scholarly journals Granulocytic myeloid-derived suppressor cells inhibit T follicular helper cells during experimental Schistosoma japonicum infection

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Yumei Zhang ◽  
Yulong Wu ◽  
Hua Liu ◽  
Wenci Gong ◽  
Yuan Hu ◽  
...  

Abstract Background CD4+ T helper (Th) cells play critical roles in both host humoral and cellular immunity against parasitic infection and in the immunopathology of schistosomiasis. T follicular helper (Tfh) cells are a specialized subset of Th cells involved in immunity against infectious diseases. However, the role of Tfh cells in schistosome infection is not fully understood. In this study, the dynamics and roles of Tfh cell regulation were examined. We demonstrated that granulocytic myeloid-derived suppressor cells (G-MDSC) can suppress the proliferation of Tfh cells. Methods The levels of Tfh cells and two other Th cells (Th1, Th2) were quantitated at different Schistosoma japonicum infection times (0,3, 5, 8, 13 weeks) using flow cytometry. The proliferation of Tfh cells stimulated by soluble egg antigen (SEA) and soluble worm antigen (SWA) in vivo and in vitro were analyzed. Tfh cells were co-cultured with MDSC to detect the proliferation of Tfh cells labelled by 5(6)-carboxyfluorescein diacetate N-succinimidyl ester. We dynamically monitored the expression of programmed cell death protein 1 (PD-1) on the surface of Tfh cells and programmed cell death ligand 1 (PD-L1) on the surface of MDSC at different infection times (0, 3, 5, 8 weeks). Naïve CD4+ T cells (in Tfh cell differentiation) were co-cultured with G-MDSC or monocytic MDSC in the presence, or in the absence, of PD-L1 blocking antibody. Results The proportion of Tfh cells among CD4+ T cells increased gradually with time of S. japonicum infection, reaching a peak at 8 weeks, after which it decreased gradually. Both SEA and SWA caused an increase in Tfh cells in vitro and in vivo. It was found that MDSC can suppress the proliferation of Tfh cells. The expression of PD-1 on Tfh cells and PD-L1 from MDSC cells increased with prolongation of the infection cycle. G-MDSC might regulate Tfh cells through the PD-1/PD-L1 pathway. Conclusions The reported study not only reveals the dynamics of Tfh cell regulation during S. japonicum infection, but also provides evidence that G-MDSC may regulate Tfh cells by PD-1/PD-L1. This study provides strong evidence for the important role of Tfh cells in the immune response to S. japonicum infection. Graphical abstract

Author(s):  
Mohammad H. Rashid ◽  
Thaiz F. Borin ◽  
Roxan Ara ◽  
Raziye Piranlioglu ◽  
Bhagelu R. Achyut ◽  
...  

AbstractMyeloid-derived suppressor cells (MDSCs) are an indispensable component of the tumor microenvironment (TME), and our perception regarding the role of MDSCs in tumor promotion is attaining extra layer of intricacy in every study. In conjunction with MDSC’s immunosuppressive and anti-tumor immunity, they candidly facilitate tumor growth, differentiation, and metastasis in several ways that yet to be explored. Alike any other cell types, MDSCs also release a tremendous amount of exosomes or nanovesicles of endosomal origin and partake in intercellular communications by dispatching biological macromolecules. There has not been any experimental study done to characterize the role of MDSCs derived exosomes (MDSC exo) in the modulation of TME. In this study, we isolated MDSC exo and demonstrated that they carry a significant amount of proteins that play an indispensable role in tumor growth, invasion, angiogenesis, and immunomodulation. We observed higher yield and more substantial immunosuppressive potential of exosomes isolated from MDSCs in the primary tumor area than those are in the spleen or bone marrow. Our in vitro data suggest that MDSC exo are capable of hyper activating or exhausting CD8 T-cells and induce reactive oxygen species production that elicits activation-induced cell death. We confirmed the depletion of CD8 T-cells in vivo by treating the mice with MDSC exo. We also observed a reduction in pro-inflammatory M1-macrophages in the spleen of those animals. Our results indicate that immunosuppressive and tumor-promoting functions of MDSC are also implemented by MDSC-derived exosomes which would open up a new avenue of MDSC research and MDSC-targeted therapy.


