleen index, histopathology, and immune cell profiles were evaluated. Flow cytometry, in vitro differentiation assays, and Western blot analysis were performed to examine Th17 and Treg cells, as well as signaling pathways involved in their differentiation.

Results

HU-308 reduced paw swelling, lowered spleen index, and preserved joint integrity in AIA mice, mitigating inflammatory cell infiltration and bone erosion. Flow cytometry revealed that HU-308 restored the Th17/Treg imbalance in AIA, decreasing Th17 cell frequency and enhancing Treg cell infiltration. In vitro assays confirmed HU-308s role in promoting Treg differentiation and inhibiting Th17 polarization. Western blot analysis indicated that HU-308 modulated immune balance through the JAK/STAT5 and TGF-β/SMAD signaling pathways, increasing Foxp3 and TGF-β expression.

Conclusion

HU-308 demonstrates significant anti-inflammatory effects in AIA by restoring Th17/Treg balance and reducing joint damage. The findings indicate that HU-308 holds potential as an immunomodulatory agent for RA, providing valuable insights into CB2-mediated therapeutic strategies for autoimmune diseases.

Cell Homing Strategies in Regenerative Endodontic Therapy

Cell homing, a process that leverages the body's natural ability to recruit cells and repair damaged tissues, presents a promising alternative to cell transplantation methods. Central to this approach is the recruitment of endogenous stem/progenitor cells-such as those from the apical papilla, bone marrow, and periapical tissues-facilitated by chemotactic biological cues. Moreover, biomaterial scaffolds embedded with signaling molecules create supportive environments, promoting cell migration, adhesion, and differentiation for the regeneration of the pulp-dentin complex. By analyzing in vivo animal studies using cell homing strategies, this review explores how biomolecules and scaffold materials enhance the recruitment of endogenous stem cells to the site of damaged dental pulp tissue, thereby promoting repair and regeneration. It also examines the key principles, recent advancements, and current limitations linked to cell homing-based regenerative endodontic therapy, highlighting the interplay of biomaterials, signaling molecules, and their broader clinical implications.

FOXP3, IL-35, and PD-L1 in intra- and peritumoral lymphocytic infiltrate of cutaneous melanomas as an important part of antitumor immunity

BACKGROUND

The tumor microenvironment is a significant mediator enabling tumor growth and progression. Tumor-infiltrating lymphocytes (TILs) are an important component of this but tumor cells develop mechanisms by which they can escape the action of the immune system. Immunosuppressive mechanisms cooperate with each other and involve cells of the immune system, the tumor microenvironment itself, chemokines and cytokines. In this study, we examined the FOXP3+, IL-35+, and PD-L1+ lymphocytes in tumor tissues as they are contributing to immunosuppression in some tumors, including melanoma. Such cells are also associated with tumor progression, early metastasis, and prognosis.

METHODS AND RESULTS

In this study, 95 cutaneous melanomas and 25 melanocytic nevi as a control group were examined by immunohistochemistry for FOXP3+, IL-35+, and PD-L1+ lymphocytes. Melanomas were divided into four groups according to the TNM classification: pT1 (35), pT2 (21), pT3 (21), and pT4 (18). PD-L1+ lymphocytes were enriched in pT3- and pT4-stage melanomas, especially in the periphery of the lesions (P<0.001). The number of FOXP3+ lymphocytes was positively correlated with the stage of the disease, especially in the center of the tumors (P<0.001). Likewise, IL-35+ lymphocytes (P<0.001) were enriched with the stage of the tumor.

CONCLUSION

This article demonstrates that the immunosuppressive environment develops in proportion to the stage of the melanoma. The most significant changes are found at the tumor periphery, confirming the heterogeneity of the tumor stroma which is more pronounced in more advanced tumors and which may contribute to the greater aggressiveness in these peripheral zones.

Exploring the Underlying Mechanism of Weiling Decoction Alleviates Cold-Dampness Diarrhea Based on Network Pharmacology, Transcriptomics, Molecular Docking and Experimental Validation

Background: Cold-dampness diarrhea (CDD) is a common gastrointestinal disorder in children, characterized by diarrhea and intestinal barrier dysfunction. Weiling decoction (WLD) is frequently used in clinical practice to treat CDD, a condition triggered by multiple factors. However, the molecular mechanisms underlying its therapeutic effects remain poorly understood. Objectives: This study aimed to evaluate the efficacy of WLD in treating CDD and to elucidate its potential mechanisms. Methods: UPLC-HRMS/MS was employed to identify the chemical constituents of WLD and the absorption components in the plasma of WLD-treated rats. Additionally, a rat model of CDD was established to assess the therapeutic effects of WLD through a comprehensive approach. To elucidate the molecular mechanisms underlying these effects, network pharmacology and transcriptomic analyses were performed to identify potential signaling pathways associated with CDD alleviation. Molecular docking and flow cytometry assays were subsequently utilized to validate the identified signaling pathways. Results: A total of 223 chemical components were detected in WLD, and 49 absorption components were identified in the plasma of WLD-treated rats by UPLC-HRMS/MS. WLD treatment significantly alleviated the symptoms of CDD, reduced intestinal damage, and diminished the inflammatory response. Additionally, WLD influenced key genes in immune-related pathways. Molecular docking revealed strong binding affinities between the main components of WLD and key targets within these pathways. Flow cytometry, along with the analysis of inflammatory cytokines and transcription factors, demonstrated that WLD modulated the balance between Th1/Th2 and Th17/Treg cell populations. Conclusions: This study provides the first evidence that WLD alleviates CDD by regulating the balance between Th1/Th2 and Th17/Treg cell populations. These findings offer a theoretical basis for future investigations into the therapeutic potential of WLD in the treatment of CDD.

