Adoptive transfer of Tregs: A novel strategy for cell-based immunotherapy in spontaneous abortion: Lessons from experimental models

The humoral immune landscape in Parkinson's disease: Unraveling antibody and B cell changes

Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by the accumulation of α-synuclein (α-syn) in the brain and progressive loss of dopaminergic neurons in the substantia nigra (SN) region of the brain. Although the role of neuroinflammation and cellular immunity in PD has been extensively studied, the involvement of humoral immunity mediated by antibodies and B cells has received less attention. This article provides a comprehensive review of the current understanding of humoral immunity in PD. Here, we discuss alterations in B cells in PD, including changes in their number and phenotype. Evidence mostly indicates a decrease in the quantity of B cells in PD, accompanied by a shift in the population from naïve to memory cells. Furthermore, the existence of autoantibodies that target several antigens in PD has been investigated (i.e., anti-α-syn autoantibodies, anti-glial-derived antigen antibodies, anti-Tau antibodies, antineuromelanin antibodies, and antibodies against the renin-angiotensin system). Several autoantibodies are generated in PD, which may either provide protection or have harmful effects on disease progression. Furthermore, we have reviewed studies focusing on the utilization of antibodies as a potential treatment for PD, both in animal and clinical trials. This review sheds light on the intricate interplay between antibodies and the pathological processes in PD, including complement system activation.

Shoutai Wan treatment upregulates the expression of TNFAIP3 and improves T cell immune tolerance at maternal-fetal interface

Shoutai Wan (STW) is a traditional Chinese medicine formula used to treat various conditions. The objective of this study was to evaluate the impact of STW on the abortion rate in the URSA mouse model and elucidate its underlying molecular mechanisms. Female CBA/J mice were mated with male DBA/2 mice to establish the URSA model. Network pharmacological analysis was employed to investigate the potential molecular mechanisms of STW. Hematoxylin-eosin staining, immunofluorescence, and ELISA were performed to examine placental microenvironmental changes, protein expression related to TNFAIP3 and the NF-κB signaling pathway. Treatment with STW reduced the abortion rate in URSA model mice and improved trophoblast development. TNFAIP3 was identified as a potential target of STW for treating URSA, as STW enhanced TNFAIP3 protein expression while decreasing IL-6 and TNF-α secretion in the placenta. Moreover, STW upregulated TNFAIP3 protein expression and Foxp3 mRNA levels, increased the production of anti-inflammatory cytokines such as IL-10 and TGF-β1, and decreased p-NF-κB expression in CD4+ cells at the placenta. The findings of this study indicate that STW treatment reduces the abortion rate in the URSA mouse model. These effects are likely mediated by increased TNFAIP3 expression and decreased NF-κB signaling pathway activity at the maternal-fetal interface. These molecular changes may contribute to the regulation of T cell immunity and immune tolerance during pregnancy.

Beyond Immune Balance: The Pivotal Role of Decidual Regulatory T Cells in Unexplained Recurrent Spontaneous Abortion

Recurrent spontaneous abortion (RSA) is defined as two or more consecutive pregnancy failures, which brings tremendous stress to women of childbearing age and seriously affects family well-being. However, the reason in about 50% of cases remains unknown and is defined as unexplained recurrent spontaneous abortion (URSA). The immunological perspective in URSA has attracted widespread attention in recent years. The embryo is regarded as a semi-allogeneic graft to the mother. A successful pregnancy requires transition to an immune environment conducive to embryo survival at the maternal-fetal interface. As an important member of regulatory immunity, regulatory T (Treg) cells play a key role in regulating immune tolerance at the maternal-fetal interface. This review will focus on the phenotypic plasticity and lineage stability of Treg cells to illustrate its relationship with URSA.

