scholarly journals Antigen Presenting B Cells Facilitate CD4 T Cell Cooperation Resulting in Enhanced Generation of Effector and Memory CD4 T Cells

PLoS ONE ◽  
2013 ◽  
Vol 8 (10) ◽  
pp. e77346 ◽  
Author(s):  
David R. Kroeger ◽  
Christopher D. Rudulier ◽  
Peter A. Bretscher
2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Stephanie M. Dillon ◽  
Tezha A. Thompson ◽  
Allison J. Christians ◽  
Martin D. McCarter ◽  
Cara C. Wilson

Abstract Background The etiology of the low-level chronic inflammatory state associated with aging is likely multifactorial, but a number of animal and human studies have implicated a functional decline of the gastrointestinal immune system as a potential driver. Gut tissue-resident memory T cells play critical roles in mediating protective immunity and in maintaining gut homeostasis, yet few studies have investigated the effect of aging on human gut T cell immunity. To determine if aging impacted CD4 T cell immunity in the human large intestine, we utilized multi-color flow cytometry to measure colonic lamina propria (LP) CD4 T cell frequencies and immune-modulatory marker expression in younger (mean ± SEM: 38 ± 1.5 yrs) and older (77 ± 1.6 yrs) adults. To determine cellular specificity, we evaluated colon LP CD8 T cell frequency and phenotype in the same donors. To probe tissue specificity, we evaluated the same panel of markers in peripheral blood (PB) CD4 T cells in a separate cohort of similarly aged persons. Results Frequencies of colonic CD4 T cells as a fraction of total LP mononuclear cells were higher in older persons whereas absolute numbers of colonic LP CD4 T cells per gram of tissue were similar in both age groups. LP CD4 T cells from older versus younger persons exhibited reduced CTLA-4, PD-1 and Ki67 expression. Levels of Bcl-2, CD57, CD25 and percentages of activated CD38+HLA-DR+ CD4 T cells were similar in both age groups. In memory PB CD4 T cells, older age was only associated with increased CD57 expression. Significant age effects for LP CD8 T cells were only observed for CTLA-4 expression, with lower levels of expression observed on cells from older adults. Conclusions Greater age was associated with reduced expression of the co-inhibitory receptors CTLA-4 and PD-1 on LP CD4 T cells. Colonic LP CD8 T cells from older persons also displayed reduced CTLA-4 expression. These age-associated profiles were not observed in older PB memory CD4 T cells. The decline in co-inhibitory receptor expression on colonic LP T cells may contribute to local and systemic inflammation via a reduced ability to limit ongoing T cell responses to enteric microbial challenge.


2020 ◽  
Vol 4 (12) ◽  
pp. 2595-2605 ◽  
Author(s):  
Ole Audun W. Haabeth ◽  
Kjartan Hennig ◽  
Marte Fauskanger ◽  
Geir Åge Løset ◽  
Bjarne Bogen ◽  
...  

Abstract CD4+ T cells may induce potent antitumor immune responses through interaction with antigen-presenting cells within the tumor microenvironment. Using a murine model of multiple myeloma, we demonstrated that adoptive transfer of idiotype-specific CD4+ T cells may elicit curative responses against established multifocal myeloma in bone marrow. This finding indicates that the myeloma bone marrow niche contains antigen-presenting cells that may be rendered tumoricidal. Given the complexity of the bone marrow microenvironment, the mechanistic basis of such immunotherapeutic responses is not known. Through a functional characterization of antitumor CD4+ T-cell responses within the bone marrow microenvironment, we found that killing of myeloma cells is orchestrated by a population of bone marrow–resident CD11b+F4/80+MHC-IIHigh macrophages that have taken up and present secreted myeloma protein. The present results demonstrate the potential of resident macrophages as powerful mediators of tumor killing within the bone marrow and provide a basis for novel therapeutic strategies against multiple myeloma and other malignancies that affect the bone marrow.


2003 ◽  
Vol 198 (12) ◽  
pp. 1909-1922 ◽  
Author(s):  
Souheil-Antoine Younes ◽  
Bader Yassine-Diab ◽  
Alain R. Dumont ◽  
Mohamed-Rachid Boulassel ◽  
Zvi Grossman ◽  
...  