Distinct CD8+ T-cell types Associated with COVID-19 Severity in Unvaccinated HLA-A2+ Patients

Although emerging data have revealed the critical role of memory CD8+ T cells in preventing and controlling SARS-CoV-2 infection, virus-specific CD8+ T-cell responses against SARS-CoV-2 and its memory and innate-like subsets in unvaccinated COVID-19 patients with various disease manifestations in an HLA-restricted fashion remain to be understood. Here, we show the strong association of protective cellular immunity with mild COVID-19 and unique cell types against SARS-CoV-2 virus in an HLA-A2 restricted manner. ELISpot assays reveal that SARS-CoV-2-specific CD8+ T-cell responses in mild COVID-19 patients are significantly higher than in severe patients, whereas neutralizing antibody responses against SARS-CoV-2 virus significantly correlate with disease severity. Single-cell analyses of HLA-A2-restricted CD8+ T cells, which recognize highly conserved immunodominant SARS-CoV-2-specific epitopes, demonstrate divergent profiles in unvaccinated patients with mild versus severe disease. CD8+ T-cell types including cytotoxic KLRB1 + CD8αα cells with innate-like T-cell signatures, IFNG hi ID3 hi memory cells and IL7R + proliferative stem cell-like memory cells are preferentially observed in mild COVID-19, whereas distinct terminally-differentiated T-cell subsets are predominantly detected in severe COVID-19: highly activated FASL hi T-cell subsets and early-terminated or dysfunctional IL4R + GATA3 + stem cell-like memory T-cell subset. In conclusion, our findings suggest that unique and contrasting SARS-CoV-2-specific CD8+ T-cell profiles may dictate COVID-19 severity.

Serum Cystatin S (CST4): A Novel Prognostic Marker for Gastric Cancer

Background

Serum Cystatin S (CST4), a secretory protein that inhibits cellular matrix degradation, significantly influences the tumor microenvironment and tumor progression. However, the prognostic value of serum CST4 in gastric cancer (GC) remains unclear. This study aims to explore serum CST4's utility in GC prognostic assessment.

Methods

A cohort of 334 patients with GC who underwent radical gastrectomy was assessed. Preoperative serum CST4 levels were measured alongside traditional tumor markers, correlating with clinical data and patient outcomes. The cohort was divided into training and test sets at a ratio of 3:1 for Cox regression analyses, which identified CST4 as an independent risk factor for overall survival (OS) and disease-free survival (DFS). A prognostic model was developed, validated with calibration curves, and its predictive value was evaluated using receiver operating characteristic (ROC) curves. In addition, CST4 expression was correlated with immune cell infiltration using data from The Cancer Genome Atlas (TCGA). Patients were stratified by median CST4 levels, and Kaplan-Meier curves for OS and DFS were plotted.

Results

Cystatin S was confirmed as an independent risk factor for OS and DFS. Integrating CST4 with traditional markers and TNM pathological staging significantly enhanced the predictive value for prognosis. Cystatin S's impact on tumor progression is likely mediated through modulation of the immune microenvironment, including immune suppression and evasion.

Conclusion

Cystatin S is an effective biomarker for GC prognostic assessment, assisting in the evaluation of prognosis and the selection of treatment strategies for patients with GC.

Associations of Th1, Th2, Th17, and Treg cell levels and imbalance with recurrent spontaneous abortion: A meta-analysis

OBJECTIVE

Abnormal levels and imbalances of T cell subsets are common in recurrent spontaneous abortion (RSA) patients, but most studies have small sample sizes, and comprehensive evaluations are lacking. Therefore, this meta-analysis aimed to comprehensively investigate T cell subsets and their ratios in RSA patients.

METHODS

Four databases (PubMed, EMBASE, Web of Science, and Cochrane Library databases) were searched until 10 January 2024. T helper 1 (Th1), Th2, Th1/Th2 ratio, Th17, regulatory T (Treg), Treg/Th17 ratio, and the correlation between Th17 and Treg were considered endpoint indexes.

RESULTS

Twenty-six studies involving 1143 RSA women (RSA group) and 863 healthy women (healthy control group) were included. Th1 (standardized mean difference [SMD] = 0.603%; 95% confidence intervals [CI]: 0.406%, 0.800%; p < 0.001), Th1/Th2 ratio (SMD = 0.838; 95% CI: 0.364, 1.312; p = 0.001), and Th17 (SMD = 1.047%; 95% CI: 0.734%, 1.360%; p < 0.001) increased; Th2 (SMD = -0.719%; 95% CI: -1.263%, -0.174%; p = 0.010), Treg (SMD = -1.176%; 95% CI: -1.755%, -0.596%; p < 0.001) and Treg/Th17 ratio (SMD = -0.978; 95% CI: -1.576, -0.381; p = 0.001) reduced in RSA group versus healthy control group. Th17 were inversely correlated with Treg in RSA patients (Correlation coefficient = -0.488; 95% CI: -0.726, -0.145; p = 0.019). The risk of bias was relatively low. There was no publication bias for Th1, Th2, or Th1/Th2 ratio; publication biases for other outcomes were corrected by the trim-and-fill method. Sensitivity analyses showed relatively high robustness.

CONCLUSION

Th1, Th1/Th2 ratio, and Th17 are elevated, while Th2, Treg, and Treg/Th17 ratio are reduced in RSA patients. Meanwhile, Th17 was inversely correlated with Treg in these patients.

The 'Treg paradox' in inflammatory arthritis

Classic regulatory T (Treg) cells expressing CD4 and the hallmark transcription factor FOXP3 are integral to the prevention of multi-system autoimmunity. However, immune-mediated arthritis is often associated with increased numbers of Treg cells in the inflamed joints. To understand these seemingly conflicting observations, which we collectively describe as 'the Treg paradox', we provide an overview of Treg cell biology with a focus on Treg cell heterogeneity, function and dysfunction in arthritis. We discuss how the inflamed environment constrains the immunosuppressive activity of Treg cells while also promoting the differentiation of TH17-like Treg cell, exTreg cell (effector T cells that were formerly Treg cells), and osteoclastogenic Treg cell subsets that mediate tissue injury. We present a new framework to understand Treg cells in joint inflammation and define potential strategies for Treg cell-directed interventions in human inflammatory arthritis.

