The cytokine milieu in the interplay of pathogenic Th1/Th17 cells and regulatory T cells in autoimmune disease

Single-cell multi-ome and immune profiles of the Inspiration4 crew reveal conserved, cell-type, and sex-specific responses to spaceflight

Spaceflight induces an immune response in astronauts. To better characterize this effect, we generated single-cell, multi-ome, cell-free RNA (cfRNA), biochemical, and hematology data for the SpaceX Inspiration4 (I4) mission crew. We found that 18 cytokines/chemokines related to inflammation, aging, and muscle homeostasis changed after spaceflight. In I4 single-cell multi-omics data, we identified a "spaceflight signature" of gene expression characterized by enrichment in oxidative phosphorylation, UV response, immune function, and TCF21 pathways. We confirmed the presence of this signature in independent datasets, including the NASA Twins Study, the I4 skin spatial transcriptomics, and 817 NASA GeneLab mouse transcriptomes. Finally, we observed that (1) T cells showed an up-regulation of FOXP3, (2) MHC class I genes exhibited long-term suppression, and (3) infection-related immune pathways were associated with microbiome shifts. In summary, this study reveals conserved and distinct immune disruptions occurring and details a roadmap for potential countermeasures to preserve astronaut health.

Mechanic study based on untargeted metabolomics of Pi-pa-run-fei-tang on pepper combined with ammonia induced chronic cough model mice

ETHNOPHARMACOLOGICAL RELEVANCE

Pi-pa-run-fei-tang (PPRFT), a traditional Chinese medicine formula with long-standing history, demonstrated beneficial effect on chronic cough. However, the mechanism underlying efficacy unclear. In current research, we explored the impact and molecular mechanism of chronic cough mouse stimulating with capsaicin combined with ammonia.

AIM OF THE STUDY

To investigate the metabolic modulating effects, and potential mechanisms underlying the therapeutic effect of PPRFT in chronic cough.

MATERIALS AND METHODS

Chronic cough mouse models were created by stimulating mice by capsaicin combined with ammonia. Number of coughs and cough latency within 2 min were recorded. With lung tissue and serum samples collected for histopathology, metabolomics, RT-qPCR, immunohistochemistry, and WB analysis. Lymphocytes were isolated and flow cytometric assays were conducted to evaluate the differentiation between Th17 and Treg cell among CD4+ cells.

RESULTS

Results indicated that PPRFT obviously reduced the number of coughs, prolonged cough latency, reduced inflammatory cell infiltration and lung tissues damage, and decreased the serum level of IL-6, IL-1β, TNF-α, and IL-17 while increasing IL-10 levels. Notably, PPRFT suppressed Th17 cell divergence and promoted Treg cell divergence. Furthermore, serum metabolomic assays showed that 46 metabolites differed significantly between group, with 35 pathways involved. Moreover, mRNA levels of IL-6, NF-κB, IL-17, RORγT, JAK2, STAT3, PI3K and AKT in lung tissues remarkably reduced and mRNA levels of IL-10 and FOXP3 were elevated after PPRFT pretreatment. Additionally, PPRFT treatments decreased the protein levels of IL-6, NF-κB, IL-17, RORγT, p-JAK2, p-STAT3, p-PI3K, and p-AKT and increased the protein levels of IL-10 and FOXP3, but no significantly effects to the levels on JAK2, STAT3, PI3K, and AKT in the lungs.

CONCLUSION

Conclusively, our result suggested the effect with PPRFT on chronic cough may be mediated through IL-6/JAK2/STAT3 and PI3K/AKT/NF-κB pathway, which regulate the differentiation between Th17 and Treg cell. This beneficial effect of PPRFT in capsaicin and ammonia-stimulated chronic cough mice indicates its potential application in treating chronic cough.

Osteoporosis: interferon-gamma-mediated bone remodeling in osteoimmunology

As the world population ages, osteoporosis, the most common disease of bone metabolism, affects more than 200 million people worldwide. The etiology is an imbalance in bone remodeling process resulting in more significant bone resorption than bone remodeling. With the advent of the osteoimmunology field, the immune system's role in skeletal pathologies is gradually being discovered. The cytokine interferon-gamma (IFN-γ), a member of the interferon family, is an important factor in the etiology and treatment of osteoporosis because it mediates bone remodeling. This review starts with bone remodeling process and includes the cellular and key signaling pathways of bone remodeling. The effects of IFN-γ on osteoblasts, osteoclasts, and bone mass are discussed separately, while the overall effects of IFN-γ on primary and secondary osteoporosis are summarized. The net effect of IFN-γ on bone appears to be highly dependent on the environment, dose, concentration, and stage of cellular differentiation. This review focuses on the mechanisms of bone remodeling and bone immunology, with a comprehensive discussion of the relationship between IFN-γ and osteoporosis. Finding the paradoxical balance of IFN-γ in bone immunology and exploring the potential of its clinical application provide new ideas for the clinical treatment of osteoporosis and drug development.

Downregulation of protein phosphatase 2Aα in asthmatic airway smooth muscle

Airway smooth muscle cell (ASM) is renowned for its involvement in airway hyperresponsiveness through impaired ASM relaxation and bronchoconstriction in asthma, which poses a significant challenge in the field. Recent studies have explored different targets in ASM to alleviate airway hyperresponsiveness, however, a sizeable portion of patients with asthma still experience poor control. In our study, we explored protein phosphatase 2 A (PP2A) in ASM as it has been reported to regulate cellular contractility by controlling intracellular calcium ([Ca2+]i), ion channels, and respective regulatory proteins. We obtained human ASM cells and lung tissues from healthy and patients with asthma and evaluated PP2A expression using RNA-Seq data, immunofluorescence, and immunoblotting. We further investigated the functional importance of PP2A by determining its role in bronchoconstriction using mouse bronchus and human ASM cell [Ca2+]i regulation. We found robust expression of PP2A isoforms in human ASM cells with PP2Aα being highly expressed. Interestingly, PP2Aα was significantly downregulated in asthmatic tissue and human ASM cells exposed to proinflammatory cytokines. Functionally, FTY720 (PP2A agonist) inhibited acetylcholine- or methacholine-induced bronchial contraction in mouse bronchus and further potentiated isoproterenol-induced bronchial relaxation. Mechanistically, FTY720 inhibited histamine-evoked [Ca2+]i response and myosin light chain (MLC) phosphorylation in the presence of interleukin-13 (IL-13) in human ASM cells. To conclude, we for the first time established PP2A signaling in ASM, which can be further explored to develop novel therapeutics to alleviate airway hyperresponsiveness in asthma.NEW & NOTEWORTHY This novel study deciphered the expression and function of protein phosphatase 2Aα (PP2Aα) in airway smooth muscle (ASM) during asthma and/or inflammation. We showed robust expression of PP2Aα in human ASM while its downregulation in asthmatic ASM. Similarly, we demonstrated reduced PP2Aα expression in ASM exposed to proinflammatory cytokines. PP2Aα activation inhibited bronchoconstriction of isolated mouse bronchi. In addition, we unveiled that PP2Aα activation inhibits the intracellular calcium release and myosin light chain phosphorylation in human ASM.

Integrating circulating T follicular memory cells and autoantibody repertoires for characterization of autoimmune disorders

Introduction

Autoimmune diseases are heterogeneous and often lack specific or sensitive diagnostic tests. Increased percentages of CD4+CXCR5+PD1+ circulating T follicular helper (cTfh) cells and skewed distributions of cTfh subtypes have been associated with autoimmunity. However, cTfh cell percentages can normalize with immunomodulatory treatment despite persistent disease activity, indicating the need for identifying additional cellular and/or serologic features correlating with autoimmunity.

Methods

The cohort included 50 controls and 56 patients with autoimmune cytopenias, gastrointestinal, pulmonary, and/or neurologic autoimmune disease. Flow cytometry was used to measure CD4+CXCR5+ T cell subsets expressing the chemokine receptors CXCR3 and/or CCR6: CXCR3+CCR6- Type 1, CXCR3-CCR6- Type 2, CXCR3+CCR6+ Type 1/17, and CXCR3- CCR6+ Type 17 T cells. IgG and IgA autoantibodies were quantified using a microarray featuring 1616 full-length, conformationally intact protein antigens. The 97.5th percentile in the control cohort defined normal limits for T cell subset percentages and total number (burden) of autoantibodies.