Lupus ◽  
2017 ◽  
Vol 27 (1) ◽  
pp. 49-59 ◽  
Author(s):  
X Yang ◽  
J Yang ◽  
X Li ◽  
W Ma ◽  
H Zou

Background The objective of this paper is to analyze the role of bone marrow-derived mesenchymal stem cells (BM-MSCs) on the differentiation of T follicular helper (Tfh) cells in lupus-prone mice. Methods Bone marrow cells were isolated from C57BL/6 (B6) mice and cultured in vitro, and surface markers were identified by flow cytometry. Naïve CD4+ T cells, splenocytes and Tfh cells were isolated from B6 mice spleens and co-cultured with BM-MSCs. The proliferation and the differentiation of CD4+ T cells and Tfh cells were analyzed by flow cytometry. Lupus-prone MRL/Mp-lpr/lpr (MRL/lpr) mice were treated via intravenous injection with expanded BM-MSCs, the differentiation of Tfh cells was detected, and the relief of lupus nephritis was analyzed. Results MSCs could be successfully induced from bone marrow cells, and cultured BM-MSCs could inhibit T cell proliferation dose-dependently. BM-MSCs could prevent Tfh cell development from naïve CD4+ T cells and splenocytes. BM-MSCs could inhibit IL-21 gene expression and cytokine production and inhibit isolated Tfh cells and STAT3 phosphorylation. In vivo study proved that BM-MSCs intravenous injection could effectively inhibit Tfh cell expansion and IL-21 production, alleviate lupus nephritis, and prolong the survival rate of lupus-prone mice. Conclusions BM-MSCs could effectively inhibit the differentiation of Tfh cells both in vitro and in vivo. BM-MSC treatment could relieve lupus nephritis, which indicates that BM-MSCs might be a promising therapeutic method for the treatment of SLE.


2011 ◽  
Vol 29 (4_suppl) ◽  
pp. 194-194
Author(s):  
M. R. Porembka ◽  
J. B. Mitchem ◽  
P. S. Goedegebuure ◽  
D. Linehan

194 Background: Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immunosuppressive cells that are upregulated in cancer. Little is known about the prevalence and importance of MDSC in pancreas adenocarcinoma (PA). Here, we quantify MDSC prevalence in patients with PA and assess the efficacy of MDSC depletion in a murine model of PA. Methods: Peripheral blood and tumor samples were collected from patients with PA, analyzed for MDSC (CD15+11b+) by flow cytometry (FC) and compared to cancer-free controls (CFC). The suppressive capacity of MDSC and the effectiveness of MDSC depletion were assessed in C57BL/6 mice inoculated with Pan02, a murine PA, and treated with placebo or zoledronic acid (ZA), a potent aminobisphosphonate previously shown to target MDSC. Endpoints included tumor size, survival, and MDSC prevalence. Tumor cell infiltrate was analyzed by FC for MDSC (Gr1+CD11b+) and effector T cells; tumor cytokine levels were measured by Luminex assay. Results: Patients with PA demonstrated increased circulating MDSC compared to CFC, which correlated with disease stage (metastatic PA: 68%±3.6% of CD45+ cells, resectable PA: 57%±3.5%, CFC: 37%±3.6%; p<0.0001). Normal pancreas tissue showed no MDSC infiltrate while PA avidly recruited CD11b+15+ cells to the primary tumor. Murine tumors similarly recruited MDSC that actively suppressed CD8+ T cells in vitro measured by CFSE dilution and accelerated tumor growth in vivo by adoptive transfer with Pan02 cells (p<0.001). Treatment with ZA impaired MDSC accumulation in the tumor (Placebo: 78%, ZA: 51%, p<0.05) resulting in delayed tumor growth rate (p<0.0001) and prolonged median survival (Placebo: 59 days, ZA: 73 days, p<0.05). MDSC blockade increased recruitment of T cells to the tumor (CD4: 4.4%±1.1% vs 12.2%±2.0%, p<0.05; CD8: 3.9%±1.3% vs 10.6%±2.2%, p<0.05) and a more robust type 1 response with increased levels of IFN-g (p<0.05) and decreased levels of IL-10 (p<0.05). Conclusions: MDSC are an important mediator of tumor-induced immunosuppression in PA. Treatment with ZA effectively blocks MDSC accumulation improving anti-tumor response in animal studies. Efforts to block MDSC may represent a novel treatment strategy for PA. [Table: see text]


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 792-792
Author(s):  
Alice Mui ◽  
Mike Kennah ◽  
Christopher Ong ◽  
Raymond Anderson ◽  
Heather Sutherland