3-Bromo-4,5-dihydroxybenzaldehyde Attenuates Allergic Contact Dermatitis by Generating CD4+Foxp3+ T cells

BACKGROUND/AIM

Regulatory T cells (Tregs) play a crucial role in inflammatory responses by regulating the activity of various immune cells. M2 macrophages induced by IL-10 and TGF-β exhibit anti-inflammatory functions and induce Treg differentiation. Although the beneficial effects of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) on various diseases have been widely reported, the mechanisms, through which it alleviates allergic contact dermatitis (ACD) via Tregs and macrophages, are not well understood. Therefore, this study aimed to explore whether BDB suppresses ACD and induces Treg generation.

MATERIALS AND METHODS

Mice were sensitized with 1% dinitrochlorobenzene (DNCB), followed by the application of 0.3% DNCB to their ears every 3 days for 31 days. BDB (100 mg/kg) was administered orally once daily throughout the 31 days. Cytokine and transcription factor expression were analyzed via real-time PCR and western blotting, while CD4+Foxp3+ T cell differentiation and T cell proliferation were evaluated using flow cytometry.

RESULTS

BDB exhibited therapeutic efficacy in mice with ACD. In this study, the administration of BDB promoted the upregulation of transforming growth factor beta (TGF-β)-dependent CD4+Foxp3+ T cells. BDB elicited T cell hypo-responsiveness and suppressed the expression of cytokines related to the Th1, Th2, and Th17 cell subsets. BDB-M2 macrophages directly mediated the differentiation of CD4+Foxp3+ T cells from CD4+ T cells and concurrently suppressed the proliferation of CD4+ T cells.

CONCLUSION

BDB augments M2 macrophage function and induction of Tregs confers effective protection against ACD in mice. Consequently, BDB may represent a promising therapeutic approach for the treatment of inflammatory skin diseases.

Gut microbiota contributes to the intestinal and extraintestinal immune homeostasis by balancing Th17/Treg cells

Gut microbiota is generally considered to play an important role in host health due to its extensive immunomodulatory activities. Th17 and Treg cells are two important CD4+ T cell subsets involved in immune regulation, and their imbalance is closely tied to many immune diseases. Recently, abundant researches have highlighted the importance of gut microbiota in supporting intestinal and extraintestinal immunity through the balance of Th17 and Treg cells. Here, we presented a comprehensive review of these findings. This review first provided an overview of gut microbiota, along with Th17/Treg cell differentiation and cytokine production. Subsequently, the review summarized the regulatory effects of gut microbiota (in terms of species, components, and metabolites) on the Th17/Treg cell balance in the local intestines and extraintestinal organs, such as lung, liver, brain, kidney, and bone. Specifically, the Th17 and Treg cells that can be modulated by gut microbiota originate not only from the gut and extraintestinal organs, but also from peripheral blood and spleen. Then, the microbial therapeutics, including probiotics, prebiotics, postbiotics, and fecal microbiota transplantation (FMT), were also reviewed because of their therapeutic potentials in addressing intestinal and extraintestinal diseases via the Th17/Treg axis. Finally, the review discussed the clinical applications and future study prospects of microbial therapeutics by targeting the Th17/Treg cell balance. In conclusion, this review focused on elucidating the regulatory effects of gut microbiota in balancing Th17/Treg cells to maintain intestinal and extraintestinal immune homeostasis, contributing to the further development and promotion of microbial therapeutics.

Copper chelation redirects neutrophil function to enhance anti-GD2 antibody therapy in neuroblastoma

Anti-disialoganglioside (GD2) antibody therapy has provided clinical benefit to patients with neuroblastoma however efficacy is likely impaired by the immunosuppressive tumor microenvironment. We have previously defined a link between intratumoral copper levels and immune evasion. Here, we report that adjuvant copper chelation potentiates anti-GD2 antibody therapy to confer durable tumor control in immunocompetent models of neuroblastoma. Mechanistic studies reveal copper chelation creates an immune-primed tumor microenvironment through enhanced infiltration and activity of Fc-receptor-bearing cells, specifically neutrophils which are emerging as key effectors of antibody therapy. Moreover, we report copper sequestration by neuroblastoma attenuates neutrophil function which can be successfully reversed using copper chelation to increase pro-inflammatory effector functions. Importantly, we repurpose the clinically approved copper chelating agent Cuprior as a non-toxic, efficacious immunomodulatory strategy. Collectively, our findings provide evidence for the clinical testing of Cuprior as an adjuvant to enhance the activity of anti-GD2 antibody therapy and improve outcomes for patients with neuroblastoma.

Immunomodulatory effect of mesenchymal stem cells-derived extracellular vesicles to modulate the regulatory T cells and Th1/Th2 imbalance in peripheral blood mononuclear cells of patients with allergic rhinitis