CD4+ T cell responses are associated with disease control in chronic viral infections. We analyzed human immunodeficiency virus (HIV)-specific responses in ten aviremic and eight viremic patients treated during primary HIV-1 infection and for up to 6 yr thereafter. Using a highly sensitive 5-(and-6)-carboxyfluorescein diacetate-succinimidyl ester–based proliferation assay, we observed that proliferative Gag and Nef peptide-specific CD4+ T cell responses were 30-fold higher in the aviremic patients. Two subsets of HIV-specific memory CD4+ T cells were identified in aviremic patients, CD45RA− CCR7+ central memory cells (Tcm) producing exclusively interleukin (IL)-2, and CD45RA− CCR7− effector memory cells (Tem) that produced both IL-2 and interferon (IFN)-γ. In contrast, in viremic, therapy-failing patients, we found significant frequencies of Tem that unexpectedly produced exclusively IFN-γ. Longitudinal analysis of HIV epitope–specific CD4+ T cells revealed that only cells that had the capacity to produce IL-2 persisted as long-term memory cells. In viremic patients the presence of IFN-γ–producing cells was restricted to periods of elevated viremia. These findings suggest that long-term CD4+ T cell memory depends on IL-2–producing CD4+ T cells and that IFN-γ only–producing cells are short lived. Our data favor a model whereby competent HIV-specific Tcm continuously arise in small numbers but under persistent antigenemia are rapidly induced to differentiate into IFN-γ only–producing cells that lack self-renewal capacity.


2003 ◽  
Vol 197 (3) ◽  
pp. 375-385 ◽  
Author(s):  
Hiroeki Sahara ◽  
Nilabh Shastri

CD4 T cells regulate immune responses that cause chronic graft rejection and graft versus host disease but their target antigens remain virtually unknown. We developed a new method to identify CD4 T cell–stimulating antigens. LacZ-inducible CD4 T cells were used as a probe to detect their cognate peptide/MHC II ligand generated in dendritic cells fed with Escherichia coli expressing a library of target cell genes. The murine H46 locus on chromosome 7 was thus found to encode the interleukin 4–induced IL4i1 gene. The IL4i1 precursor contains the HAFVEAIPELQGHV peptide which is presented by Ab major histocompatibility complex class II molecule via an endogenous pathway in professional antigen presenting cells. Both allelic peptides bind Ab and a single alanine to methionine substitution at p2 defines nonself. These results reveal novel features of H loci that regulate CD4 T cell responses as well as provide a general strategy for identifying elusive antigens that elicit CD4 T cell responses to tumors or self-tissues in autoimmunity.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 708-708
Author(s):  
Hongwei Wang ◽  
F. Cheng ◽  
K. Wright ◽  
J. Tao ◽  
M. Smith ◽  
...  

Abstract STAT3 signaling has emerged as a negative regulator of inflammatory responses in immune cells. In bone-marrow derived antigen-presenting cells (APCs), genetic or pharmacologic disruption of STAT3 led to inflammatory cells that effectively prime antigen-specific T-cell responses and restore the responsiveness of tolerized T-cells. In contrast, enhanced Stat3 activity in APCs resulted in increased production of the immunosuppressive cytokine IL-10 and induction of T-cell tolerance1. B-cell lymphomas being tumors derived from B-lymphocytes display intrinsic antigen-presenting capabilities. Augmentation of this APC function has been shown to result in effective anti-lymphoma immunity2. In this study we determined whether targeting Stat3 signaling might influence the intrinsic APC function of malignant B-cells and the responsiveness –or not- of antigen-specific CD4+ T-cells. First, we specifically block STAT3 signaling in A20 lymphoma B-cells by using a dominant negative variant of STAT3, Stat3b. Inhibition of STAT3 resulted in tumor cells capable not only of fully priming naïve antigen-specific CD4+T-cells but also able of restoring the responsiveness of tolerant T-cells from lymphoma bearing mice. Conversely, transfection of A20 B-cells with Stat3c, a constitutively activated mutant form of STAT3, led to T-cell unresponsiveness. Of note, manipulation of STAT3 in B cell tumors was associated with changes in the mRNA expression and protein levels of IL-10. Second, we evaluated the effects of two novel Stat3 inhibitors, CPA-7 (a platinum-containing compound that disrupts STAT3 DNA binding activity) and S3I-201 (inhibitor of Stat3:Stat3 complex formation and Stat3 DNA binding and transcriptional activities) in a murine model of Mantle Cell Lymphoma (MCL). In vitro treatment of FC-muMCL1 cells - derived from a tumor elicited in Em-Cyclin D1 transgenic mice- with increasing concentrations of either CPA-7 or S3I-201 resulted in an enhanced presentation of OVA-peptide to naïve CD4+ T-cells specific for a MHC class II restricted epitope of ovalbumin (OT-II cells). Indeed, these T-cells produce higher levels of IL-2 and IFN-gamma compared to anti-OVA T cells that encountered cognate antigen in untreated FC-muMCL1 cells. More importantly, MCL cells treated with CPA-7 restored the responsiveness of tolerized anti-OVA CD4+ T-cells. Finally, in vivo treatment of MCL-bearing mice with CPA-7 (5 mg/kg/iv given on days +21, +24 and +27 after tumor challenge) resulted in significant inhibition of p-Stat3 in malignant B-cells and augmentation of their APC function. Taken together, STAT3 signaling is involved in the regulation of the antigen-presenting capabilities of B-cell lymphomas and as such represents a novel molecular target to augment the immunogenicity of these tumors.


