scholarly journals Effects of Pegylated Interferon Alpha and Ribavirin (pegIFN-α/RBV) Therapeutic Approach on Regulatory T Cells in HCV-Monoinfected and HCV/HIV-Coinfected Patients

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1448
Author(s):  
Kamil Grubczak ◽  
Anna Grzeszczuk ◽  
Monika Groth ◽  
Anna Hryniewicz ◽  
Anna Kretowska-Grunwald ◽  
...  

Approximately 25% of HIV-infected patients are co-infected with HCV. Notably, the burden of HCV infection (e.g., viral persistence, viral load, or HCV-related liver symptoms) is more pronounced in the presence of HIV co-infection. However, to date, the underlying immune mechanisms accounting for accelerated disease progression in HIV/HCV-coinfected individuals have not been described in sufficient detail. We hypothesized that regulatory T cells (Treg) bearing potent immunosuppressive capacities could not only play a substantial role in the pathogenesis of HCV/HIV coinfection but also modulate the response to the standard anti-viral therapy. Materials and Methods: To this end, we studied alterations in frequencies of Treg cells in correlation with other Treg-related and virus-related parameters in both HCV and HCV/HIV-infected patients subjected to standard pegIFN-α/RBV therapy. Results: Notably, we found that pegIFN-α/RBV therapy significantly increased levels of Treg cells in HCV-infected but not in HIV/HCV-coinfected individuals. Furthermore, HIV/HCV-coinfection was demonstrated to inhibit expansion of regulatory T cells during anti-viral treatment; thus, it might probably be responsible for viral persistence and HCV-related liver damage. Conclusions: Therapy with pegIFN-α/RBV demonstrated a significant effect on regulatory T cells in the course of HIV and/or HCV infection indicating a crucial role in the anti-viral immune response.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3867-3867
Author(s):  
Dan Avi Landau ◽  
Michelle Rosenzwajg ◽  
David Saadoun ◽  
Helene Trebeden-Negre ◽  
Patrice Cacoub ◽  
...  

Abstract Background- Mixed cryoglobulinemia (MC) vasculitis is an autoimmune disorder associated with chronic hepatitis C virus (HCV) infection. We previously reported that MC vasculitis is associated with a quantitative defect of peripheral blood regulatory T cells (Tregs). We aimed to prospectively evaluate the evolution of this defect during the course of anti-viral treatment. Methods- Treg frequencies and numbers were analyzed in 131 HCV chronically infected patients (including 66 with MC vasculitis) and 20 healthy volunteers. Measurements were taken before, during and after treatment with Pegylated Interferon and Ribavirin. Findings- At baseline, patients with MC vasculitis had significantly lower frequency and number of Tregs than patients without MC vasculitis. Complete remission of MC vasculitis following anti-viral treatment was associated with a significant increase in Treg levels compared to baseline levels. In contrast, Treg levels in non- or partial-responders, which did not differ from those of complete responders at baseline, remained unchanged over the course of the study, and where significantly lower that those of complete responders. Interpretation- The strong positive correlation between clinical responses and Treg levels provides additional support for the central role of Treg cells in the pathogenesis of HCV-induced MC-vasculitis. Furthermore, it emphasizes the dual role of Treg cells in chronic HCV infection: while they may hinder viral elimination, Treg cells also have a beneficial role in limiting autoimmune tissue injury. Correlations, in MC-vasculitis patients, between CD4+CD25 high levels and response to anti-viral treatment using clinical (A+B) or laboratory (C+D) measures. CR-complete response, NR/PR-no or partial response. Correlations, in MC-vasculitis patients, between CD4+CD25 high levels and response to anti-viral treatment using clinical (A+B) or laboratory (C+D) measures. CR-complete response, NR/PR-no or partial response.


2010 ◽  
Vol 119 (2) ◽  
pp. 97-109 ◽  
Author(s):  
Bettina Langhans ◽  
Ingrid Braunschweiger ◽  
Simone Arndt ◽  
Wibke Schulte ◽  
Judith Satoguina ◽  
...  