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have shown promising immunomodulatory capabilities for a variety of clinical conditions. However, the potential regulatory mechanisms of MSC-EVs in allergic rhinitis (AR) remain unexplored. The present study was designed to investigate the immunomodulatory effect of MSC-EVs in patients with AR. Peripheral blood mononuclear cells (PBMCs) were isolated from AR patients. The number of peripheral CD4+Foxp3+IL-17+, CD4+Foxp3+IL-17- and CD4+Foxp3-IL-17+ T cells in healthy controls and AR patients were evaluated using flow cytometry. Therapeutic effect of MSC-EVs was determined by detecting IFN-γ, IL-4, IL-17 and IL-10 cytokines in supernatant by ELISA and flow cytometry. The mean fluorescence intensity (MFI) was calculated in PBMCs for IL-10, IL-17 and TGF-β on T cells after MSC-EVs treatment. Bioinformatic analysis of microRNA was performed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. CD4+Foxp3+IL-17+ T cells expression in PBMCs was higher in the AR group and the balance of Treg/Th17 was tilted towards Th17 cells. Supernatant from AR patients revealed that MSC-EVs treatment upregulated IL-10 and IFN-γ, and downregulated IL-4 and IL-17. EVs treatment effectively re-established Th1(CD4+IFN-γ+cells)/Th2(CD4+IL-4+cells) balance, reduced CD4+IL-17+ and increased CD4+IL-10+ and CD4+TGF-β+ cells. The MFI of IL-10 and TGF-β in CD4+CD25+CD127- T cells were higher, whereas lower levels of IL-17 were observed. Bioinformatic analysis revealed that the TGF-β, Wnt signalling pathways and STAT5 transcription factor might mechanistically support the immunomodulatory effect of MSC-EVs. This study presents the immunomodulatory effect of MSC-EVs in PBMCs from AR patients. The results provide a new therapeutic strategy for AR.

The active form of vitamin D (calcitriol) promotes CXCR5 expression during follicular helper T cell differentiation

Follicular helper T (Tfh) cells promote B cell differentiation and antibody production in the B cell follicles of secondary lymphoid organs. Tfh cells express their signature transcription factor BCL6, interleukin (IL)-21, and surface molecules including inducible T cell costimulator (ICOS), programmed cell death-1 (PD-1), and C-X-C motif chemokine receptor 5 (CXCR5). Migration of Tfh cells to B cell follicles largely depends on the CXCR5 expression induced by interactions with antigen-presenting dendritic cells in the T cell area. How Tfh cells acquire sufficient levels of CXCR5 expression, however, has remained unclear. Using our in vitro culture system to generate CXCR5low Tfh-like cells from naive CD4+ T cells with IL-6 in the absence of other cell types, we found that the active form of vitamin D, calcitriol, markedly enhanced CXCR5 expression after the release from persistent T cell receptor (TCR) stimulation. CH-223191, an aryl hydrocarbon receptor antagonist, further enhanced CXCR5 expression. IL-12 but not IL-4, in place of IL-6, also supported calcitriol to enhance CXCR5 expression even before the release from TCR stimulation, whereas the cell viability sharply decreased after the release. The Tfh-like cells generated with IL-6 and calcitriol exhibited chemotaxis toward C-X-C motif chemokine ligand 13 (CXCL13), expressed IL-21, and helped B cells to produce IgG antibodies in vitro more efficiently than Tfh-like cells generated without added calcitriol. Calcitriol injections into antigen-primed mice increased the proportion of CXCR5+PD-1+CD4+ cells in their lymphoid organs, and enhanced T cell entry into B cell follicles. These results suggest that calcitriol promotes CXCR5 expression in developing Tfh cells and regulates their functional differentiation.

Alloimmune Causes of Recurrent Pregnancy Loss: Cellular Mechanisms and Overview of Therapeutic Approaches

Recurrent pregnancy loss (RPL) is a complex early pregnancy complication affecting 1-2% of couples and is often linked to immune dysfunction. Aberrations in T and B cell subpopulations, as well as natural killer (NK) cell activity, are particularly influential, with studies showing that abnormal NK cell activation and imbalances in T and B cell subtypes contribute to immune-mediated miscarriage risk. Successful pregnancy requires a tightly regulated balance between pro-inflammatory and anti-inflammatory immune responses. In the early stages, inflammation supports processes such as trophoblast invasion and spiral artery remodeling, but this must be tempered to prevent immune rejection of the fetus. In this review, we explore the underlying immune mechanisms of RPL, focusing on how dysregulated T, B, and NK cell function disrupts maternal tolerance. Specifically, we discuss the essential role of uterine NK cells in the early stages of vascular remodeling in the decidua and regulate the depth of invasion by extravillous trophoblasts. Furthermore, we focus on the delicate Treg dynamics that enable the maintenance of optimal immune homeostasis, where the balance, and not only the quantity of Tregs, is crucial for fostering maternal-fetal tolerance. Other T cell subpopulations, such as Th1, Th2, and Th17 cells, also contribute to immune imbalance, with Th1 and Th17 cells promoting inflammation and potentially harming fetal tolerance, while Th2 cells support immune tolerance. Finally, we show how changes in B cell subpopulations and their functions have been associated with adverse pregnancy outcomes. We further discuss current therapeutic strategies aimed at correcting these immune imbalances, including intravenous immunoglobulin (IVIg), glucocorticoids, and TNF-α inhibitors, examining their efficacy, challenges, and potential side effects. By highlighting both the therapeutic benefits and limitations of these interventions, we aim to offer a balanced perspective on clinical applications for women facing immune-related causes of RPL.

Insulin-like growth factor 2 drives fibroblast-mediated tumor immunoevasion and confers resistance to immunotherapy

T cell exclusion is crucial in enabling tumor immune evasion and immunotherapy resistance. However, the key genes driving this process remain unclear. We uncovered a notable increase of insulin-like growth factor 2 (IGF2) in immune-excluded tumors, predominantly secreted by cancer-associated fibroblasts (CAFs). Using mice with systemic or fibroblast-specific deletion of IGF2, we demonstrated that IGF2 deficiency enhanced the infiltration and cytotoxic activity of CD8+ T cells, leading to a reduction in tumor burden. Integration of spatial and single-cell transcriptomics revealed that IGF2 promoted interaction between CAFs and T cells via CXCL12 and programmed death ligand 1 (PD-L1). Mechanistically, autocrine IGF2 activated PI3K/AKT signaling by binding to the IGF1 receptor (IGF1R) on CAFs, which was required for the immunosuppressive functions of CAFs. Furthermore, genetic ablation of IGF2 or targeted inhibition of the IGF2/IGF1R axis with the inhibitor linsitinib markedly boosted the response to immune checkpoint blockade. Clinically, elevated levels of IGF2 in tumors or plasma correlated with an adverse prognosis and reduced efficacy of anti-programmed death 1 treatment. Together, these results highlight the pivotal role of IGF2 in promoting CAF-mediated immunoevasion, indicating its potential as a biomarker and therapeutic target in immunotherapy.