Results

This study focused on CD4+CXCR5+ T cells because CXCR5 upregulation occurs after cognate T-B cell interactions characteristic of autoimmune diseases. We refer to these cells as circulating T follicular memory (cTfm) cells to acknowledge the dynamic nature of antigen-experienced CXCR5+ T cells, which encompass progenitors of cTfh or Tfh cells as well as early effector memory T cells that have not yet lost CXCR5. Compared to controls, 57.1% of patients had increased CXCR5+CXCR3+CCR6+ cTfm1/17 and 25% had increased CXCR5+CXCR3-CCR6+ cTfm17 cell percentages. Patients had significantly more diverse IgG and IgA autoantibodies than controls and 44.6% had an increased burden of autoantibodies of either isotype. Unsupervised autoantibody clustering identified three clusters of patients with IgG autoantibody profiles distinct from those of controls, enriched for patients with active autoimmunity and monogenic diseases. An increased percentage of cTfm17 cells was most closely associated with an increased burden of high-titer IgG and IgA autoantibodies. A composite measure integrating increased cTfm1/17, cTfm17, and high-titer IgG and/or IgA autoantibodies had 91.1% sensitivity and 90.9% specificity for identifying patients with autoimmunity. Percentages of cTfm1/17 and cTfm17 percentages and numbers of high-titer autoantibodies in patients receiving immunomodulatory treatment did not differ from those in untreated patients, thus suggesting that measurements of cTfm can complement measurements of other cellular markers affected by treatment.

Conclusions

This study highlights two new approaches for assessing autoimmunity: measuring CD4+CXCR5+ cTfm subsets as well as total burden of autoantibodies. Our findings suggest that these approaches are particularly relevant to patients with rare autoimmune disorders for whom target antigens and prognosis are often unknown.

Peripheral blood mononuclear cell transcriptome profile in a clinical trial with subcutaneous, grass pollen allergoid immunotherapy

INTRODUCTION

Allergen-specific immunotherapy (AIT) is the only disease-modifying treatment in allergic airway diseases. Underlying immunological mechanisms and candidate biomarkers, which may be translated into predictive/surrogate measures of clinical efficacy, remain an active area of research. The aim of this study was to evaluate Pollinex Quattro (PQ) Grass AIT induced immunomodulatory mechanisms, based on transcriptome profiling of peripheral blood mononuclear cells.

METHODS

119 subjects with grass pollen induced seasonal allergic rhinitis (SAR) were randomized in a 2:2:1:1 ratio to receive a cumulative dose of PQ Grass as a conventional or extended pre-seasonal regimen, placebo, or placebo with MicroCrystalline Tyrosine. Gene expression analysis was an exploratory endpoint evaluated in a subgroup of 30 subjects randomly selected from the four treatment arms. Samples were collected at three time points: screening (baseline), before the start of the grass pollen season and at the end of the season. This study was funded by the manufacturer of PQ.

RESULTS

Transcriptome analysis demonstrated that the most significant changes in gene expression, for both treatment regimens, were at the end of the grass pollen season, with the main Th1 candidate molecules (IL-12A, IFNγ) upregulated and Th2 signature cytokines downregulated (IL-4, IL-13, IL-9) (p < .05). Canonical pathways analysis demonstrated Th1, Th2, Th17 and IL-17 as the most significantly enriched pathways based on absolute value of activation z-score (IzI score ≥ 2, p < .05). Upstream regulator analysis showed pronounced inhibition of pro-inflammatory allergic molecules IgE, IL-17A, IL-17F, IL-25 (IL-17E) (IzI score ≥ 2, FDR < 0.05) and activation of pro-tolerogenic molecules IL-12A, IL-27, IL-35 (EBI3) at the end of the grass pollen season.

CONCLUSION

Peripheral blood mononuclear cells transcriptome profile showed an inhibition of Th2, Th17 pro-inflammatory allergic responses and immune deviation towards Th1 responses. PQ Grass extended regimen exhibited a superior mechanistic efficacy profile in comparison with PQ conventional regimen.

VXX-401, a novel anti-PCSK9 vaccine, reduces LDL-C in cynomolgus monkeys

Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of disease burden in the world and is highly correlated with chronic elevations of LDL-C. LDL-C-lowering drugs, such as statins or monoclonal antibodies against proprotein convertase subtilisin/kexin type 9 (PCSK9), are known to reduce the risk of cardiovascular diseases; however, statins are associated with limited efficacy and poor adherence to treatment, whereas PCSK9 inhibitors are only prescribed to a "high-risk" patient population or those who have failed other therapies. Based on the proven efficacy and safety profile of existing monoclonal antibodies, we have developed a peptide-based vaccine against PCSK9, VXX-401, as an alternative option to treat hypercholesterolemia and prevent ASCVD. VXX-401 is designed to trigger a safe humoral immune response against PCSK9, resulting in the production of endogenous antibodies and a subsequent 30-40% reduction in blood LDL-C. In this article, VXX-401 demonstrates robust immunogenicity and sustained serum LDL-C-lowering effects in nonhuman primates. In addition, antibodies induced by VXX-401 bind to human PCSK9 with high affinity and block the inhibitory effect of PCSK9 on LDL-C uptake in a hepatic cell model. A repeat-dose toxicity study conducted in nonhuman primates under good laboratory practices toxicity indicated a suitable safety and tolerability profile, with injection site reactions being the main findings. As a promising safe and effective LDL-C-lowering therapy, VXX-401 may represent a broadly accessible and convenient option to treat hypercholesterolemia and prevent ASCVD.

Immune cells in the epithelial immune microenvironment of psoriasis: emerging therapeutic targets

Psoriasis is a chronic autoimmune inflammatory disease characterized by erroneous metabolism of keratinocytes. The development of psoriasis is closely related to abnormal activation and disorders of the immune system. Dysregulated skin protective mechanisms can activate inflammatory pathways within the epithelial immune microenvironment (EIME), leading to the development of autoimmune-related and inflammatory skin diseases. In this review, we initially emphasized the pathogenesis of psoriasis, paying particular attention to the interactions between the abnormal activation of immune cells and the production of cytokines in psoriasis. Subsequently, we delved into the significance of the interactions between EIME and immune cells in the emergence of psoriasis. A thorough understanding of these immune processes is crucial to the development of targeted therapies for psoriasis. Finally, we discussed the potential novel targeted therapies aimed at modulating the EIME in psoriasis. This comprehensive examination sheds light on the intricate underlying immune mechanisms and provides insights into potential therapeutic avenues of immune-mediated inflammatory diseases.

The role of Interleukin-21 in autoimmune Diseases: Mechanisms, therapeutic Implications, and future directions

IL-21 is a multifunctional cytokine that regulates the functional activity of various immune cells. Initial studies have shown that IL-21 can influence the differentiation, proliferation and function of T and B cells, as well as promote the maturation and increase the cytotoxicity of CD8 + T cells and NK cells. During humoral immune responses, IL-21 has significant effects on B cell activation, differentiation and apoptosis. In addition, IL-21 promotes the differentiation of both naive and memory B cells, ultimately leading to the activation of plasma cells. The function of IL-21 in the immune system is complex, as it has the ability to either stimulate or inhibit immune responses. in addition, IL-21 facilitates the differentiation of naive and memory B cells into plasma cells. The functionality of IL-21 in the immune system is diverse, as it has the ability to stimulate or inhibit immune responses. This cytokine has been implicated in several diseases including cancer, allergies and autoimmune diseases. Research has suggested that this cytokine is involved in the development of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. Several studies have suggested that inhibition of IL-21 has a therapeutic effect on autoimmune diseases. Therefore, targeting both the cytokine's receptor and IL-21 in autoimmune diseases may be an effective approach to reduce the severity of the disease or to treat it. This review will examine the biological effects of IL-21 on various immune cells and the role of the cytokine in autoimmune diseases.

Advanced targeted drug delivery by bioengineered white blood cell-membrane camouflaged nanoparticulate delivery nanostructures

Targeted drug delivery has emerged as a pivotal approach within precision medicine, aiming to optimize therapeutic efficacy while minimizing systemic side effects. Leukocyte membrane coated nanoparticles (NPs) have attracted a lot of interest as an effective approach for delivering targeted drugs, capitalizing on the natural attributes of leukocytes to achieve site-specific accumulation, and heightened therapeutic outcomes. An overview of the present state of the targeted medication delivery research is given in this review. Notably, Leukocyte membrane-coated NPs offer inherent advantages such as immune evasion, extended circulation half-life, and precise homing to inflamed or diseased tissues through specific interactions with adhesion molecules. leukocyte membrane-coated NPs hold significant promise in advancing targeted drug delivery for precision medicine. As research progresses, they are anticipated to contribute to improved therapeutic outcomes, enabling personalized and effective treatments for a wide range of diseases and conditions. The review covers the method of preparation, characterization, and biological applications of leucocytic membrane coated NPs. Further, patents related factors, gap of translation from laboratory to clinic, and future prospective were discussed in detail. Overall, the review covers extensive literature to establish leucocytic membrane NPs for targeted drug delivery.