A lncRNA Dleu2-encoded peptide relieves autoimmunity by facilitating Smad3-mediated Treg induction

Micropeptides encoded by short open reading frames (sORFs) within long noncoding RNAs (lncRNAs) are beginning to be discovered and characterized as regulators of biological and pathological processes. Here, we find that lncRNA Dleu2 encodes a 17-amino-acid micropeptide, which we name Dleu2-17aa, that is abundantly expressed in T cells. Dleu2-17aa promotes inducible regulatory T (iTreg) cell generation by interacting with SMAD Family Member 3 (Smad3) and enhancing its binding to the Foxp3 conserved non-coding DNA sequence 1 (CNS1) region. Importantly, the genetic deletion of Dleu2-17aa in mice by start codon mutation impairs iTreg generation and worsens experimental autoimmune encephalomyelitis (EAE). Conversely, the exogenous supplementation of Dleu2-17aa relieves EAE. Our findings demonstrate an indispensable role of Dleu2-17aa in maintaining immune homeostasis and suggest therapeutic applications for this peptide in treating autoimmune diseases.

Memory regulatory T cells in pregnancy

Pregnancy requires the process of maternal immune tolerance to semi-allogeneic embryos. In contrast, an overreactive maternal immune system to embryo-specific antigens is likely to result in the rejection of embryos while damaging the invading placenta, such that the likelihood of adverse pregnancy outcomes can be increased. Regulatory T cells (Tregs) are capable of suppressing excessive immune responses and regulating immune homeostasis. When stimulating Tregs, specific antigens will differentiate into memory Tregs with long-term survival and rapid and powerful immune regulatory ability. Immunomodulatory effects mediated by memory Tregs at the maternal-fetal interface take on critical significance in a successful pregnancy. The impaired function of memory Tregs shows a correlation with various pregnancy complications (e.g., preeclampsia, gestational diabetes mellitus, and recurrent pregnancy losses). However, the differentiation process and characteristics of memory Tregs, especially their role in pregnancy, remain unclear. In this study, a review is presented in terms of memory Tregs differentiation and activation, the characteristics of memory Tregs and their role in pregnancy, and the correlation between memory Tregs and pregnancy complications. Furthermore, several potential therapeutic methods are investigated to restore the function of memory Tregs in accordance with immunopathologies arising from memory Tregs abnormalities and provide novel targets for diagnosing and treating pregnancy-associated diseases.

Genetically Engineered Exosomes as a Potential Regulator of Th1 Cells Response in Rheumatoid Arthritis

Background: Rheumatoid arthritis is a long-lasting inflammatory disease that usually involves joints, but it can also affect other organs, including the skin and lungs. In this case, it is important to maintain a balance between beneficial pro-inflammatory activity and harmful overactivation of the T helper cells (Th). We strive to investigate in this study the possibilities for the effect of mesenchymal stem cells (MSCs)-derived exosomes containing miR-146a/miR-155 on the lymphocyte population and function. Methods: Exosomes were isolated from overexpressed miR-146a/miR-155 MSCs for the purpose of this analysis. Splenocytes were isolated from collagen-induced arthritis (CIA) and control mice. It was important to consider the expressions of certain predominant autoimmune-response genes, including T-bet and interferon-γ (IFNγ), by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. It turned out to be a significant consideration with p < 0.05. Results: The results are expressed in percentages with respect to miR-146a/AntimiR-155 transduced MSC-derived exosomes treatment, which significantly decreased the mRNA expression level of IFNγ in healthy mice (p < 0.05). miR-146a transduced MSC-derived exosomes treatment significantly reduced the mRNA expression level of IFNγ in CIA mice (p < 0.05). It should be noted that the secretion of the pro-inflammatory factor IFNγ in CIA mice was inhibited in almost all groups (p < 0.05). Conclusion: Many research groups have mainly focused on strategies for reducing pro-inflammatory cytokines. This approach was recently suggested and investigated in our research team and suggested that manipulation of MSCs-derived exosomes could minimize pro-inflammatory cytokine production to strike a balance among Th subsets. These approaches tend to appear to achieve better results in the regulation of the immune system by the use of engineered exosomes derived from MSCs. By providing accurate information the reasonably practicable use of exosomes for cell-free therapy can be established.

The effectiveness and safety of intrauterine infusion of autologous regulatory T cells (Tregs) in patients with recurrent pregnancy loss and low levels of endometrial FoxP3+ cells: A retrospective cohort study

PROBLEM

Regulatory T cells (Tregs) are a specialized type of T cells that help maintain immune tolerance and homeostasis. The potential of Tregs cell-based therapies in treating diseases has been demonstrated in several clinical trials, which have shown promising outcomes and high safety in autoimmune diseases, transplant rejection, and graft-versus-host disease. However, their effectiveness and safety in improving endometrial receptivity and reducing pregnancy loss in human reproduction are unknown.