Regulatory T-cells: The Face-off of the Immune Balance

Regulatory T-cells (Tregs) play a crucial role in maintaining immune homeostasis, ensuring a balanced immune response. Tregs primarily operate in an antigen-specific fashion, facilitated by their distinct distribution within discrete niches. Tregs have been studied extensively, from their point of origin in the thymus origin to their fate in the periphery or organs. Signals received from antigen-presenting cells (APCs) stimulate Tregs to dampen inflammation. Almost all tumors are characterized by a pathological abundance of immune suppression in their microenvironment. Conversely, the lack thereof proves detrimental to immunological disorders. Achieving a balanced expression of Tregs in relation to other immune compartments is important in establishing an effective and adaptable immune tolerance towards cancer cells and autoantigens. In the context of cancer, it is essential to decrease the frequency of Tregs to overcome tumor suppression. A lower survival rate is associated with the presence of excessive exhausted effector immune cells and an increased frequency of regulatory cells. However, when it comes to treating graft rejection and autoimmune diseases, the focus lies on immune tolerance and the transfer of Tregs. Here, we explore the complex mechanisms that Tregs use in human disease to balance effector immune cells.

Role of immune dysregulation in peri-implantitis

Peri-implantitis, a complex condition that can lead to dental implant failure, is characterized by inflammatory destruction resulting from immune dysregulation. Oral microbial dysbiosis and foreign body stimulation are the main factors contributing to such dysregulation, impairing immune cell function and triggering an inflammatory response. Immune dysregulation plays a critical role in the pathophysiology of peri-implantitis, impacting the balance of T cell subsets, the production of inflammatory factors, and immune-related molecular signaling pathways. Understanding the relationship between immune dysregulation and peri-implantitis is crucial for developing targeted strategies for clinical diagnosis and individualized treatment planning. This review explores the similarities and differences in the immune microenvironment of oral bacterial infections and foreign body rejection, analyzes the relevant molecular signaling pathways, and identifies new key targets for developing innovative immunotherapeutic drugs and effective and personalized treatment modalities for peri-implantitis. Additionally, it addresses the challenges and potential directions for translating immunotherapy into clinical practice for peri-implantitis, offering insights that bridge the gaps in current literature and pave the way for future research.

Metallothionein-1 mitigates the advancement of osteoarthritis by regulating Th17/Treg balance

Osteoarthritis (OA) is a chronic inflammatory joint disorder characterized by cartilage degradation and bone remodeling. This study investigated the regulatory role of metallothionein 1 (MT1) in modulating immune responses and the balance between regulatory T cells (Treg) and T helper 17 cells (Th17) in OA. Peripheral blood mononuclear cells (PBMCs) from healthy individuals and OA patients were assessed for cytokine expression linked to Treg/Th17 homeostasis. OA was induced in wild-type (WT) and Mt1 knockout (MT1KO) mice via surgical destabilization of the medial meniscus. Clinical scores, pathological features, inflammatory cytokines, and Treg/Th17 balance were evaluated. MT1KO mice showed significantly elevated Mt1, pro-inflammatory cytokines (IL-1, IL-6, TNF-α) and exacerbated OA progression, characterized by increased knee joint diameter, inflammatory infiltration, and cartilage destruction. Mechanistically, disrupted Treg/Th17 balance played a pivotal role in OA exacerbation, with MT1KO promoting Th17 differentiation and reducing Treg populations. Additionally, the compensatory elevation of anti-inflammatory interleukin-10 (IL-10) in OA patients hinted at a nuanced immune regulatory mechanism. The study illuminates intricate interactions involving MT1, Treg/Th17 cells, and pro-inflammatory cytokines in OA pathogenesis, suggesting MT1's potential as a pivotal regulatory factor and a therapeutic target for mitigating immune dysregulation in OA.

Radiation-Induced Intestinal Injury: Molecular Mechanisms and Therapeutic Status

Radiation-induced intestinal injury is one of the most common intestinal complications caused by pelvic and abdominal tumor radiotherapy, severely impacting patients' quality of life. Ionizing radiation, while killing tumor cells, inevitably damages healthy tissue. Radiation-induced enteropathy results from radiation therapy-induced intestinal tissue damage and inflammatory responses. This damage involves various complex molecular mechanisms, including cell apoptosis, oxidative stress, release of inflammatory mediators, disruption of immune responses, and imbalance of intestinal microbiota. A thorough understanding of these molecular mechanisms is crucial for developing effective prevention and treatment strategies.

Research advances in signaling pathways related to the malignant progression of HSIL to invasive cervical cancer: A review

The progression of high-grade squamous intraepithelial lesion (HSIL) to invasive cervical cancer (ICC) is a complex process involving persistent human papillomavirus (HPV) infection and changes in signal transduction regulation, energy and material metabolism, cell proliferation, autoimmune, and other biological process in vaginal microenvironment and immune microenviroment. Signaling pathways are a series of interacting molecules in cells that regulate various physiological functions of cells, such as growth, differentiation, metabolism, and death. In the progression of HSIL to ICC, abnormal activation or inhibition in signaling pathways plays an essensial role. This review presented some signaling pathways related to the malignant progression of HSIL to ICC, including p53, Rb, PI3K/AKT/mTOR, Wnt/β-catenin, Notch, NF-κB, MAPK, TGF-β, JAK-STAT, Hippo, and Hedgehog. The molecular mechanisms involved in the biological process of pathway regulation were also analyzed, in order to illustrate the molecular pathway of HSIL progression to ICC and provide references for the development of more effective prevention and treatment methods.