2004 ◽  
Vol 173 (1) ◽  
pp. 673-681 ◽  
Author(s):  
Insoo Kang ◽  
Myung Sun Hong ◽  
Helena Nolasco ◽  
Sung Hwan Park ◽  
Jin Myung Dan ◽  
...  

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1071-1071
Author(s):  
Yingyu Chen ◽  
Xiaofeng Luo ◽  
Juan Chen ◽  
Jocelyn Schroeder ◽  
Christina K Baumgartner ◽  
...  

Abstract Immune response to factor VIII (FVIII) is not only a severe complication in protein replacement therapy, but also a major concern in gene therapy of hemophilia A. Our previous studies have demonstrated that platelet-targeted FVIII (2bF8) gene therapy together with in vivo drug-selection of transduced cells can not only rescue the bleeding diathesis but also induce anti-FVIII specific immune tolerance in FVIIInull mice. In the current study, we investigated 1) whether our non-selectable lentiviral vector (LV) for the induction of platelet-FVIII expression is sufficient to induce immune tolerance and 2) which cell compartment is tolerized after platelet gene therapy. Platelet-specific FVIII expression was introduced by 2bF8LV-transduction of hematopoietic stem cells followed by syngeneic transplantation into FVIIInull mice preconditioned with 660 cGy total body irradiation (TBI) or Busulfan (Bu) plus ATG (anti-thymocyte globulin). After bone marrow transplantation and reconstitution, animals were analyzed by PCR, qPCR, FVIII:C assay, and tail clipping test to confirm the success of 2bF8 gene therapy. Sixteen weeks after transplantation, animals were challenged with recombinant human FVIII (rhF8) via retro-orbital venous administration at a dose of 50 U/kg weekly for 4 weeks. The titers of anti-FVIII inhibitory antibodies (inhibitors) were determined by Bethesda assay. The CFSE-labeled CD4 T cell proliferation assay and ELISPOT-based memory B cell maturation assay were used to determine which cell compartment is tolerized to FVIII after 2bF8 gene therapy. The level of platelet-FVIII expression was 1.44 ± 0.39 mU/108 platelets (n = 6) in the 660 cGy group, which is not significantly different from the level obtained from the Bu+ATG group [3.04 ± 1.19 mU/108 platelets (n = 6)]. Even after rhF8 challenge, no antibodies were detected in 2bF8LV-transduced recipients in either group. In contrast, all animals in the control group that did not undergo gene therapy developed various levels of inhibitors (204±97 BU/ml, n=7). The frequency of regulatory T cells in both 660 cGy TBI (11.01±0.52%) and Bu+ATG (11.02±0.68%) groups were significantly higher than the control group (8.05±0.57%). T cell proliferation assay demonstrated that CD4+ T cells from 2bF8 LV-transduced recipients that had been challenged with rhF8 did not proliferate when restimulated with rhF8 in vitro. The daughter CD4+ T cells in the group with 10 U/ml of rhF8 were 5.84 ± 2.49% (n = 6), which was not significantly different from the control group without no rhF8 stimulation (0 U/ml) (5.33 ± 1.72%). CD4+ T cells from primed FVIIInull mice did proliferate after rhF8 restimulation. The proliferated daughter cell was 13.12 ± 6.76% (n = 7) in the group with rhF8 (10 U/ml) re-stimulation, which is significantly higher than the group without rhF8 co-culture (4.99 ± 1.16%). Since FVIII-specific memory B cell maturation is CD4+ T cell dependent, we isolated CD4+ T and memory B cells from 2bF8LV-transduced or FVIIInull mice after rhF8 immunization and co-cultured with rhF8 followed by ELISPOT assay to examine the antibody secreting cells. No spots were detected when memory B cells from rhF8-primed FVIIInull mice were co-cultured with CD4+ T cells from 2bF8LV-transduced recipients. In contrast, when memory B cells from either rhF8 immunized 2bF8LV-transduced or untreated FVIIInull mice were cultured with CD4+ T cells from rhF8-primed FVIIInull mice, there were 142 and 205 anti-FVIII antibody secreting cells, respectively, detected per 106 cells seeded. These results indicate that CD4+ T cells from 2bF8LV-transduced mice are tolerized to rhF8 stimulation. In conclusion, 2bF8 lentiviral gene transfer without in vivo selection of genetically manipulated cells can introduce FVIII-specific immune tolerance in hemophilia A mice and this immune tolerance is CD4+ T cell-mediated. Disclosures Baumgartner: Novo Nordisk: Research Funding. Shi:BloodCenter of Wisconsin: Patents & Royalties: METHOD OF INDUCING IMMUNE TOLERANCE THROUGH TARGETTED GENE EXPRESSION..