Sitagliptin Induces Tolerogenic Human Dendritic Cells

Sitagliptin, an anti-diabetic drug, is a dipeptidyl peptidase (DPP)-4/CD26 inhibitor with additional anti-inflammatory and immunomodulatory properties. In this study, we investigated for the first time the effect of sitagliptin on the differentiation and functions of human dendritic cells generated from monocytes (MoDCs) for 4 days using the standard GM-CSF/IL-4 procedure. LPS/IFN-γ treatment for an additional 24 h was used for maturation induction of MoDCs. Sitagliptin was added at the highest non-cytotoxic concentration (500 µg/mL) either at the beginning (sita 0d protocol) or after MoDC differentiation (sita 4d protocol). Sitagliptin impaired differentiation and maturation of MoDCs as judged with the lower expression of CD40, CD83, CD86, NLRP3, and HLA-DR, retention of CD14 expression, and inhibited production of IL-β, IL-12p70, IL-23, and IL-27. In contrast, the expression of CD26, tolerogenic DC markers (ILT4 and IDO1), and production of immunoregulatory cytokines (IL-10 and TGF-β) were increased. Generally, the sita 0d protocol was more efficient. Sitagliptin-treated MoDCs were poorer allostimulators of T-cells in MoDC/T-cell co-culture and inhibited Th1 and Th17 but augmented Th2 and Treg responses. Tolerogenic properties of sitagliptin-treated MoDCs were additionally confirmed by an increased frequency of CD4+CD25+CD127- FoxP3+ Tregs and Tr1 cells (CD4+IL-10+FoxP3-) in MoDC/T-cell co-culture. The differentiation of IL-10+ and TGF-β+ Tregs depended on the sitagliptin protocol used. A Western blot analysis showed that sitagliptin inhibited p65 expression of NF-kB and p38MAPK during the maturation of MoDCs. In conclusion, sitagliptin induces differentiation of tolerogenic DCs, and the effect is important when considering sitagliptin for treating autoimmune diseases and allotransplant rejection.

Zwitterionic polymer on silicone implants inhibits the bacteria-driven pathogenic mechanism and progress of breast implant-associated anaplastic large cell lymphoma

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) occurs in the capsule surrounding breast implants. Malignant transformation of T cells by bacteria-driven chronic inflammation may be underlying BIA-ALCL mechanism. Here, we covalently grafted 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymers on a silicone surface and examined its effects against BIA-ALCL pathogenesis. MPC grafting strongly inhibited the adhesion of bacteria and bacteria-causing inflammation. Additionally, cancer T cell proliferation and capsule-derived fibroblast-cancer cell communication were effectively inhibited by MPC grafting. We further demonstrated the effect of MPC against the immune responses causing BIA-ALCL around human silicone implants in micro-pigs. Finally, we generated a xenograft anaplastic T cell lymphoma mouse model around the silicone implants and demonstrated that MPC grafting could effectively inhibit the lymphoma progression. This study is the first to show that bacteria-driven induction and progression of BIA-ALCL can be effectively inhibited by surface modification of implants. STATEMENT OF SIGNIFICANCE: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a major concern in the field of plastic and reconstructive surgery. In this study, we demonstrate strong inhibitory effect of zwitterionic polymer grafting on BIA-ALCL pathogenesis and progression, induced by bacterial infection and inflammation, both in vitro and in vivo. This study provides a molecular basis for the development of novel breast implants that can prevent various potential complications such as excessive capsular contracture, breast implant illness, and BIA-ALCL incidence, as well as for expanding the biomedical applications of zwitterionic polymers.

Eicosapentaenoic acid reduces the proportion of IL-17A-producing T cells in a 3D psoriatic skin model

Psoriasis is a skin disease presenting as erythematous lesions with accentuated proliferation of epidermal keratinocytes, infiltration of leukocytes, and dysregulated lipid metabolism. T cells play essential roles in the disease. n-3 polyunsaturated fatty acids are anti-inflammatory metabolites, which exert an immunosuppressive effect on healthy T cells. However, the precise mechanistic processes of n-3 polyunsaturated fatty acids on T cells in psoriasis are still unrevealed. In this study, we aimed to evaluate the action of eicosapentaenoic acid (EPA) on T cells in a psoriatic skin model produced with T cells. A coculture of psoriatic keratinocytes and polarized T cells was prepared using culture media, which was either supplemented with 10 μM EPA or left unsupplemented. Healthy and psoriatic skin substitutes were produced according to the self-assembly method. In the coculture model, EPA reduced the proportion of IL-17A-positive cells, while increasing that of FOXP3-positive cells, suggesting an increase in the polarization of regulatory T cells. In the 3D psoriatic skin model, EPA normalized the proliferation of psoriatic keratinocytes and diminished the levels of IL-17A. The expression of the proteins of the signal transducer and activator of transcription was influenced following EPA supplementation with downregulation of the phosphorylation levels of signal transducer and activator of transcription 3 in the dermis. Finally, the NFκB signaling pathway was modified in the EPA-supplemented substitutes with an increase in Fas amounts. Ultimately, our results suggest that in this psoriatic model, EPA exerts its anti-inflammatory action by decreasing the proportion of IL-17A-producing T cells.

Deficiency of Pink1 promotes the differentiation of Th1 cells

Previous studies have found that Pink1 is crucial for T cell activation and the function of Treg cells. However, the effect of Pink1 on inflammatory Th1 cells is largely unknown. In the process of Th1 differentiation from human naïve T cells, we found a reduction of Pink1 and Parkin. We then focused our attention on the Pink1 KO mice. Although there was no difference in the baseline of the T cell subset of Pink1 KO mice, Th1 differentiation from Pink1 KO naïve T cells in vitro showed a significant increase. Subsequently, we transferred naïve CD4⁺ T cells into Rag2 KO mice to establish a T-cell colitis mouse model and found that CD4⁺ T cells in mesentery lymph nodes of mice receiving Pink1 KO cells increased significantly, especially Th1 cells. Intestinal IHC staining also showed that the transcription factor T-bet of Th1 increased. Treatment of CD4⁺ T cells from lupus-like mice with mitophagy agonist urolithin A, a reduction of Th1 cells was observed, suggesting the clinical value of using mitophagy agonists to suppress Th1-dominated disease in the future.

Different priming strategies improve distinct therapeutic capabilities of mesenchymal stromal/stem cells: Potential implications for their clinical use

Mesenchymal stromal/stem cells (MSCs) have shown significant therapeutic potential, and have therefore been extensively investigated in preclinical studies of regenerative medicine. However, while MSCs have been shown to be safe as a cellular treatment, they have usually been therapeutically ineffective in human diseases. In fact, in many clinical trials it has been shown that MSCs have moderate or poor efficacy. This inefficacy appears to be ascribable primarily to the heterogeneity of MSCs. Recently, specific priming strategies have been used to improve the therapeutic properties of MSCs. In this review, we explore the literature on the principal priming approaches used to enhance the preclinical inefficacy of MSCs. We found that different priming strategies have been used to direct the therapeutic effects of MSCs toward specific pathological processes. Particularly, while hypoxic priming can be used primarily for the treatment of acute diseases, inflammatory cytokines can be used mainly to prime MSCs in order to treat chronic immune-related disorders. The shift in approach from regeneration to inflammation implies, in MSCs, a shift in the production of functional factors that stimulate regenerative or anti-inflammatory pathways. The opportunity to fine-tune the therapeutic properties of MSCs through different priming strategies could conceivably pave the way for optimizing their therapeutic potential.

Immune modulations of the tumor microenvironment in response to phototherapy

The tumor microenvironment (TME) promotes pro-tumor and anti-inflammatory metabolisms and suppresses the host immune system. It prevents immune cells from fighting against cancer effectively, resulting in limited efficacy of many current cancer treatment modalities. Different therapies aim to overcome the immunosuppressive TME by combining various approaches to synergize their effects for enhanced anti-tumor activity and augmented stimulation of the immune system. Immunotherapy has become a major therapeutic strategy because it unleashes the power of the immune system by activating, enhancing, and directing immune responses to prevent, control, and eliminate cancer. Phototherapy uses light irradiation to induce tumor cell death through photothermal, photochemical, and photo-immunological interactions. Phototherapy induces tumor immunogenic cell death, which is a precursor and enhancer for anti-tumor immunity. However, phototherapy alone has limited effects on long-term and systemic anti-tumor immune responses. Phototherapy can be combined with immunotherapy to improve the tumoricidal effect by killing target tumor cells, enhancing immune cell infiltration in tumors, and rewiring pathways in the TME from anti-inflammatory to pro-inflammatory. Phototherapy-enhanced immunotherapy triggers effective cooperation between innate and adaptive immunities, specifically targeting the tumor cells, whether they are localized or distant. Herein, the successes and limitations of phototherapy combined with other cancer treatment modalities will be discussed. Specifically, we will review the synergistic effects of phototherapy combined with different cancer therapies on tumor elimination and remodeling of the immunosuppressive TME. Overall, phototherapy, in combination with other therapeutic modalities, can establish anti-tumor pro-inflammatory phenotypes in activated tumor-infiltrating T cells and B cells and activate systemic anti-tumor immune responses.