Myofibroblasts persist through immune privilege mechanisms to mediate oral submucous fibrosis: Uncovering the pathogenesis

Immune privilege is the ability to tolerate foreign antigens without eliciting an inflammatory immune response. Several mechanisms explain a structure's immune privilege status, which is regulated by innate and adaptive immune responses. The role of myofibroblasts in perpetuating fibrosis by acquiring an immune privileged phenotype against the backdrop of oral submucous fibrosis (OSF) is evolving. Myofibroblasts persist through the Fas/FasL autocrine pathway and induce apoptosis in epithelial cells, explaining the juxtaposition of apoptotic cells in areas of fibrosis. However, increased matrix stiffness, in addition to activating TGF-β, reduces Fas surface expression in myofibroblasts, increasing their resistance to apoptosis. The reciprocal amplification loop between the immune checkpoint proteins programmed death-ligand 1 (PD-L1) and TGF-β involves the YAP-TAZ and SMAD2,3 pathways and dramatically enhances profibrotic signalling. Increased matrix stiffness also enhances cMYC expression, which subsequently amplifies PD-L1 levels on myofibroblasts. The increase in PD-L1 on the myofibroblast microengineers the phenotype of CD4+ T cells homing to fibrotic areas by acting on the programmed cell death protein 1 (PD-1) receptor on the T-cell surface, converting these cells from antifibrotic cells to profibrotic cells that produce IL-17A and TGF-β. This manuscript provides mechanistic insight into how myofibroblasts avoid apoptosis in OSFs by evading the immune system. Targeting an immune-privileged phenotype in myofibroblasts with FAS-FASL pathway-dependent characteristics is an ideal strategy for reversing OSF.

Mitigation of checkpoint inhibitor-induced autoimmune hemolytic anemia through modulation of purinergic signaling

ABSTRACT

Immune checkpoint inhibitors (ICPis) have revolutionized cancer immunotherapy but also can induce autoimmune hemolytic anemia (AIHA), a severe disease with high mortality. However, the cellular and molecular mechanism(s) of AIHA secondary to ICPi therapy (ICPi-AIHA) are unclear, other than being initiated through decreased checkpoint inhibition. Herein, we report ICPi-AIHA in a novel mouse model that shows similar characteristics of known human ICPi-AIHA (eg, autoantibodies, hemolysis, and increased mortality). During ICPi-AIHA, there is the simultaneous reduction of 2 regulatory T-cell populations (FoxP3+ and Tr1 [type 1 regulatory cells]) and an increase in inflammatory T helper cell 17 (TH17). Moreover, a novel CD39+CD73-FoxP3-CD25- CD4+ T-cell subset (ie, CD39 single positive [CD39SP]) emerges, and early increases in CD39SP predict AIHA development; CD39 is an ectonuclease that breaks down adenosine triphosphate (ATP). Additionally, we found that boosting ATPase activity by injecting recombinant apyrase mitigates AIHA development and significant CD39SP reductions, both suggesting a functional role for CD39 and demonstrating a novel therapeutic approach. Importantly, CD39SP are detectable in multiple mouse models developing AIHA and in patients with AIHA, demonstrating applicability to idiopathic and secondary AIHA. Highlighting broader autoimmunity relevance, ICPi-treated NZB mice experienced accelerated onset and severity of lupus, including AIHA. Moreover, ICPi treatment of healthy B6 animals led to detectable CD39SP and development of autoantibodies against multiple autoantigens including those on red blood cells and platelets. Together, our findings provide further insight into the cellular and molecular mechanisms of ICPi-AIHA, leading to novel diagnostic and therapeutic approaches with translational potential for use in humans being treated with ICPi.

The multiple roles of interferon regulatory factor family in health and disease

Interferon Regulatory Factors (IRFs), a family of transcription factors, profoundly influence the immune system, impacting both physiological and pathological processes. This review explores the diverse functions of nine mammalian IRF members, each featuring conserved domains essential for interactions with other transcription factors and cofactors. These interactions allow IRFs to modulate a broad spectrum of physiological processes, encompassing host defense, immune response, and cell development. Conversely, their pivotal role in immune regulation implicates them in the pathophysiology of various diseases, such as infectious diseases, autoimmune disorders, metabolic diseases, and cancers. In this context, IRFs display a dichotomous nature, functioning as both tumor suppressors and promoters, contingent upon the specific disease milieu. Post-translational modifications of IRFs, including phosphorylation and ubiquitination, play a crucial role in modulating their function, stability, and activation. As prospective biomarkers and therapeutic targets, IRFs present promising opportunities for disease intervention. Further research is needed to elucidate the precise mechanisms governing IRF regulation, potentially pioneering innovative therapeutic strategies, particularly in cancer treatment, where the equilibrium of IRF activities is of paramount importance.

Ursolic Acid Regulates Immune Balance, Modulates Gut Microbial Metabolism, and Improves Liver Health in Mice

Ursolic acid (UA) has demonstrated significant immunomodulatory and hepatoprotective effects; however, the underlying mechanisms remain unclear. This study aims to analyze the impact of UA on the gut microbiome, metabolome, and liver transcriptome, investigate UA's role in maintaining gut immune homeostasis and liver health, and evaluate the potential contributions of gut microbes and their metabolites to these beneficial effects. Our findings indicate that UA enhances immune balance in the jejunum, fortifies intestinal barrier function, and promotes overall gut health. UA modulates the intestinal microbiota and its metabolic processes, notably increasing the abundance of beneficial bacteria such as Odoribacter and Parabacteroides, along with their metabolites, including ornithine and lactucin. Additionally, UA inhibits the expression of interleukin-1 receptor 1 (IL1R1) and calcium (Ca2+) voltage-gated channel auxiliary subunit beta 2 (CACNB2) while enhancing the synthesis pathways of retinol and ascorbic acid, thereby exerting a protective influence on liver function. In summary, UA enhances intestinal immune homeostasis and promotes liver health, with these advantageous effects potentially mediated by beneficial bacteria (Odoribacter and Parabacteroides) and their metabolites (ornithine and lactucin).