Abstract Abstract 792 We recently described a novel anti-MM drug (AQX-MN100) which is a small molecule agonist of SHIP (Src homology-2 (SH2) containing inositol-5¢-phosphatase) a signaling molecule found only in hemopoietic cells.(Ong et al, Blood; 110:1942, 2007) The molecule was developed using a high-throughput SHIP enzyme assay to screen an invertebrate marine natural product library and isolate the Pelorol.(Yang et al Org Lett; 7:1073, 2005) SHIP normally functions to negatively regulate the PI3K pathway important to normal hemopoietic cells growth and function. Inappropriate activation of the phosphoinositide 3- kinase (PI3K) pathway has been shown to be involved in the pathogenesis of MM and tumour aggressiveness correlates with the degree of activation. The critical role the PI3K/Akt signaling pathway plays in regulating MM cell survival, has stimulated efforts in designing therapeutics that target this pathway. Pan PI3K inhibitors have limited utility in a clinical setting because of their inhibitory effects on all isoforms of the PI3K family as well as non-PI3K targets. SHIP is an exceptionally good target for MM and other hematopoietic disorders that display elevated PI3K/Akt signaling because its expression is restricted to hemopoietic cells. We have shown that an analogue of Pelorol, AQX-MN100 is able to inhibit PI3K signaling and prevent phosphorylation of Akt. AQX-MN100 induced MM cell line apoptosis mediated by caspase and was specific for SHIP expressing cells which are exclusively hematopoietic. AQX-MN100 also enhances the growth inhibition effects of current myeloma drugs Dexamethasone and Bortezomib on human MM tumour cell lines in vitro. (Kennah et al Expt Hematol; 37:1274, 2009) In this study we have extended these finding to further evaluate the role of this compound in the treatment of myeloma. NOD-SCID mice were injected in the lateral flanks with 2 million luciferase tagged MM1.S multiple myeloma cells in Matrigel. Tumors were allowed to establish for two weeks and then either AQX-MN100 or vehicle was administered in an oil deposit subcutaneously in the lower flank at a dose of 50 mg/kg every three days. Tumor volume was quantified by imaging on a Xenogen IVIS 200 after 6 and 11 days. These studies demonstrate a significant reduction of tumor volume at 6 days p<0.05 and a highly significant reduction at 11 days p<0.01 in the mice receiving AQX-MN100 as compared to vehicle. We have shown that AQX-MN100 can directly kill MM cells in in vitro and in vivo. However, based on the known functions of SHIP, we predict that SHIP agonists will additionally target critical steps in MM pathogenesis in vivo, including the ability of MM cells to interact with stromal elements and to subvert the immune system. In order to evaluate this later feature we evaluated the ability of SHIP agonists to reverse the tumor associated immune suppression in MM patients. Tumor and host cell/tumor microenvironment secreted factors promote the production and activation of cells associated with cancer progression: the immune suppressive myeloid derived suppressor cells (MDSC) and regulatory T cells (Tregs). These cells normally regulate immune responses by inhibiting the activation of immune effector cells. The involvement of SHIP in the regulation of these cells is predicted by the observation that MDSC and Treg numbers are elevated in SHIP deficient mice. In this study Balb/C mice, 6 mice/group in duplicate were given either AQX-MN100 3 mg/kg and 10 mg/kg or vehicle once daily orally. At the end of three weeks mesenteric lymph nodes were harvested and subjected to FACS analysis to determine the proportion of MDSC (CD11b+Gr1+) and Treg (CD4+CD25+FoxP3+) cells. Spleen cells were also analysed for B cells, NK cells and granulocytes. In both of the AQX-MN100 treated groups the numbers of MDSC and Tregs were significantly lower than controls while Total CD11b, Total CD3, and spleen B, NK and granulocytes were not different from vehicle treated controls. The known role of SHIP in regulating hemopoietic cell function and the role of SHIP agonists in MM cell killing as well as additional actions on other aspects of MM pathophysiology may make them a powerful treatment option for MM, either alone or in synergy with other known MM therapies. Further development of this agent for the treatment of MM is ongoing. Disclosures: Mui: Aquinox: Equity Ownership, Patents & Royalties. Ong:Aquinox: Equity Ownership, Patents & Royalties. Anderson:Aquinox: Equity Ownership, Patents & Royalties. Sutherland:Celgene: Honoraria; Orthobiotech: Honoraria.