Cytokine Signatures in Psoriatic Arthritis Patients Indicate Different Phenotypic Traits Comparing Responders and Non-Responders of IL-17A and TNFα Inhibitors

This study aimed to explore the dynamic interactions between 32 cytokines and biomarkers in Psoriatic Arthritis (PsA) patients to compare cytokine signatures of treatment responders and non-responders. Biomarkers were measured before and after four months of treatment in 39 PsA patients initiating either Tumor Necrosis Factor alpha inhibitor (TNFi) or Interleukin-17A inhibitor (IL-17Ai). Response to treatment was defined by the composite measure, Disease Activity in Psoriatic Arthritis (DAPSA). A two-component principal component analysis (PCA) was implemented to describe cytokine signatures comparing DAPSA50 responders and non-responders. The cytokine signature of TNFi responders was driven by the correlated cytokines interferon γ (IFNγ) and IL-6, additionally associated with IL-12/IL-23p40, TNFα, and CRP, while the cytokine signature of TNFi non-responders was driven by the correlated cytokines IL-15, IL-8, and IFNγ. IL-17Ai responders were characterized by contributions of strongly correlated Th17 inflammatory cytokines, IL-17A, IL-12/IL-23p40, IL-22 to the cytokine signature, whereas IL-17A and IL-12/IL-23p40 did not demonstrate significant contribution in IL-17Ai non-responders. Based on PCA results it was possible to differentiate DAPSA50 responders and non-responders to treatment, endorsing additional examination of cytokine interaction models in PsA patients and supporting further PsA patient immune stratification to improve individualized treatment of PsA patients.

New insights into the metabolism of Th17 cells

T helper 17 (Th17) cells are IL-17-producing CD4 T cells that play a crucial role in autoimmune diseases. IL-17 is a key cytokine for host protection against mucosal and skin infection but is also one of the major pathogenic cytokines. IL-1 and IL-23 are requisite for stimulating pathogenic Th17 cell differentiation and proliferation. Therapeutics targeting the IL-17/IL-23 pathway are widely used clinically for the treatment of autoimmune diseases. Besides IL-17, pathogenic Th17 cells produce granulocyte-macrophage colony-stimulating factor, tumor necrosis factor α, interferon γ, IL-21 and IL-22. However, Th17-targeted therapy has not yet been established. T cell metabolism orchestrates T cell survival, cell differentiation, epigenetic change and function and each T cell subset favors a particular metabolic pathway. Recent studies have provided novel insights into the role of T cell metabolism in the pathogenesis of autoimmune diseases. The current review focuses on the role of Th17 cell metabolism in autoimmune diseases, particularly glycolysis, amino acid metabolism, lipid metabolism, as well as the regulators of these processes, including mTORC1. Therapeutics targeting T cell metabolism in autoimmune diseases could serve as a possible treatment option for patients who are refractory to or unresponsive to conventional therapy.

Breast Implant-Associated Anaplastic Large Cell Lymphoma

Pathologic staging including assessment of margins is essential for the proper management of patients with breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL). As most patients present with effusion, cytologic examination with immunohistochemistry and/or flow cytometry immunophenotyping are essential for diagnosis. Upon a diagnosis of BIA-ALCL, en bloc resection is recommended. When a tumor mass is not identified, a systematic approach to fixation and sampling of the capsule, followed by pathologic staging and assessment of margins, is essential. Cure is likely when lymphoma is contained within the en bloc resection and margins are negative. Incomplete resection or positive margins require a multidisciplinary team assessment for adjuvant therapy.

Modulation of Skin Inflammatory Responses by Aluminum Adjuvant

Aluminum salt (AS), one of the most commonly used vaccine adjuvants, has immuno-modulatory activity, but how the administration of AS alone may impact the activation of the skin immune system under inflammatory conditions has not been investigated. Here, we studied the therapeutic effect of AS injection on two distinct skin inflammatory mouse models: an imiquimod (IMQ)-induced psoriasis-like model and an MC903 (calcipotriol)-induced atopic dermatitis-like model. We found that injection of a high dose of AS not only suppressed the IMQ-mediated development of T-helper 1 (Th1) and T-helper 17 (Th17) immune responses but also inhibited the IMQ-mediated recruitment and/or activation of neutrophils and macrophages. In contrast, AS injection enhanced MC903-mediated development of the T-helper 2 (Th2) immune response and neutrophil recruitment. Using an in vitro approach, we found that AS treatment inhibited Th1 but promoted Th2 polarization of primary lymphocytes, and inhibited activation of peritoneal macrophages but not bone marrow derived neutrophils. Together, our results suggest that the injection of a high dose of AS may inhibit Th1 and Th17 immune response-driven skin inflammation but promote type 2 immune response-driven skin inflammation. These results may provide a better understanding of how vaccination with an aluminum adjuvant alters the skin immune response to external insults.

Procyanidin B2 3,3″-di-O-gallate suppresses IFN-γ production in murine CD4+ T cells through the regulation of glutamine influx via direct interaction with ASCT2

Excessive activation of CD4⁺ T cells increases cytokine production substantially and induces immune-mediated diseases. Procyanidins are polyphenols with anti-inflammatory properties. Procyanidin B2 (PCB2) gallate [specifically, PCB2 3,3''-di-O-gallate (PCB2DG)] inhibits cytokine production through the suppression of glycolysis via mammalian target of rapamycin (mTOR) in T cells. Several amino acids play critical roles in T cell activation, especially glutamine, which is important in mTOR signaling and interferon-γ (IFN-γ) production in CD4⁺ T cells. However, the mechanisms underlying the effects of PCB2DG, including its interaction partners, have yet to be clarified. In the present study, the mechanisms underlying the inhibitory effect of PCB2DG on IFN-γ through glutamine metabolism regulation were investigated. We found that PCB2DG treatment reduced intracellular glutamine levels in CD4⁺ T cells, whereas the addition of glutamine abrogated the inhibitory effects of PCB2DG on IFN-γ production. The PCB2DG-induced reduction in intracellular glutamine accumulation led to the upregulated expression of activating transcription factor 4, which was induced by the cytoprotective signaling pathway in the amino acid response. In addition, the mRNA and protein expression levels of alanine serine cysteine transporter 2 (ASCT2), a major glutamine transporter in CD4⁺ T cells, were not altered by PCB2DG treatment. Further analysis using a target identification strategy revealed that PCB2DG binds to ASCT2, suggesting that PCB2DG interacts directly with this major glutamine transporter to inhibit glutamine influx. Overall, this study indicates that ASCT2 is a novel target protein of a dietary polyphenol and provides new insights into the mechanism underlying the immunomodulatory effects of polyphenols.

Induction of psoriasis- and atopic dermatitis-like phenotypes in 3D skin equivalents with a fibroblast-derived matrix

Skin homeostasis is a complex regulated process relying on the crosstalk of keratinocytes, fibroblasts and immune cells. Imbalances of T-cell subsets and the cytokine environment can lead to inflammatory skin diseases such as psoriasis (Ps) and atopic dermatitis (AD). Modern tissue engineering provides several in vitro models mimicking Ps and AD phenotypes. However, these models are either limited in their pathological features, life span, sample availability, reproducibility, controlled handling or simplicity. Some models further lack intensive characterization as they solely focus on differentiation and proliferation aspects. This study introduces a self-assembly model in which the pathological T-cell-signalling of Ps and AD was simulated by subcutaneous Th1 and Th2 cytokine stimulation. The self-established dermal fibroblast-derived matrices of these models were hypothesized to be beneficial for proximal cytokine signalling on epidermal keratinocytes. Comprehensive histological and mRNA analyses of the diseased skin models showed a weakened barrier, distinct differentiation defects, reduced cellular adhesion, inflammation and parakeratosis formation. A keratin shift of declining physiological cytokeratin-10 (CK10) towards increasing inflammatory CK16 was observed upon Th1 or Th2 stimulation. Antimicrobial peptides (AMPs) were upregulated in Ps and downregulated in AD models. The AD biomarker genes CA2, NELL2 and CCL26 were further induced in AD. While Ps samples featured basal hyperproliferation, cells in AD models displayed apoptotic signs. In accordance, these well-controllable three-dimensional in vitro models exhibited Ps and AD-like phenotypes with a high potential for disease research and therapeutic drug testing.

Huangshan Floral Mushroom Polysaccharide Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mice by Modulating Th17/Treg Balance in a Gut Microbiota-Dependent Manner

SCOPE

Ulcerative colitis (UC) is a common chronic recurrent inflammatory bowel disease. This study attempts to reveal the improvement mechanism of floral mushroom polysaccharide (FMPS) on UC from the perspective of coordinated interaction between intestinal microbes and intestinal helper T cell 17 (Th17)/regulatory T cell (Treg) balance.