Blocking TGFβR synergistically enhances anti-tumor effects of anti-PD-1 antibody in a mouse model of incomplete thermal ablation

The mechanism of early tumor recurrence after incomplete microwave ablation (iMWA) is poorly understood. The anti-programmed cell death protein 1 (anti-PD-1) monotherapy is reported to be ineffective to prevent the progression of residual tumor resulted from iMWA. Transforming growth factor-β (TGFβ) signaling pathway plays an important role in tumorigenesis and development. We assume blocking transforming growth factor-β receptor (TGFβR) after incomplete iMWA may synergistically enhance the effect of anti-PD-1 antibody to prevent the progression of residual tumor. We construct an iMWA model with mice harboring Hepa1-6 derived xenograft. The Tgfb1 expression and phosphorylated-Smad3 protein expression is upregulated in the residual tumor after iMWA. With the application of TGFβR inhibitor SB431542, the cell proliferation potential, the tumor growth, the mRNA expression of epithelial mesenchymal transition (EMT) markers including Cdh2, and Vim, and cancer stem cell marker Epcam, and the infiltrating Treg cells are reduced in the residual tumor tissue. In addition, iMWA combined with TGFβR blocker and anti-PD-1 antibody further decreases the cell proliferation, tumor growth, expression of EMT markers and cancer stem cell marker, and the infiltrating Treg cells in the residual tumor tissue. Blocking TGFβR may alleviate the pro-tumoral effect of tumor microenvironment thereby significantly prevents the progression of residual tumor tissue. Our study indicates that blocking TGFβR may be a novel therapeutic strategy to enhance the effect of anti-PD-1 antibody to prevent residual hepatocellular carcinoma (HCC) progression after iMWA.

Bioactive sphingolipids as emerging targets for signal transduction in cancer development

Sphingolipids, crucial components of cellular membranes, play a vital role in maintaining cellular structure and signaling integrity. Disruptions in sphingolipid metabolism are increasingly implicated in cancer development. Key bioactive sphingolipids, such as ceramides, sphingosine-1-phosphate (S1P), ceramide-1-phosphate (C1P), and glycosphingolipids, profoundly impact tumor biology. They influence the behavior of tumor cells, stromal cells, and immune cells, affecting tumor aggressiveness, angiogenesis, immune modulation, and extracellular matrix remodeling. Furthermore, abnormal expression of sphingolipids and their metabolizing enzymes modulates the secretion of tumor-derived extracellular vesicles (TDEs), which are key players in creating an immunosuppressive tumor microenvironment, remodeling the extracellular matrix, and facilitating oncogenic signaling within in situ tumors and distant pre-metastatic niches (PMNs). Understanding the role of sphingolipids in the biogenesis of tumor-derived extracellular vesicles (TDEs) and their bioactive contents can pave the way for new biomarkers in cancer diagnosis and prognosis, ultimately enhancing comprehensive tumor treatment strategies.

Immune thrombocytopenia: Pathophysiology and impacts of Romiplostim treatment

Immune thrombocytopenia (ITP) is an autoimmune bleeding disease caused by immune-mediated platelet destruction and decreased platelet production. ITP is characterized by an isolated thrombocytopenia (<100 × 109/L) and increased risk of bleeding. The disease has a complex pathophysiology wherein immune tolerance breakdown leads to platelet and megakaryocyte destruction. Therapeutics such as corticosteroids, intravenous immunoglobulins (IVIg), rituximab, and thrombopoietin receptor agonists (TPO-RAs) aim to increase platelet counts to prevent hemorrhage and increase quality of life. TPO-RAs act via stimulation of TPO receptors on megakaryocytes to directly stimulate platelet production. Romiplostim is a TPO-RA that has become a mainstay in the treatment of ITP. Treatment significantly increases megakaryocyte maturation and growth leading to improved platelet production and it has recently been shown to have additional immunomodulatory effects in treated patients. This review will highlight the complex pathophysiology of ITP and discuss the usage of Romiplostim in ITP and its ability to potentially immunomodulate autoimmunity.

A review of CD4+ T cell differentiation and diversity in dogs

CD4+ T cells are an integral component of the adaptive immune response, carrying out many functions to combat a diverse range of pathogenic challenges. These cells exhibit remarkable plasticity, differentiating into specialized subsets such as T helper type 1 (TH1), TH2, TH9, TH17, TH22, regulatory T cells (Tregs), and follicular T helper (TFH) cells. Each subset is capable of addressing a distinct immunological need ranging from pathogen eradication to regulation of immune homeostasis. As the immune response subsides, CD4+ T cells rest down into long-lived memory phenotypes-including central memory (TCM), effector memory (TEM), resident memory (TRM), and terminally differentiated effector memory cells (TEMRA) that are localized to facilitate a swift and potent response upon antigen re-encounter. This capacity for long-term immunological memory and rapid reactivation upon secondary exposure highlights the role CD4+ T cells play in sustaining both adaptive defense mechanisms and maintenance. Decades of mouse, human, and to a lesser extent, pig T cell research has provided the framework for understanding the role of CD4+ T cells in immune responses, but these model systems do not always mimic each other. Although our understanding of pig immunology is not as extensive as mouse or human research, we have gained valuable insight by studying this model. More akin to pigs, our understanding of CD4+ T cells in dogs is much less complete. This disparity exists in part because canine immunologists depend on paradigms from mouse and human studies to characterize CD4+ T cells in dogs, with a fraction of available lineage-defining antibody markers. Despite this, every major CD4+ T cell subset has been described to some extent in dogs. These subsets have been studied in various contexts, including in vitro stimulation, homeostatic conditions, and across a range of disease states. Canine CD4+ T cells have been categorized according to lineage-defining characteristics, trafficking patterns, and what cytokines they produce upon stimulation. This review addresses our current understanding of canine CD4+ T cells from a comparative perspective by highlighting both the similarities and differences from mouse, human, and pig CD4+ T cell biology. We also discuss knowledge gaps in our current understanding of CD4+ T cells in dogs that could provide direction for future studies in the field.