CD4+ Treg-cells (regulatory T-cells) probably contribute to the impaired virus-specific T-cell responses in chronic HCV (hepatitis C virus) infection; however, their antigen-specificity has remained elusive. In the present study, we analysed peripheral blood CD4+ Treg-cells in patients with chronic hepatitis C and subjects with self-limited HCV infection and characterized individual Treg-cell clones obtained from both groups at the phenotypic and functional level. Foxp3 (forkhead box p3)+CD25+CD4+ Treg-cells were detected more frequently in patients with chronic hepatitis C than self-limited HCV infection, which responded to HCV core stimulation and inhibited proliferation of reporter cells. Cloning under limiting dilution conditions resulted in 14 and six hypoproliferative Foxp3+CD25+CD127−CD4+ T-cell clones from patients with chronic hepatitis C and subjects with self-limited HCV infection respectively. All clones expressed Treg-cell markers and produced IL (interleukin)-10 upon mitogen stimulation. However, exclusively Treg-cell clones from chronic hepatitis C produced IL-10 in response to HCV core and inhibited proliferation of reporter T-cells. These core-specific Treg-cell clones recognized epitopes in two regions of HCV core (amino acids 1–44 and 79–113). Co-culture inhibition assays demonstrated Treg-cells to inhibit reporter T-cells via secretion of IL-10 and IL-35 rather than cell-contact-dependent mechanisms. Finally, the HCV-specific Treg-cell clones lost their functional capacity, along with Foxp3 expression, if kept in culture without HCV core exposure. In conclusion, we identified functionally active HCV core-specific Treg-cells in patients with chronic hepatitis C, which share their epitopes with conventional T-cells and require the continued presence of antigen to maintain their functional differentiation. Thus HCV core-specific Treg-cells may contribute to the immunoregulatory balance in chronic hepatitis C.


Life ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 245
Author(s):  
Daniil Shevyrev ◽  
Valeriy Tereshchenko ◽  
Elena Blinova ◽  
Nadezda Knauer ◽  
Ekaterina Pashkina ◽  
...  

Homeostatic proliferation (HP) is a physiological process that reconstitutes the T cell pool after lymphopenia involving Interleukin-7 and 15 (IL-7 and IL-15), which are the key cytokines regulating the process. However, there is no evidence that these cytokines influence the function of regulatory T cells (Tregs). Since lymphopenia often accompanies autoimmune diseases, we decided to study the functional activity of Tregs stimulated by HP cytokines from patients with rheumatoid arthritis as compared with that of those from healthy donors. Since T cell receptor (TCR) signal strength determines the intensity of HP, we imitated slow HP using IL-7 or IL-15 and fast HP using a combination of IL-7 or IL-15 with anti-CD3 antibodies, cultivating Treg cells with peripheral blood mononuclear cells (PBMCs) at a 1:1 ratio. We used peripheral blood from 14 patients with rheumatoid arthritis and 18 healthy volunteers. We also used anti-CD3 and anti-CD3 + IL-2 stimulation as controls. The suppressive activity of Treg cells was evaluated in each case by the inhibition of the proliferation of CD4+ and CD8+ cells. The phenotype and proliferation of purified CD3+CD4+CD25+CD127lo cells were assessed by flow cytometry. The suppressive activity of the total pool of Tregs did not differ between the rheumatoid arthritis and healthy donors; however, it significantly decreased in conditions close to fast HP when the influence of HP cytokines was accompanied by anti-CD3 stimulation. The Treg proliferation caused by HP cytokines was lower in the rheumatoid arthritis (RA) patients than in the healthy individuals. The revealed decrease in Treg suppressive activity could impact the TCR landscape during lymphopenia and lead to the proliferation of potentially self-reactive T cell clones that are able to receive relatively strong TCR signals. This may be another explanation as to why lymphopenia is associated with the development of autoimmune diseases. The revealed decrease in Treg proliferation under IL-7 and IL-15 exposure can lead to a delay in Treg pool reconstitution in patients with rheumatoid arthritis in the case of lymphopenia.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mei Ding ◽  
Rajneesh Malhotra ◽  
Tomas Ottosson ◽  
Magnus Lundqvist ◽  
Aman Mebrahtu ◽  
...  

AbstractRegulatory T cells (Tregs) are the key cells regulating peripheral autoreactive T lymphocytes. Tregs exert their function by suppressing effector T cells. Tregs have been shown to play essential roles in the control of a variety of physiological and pathological immune responses. However, Tregs are unstable and can lose the expression of FOXP3 and suppressive functions as a consequence of outer stimuli. Available literature suggests that secreted proteins regulate Treg functional states, such as differentiation, proliferation and suppressive function. Identification of secreted proteins that affect Treg cell function are highly interesting for both therapeutic and diagnostic purposes in either hyperactive or immunosuppressed populations. Here, we report a phenotypic screening of a human secretome library in human Treg cells utilising a high throughput flow cytometry technology. Screening a library of 575 secreted proteins allowed us to identify proteins stabilising or destabilising the Treg phenotype as suggested by changes in expression of Treg marker proteins FOXP3 and/or CTLA4. Four proteins including GDF-7, IL-10, PAP and IFNα-7 were identified as positive regulators that increased FOXP3 and/or CTLA4 expression. PAP is a phosphatase. A catalytic-dead version of the protein did not induce an increase in FOXP3 expression. Ten interferon proteins were identified as negative regulators that reduced the expression of both CTLA4 and FOXP3, without affecting cell viability. A transcriptomics analysis supported the differential effect on Tregs of IFNα-7 versus other IFNα proteins, indicating differences in JAK/STAT signaling. A conformational model experiment confirmed a tenfold reduction in IFNAR-mediated ISG transcription for IFNα-7 compared to IFNα-10. This further strengthened the theory of a shift in downstream messaging upon external stimulation. As a summary, we have identified four positive regulators of FOXP3 and/or CTLA4 expression. Further exploration of these Treg modulators and their method of action has the potential to aid the discovery of novel therapies for both autoimmune and infectious diseases as well as for cancer.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Cristian Doñas ◽  
Macarena Fritz ◽  
Valeria Manríquez ◽  
Gabriela Tejón ◽  
María Rosa Bono ◽  
...  