METHODS AND RESULTS

Dextran sulfate sodium (DSS)-induced colitis mice model is used for the experiment. The results suggest that FMPS up-regulated the expression of occludin, ZO-1, and MUC2, and down-regulated the secretion of TNF-α, IL-1β, and IL-6 in colitis mice. Importantly, FMPS restores intestinal Th17/Treg balance. Meanwhile, FMPS can regulate intestinal microorganisms and improve the level of short-chain fatty acids (SCFAs) in colitis mice. Intestinal microbial depletion and fecal microbiota transplantation (FMT) experiments reveal that FMPS ameliorated UC is mediated by intestinal microbiome. Flow cytometry further proves that FMPS restores intestinal Th17/Treg balance in a microbial-dependent manner.

CONCLUSION

These results indicate that FMPS has the potential to improve UC, and its mechanism depends on the restoration of Th17/Treg balance mediated by intestinal microorganisms. Therefore, it is suggested that FMPS dietary supplement can be potentially used to intervene UC.

Transforming growth factor receptor III (Betaglycan) regulates the generation of pathogenic Th17 cells in EAE

The transforming growth factor receptor III (TβRIII) is commonly recognized as a co-receptor that promotes the binding of TGFβ family ligands to type I and type II receptors. Within the immune system, TβRIII regulates T cell development in the thymus and is differentially expressed through activation; however, its function in mature T cells is unclear. To begin addressing this question, we developed a conditional knock-out mouse with restricted TβRIII deletion in mature T cells, necessary because genomic deletion of TβRIII results in perinatal mortality. We determined that TβRIII null mice developed more severe autoimmune central nervous neuroinflammatory disease after immunization with myelin oligodendrocyte peptide (MOG_35-55) than wild-type littermates. The increase in disease severity in TβRIII null mice was associated with expanded numbers of CNS infiltrating IFNγ⁺ CD4⁺ T cells and cells that co-express both IFNγ and IL-17 (IFNγ⁺/IL-17⁺), but not IL-17 alone expressing CD4 T cells compared to Tgfbr3^fl/fl wild-type controls. This led us to speculate that TβRIII may be involved in regulating conversion of encephalitogenic Th17 to Th1. To directly address this, we generated encephalitogenic Th17 and Th1 cells from wild type and TβRIII null mice for passive transfer of EAE into naïve mice. Remarkably, Th17 encephalitogenic T cells from TβRIII null induced EAE of much greater severity and earlier in onset than those from wild-type mice. The severity of EAE induced by encephalitogenic wild-type and Tgfbr3^fl/fl.dLcKCre Th1 cells were similar. Moreover, in vitro restimulation of in vivo primed Tgfbr3^fl/fl.dLcKCre T cells, under Th17 but not Th1 polarizing conditions, resulted in a significant increase of IFNγ⁺ T cells. Altogether, our data indicate that TβRIII is a coreceptor that functions as a key checkpoint in controlling the pathogenicity of autoreactive T cells in neuroinflammation probably through regulating plasticity of Th17 T cells into pathogenic Th1 cells. Importantly, this is the first demonstration that TβRIII has an intrinsic role in T cells.

MicroRNA-183/96/182 cluster in immunity and autoimmunity

MicroRNAs (miRNAs) are crucial post-transcriptional regulators of gene expression in ubiquitous biological processes, including immune-related pathways. This review focuses on the miR-183/96/182 cluster (miR-183C), which contains three miRNAs, miR-183, -96, and -182, having almost identical seed sequences with minor differences. The similarity among seed sequences allows these three miRNAs to act cooperatively. In addition, their minor differences permit them to target distinct genes and regulate unique pathways. The expression of miR-183C was initially identified in sensory organs. Subsequently, abnormal expression of miR-183C miRNAs in various cancers and autoimmune diseases has been reported, implying their potential role in human diseases. The regulatory effects of miR-183C miRNAs on the differentiation and function of both innate and adaptive immune cells have now been documented. In this review, we have discussed the complex role of miR-183C in the immune cells in both normal and autoimmune backgrounds. We highlighted the dysregulation of miR-183C miRNAs in several autoimmune diseases, including systemic lupus erythematosus (SLE), multiple sclerosis (MS), and ocular autoimmune disorders, and discussed the potential for utilizing miR-183C as biomarkers and therapeutic targets of specific autoimmune diseases.

Anti-Psoriatic Effect of Rheum palmatum L. and Its Underlying Molecular Mechanisms

Psoriasis is a chronic, immune-mediated inflammatory skin disorder. Rheum palmatum L. is a common traditional medicinal herb with anti-inflammatory and immunomodulatory activities. This study aimed to investigate the anti-psoriatic effects of the ethanolic extract from R. palmatum L. (RPE) and its chemical constituents, as well as the mechanisms underlying their therapeutic significance. An imiquimod (IMQ)-induced psoriasis-like mouse model was used to examine the anti-psoriatic effect of RPE in vivo. Network pharmacological analysis was performed to investigate the potential targets and related pathways of the RPE components, including rhein, emodin, chrysophanol, aloe-emodin, and physcion. The anti-inflammatory effects and underlying mechanisms of these components were examined using in vitro models. Topical application of RPE alleviated psoriasis-like symptoms and reduced levels of inflammatory cytokines and proliferation markers in the skin. Network pharmacological analysis revealed that RPE components target 20 genes that are linked to psoriasis-related pathways, such as IL-17, MAPK, and TNF signaling pathways. Among the five components of RPE, rhein and emodin showed inhibitory effects on TNF-α and IL-17 production in EL-4 cells, attenuated the production of CXCL8, CXCL10, CCL20, and MMP9, and reduced proliferation in HaCaT cells. Chrysophanol, aloe-emodin, and physcion were less effective than rhein and emodin in suppressing inflammatory responses and keratinocyte proliferation. The effects of these compounds might occur through the inhibition of the ERK, STAT3, and NF-κB signaling pathways. This study suggested the anti-psoriatic effect of RPE, with rhein and emodin as the main contributors that regulate multiple signaling pathways.

Transcriptional inhibition of STAT1 functions in the nucleus alleviates Th1 and Th17 cell-mediated inflammatory diseases

T helper 1 cells (Th1 cells) and T helper 17 cells (Th17 cells) play pivotal roles in the pathogenesis of various autoimmune diseases, including psoriasis and inflammatory bowel disease (IBD). Signal transducer and activator of transcription 1 (STAT1) regulates the Th1 and Th17 cell lineage commitment at an early stage and maintains their immunological functions in vitro and in vivo. The previous strategies to block STAT1 functions to treat autoimmune diseases inhibit Th1 cell activity but simultaneously cause hyper-activation of Th17 cells. Herein, to modulate the functions of pathogenic Th1 and Th17 cells without genetic modification in normal physiological conditions, we generated the nucleus-deliverable form of the transcription modulation domain of STAT1 (ndSTAT1-TMD), which can be transduced into the nucleus of the target cells in a dose- and time-dependent manner without affecting the cell viability and T cell activation signaling events. ndSTAT1-TMD significantly blocked the differentiation of naïve CD4+ T cells into Th1 or Th17 cells via competitive inhibition of endogenous STAT1-mediated transcription, which did not influence Th2 and Treg cell differentiation. When the gene expression profile of Th1 or Th17 cells after ndSTAT1-TMD treatment was analyzed by mRNA sequencing, the expression of the genes involved in the differentiation capacity and the immunological functions of Th1 or Th17 cells were substantially reduced. The therapeutic potential of ndSTAT1-TMD was tested in the animal model of psoriasis and colitis, whose pathogenesis is mainly contributed by Th1 or/and Th17 cells. The symptoms and progression of psoriasis and colitis were significantly alleviated by ndSTAT1-TMD treatment, comparable to anti-IL-17A antibody treatment. In conclusion, our study demonstrates that ndSTAT1-TMD can be a new therapeutic reagent for Th1/17 cell-mediated autoimmune diseases by modulating the functions of pathogenic Th1 and Th17 cells together.

Engineered Lactococcus lactis secreting Flt3L and OX40 ligand for in situ vaccination-based cancer immunotherapy

In situ vaccination is a promising strategy to convert the immunosuppressive tumor microenvironment into an immunostimulatory one with limited systemic exposure and side effect. However, sustained clinical benefits require long-term and multidimensional immune activation including innate and adaptive immunity. Here, we develop a probiotic food-grade Lactococcus lactis-based in situ vaccination (FOLactis) expressing a fusion protein of Fms-like tyrosine kinase 3 ligand and co-stimulator OX40 ligand. Intratumoural delivery of FOLactis contributes to local retention and sustained release of therapeutics to thoroughly modulate key components of the antitumour immune response, such as activation of natural killer cells, cytotoxic T lymphocytes, and conventional-type-1-dendritic cells in the tumors and tumor-draining lymph nodes. In addition, intratumoural administration of FOLactis induces a more robust tumor antigen-specific immune response and superior systemic antitumour efficacy in multiple poorly immune cell-infiltrated and anti-PD1-resistant tumors. Specific depletion of different immune cells reveals that CD8⁺ T and natural killer cells are crucial to the in situ vaccine-elicited tumor regression. Our results confirm that FOLactis displays an enhanced antitumour immunity and successfully converts the 'cold' tumors to 'hot' tumors.