METHOD OF STUDY

The study used a retrospective design and included patients with recurrent pregnancy loss (RPL) and lower levels of endometrial FoxP3⁺ Tregs. Patients in the Tregs group (n = 33) received intrauterine Tregs infusion three times during the follicular phase, while the control group (n = 28) did not receive any intrauterine infusion.

RESULTS

The intrauterine infusion of autologous Tregs increased the levels of FoxP3⁺ Tregs and CD56⁺ NK cells. Patients in the Treg group had higher live birth rates and lower miscarriage rates, especially early miscarriage rates. However, the two groups had no differences in the implantation rate, clinical pregnancy rate, and percentage of preterm delivery.

CONCLUSIONS

The findings suggest that intrauterine Tregs infusion may be a potential therapeutic approach for RPL. Further research in larger clinical trials is needed to confirm these findings.

Pparα knockout in mice increases the Th17 development by facilitating the IKKα/RORγt and IKKα/Foxp3 complexes

The helper CD4+ T cell-type 17 (Th17) cells and regulatory CD4+ T cells (Tregs) are balanced through numerous molecular regulators, particularly metabolic factors, and their alteration causes immune dysregulation. Herein, we report that peroxisome proliferator of activated receptor-alpha (Pparα), a lipid metabolism regulator, suppresses Th17 differentiation. We demonstrated that Pparα ablation improves Th17 and pro-Th17 factor HIF-1α by enhancing the expression and nuclear localization of NFκB-activator IκB kinase-alpha (IKKα). Unexpectedly, we found that IKKα directly interacts with RORγt and enhances the expression of Il17a gene. Meanwhile, IKKα also interacts with Foxp3, leading to the post-translational regulation of Foxp3 by elevating its proteasomal degradation, and influencing Th17 development. Pparα deficiency leads to enhanced Th17 development in vivo and is associated with enhanced pathology in a murine experimental autoimmune encephalomyelitis (EAE) model. Overall, our data indicate that Pparα may serve as a potential therapeutic target for autoimmune and inflammatory diseases.

Immunomodulatory Therapeutic Effects of Curcumin on M1/M2 Macrophage Polarization in Inflammatory Diseases

BACKGROUND

Due to their plasticity, macrophages exert critical effects on both promoting and suppressing inflammatory processes. Pathologic inflammatory conditions are frequently correlated with dynamic alterations in macrophage activation, with classically activated M1 cells associated with the promotion and maintenance of inflammation and M2 cells being linked to the resolution or smouldering of chronic inflammation. Inflammation deputes a common feature of various chronic diseases and the direct involvement in the insurgence and development of these conditions. Macrophages participate in an autoregulatory loop characterizing the inflammatory process, as they produce a wide range of biologically active mediators that exert either deleterious or beneficial effects during the inflammation. Therefore, balancing the favorable ratios of M1/M2 macrophages can help ameliorate the inflammatory landscape of pathologic conditions. Curcumin is a component of turmeric with many pharmacological properties.

OBJECTIVE

Recent results from both in-vivo and in-vitro studies have indicated that curcumin can affect polarization and/or functions of macrophage subsets in the context of inflammation-related diseases. There is no comprehensive review of the impact of curcumin on cytokines involved in macrophage polarization in the context of inflammatory diseases. The present review will cover some efforts to explore the underlying molecular mechanisms by which curcumin modulates the macrophage polarization in distant pathological inflammatory conditions, such as cancer, autoimmunity, renal inflammation, stroke, atherosclerosis, and macrophage-driven pathogenesis.

RESULTS

The accumulation of the findings from in vitro and in vivo experimental studies suggests that curcumin beneficially influences M1 and M2 macrophages in a variety of inflammatory diseases with unfavorable macrophage activation.

CONCLUSION

Curcumin not only enhances anti-tumor immunity (via shifting M polarization towards M1 phenotype and/or up-regulation of M1 markers expression) but ameliorates inflammatory diseases, including autoimmune diseases (experimental autoimmune myocarditis and Behcet's disease), nephropathy, chronic serum sickness, stroke, and atherosclerosis.