Regulatory T cells are a specific subset of lymphocytes that suppress immune responses and play a crucial role in the maintenance of self-tolerance. They can be generated in the thymus as well as in the periphery through differentiation of naïve CD4+T cells. The forkhead box P3 transcription factor (Foxp3) is a crucial molecule regulating the generation and function of Tregs. Here we show that thefoxp3gene promoter becomes hyperacetylated inin vitrodifferentiated Tregs compared to naïve CD4+T cells. We also show that the histone deacetylase inhibitor TSA stimulated thein vitrodifferentiation of naïve CD4+T cells into Tregs and that this induction was accompanied by a global increase in histone H3 acetylation. Importantly, we also demonstrated that Tregs generated in the presence of TSA have phenotypical and functional differences from the Tregs generated in the absence of TSA. Thus, TSA-generated Tregs showed increased suppressive activities, which could potentially be explained by a mechanism involving the ectonucleotidases CD39 and CD73. Our data show that TSA could potentially be used to enhance the differentiation and suppressive function of CD4+Foxp3+Treg cells.


2021 ◽  
Vol 22 (21) ◽  
pp. 11977
Author(s):  
Jocelyn C. Pérez-Lara ◽  
Enrique Espinosa ◽  
Leopoldo Santos-Argumedo ◽  
Héctor Romero-Ramírez ◽  
Gabriela López-Herrera ◽  
...  

CD38 is a transmembrane glycoprotein expressed by T-cells. It has been reported that patients with systemic lupus erythematosus (SLE) showed increased CD38+CD25+ T-cells correlating with immune activation and clinical signs. Contrariwise, CD38 deficiency in murine models has shown enhanced autoimmunity development. Recent studies have suggested that CD38+ regulatory T-cells are more suppressive than CD38− regulatory T-cells. Thus, we have suggested that CD38 overexpression in SLE patients could play a role in regulating immune activation cells instead of enhancing it. This study found a correlation between CD38 with FoxP3 expression and immunosuppressive molecules (CD69, IL-10, CTLA-4, and PD-1) in T-cells from lupus-prone mice (B6.MRL-Faslpr/J). Additionally, B6.MRL-Faslpr/J mice showed a decreased proportion of CD38+ Treg cells regarding wild-type mice (WT). Furthermore, Regulatory T-Cells (Treg cells) from CD38-/- mice showed impairment in expressing immunosuppressive molecules and proliferation after stimulation through the T-cell receptor (TCR). Finally, we demonstrated an increased ratio of IFN-γ/IL-10 secretion in CD38-/- splenocytes stimulated with anti-CD3 compared with the WT. Altogether, our data suggest that CD38 represents an element in maintaining activated and proliferative Treg cells. Consequently, CD38 could have a crucial role in immune tolerance, preventing SLE development through Treg cells.


2021 ◽  
Vol 11 ◽  
Author(s):  
Lourdes Rocamora-Reverte ◽  
Franz Leonard Melzer ◽  
Reinhard Würzner ◽  
Birgit Weinberger

The immune system is a tightly regulated network which allows the development of defense mechanisms against foreign antigens and tolerance toward self-antigens. Regulatory T cells (Treg) contribute to immune homeostasis by maintaining unresponsiveness to self-antigens and suppressing exaggerated immune responses. Dysregulation of any of these processes can lead to serious consequences. Classically, Treg cell functions have been described in CD4+ T cells, but other immune cells also harbour the capacity to modulate immune responses. Regulatory functions have been described for different CD8+ T cell subsets, as well as other T cells such as γδT cells or NKT cells. In this review we describe the diverse populations of Treg cells and their role in different scenarios. Special attention is paid to the aging process, which is characterized by an altered composition of immune cells. Treg cells can contribute to the development of various age-related diseases but they are poorly characterized in aged individuals. The huge diversity of cells that display immune modulatory functions and the lack of universal markers to identify Treg make the expanding field of Treg research complex and challenging. There are still many open questions that need to be answered to solve the enigma of regulatory T cells.