Tertiary lymphoid structures in diseases: immune mechanisms and therapeutic advances

Tertiary lymphoid structures (TLSs) are defined as lymphoid aggregates formed in non-hematopoietic organs under pathological conditions. Similar to secondary lymphoid organs (SLOs), the formation of TLSs relies on the interaction between lymphoid tissue inducer (LTi) cells and lymphoid tissue organizer (LTo) cells, involving multiple cytokines. Heterogeneity is a distinguishing feature of TLSs, which may lead to differences in their functions. Growing evidence suggests that TLSs are associated with various diseases, such as cancers, autoimmune diseases, transplant rejection, chronic inflammation, infection, and even ageing. However, the detailed mechanisms behind these clinical associations are not yet fully understood. The mechanisms by which TLS maturation and localization affect immune function are also unclear. Therefore, it is necessary to enhance the understanding of TLS development and function at the cellular and molecular level, which may allow us to utilize them to improve the immune microenvironment. In this review, we delve into the composition, formation mechanism, associations with diseases, and potential therapeutic applications of TLSs. Furthermore, we discuss the therapeutic implications of TLSs, such as their role as markers of therapeutic response and prognosis. Finally, we summarize various methods for detecting and targeting TLSs. Overall, we provide a comprehensive understanding of TLSs and aim to develop more effective therapeutic strategies.

Relation of T Cell Profile with Vitamin D Receptor and Vitamin D-Binding Protein Gene Polymorphisms in Atopy

Atopic diseases, including atopic dermatitis (AD) and allergic asthma (AA), are characterized by complex immune responses involving various T cells subsets and their cytokine profiles. It is assumed that single nucleotide polymorphisms (SNPs) in the Vitamin D receptor (VDR) gene and the Vitamin D-binding protein (GC) gene are related to the action of Vitamin D and, consequently, play a role in regulating the immune response. However, there is not enough data to unequivocally support the hypothesis about the relationship between T cells profile and VDR or GC SNPs. Two hundred sixty-six subjects (aged > 18 years) were involved in the study: 100 patients with mild or moderate AD, 85 patients with mild or moderate AA, and 81 healthy individuals. Blood cell counts were determined by standard methods. Flow cytometric analysis was used to evaluate CD4+ T-helper (Th) cell subtypes: Th2, Th1, Th17, and T regulatory (Treg) cells in peripheral blood. Measurements of cytokines, total immunoglobulin E (IgE), and Vitamin D levels in serum were evaluated by ELISA. Significantly higher levels of Th1, Th2, and Th17 cells, along with lower levels of Tregs, were found in patients with atopic diseases compared to healthy individuals. Additionally, higher serum levels of interleukin (IL) 5, IL-17A, and transforming growth factor-β1 (TGF-β1), as well as lower levels of IL-10, were observed in patients with atopic diseases than in control. The study established associations between VDR SNPs and immune profiles: the AA genotype of rs731236 was associated with increased Th2 and Th17 cells and a higher Th1/Th2 ratio; the GG genotype of rs731236 was linked to decreased serum IL-10 and TGF-β1 levels; and the TT genotype of rs11168293 was associated with increased IL-10 levels. Additionally, the GG genotype of GC gene SNP rs4588 was associated with reduced Th2 and Th17 lymphocytes, while the TT genotype of rs4588 was linked to decreased IL-10 levels. Furthermore, the CC genotype of rs7041 was associated with higher levels of Th2, Th17, IL-10, and IL-35, as well as reduced levels of TGF-β1, while the GG genotype of rs3733359 was associated with reduced IL-10 levels. In conclusion, our study demonstrates that the Vitamin D receptor gene single nucleotide polymorphisms rs731236 and rs11168293, along with polymorphisms in the Vitamin D-binding protein gene (rs4588, rs7041, rs3733359), are significantly associated with variations in T cell profiles in atopy. These variations may play a crucial role in promoting inflammation and provide insight into the genetic factors contributing to the pathogenesis of atopy.

Antioxidant and Immunomodulatory Polymer Vesicles for Effective Diabetic Wound Treatment through ROS Scavenging and Immune Modulating

Chronic diabetic wound patients usually show high glucose levels and systemic immune disorder, resulting in high reactive oxygen species (ROS) levels and immune cell dysfunction, prolonged inflammation, and delayed wound healing. Herein, we prepared an antioxidant and immunomodulatory polymer vesicle for diabetic wound treatment. This vesicle is self-assembled from poly(ε-caprolactone)36-block-poly[lysine4-stat-(lysine-mannose)22-stat-tyrosine)16] ([PCL36-b-P[Lys4-stat-(Lys-Man)22-stat-Tyr16]). Polytyrosine is an antioxidant polypeptide that can scavenge ROS. d-Mannose was introduced to afford immunomodulatory functions by promoting macrophage transformation and Treg cell activation through inhibitory cytokines. The mice treated with polymer vesicles showed 23.7% higher Treg cell levels and a 91.3% higher M2/M1 ratio than those treated with PBS. Animal tests confirmed this vesicle accelerated healing and achieved complete healing of S. aureus-infected diabetic wounds within 8 days. Overall, this is the first antioxidant and immunomodulatory vesicle for diabetic wound healing by scavenging ROS and regulating immune homeostasis, opening new avenues for effective diabetic wound healing.