Circ-CCNB1 Modulates Trophoblast Proliferation and Invasion in Spontaneous Abortion by Regulating miR-223/SIAH1 axis

CONTEXT

Spontaneous abortion (SA) is a common disorder in early pregnancy. Circular RNAs (circRNAs) have been reported to exert important regulatory effects on trophoblast function and embryo development.

OBJECTIVE

The aim of this study was to explore whether and how circRNAs regulate trophoblast function in SA during early pregnancy.

METHODS

Cell proliferation, 5-bromo-2-deoxyuridine (BrdU) staining, Transwell, immunofluorescence, Western blot, RNA pull-down, and dual luciferase reporter assays were performed to investigate the effect of circRNA cyclin B1 (circ-CCNB1) on trophoblast function in HTR-8/SVneo and JEG-3 cells.

RESULTS

An in vitro study demonstrated that upregulation of circ-CCNB1 significantly inhibited trophoblast proliferation and invasion compared with the controls using HTR-8/SVneo and JEG-3 cells, respectively. Moreover, miR-223 was downregulated in the villous tissues of patients with SA and was further predicted and shown to negatively interact with circ-CCNB1, which is involved in trophoblast proliferation and invasion. Using bioinformatics tools and subsequent RNA pull-down and dual luciferase assays, we found that miR-223 directly targets seven in absentia homolog-1 (SIAH1) and that upregulation of miR-223 decreased circ-CCNB1-induced SIAH1 expression levels in HTR-8/SVneo cells. Interestingly, upregulation of circ-CCNB1 suppressed trophoblast proliferation and invasion through inhibition of CCNB1 nuclear translocation induced by SIAH1. Downregulation of SIAH1 enhanced circ-CCNB1-suppressed CCNB1 nuclear protein expression in trophoblast cells.

CONCLUSION

Circ-CCNB1 served as a modulator of trophoblast proliferation and invasion by sponging miR-223, thus forming a regulatory network of circ-CCNB1/miR-223/SIAH1 in modulating CCNB1 nuclear translocation, which enabled us to elucidate the molecular mechanisms involved in normal embryo implantation or in SA.

miR-146a-5p enhances embryo survival in unexplained recurrent spontaneous abortion by promoting M2 polarization of decidual macrophages

Unexplained recurrent spontaneous abortion (URSA) is one of the most challenging conditions in the reproductive field, and macrophage M1/M2 polarization disorder is involved in URSA pathogenesis, although the relevant mechanisms are undefined. miR-146a-5p possesses an immunoregulatory role and is expressed in decidual immune cells, and this study aims to investigate its effect on decidual macrophage polarization and therapeutic prospects in URSA, which has never been reported. The levels of M1/M2 markers in the deciduae and the miR-146a-5p expression in the decidual macrophages of URSA and healthy pregnant women were first detected and analyzed. Then, the in vitro effect of miR-146a-5p on the M1/M2 polarization and the secretion of inflammatory cytokines was investigated in Tamm-Horsfall protein-1 (THP-1)-induced macrophages. Finally, the in vivo immunotherapeutic effect of miR-146a-5p on embryo survival and the potential mechanisms were evaluated in a murine model of immune-based URSA. As a result, the abnormal M1/M2 polarization, which showed a shift towards the M1 phenotype and correlated with the decreased expression of miR-146a-5p, was verified in human URSA decidual macrophages. miR-146a-5p could inhibit M1 polarization, promote M2 polarization, and result in an anti-inflammatory microenvironment in THP-1-induced macrophages. The intravenous injection of exogenous miR-146a-5p in the first trimester of pregnant URSA mice significantly reduced the embryo resorption rate and promoted the M2 polarization of decidual macrophages. In conclusion, miR-146a-5p enhances embryo survival in URSA by promoting decidual macrophage polarization toward an M2 phenotype, giving new ideas and potential targets for subsequent research on the pathogenesis and immunotherapeutic strategies of URSA.

The Regulatory-T-Cell Memory Phenotype: What We Know

In immunology, the discovery of regulatory T (Treg) cells was a major breakthrough. Treg cells play a key role in pregnancy maintenance, in the prevention of autoimmune responses, and in the control of all immune responses, including responses to self cells, cancer, infection, and a transplant. It is currently unclear whether Treg cells are capable of long-term memory of an encounter with an antigen. Although the term “immunological memory” usually means an enhanced ability to protect the body from reinfection, the memory of the suppressive activity of Treg cells helps to avoid the state of generalized immunosuppression that may result from the second activation of the immune system. In this review, we would like to discuss the concept of regulatory memory and in which tissues memory Treg cells can perform their functions.