The tumor microenvironment and triple-negative breast cancer aggressiveness: shedding light on mechanisms and targeting

INTRODUCTION

In contrast to other breast cancer subtypes, there are currently limited options of targeted therapies for triple-negative breast cancer (TNBC). Immense research has demonstrated that not only cancer cells but also stromal cells and immune cells in the tumor microenvironment (TME) play significant roles in the progression of TNBC. It is thus critical to understand the components of the TME of TNBC and the interactions between the various cell populations.

AREAS COVERED

The components of the TME of TNBC identified by single-cell technologies are reviewed. Furthermore, the molecular interactions between the cells and the potential therapeutic targets contributing to the progression of TNBC are discussed.

EXPERT OPINION

Single-cell omics studies have contributed to the classification of cells in the TME and the identification of important cell types involved in the progression and the treatment of the tumor. The interactions between cancer cells and stromal cells/immune cells in the TME have led to the discovery of potential therapeutic targets. Experimental data with spatial and temporal resolution will further boost the understanding of the TME of TNBC.

Glyphosate differentially affects the allergic immune response across generations in mice

Exposure to environmental pollutants via food, particularly during the prenatal and early postnatal periods, has been linked to adverse effects on the immune system. Among these pollutants, the widely used pesticide glyphosate has been associated with endocrine disruption, autism, and cancer. Occupational high exposure to glyphosate has also been shown to influence immune function and exacerbate allergic asthma. However, there are no studies investigating the effect of a common low-dose glyphosate exposure on the allergic immune response - neither directly nor across generations. We therefore explored the impact of oral low-dose glyphosate exposure (0.5 and 50 mg/kg body weight/day) on airway inflammation in dams (F0) and the offspring (F1 and F2 generations) using a murine multi-generational asthma model. While exposure to 50 mg/kg glyphosate induced a mild eosinophilic infiltration in the bronchoalveolar lavage and T_H2 cytokine production in the dams, the F1 offspring developed a reduced immune response after maternal exposure to 0.5 mg/kg glyphosate. In particular, decreased lung inflammation, HDM-specific IgE levels, and asthma-relevant cytokine production were primarily observed in the female F1 offspring. However, not only the T_H2 cytokines IL-13 and IL-5 but also the T_H17 cytokine IL-17 and T_H1 cytokine IFN-γ were reduced indicating a more general immunosuppressive function. Notably, the dampened immune response was no longer observed in the female F2 generation. Furthermore, female F1 offspring showed an increased abundance of bacteria in the gut, which have been associated with probiotic-mediated reduced allergic immune responses. Our results suggest a potential immunosuppressive effect of low-dose maternal glyphosate exposure in the F1 offspring that might be mediated by an altered microbiota composition. Further studies are needed to explore if this type of immune response modulation might also be associated with impairments in immune defense upon infectious diseases or even cancer pathology.

Emerging insights of peptide-based nanotherapeutics for effective management of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, prevalent, immune-mediated, inflammatory, joint disorder affecting millions of people worldwide. Despite current treatment options, many patients remain unable to achieve remission and suffer from comorbidities. Because of several comorbidities as well as its chronic nature, it diminishes the quality of patients' life and intensifies socioeconomic cargo. Consolidating peptides with immensely effective drug delivery systems has the ability to alleviate adverse effects associated with conventional treatments. Peptides are widely used as targeting moieties for the delivery of nanotherapeutics. The use of novel peptide-based nanotherapeutics may open up new avenues for improving efficacy by promoting drug accumulation in inflamed joints and reducing off-target cytotoxicity. Peptide therapeutics have grabbed significant attention due to their advantages over small drug molecules as well as complex targeting moieties. In light of this, the market for peptide-based medications is growing exponentially. Peptides can provide the versatility required for the successful delivery of drugs due to their structural diversity and their capability to lead drugs at the site of inflammation while maintaining optimum therapeutic efficacy. This comprehensive review aims to provide an enhanced understanding of recent advancements in the arena of peptide-based nanotherapeutics to strengthen targeted delivery for the effective management of rheumatoid arthritis. Additionally, various peptides having therapeutic roles in rheumatoid arthritis are summarized along with regulatory considerations for peptides.

A Dual Adjuvant System for Intranasal Boosting of Local and Systemic Immunity for Influenza Vaccination

Systemically vaccinated individuals against COVID-19 and influenza may continue to support viral replication and shedding in the upper airways, contributing to the spread of infections. Thus, a vaccine regimen that enhances mucosal immunity in the respiratory mucosa is needed to prevent a pandemic. Intranasal/pulmonary (IN) vaccines can promote mucosal immunity by promoting IgA secretion at the infection site. Here, we demonstrate that an intramuscular (IM) priming-IN boosting regimen with an inactivated influenza A virus adjuvanted with the liposomal dual TLR4/7 adjuvant (Fos47) enhances systemic and local/mucosal immunity. The IN boosting with Fos47 (IN-Fos47) enhanced antigen-specific IgA secretion in the upper and lower respiratory tracts compared to the IM boosting with Fos47 (IM-Fos47). The secreted IgA induced by IN-Fos47 was also cross-reactive to multiple influenza virus strains. Antigen-specific tissue-resident memory T cells in the lung were increased after IN boosting with Fos47, indicating that IN-Fos47 established tissue-resident T cells. Furthermore, IN-Fos47 induced systemic cross-reactive IgG antibody titers comparable to those of IM-Fos47. Neither local nor systemic reactogenicity or adverse effects were observed after IN delivery of Fos47. Collectively, these results indicate that the IM/IN regimen with Fos47 is safe and provides both local and systemic anti-influenza immune responses.

Human arginase 1, a Jack of all trades?

Arginine, a conditionally essential amino acid, plays a crucial role in several metabolic and signalling pathways. Arginine metabolism in the body can be significantly increased under stress or during certain pathological conditions. Depletion of circulating arginine by administering arginine-hydrolysing enzyme has been shown to mitigate varied pathophysiological conditions ranging from cancer, inflammatory conditions, and microbial infection. This review provides an overview of such intriguing expanse of potential applications of recombinant human arginase 1 for different pathological conditions and its status of development.

Polygenic enrichment distinguishes disease associations of individual cells in single-cell RNA-seq data

Single-cell RNA sequencing (scRNA-seq) provides unique insights into the pathology and cellular origin of disease. We introduce single-cell disease relevance score (scDRS), an approach that links scRNA-seq with polygenic disease risk at single-cell resolution, independent of annotated cell types. scDRS identifies cells exhibiting excess expression across disease-associated genes implicated by genome-wide association studies (GWASs). We applied scDRS to 74 diseases/traits and 1.3 million single-cell gene-expression profiles across 31 tissues/organs. Cell-type-level results broadly recapitulated known cell-type-disease associations. Individual-cell-level results identified subpopulations of disease-associated cells not captured by existing cell-type labels, including T cell subpopulations associated with inflammatory bowel disease, partially characterized by their effector-like states; neuron subpopulations associated with schizophrenia, partially characterized by their spatial locations; and hepatocyte subpopulations associated with triglyceride levels, partially characterized by their higher ploidy levels. Genes whose expression was correlated with the scDRS score across cells (reflecting coexpression with GWAS disease-associated genes) were strongly enriched for gold-standard drug target and Mendelian disease genes.

Exosomal B7-H4 from irradiated glioblastoma cells contributes to increase FoxP3 expression of differentiating Th1 cells and promotes tumor growth

Background

Glioblastoma (GBM) is the most common and aggressive form of primary brain tumor. Although numerous postoperative therapeutic strategies have already been developed, including radiotherapy, tumors inevitably recur after several years of treatment. The coinhibitory molecule B7–H4 negatively regulates T cell immune responses and promotes immune escape. Exosomes mediate intercellular communication and initiate immune evasion in the tumor microenvironment (TME).

Objective

This study aimed to determine whether B7–H4 is upregulated by radiation and loaded into exosomes, thus contributing to immunosuppression and enhancing tumor growth.