2021 ◽  
Author(s):  
Hanna S. Hong ◽  
Nneka E. Mbah ◽  
Mengrou Shan ◽  
Kristen Loesel ◽  
Lin Lin ◽  
...  

AbstractApoptotic cell death is a cell-intrinsic, immune tolerance mechanism that regulates the magnitude and resolution of T cell-mediated responses. Evasion of apoptosis is critical for the generation of memory T cells, as well as autoimmune T cells, and knowledge of the mechanisms that enable resistance to apoptosis will provide insight into ways to modulate their activity during protective and pathogenic responses. IL-17-producing CD4 T cells (TH17s) are long-lived, memory cells. These features enable their role in host defense, chronic inflammatory disorders, and anti-tumor immunity. A growing number of reports now indicate that TH17s in vivo require mitochondrial oxidative phosphorylation (OXPHOS), a metabolic phenotype that is poorly induced in vitro. To elucidate the role of OXPHOS in TH17 processes, we developed a system to polarize TH17s that metabolically resembled their in vivo counterparts. We discovered that directing TH17s to use OXPHOS promotes mitochondrial fitness, glutamine anaplerosis, and an anti-apoptotic phenotype marked by high BCL-XL and low BIM. Through competitive co-transfer experiments and tumor studies, we further revealed how OXPHOS protects TH17s from cell death while enhancing their persistence in the periphery and tumor microenvironment. Together, our work demonstrates a non-classical role of metabolism in regulating TH17 cell fate and highlights the potential for therapies that target OXPHOS in TH17-driven diseases.


Blood ◽  
2012 ◽  
Vol 119 (17) ◽  
pp. 3997-4008 ◽  
Author(s):  
Cindy S. Ma ◽  
Danielle T. Avery ◽  
Anna Chan ◽  
Marcel Batten ◽  
Jacinta Bustamante ◽  
...  

Abstract T follicular helper (Tfh) cells are critical for providing the necessary signals to induce differentiation of B cells into memory and Ab-secreting cells. Accordingly, it is important to identify the molecular requirements for Tfh cell development and function. We previously found that IL-12 mediates the differentiation of human CD4+ T cells to the Tfh lineage, because IL-12 induces naive human CD4+ T cells to acquire expression of IL-21, BCL6, ICOS, and CXCR5, which typify Tfh cells. We have now examined CD4+ T cells from patients deficient in IL-12Rβ1, TYK2, STAT1, and STAT3 to further explore the pathways involved in human Tfh cell differentiation. Although STAT1 was dispensable, mutations in IL12RB1, TYK2, or STAT3 compromised IL-12–induced expression of IL-21 by human CD4+ T cells. Defective expression of IL-21 by STAT3-deficient CD4+ T cells resulted in diminished B-cell helper activity in vitro. Importantly, mutations in STAT3, but not IL12RB1 or TYK2, also reduced Tfh cell generation in vivo, evidenced by decreased circulating CD4+CXCR5+ T cells. These results highlight the nonredundant role of STAT3 in human Tfh cell differentiation and suggest that defective Tfh cell development and/or function contributes to the humoral defects observed in STAT3-deficient patients.


1979 ◽  
Vol 149 (3) ◽  
pp. 592-600 ◽  
Author(s):  
C Bona ◽  
W E Paul

An idiotype of the dinitrophenyl-binding myeloma protein MOPC 460 was expressed on a small but significant proportion of anti-TNP antibodies which appeared after in vivo or in vitro immunization of BALB/c mice with three T-independent TNP antigens. In vitro experiments show that the depletion of T cells before culture increased significantly the number of plaques secreting anti-TNP antibodies bearing MOPC 460 idiotype (460Id). T cells from BALB/c mice, but not from C.B20 mice, exhibit this suppressor activity. Plate-binding experiments indicate that the suppressive action of the T-lymphocyte population depends on a cell which can bind to MOPC 460 myeloma protein. The possible role of these normally occurring, idiotype-specific T cells on expression of 460Id in the anti-TNP antibody response of BALB/c mice is discussed.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 438-438
Author(s):  
Anthos Christofides ◽  
Carol Cao ◽  
Qi Wang ◽  
Natalia M Tijaro-Ovalle ◽  
Eirini Konstantinidou ◽  
...  