The therapeutic potential of regulatory T cells in reducing cardiovascular complications in patients with severe COVID-19

The SARS coronavirus 2 (SARS CoV-2) causes Coronavirus Disease (COVID-19), is an emerging viral infection. SARS CoV-2 infects target cells by attaching to Angiotensin-Converting Enzyme (ACE2). SARS CoV-2 could cause cardiac damage in patients with severe COVID-19, as ACE2 is expressed in cardiac cells, including cardiomyocytes, pericytes, and fibroblasts, and coronavirus could directly infect these cells. Cardiovascular disorders are the most frequent comorbidity found in COVID-19 patients. Immune cells such as monocytes, macrophages, and T cells may produce inflammatory cytokines and chemokines that contribute to COVID-19 pathogenesis if their functions are uncontrolled. This causes a cytokine storm in COVID-19 patients, which has been associated with cardiac damage. Tregs are a subset of immune cells that regulate immune and inflammatory responses. Tregs suppress inflammation and improve cardiovascular function through a variety of mechanisms. This is an exciting research area to explore the cellular, molecular, and immunological mechanisms related to reducing risks of cardiovascular complications in severe COVID-19. This review evaluated whether Tregs can affect COVID-19-related cardiovascular complications, as well as the mechanisms through which Tregs act.

Immunopharmacological properties of VitD3: 1,25VitD3 modulates regulatory T cells and Th17 cells and the cytokine balance in PBMCs from women with unexplained recurrent spontaneous abortion [URSA]

BACKGROUND

VitD3 may contribute to a successful pregnancy through modulation of immune responses, so VitD3 deficiency may have a role in the immunopathogenesis of unexplained recurrent spontaneous abortion [URSA]. However, the mechanisms of immunomodulatory actions of VitD3 in decreasing the risk of recurrent spontaneous abortion have not been understood well.

OBJECTIVE

The purpose of this research was to investigate the influence of 1,25VitD3 on regulatory T cells /Th17 axis, the gene expressions and concentrations of related cytokines including, TGF-β, IL-10, IL-6, IL-23, and IL-17A in peripheral blood mononuclear cells [PBMCs] of healthy women as a control group and women with URSA.

METHOD

Isolation of PBMCs was performed from peripheral blood of the subjects of the studied groups [20 women with URSA as a case group, and 20 control women]. The effects of 1,25VitD3 [50 nM, for 24 hours] on the studied parameters were evaluated and were compared to the positive and negative controls in vitro. Flow cytometry analysis was used to determine the percentages of regulatory T cells and Th17 cells. For gene expression measurement and cytokines assay, Real-time PCR and ELISA were carried out.

RESULTS

The proportion of regulatory T cells was markedly lower, while the proportion of Th17 cells in women with URSA was considerably higher than in the control group [P=0.01, P=0.01]. The ratio of the frequency of Tregs to the baseline [1,25VitD3/Untreated] increased, while the ratio of the frequency of Th17 cells to the baseline decreased in women with URSA relative to the controls [P= 0.01, P=0.04]. 1,25VitD3 increased IL-10 expressions at both the protein and mRNA levels in PBMCs in women with URSA relative to the control group [P=0.0001, P=0.04]. TGF-β levels in the cultured supernatants decreased significantly in the case group in the presence of 1,25VitD3 relative to the controls [P=0.03]. 1,25VitD3 treatment also significantly decreased gene expressions of IL-6, IL-17A, and IL-23 in PBMCs of women with URSA [P=0.01, P=0.001, P=0.0005], as well as the levels of those cytokines in cell culture supernatants [P=0.03, P=0.02, P=0.01, respectively] in women with URSA relative to the controls.

CONCLUSION

According to the findings of this research, modulation of immune responses by 1,25VitD3 is accomplished by strengthening Tregs function and inhibiting inflammatory responses of Th17 cells which may have a positive impact on pregnancy outcome. Thus, as an immunomodulating agent, VitD3 may be effective in reducing the risk of URSA.