Methods

Iodixanol density-gradient centrifugation and flow cytometry were used to verify exosomal B7–H4. Naïve T cells were differentiated into Th1 cells, with or without exosomes. T cell-secreted cytokines and markers of T cell subsets were measured. Mechanistically, the roles of B7–H4, and ALIX in GBM were analyzed using databases and tissue samples. Co‐immunoprecipitation, and pull-down assays were used to tested the direct interactions between ATM and ALIX or STAT3. In vitro ATM kinase assays, western blotting, and site-directed mutation were used to assess ATM-mediated STAT3 phosphorylation. Finally, the contribution of exosomal B7–H4 to immunosuppression and tumor growth was investigated in vivo.

Results

Exosomes from irradiated GBM cells decreased the anti-tumor immune response of T cell in vitro and in vivo via delivered B7–H4. Mechanistically, irradiation promoted exosome biogenesis by increasing the ATM-ALIX interaction. Furthermore, the ATM-phosphorylated STAT3 was found to directly binds to the B7–H4 promoter to increase its expression. Finally, the radiation-induced increase in exosomal B7–H4 induced FoxP3 expression during Th1 cell differentiation via the activated STAT1 pathway. In vivo, exosomal B7–H4 decreased the radiation sensitivity of GBM cells, and reduced the survival of GBM mice model.

Conclusion

This study showed that radiation-enhanced exosomal B7–H4 promoted immunosuppression and tumor growth, hence defining a direct link between irradiation and anti-tumor immune responses. Our results suggest that co-administration of radiotherapy with anti-B7-H4 therapy could improve local tumor control and identify exosomal B7–H4 as a potential tumor biomarker.

Current Vaccine Platforms in Enhancing T-Cell Response

The induction of T cell-mediated immunity is crucial in vaccine development. The most effective vaccine is likely to employ both cellular and humoral immune responses. The efficacy of a vaccine depends on T cells activated by antigen-presenting cells. T cells also play a critical role in the duration and cross-reactivity of vaccines. Moreover, pre-existing T-cell immunity is associated with a decreased severity of infectious diseases. Many technical and delivery platforms have been designed to induce T cell-mediated vaccine immunity. The immunogenicity of vaccines is enhanced by controlling the kinetics and targeted delivery. Viral vectors are attractive tools that enable the intracellular expression of foreign antigens and induce robust immunity. However, it is necessary to select an appropriate viral vector considering the existing anti-vector immunity that impairs vaccine efficacy. mRNA vaccines have the advantage of rapid and low-cost manufacturing and have been approved for clinical use as COVID-19 vaccines for the first time. mRNA modification and nanomaterial encapsulation can help address mRNA instability and translation efficacy. This review summarizes the T cell responses of vaccines against various infectious diseases based on vaccine technologies and delivery platforms and discusses the future directions of these cutting-edge platforms.

The role of interleukin-17 in epilepsy

Epilepsy is a common neurological disorder that seriously affects human health. It is a chronic central nervous system dysfunction caused by abnormal discharges of neurons. About 50 million patients worldwide are affected by epilepsy. Although epileptic symptoms of most patients are controllable, some patients with refractory epilepsy have no response to antiseizure medications. It is necessary to investigate the pathogenesis of epilepsy and identify new therapeutic targets for refractory epilepsy. Epileptic disorders often accompany cerebral inflammatory reactions. Recently, the role of inflammation in the onset of epilepsy has increasingly attracted attention. The activation of both innate and adaptive immunity plays a significant role in refractory epilepsy. According to several clinical studies, interleukin-17, an essential inflammatory mediator linking innate and adaptive immunity, increased significantly in the body liquid and epileptic focus of patients with epilepsy. Experimental studies also indicated that interleukin-17 participated in epileptogenesis through various mechanisms. This review summarized the current studies about interleukin-17 in epilepsy and aimed at finding new therapeutic targets for refractory epilepsy.

Umbilical cord mesenchymal stem cell-derived exosomes alleviate collagen-induced arthritis by balancing the population of Th17 and regulatory T cells

Exosomes released by mesenchymal stem cells (MSCs) are thought to function as extensions of the MSCs. However, it remains unclear whether exosomes derived from human umbilical cord MSCs (HUMSCs) possess immunoregulatory functions in rheumatoid arthritis. We report that when mice with collagen-induced arthritis were injected with exosomes derived from HUMSC (HUMSC-Exo) their paws became less swollen, and they had lower serum pro-inflammatory cytokine and anti-collagen IgG levels, and decreased synovial hyperplasia. The HUMSC-Exo appeared to restore the balance between Th17 and Treg cells, and this effect was accompanied by reduced IL-17 and enhanced TGF-β and IL-10 levels. These findings suggest that HUMSC-Exo function as important regulators of the balance between Th1/Th17 and Treg cells during immune and inflammatory responses.

Vitamin A, systemic T-cells, and the eye: Focus on degenerative retinal disease

The first discovered vitamin, vitamin A, exists in a range of forms, primarily retinoids and provitamin carotenoids. The bioactive forms of vitamin A, retinol and retinoic acid, have many critical functions in body systems including the eye and immune system. Vitamin A deficiency is associated with dysfunctional immunity, and presents clinically as a characteristic ocular syndrome, xerophthalmia. The immune functions of vitamin A extend to the gut, where microbiome interactions and nutritional retinoids and carotenoids contribute to the balance of T cell differentiation, thereby determining immune status and contributing to inflammatory disease around the whole body. In the eye, degenerative conditions affecting the retina and uvea are influenced by vitamin A. Stargardt’s disease (STGD1; MIM 248200) is characterised by bisretinoid deposits such as lipofuscin, produced by retinal photoreceptors as they use and recycle a vitamin A-derived chromophore. Age-related macular degeneration features comparable retinal deposits, such as drusen featuring lipofuscin accumulation; and is characterised by parainflammatory processes. We hypothesise that local parainflammatory processes secondary to lipofuscin deposition in the retina are mediated by T cells interacting with dietary vitamin A derivatives and the gut microbiome, and outline the current evidence for this. No cures exist for Stargardt’s or age-related macular degeneration, but many vitamin A-based therapeutic approaches have been or are being trialled. The relationship between vitamin A’s functions in systemic immunology and the eye could be further exploited, and further research may seek to leverage the interactions of the gut-eye immunological axis.

IL-6-Driven pSTAT1 Response Is Linked to T Cell Features Implicated in Early Immune Dysregulation

Elevated levels and enhanced sensing of the pro-inflammatory cytokine interleukin-6 (IL-6) are key features of many autoimmune and inflammatory diseases. To better understand how IL-6 signaling may influence human T cell fate, we investigated the relationships between levels of components of the IL-6R complex, pSTAT responses, and transcriptomic and translational changes in CD4+ and CD8+ T cell subsets from healthy individuals after exposure to IL-6. Our findings highlight the striking heterogeneity in mbIL-6R and gp130 expression and IL-6-driven pSTAT1/3 responses across T cell subsets. Increased mbIL-6R expression correlated with enhanced signaling via pSTAT1 with less impact on pSTAT3, most strikingly in CD4+ naïve T cells. Additionally, IL-6 rapidly induced expression of transcription factors and surface receptors expressed by T follicular helper cells and altered expression of markers of apoptosis. Importantly, many of the features associated with the level of mbIL-6R expression on T cells were recapitulated both in the setting of tocilizumab therapy and when comparing donor CD4+ T cells harboring the genetic variant, IL6R Asp358Ala (rs2228145), known to alter mbIL-6R expression on T cells. Collectively, these findings should be taken into account as we consider the role of IL-6 in disease pathogenesis and translating IL-6 biology into effective therapies for T cell-mediated autoimmune disease.

Fatty Acid Metabolism and T Cells in Multiple Sclerosis

Cellular metabolic remodeling is intrinsically linked to the development, activation, differentiation, function, and survival of T cells. T cells transition from a catabolic, naïve state to an anabolic effector state upon T cell activation. Subsequently, specialization of T cells into T helper (Th) subsets, including regulatory T cells (Treg), requires fine-tuning of metabolic programs that better support and optimize T cell functions for that particular environment. Increasingly, studies have shown that changes in nutrient availability at both the cellular and organismal level during disease states can alter T cell function, highlighting the importance of better characterizing metabolic-immune axes in both physiological and disease settings. In support of these data, a growing body of evidence is emerging that shows specific lipid species are capable of altering the inflammatory functional phenotypes of T cells. In this review we summarize the metabolic programs shown to support naïve and effector T cells, and those driving Th subsets. We then discuss changes to lipid profiles in patients with multiple sclerosis, and focus on how the presence of specific lipid species can alter cellular metabolism and function of T cells.