Abstract Peroxisome proliferator activated receptors (PPARs) are transcription factors that belong to nuclear hormone superfamily, with three distinct types identified: PPARapha (PPARα), PPARgamma (PPARγ), and PPARbeta/delta (PPARβ/δ). PPARs possess a critical role in the regulation of lipid metabolism, and thus play critical roles in the differentiation and fate of immune cells. PPARα is involved in lipid and carbohydrate metabolism and PPARα agonists, such as fibrates, have been used for the treatment of hypertriglyceridemia and cardiovascular diseases. PPARα has an anti-inflammatory role during infection, and similar to PPARγ, affects the polarization of macrophages. In acute myelogenous leukemia (AML), PPARα mutations correlate with chemoresistance, poor treatment outcomes and unfavorable prognosis. In experimental tumor models, it has been proposed that PPARα agonists might enhance anti-tumor T cell responses during PD-1 blocking immunotherapy. To dissect the mechanistic role of PPARα in tumor immunity, we used mice with global deletion of PPARα and examined tumor growth and profile of the immunological landscape, using various syngeneic tumor models. Significantly larger B16-F10 melanoma and MC-17 fibrosarcoma tumors were observed in PPARα KO mice compared with wild-type control, suggesting that PPARα deletion attenuated the immunological response against cancer. To dissect the role of PPARα in key populations of the innate and adaptive immune system involved in anti-tumor responses, we analyzed the immunological landscape of tumor, tumor draining lymph nodes (TDLN) and spleen, 14-16 days after tumor implantation. Assessment of CD4 + and CD8 + T cells, CD11b +F4/80 + tumor-associated macrophages (TAMs), CD11b +Ly6C hiLy6G - monocytic myeloid derived suppressor cells (M-MDSC), and CD11b +Ly6C loLy6G + polymorphonuclear myeloid derived suppressor cells (PMN-MDSC), by using flow cytometry, showed no quantitative differences between the two experimental groups. Functionally, MDSC from PPARα KO and WT mice showed comparable immunosuppressive properties as determined by suppression assay using splenocytes from OTI transgenic mice. However, PPARα KO TAMs demonstrated a less activated state, as determined by the lower expression levels of MHC-II that is critical for antigen presentation, and CD86 that is critical for T cell costimulation and prevention of T cell anergy and exhaustion. In agreement with these properties of TAMs, CD4 + T cells from TDLN of PPARα KO mice had diminished expression of activation markers, including PD-1, PD-L1 and ICOS, and numerically decreased central memory-like CD4 + T cells (T CM), compared to control tumor bearing mice. Furthermore, CD69, an emerging marker of T cell exhaustion, was significantly upregulated in CD4 + and CD8 + T cells from the TDLN of PPARα KO mice. To determine whether PPARα ablation altered the cell intrinsic properties of myeloid cells and/or T cells resulting in impaired anti-tumor function, we examined in vitro responses of isolated populations. In response to activation via TCR/CD3 and CD28, PPARα deficient T cells had no significant differences in expansion and cytokine production compared to control. In contrast, PPARα deficient Ly6C + monocytes isolated from the bone marrow displayed diminished responses to TLR-mediated signaling as determined by production of IL-6 and TNFα. Our in vitro and in vivo findings reveal a dominant role of PPARα in regulating the fate of innate immune cells thereby altering T cell responses and anti-tumor function. Our findings have implications for the development of new therapeutic approaches to enhance innate immune cell function for the improvement of cancer immunotherapy. Disclosures No relevant conflicts of interest to declare.


2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Lan Jin ◽  
Yunhe Chen ◽  
Dan Cheng ◽  
Zhikai He ◽  
Xinyi Shi ◽  
...  

AbstractColorectal cancer (CRC) is one of the most aggressive and lethal cancers. The role of autophagy in the pathobiology of CRC is intricate, with opposing functions manifested in different cellular contexts. The Yes-associated protein (YAP), a transcriptional coactivator inactivated by the Hippo tumor-suppressor pathway, functions as an oncoprotein in a variety of cancers. In this study, we found that YAP could negatively regulate autophagy in CRC cells, and consequently, promote tumor progression of CRC in vitro and in vivo. Mechanistically, YAP interacts with TEAD forming a complex to upregulate the transcription of the apoptosis-inhibitory protein Bcl-2, which may subsequently facilitate cell survival by suppressing autophagy-related cell death; silencing Bcl-2 expression could alleviate YAP-induced autophagy inhibition without affecting YAP expression. Collectively, our data provide evidence for YAP/Bcl-2 as a potential therapeutic target for drug exploration against CRC.


Sign in / Sign up

Export Citation Format

Share Document