2006 ◽  
Vol 3 (1) ◽  
pp. 25-30 ◽  
Author(s):  
Aristo Vojdani ◽  
Jonathan Erde

Over the past decade, great interest has been given to regulatory T (Treg) cells. A vast body of evidence has shown the existence and highlighted the importance of Treg cells in the active suppression of immune system responses. This form of immunoregulation is the dominant means utilized by the immune system to reach a harmony between reciprocal response processes in order to ensure adequate host defense with minimal host detriment. Therapeutically targeting Treg cells is a direct and powerful means to manipulate the immune system to achieve beneficial effects on various disease pathologies, including allergy, autoimmunity and cancer, as well as the facilitation of organ transplantation. This powerful target for immunoregulation is of much concern to practitioners and researchers of complementary and alternative medicine because it allows a great deal of control and certainty in dealing with the prevalence of debilitating immune system-related disorders for which there has been little remedy outside of Western Medicine.


Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1888 ◽  
Author(s):  
Jonadab E. Olguín ◽  
Itzel Medina-Andrade ◽  
Tonathiu Rodríguez ◽  
Miriam Rodríguez-Sosa ◽  
Luis I. Terrazas

In recent years, there has been a significant increase in the study of own and foreign human factors favoring the development of different types of cancer, including genetic and environmental ones. However, the fact that the immune response plays a fundamental role in the development of immunity and susceptibility to colorectal cancer (CRC) is much stronger. Among the many cell populations of the immune system that participate in restricting or favoring CRC development, regulatory T cells (Treg) play a major role in orchestrating immunomodulation during CRC. In this review, we established concrete evidence supporting the fact that Treg cells have an important role in the promotion of tumor development during CRC, mediating an increasing suppressive capacity which controls the effector immune response, and generating protection for tumors. Furthermore, Treg cells go through a process called “phenotypic plasticity”, where they co-express transcription factors that promote an inflammatory profile. We reunited evidence that describes the interaction between the different effector populations of the immune response and its modulation by Treg cells adapted to the tumor microenvironment, including the mechanisms used by Treg cells to suppress the protective immune response, as well as the different subpopulations of Treg cells participating in tumor progression, generating susceptibility during CRC development. Finally, we discussed whether Treg cells might or might not be a therapeutic target for an effective reduction in the morbidity and mortality caused by CRC.


2019 ◽  
Vol 14 (4) ◽  
pp. 508-524 ◽  
Author(s):  
Heike Schmitt ◽  
Julia Ulmschneider ◽  
Ulrike Billmeier ◽  
Michael Vieth ◽  
Patrizio Scarozza ◽  
...  

Abstract Background and Aims The topically applied Toll-like receptor 9 [TLR9] agonist cobitolimod is a first-in-class DNA-based oligonucleotide with demonstrated therapeutic efficacy in clinical trials with ulcerative colitis [UC] patients. We here characterized its anti-inflammatory mechanism in UC. Methods Luminal cobitolimod administration was evaluated in an experimental dextran sodium sulfate [DSS]-induced colitis model. Cultured blood and mucosal cells from UC patients were treated with cobitolimod and analysed via microarray, quantitative real-time PCR, ELISA and flow cytometry. Intestinal slides of cobitolimod-treated UC patients were analysed by immunohistochemistry. Results Cobitolimod administration markedly suppressed experimental colitis activity, and microarray analyses demonstrated mucosal IL10 upregulation and suppression of IL17 signalling pathways. Cobitolimod treatment was associated with significant induction of mucosal IL10+Tr1 and Treg cells and suppression of Th17 cells. TLR9 knockout mice indicated that cobitolimod requires TLR9 signalling for IL10 induction. In UC patients, mucosal TLR9 levels correlated with severity of inflammation. Cobitolimod inhibited IL17A and IL17F, but increased IL10 and FoxP3 expression in cultured intestinal UC T cells. Cobitolimod-mediated suppression of intestinal IL17+T cells was abrogated by IL10 blockade. Furthermore, cobitolimod led to heightened IL10 production by wound healing macrophages. Immunohistochemistry in intestinal biopsies of cobitolimod-treated UC patients indicated increased presence of IL10+mononuclear and regulatory T cells, as well as reduction of IL17+cells. Conclusion Activation of TLR9 via cobitolimod might represent a novel therapeutic approach in UC, as it suppresses Th17 cells and induces anti-inflammatory IL10+macrophages and regulatory T cells, thereby modifying the dysregulated intestinal cytokine balance. Podcast This article has an associated podcast which can be accessed at https://academic.oup.com/ecco-jcc/pages/podcast


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