The Temporal and Spatial Changes of Th17, Tregs, and Related Cytokines in Epilepsy Lesions

The cellular and molecular mechanisms in pathogenesis and development of epilepsy are still unclear. Specific inflammatory mediators and immune cells may play an important role. The aim of the present study was to investigate the temporal and spatial changes of Th17, Tregs, and related cytokines in epilepsy lesions. LiCl-pilocarpine-induced temporal lobe epilepsy (TLE) rat models were established, sensorimotor function was examined using modified neurological severity score (mNSS), cognitive function was evaluated by Morris water maze (MWM) test, pathological damages were detected by H&E staining and Nissl staining, helper T cells 17 (Th17), regulatory CD4+ T cells (Tregs), and their related cytokines were detected by Western blotting and immune staining. Results showed that Th17 and its related cytokines in epilepsy lesions played a role mainly at acute phase of epilepsy, and they were positively correlated with the pathological changes in the hippocampus and neurological and cognitive dysfunction caused by epilepsy. Conversely, Tregs and their related cytokines mainly played a role at progressive phase and had the opposite effect. Th17 and Tregs restricted each other during the recovery phase to achieve functional balance. Our results suggested that Th17, Tregs, and related cytokines in epilepsy lesions played an important role in the pathogenesis and development of epilepsy and balancing Th17 and Tregs may be efficacious therapeutics for patients with epilepsy.

Immuno-Engineered Nanodecoys for the Multi-Target Anti-Inflammatory Treatment of Autoimmune Diseases

Overactivated T cells and overproduced pro-inflammatory cytokines form a self-amplified signaling loop to continuously exacerbate the dysregulated inflammatory response and propel the progression of autoimmune diseases (AIDs). Herein, immuno-engineered nanodecoys (NDs) based on poly(lactic-co-glycolic acid) nanoparticles coated with programmed death-ligand 1 (PD-L1)-expressing macrophage membrane (PRM) are developed to mediate multi-target interruption of the self-promoted inflammatory cascade in AIDs. The PRM collected from IFN-γ-treated RAW 264.7 cells possesses elevated surface levels of adhesion molecule receptors and pro-inflammatory cytokine receptors, and, thus, systemically administered PRM NDs afford higher accumulation level in inflamed tissues and stronger scavenging efficiency toward multiple pro-inflammatory cytokines. More importantly, IFN-γ treatment induces remarkable PD-L1 expression on PRM, thereby allowing PRM NDs to bind membrane-bound programmed death-1 (PD-1) on CD4⁺ T cell surfaces or neutralize free soluble PD-1, which reconstructs the PD-1/PD-L1 inhibitory axis to suppress CD4⁺ T cell activation and restore immune tolerance. As such, PRM NDs provoke potent and cooperative anti-inflammatory and immune-suppressive efficacies to alleviate autoimmune damages in Zymosan A-induced arthritis mice and dextran sulfate sodium-induced ulcerative colitis mice. This study provides an enlightened example for the immuno-engineering of cell-membrane-based NDs, rendering promising implications into the treatment of AIDs via multi-target immune-modulation.

Shigella flexneri vaccine development: Oral administration of peptides derived from the 49.8 kDa pili protein subunit activates the intestinal immune response in mice

Background and Aim:

The morbidity and mortality of Shigella infections remain a global challenge. Epitope-based vaccine development is an emerging strategy to prevent bacterial invasion. This study aimed to identify the ability of the 49.8 kDa pili subunit adhesin protein epitope of Shigella flexneri to induce an intestinal immune response in mice.

Materials and Methods:

Thirty adult male Balb/c mice were divided into a control group, cholera toxin B subunit (CTB) group, CTB+QSSTGTNSQSDLDS (pep_1) group, CTB+DTTITKAETKTVTKNQVVDTPVTTDAAK (pep_2) group, and CTB+ ATLGATLNRLDFNVNNK (pep_3). We performed immunization by orally administering 50 μg of antigen and 50 μl of adjuvant once a week over 4 weeks. We assessed the cellular immune response by quantifying T helper 2 (Th2) and Th17 using flow cytometry. In addition, we assessed the humoral immune response by quantifying interleukin (IL-4), IL-17, secretory immunoglobulin A (sIgA), and β-defensin using enzyme-linked immunoassay. Statistical analysis was performed using one-way analysis of variance and Kruskal–Wallis test.

Results:

Peptide oral immunization increases the cellular immune response as reflected by the increase of Th2 (p=0.019) and Th17 (p=0.004) cell counts, particularly in the CTB_pep_1 group. Humoral immune response activation was demonstrated by increased IL-4 levels, especially in the CTB+pep_3 group (p=0.000). The IL-17 level was increased significantly in the CTB+pep_1 group (p=0.042). The mucosal immune response was demonstrated by the sIgA levels increase in the CTB+pep_3 group (p=0.042) and the β-defensin protein levels (p=0.000).

Conclusion:

All selected peptides activated the cellular and humoral immune responses in the intestine of mice. Further studies are necessary to optimize antigen delivery and evaluate whether the neutralizing properties of these peptides allow them to prevent bacterial infection.

Coesisting inflammatory skin diseases: Tildrakizumab to control psoriasis and Omalizumab for urticaria

In Western countries the number of individuals suffering from an autoimmune condition is constantly growing and often patients suffering from autoimmune disease are susceptible to developing a second autoimmune disorder. We report a case of an adult female patient affected by psoriasis vulgaris and treated with tildrakizumab, a humanized monoclonal antibody targeting interleukin-23, who later developed chronic spontaneous urticaria and started omalizumab, a humanized antibody to IgE, showing a favorable outcome. We speculate that the two combined therapies have restored the cytokine balance bringing it towards tolerance and remission of the two pathologies. It is conceivable that tildrakizumab may have a synergic action with omalizumab in the treatment of urticaria in patients affected by both psoriasis and urticaria. Our case and the study of the mechanisms of action of the two drugs suggest how the two therapies can act with an interlocking mechanism in achieving the final therapeutic effect.

Forsythoside A Alleviates Imiquimod-Induced Psoriasis-like Dermatitis in Mice by Regulating Th17 Cells and IL-17A Expression

Psoriasis is a recurrent inflammatory skin disease characterized by redness and scaly skin lesions with itchy or painful sensations. Forsythoside A, one of the main active compounds isolated from the fruit of Forsythia suspensa, has been widely applied to treat inflammatory diseases in the clinical use of traditional oriental medicine. However, the effect of forsythoside A on psoriasis remains unclear. This study aimed to explore the therapeutic effects and immune regulation of forsythoside A on psoriasis. C57BL/6 mice were divided into six groups and treated with imiquimod cream on their shaved back skin to induce psoriasis-like dermatitis. Different doses of forsythoside A (5 mg/kg, 10 mg/kg, or 20 mg/kg) were administered to the respective treatment groups. Skin redness, scaling, and ear thickness were measured; keratinocyte proliferation and inflammatory cytokine expression were detected by hematoxylin–eosin and immunohistochemical staining. Th17 cells in the inguinal lymph nodes were detected by flow cytometric analysis. IL-17A levels were measured using ELISA. The results showed that forsythoside A relieved psoriatic skin symptoms such as skin redness, thickness, scaling, and reduced epidermal thickening. The expression of IL-6, IL-17, and Ki-67 was downregulated in the forsythoside-A-treated groups. Th17 cell expression in inguinal lymph nodes and IL-17A secretion was suppressed by forsythoside A. In conclusion, forsythoside A was found to alleviate imiquimod-induced psoriasis-like dermatitis in mice by suppressing Th17 development and IL-17A secretion. These findings demonstrate the feasibility of forsythoside A in treating human psoriasis.

Th1-Like Treg Cells Are Increased But Deficient in Function in Rheumatoid Arthritis

OBJECTIVES

This study aimed to investigate the changes in quantity and function of T helper (Th)-like T regulatory (Treg) cell subsets in peripheral blood (PB) and synovial fluid (SF) of rheumatoid arthritis (RA) patients and to understand their relationship with disease activity.

METHODS

A total of 86 RA patients and 76 gender and age-matched healthy controls (HC) were enrolled in this study. Th-like Treg frequency and function were determined using flow cytometry. The inhibitory function of Th-like Treg cells was detected using an in vitro co-culture suppression assay.

RESULTS

The proportion and absolute number of Th1-like Treg cells from RA PB and RA SF were significantly higher than those of HC PB. In RA SF, the proportions of Treg cells and Th1-like Treg cells were significantly lower in the elevated erythrocyte sedimentation rate or the C-Reactive Protein group, and in the positive groups of anti-CCP antibody and anti-MCV antibody. Additionally, the proportions of Treg cells and Th1-like Treg cells from RA SF were negatively correlated with disease activity. However, the expression levels of CD73 and TGF-β1 in Th1-like Treg cells were decreased, and these Treg cells could not effectively inhibit the proliferation of effector T (Teff) cells.

CONCLUSION

Our data indicate that Th1-like Treg cells are the predominant Treg cell subset in RA SF, but their suppressive function is defective. Improving the function of Th1-like Treg cells may control inflammation in joints and provide new strategies for Treg-targeted therapies in RA.