2021 ◽  
Vol 17 (4) ◽  
pp. e1009522
Author(s):  
Orion Tong ◽  
Gabriel Duette ◽  
Thomas Ray O’Neil ◽  
Caroline M. Royle ◽  
Hafsa Rana ◽  
...  

Although HIV infection inhibits interferon responses in its target cells in vitro, interferon signatures can be detected in vivo soon after sexual transmission, mainly attributed to plasmacytoid dendritic cells (pDCs). In this study, we examined the physiological contributions of pDCs to early HIV acquisition using coculture models of pDCs with myeloid DCs, macrophages and the resting central, transitional and effector memory CD4 T cell subsets. pDCs impacted infection in a cell-specific manner. In myeloid cells, HIV infection was decreased via antiviral effects, cell maturation and downregulation of CCR5 expression. In contrast, in resting memory CD4 T cells, pDCs induced a subset-specific increase in intracellular HIV p24 protein expression without any activation or increase in CCR5 expression, as measured by flow cytometry. This increase was due to reactivation rather than enhanced viral spread, as blocking HIV entry via CCR5 did not alter the increased intracellular p24 expression. Furthermore, the load and proportion of cells expressing HIV DNA were restricted in the presence of pDCs while reverse transcriptase and p24 ELISA assays showed no increase in particle associated reverse transcriptase or extracellular p24 production. In addition, PDCs also markedly induced the expression of CD69 on infected CD4 T cells and other markers of CD4 T cell tissue retention. These phenotypic changes showed marked parallels with resident memory CD4 T cells isolated from anogenital tissue using enzymatic digestion. Production of IFNα by pDCs was the main driving factor for all these results. Thus, pDCs may reduce HIV spread during initial mucosal acquisition by inhibiting replication in myeloid cells while reactivating latent virus in resting memory CD4 T cells and retaining them for immune clearance.


Vaccines ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1439
Author(s):  
Kevin M. Dennehy ◽  
Eva Löll ◽  
Christine Dhillon ◽  
Johanna-Maria Classen ◽  
Tobias D. Warm ◽  
...  

Memory T-cell responses following infection with coronaviruses are reportedly long-lived and provide long-term protection against severe disease. Whether vaccination induces similar long-lived responses is not yet clear since, to date, there are limited data comparing memory CD4+ T-cell responses induced after SARS-CoV-2 infection versus following vaccination with BioNTech/Pfizer BNT162b2. We compared T-cell immune responses over time after infection or vaccination using ELISpot, and memory CD4+ T-cell responses three months after infection/vaccination using activation-induced marker flow cytometric assays. Levels of cytokine-producing T-cells were remarkably stable between three and twelve months after infection, and were comparable to IFNγ+ and IFNγ+IL-2+ T-cell responses but lower than IL-2+ T-cell responses at three months after vaccination. Consistent with this finding, vaccination and infection elicited comparable levels of SARS-CoV-2 specific CD4+ T-cells after three months in addition to comparable proportions of specific central memory CD4+ T-cells. By contrast, the proportions of specific effector memory CD4+ T-cells were significantly lower, whereas specific effector CD4+ T-cells were higher after infection than after vaccination. Our results suggest that T-cell responses—as measured by cytokine expression—and the frequencies of SARS-CoV-2-specific central memory CD4+T-cells—indicative of the formation of the long-lived memory T-cell compartment—are comparably induced after infection and vaccination.


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