scholarly journals Induction of interleukin 12 responsiveness is impaired in anergic T lymphocytes.

1994 ◽  
Vol 179 (3) ◽  
pp. 1065-1070 ◽  
Author(s):  
H Quill ◽  
A Bhandoola ◽  
G Trinchieri ◽  
J Haluskey ◽  
D Peritt

The cytokine, interleukin 12 (IL-12), stimulates both natural killer cells and T cells to proliferate and to secrete interferon gamma (IFN-gamma). The T cell proliferative response to IL-12 must be induced and is evident after T cell receptor-mediated stimulation. As reported here, tolerant CD4+ T cells and clones, that are anergic for IL-2 production, are also anergic for induction of the proliferative response to IL-12. Murine T helper 1 clones tolerized in vitro, as well as anergic CD4+ T cells isolated from mice tolerized to the Mls-1a antigen (Ag) in vivo, demonstrated defective induction of proliferation to IL-12 upon restimulation with Ag. IL-12-enhanced production of IFN-gamma was observed in both control and anergic cells after Ag/antigen-presenting cell (APC) activation, although total IFN-gamma secretion by anergic cells was less than that produced by control cells, even in the presence of IL-12. These data indicate that T cell clonal anergy results in profound inhibition of proliferative responses, since the autocrine growth factor, IL-2, is not produced, and the APC-derived cytokine, IL-12, is not an effective stimulus for anergic T cell proliferation.

1994 ◽  
Vol 179 (2) ◽  
pp. 447-456 ◽  
Author(s):  
S L Reiner ◽  
S Zheng ◽  
Z E Wang ◽  
L Stowring ◽  
R M Locksley

Leishmania major are intramacrophage parasites whose eradication requires the induction of T helper 1 (Th1) effector cells capable of activating macrophages to a microbicidal state. Interleukin 12 (IL-12) has been recently identified as a macrophage-derived cytokine capable of mediating Th1 effector cell development, and of markedly enhancing interferon gamma (IFN-gamma) production by T cells and natural killer cells. Infection of macrophages in vitro by promastigotes of L. major caused no induction of IL-12 p40 transcripts, whereas stimulation using heat-killed Listeria or bacterial lipopolysaccharide induced readily detectable IL-12 mRNA. Using a competitor construct to quantitate a number of transcripts, a kinetic analysis of cytokine induction during the first few days of infection by L. major was performed. All strains of mice examined, including susceptible BALB/c and resistant C57BL/6, B10.D2, and C3H/HeN, had the appearance of a CD4+ population in the draining lymph nodes that contained transcripts for IL-2, IL-4, and IFN-gamma (and in some cases, IL-10) that peaked 4 d after infection. In resistant mice, the transcripts for IL-2, IL-4, and IL-10 were subsequently downregulated, whereas in susceptible BALB/c mice, these transcripts were only slightly decreased, and IL-4 continued to be reexpressed at high levels. IL-12 transcripts were first detected in vivo by 7 d after infection, consistent with induction by intracellular amastigotes. Challenge of macrophages in vitro confirmed that amastigotes, in contrast to promastigotes, induced IL-12 p40 mRNA. Reexamination of the cytokine mRNA at 4 d revealed expression of IL-13 in all strains analyzed, suggesting that IL-2 and IL-13 may mediate the IL-12-independent production of IFN-gamma during the first days after infection. Leishmania have evolved to avoid inducing IL-12 from host macrophages during transmission from the insect vector, and cause a striking induction of mRNAs for IL-2, IL-4, IL-10, and IL-13 in CD4+ T cells. Each of these activities may favor survival of the organism.


2000 ◽  
Vol 191 (3) ◽  
pp. 541-550 ◽  
Author(s):  
Zhengbin Lu ◽  
Lingxian Yuan ◽  
Xianzheng Zhou ◽  
Eduardo Sotomayor ◽  
Hyam I. Levitsky ◽  
...  

In many cases, induction of CD8+ CTL responses requires CD4+ T cell help. Recently, it has been shown that a dominant pathway of CD4+ help is via antigen-presenting cell (APC) activation through engagement of CD40 by CD40 ligand on CD4+ T cells. To further study this three cell interaction, we established an in vitro system using dendritic cells (DCs) as APCs and influenza hemagglutinin (HA) class I and II peptide–specific T cell antigen receptor transgenic T cells as cytotoxic T lymphocyte precursors and CD4+ T helper cells, respectively. We found that CD4+ T cells can provide potent help for DCs to activate CD8+ T cells when antigen is provided in the form of either cell lysate, recombinant protein, or synthetic peptides. Surprisingly, this help is completely independent of CD40. Moreover, CD40-independent CD4+ help can be documented in vivo. Finally, we show that CD40-independent T cell help is delivered through both sensitization of DCs and direct CD4+–CD8+ T cell communication via lymphokines. Therefore, we conclude that CD4+ help comprises at least three components: CD40-dependent DC sensitization, CD40-independent DC sensitization, and direct lymphokine-dependent CD4+–CD8+ T cell communication.


1994 ◽  
Vol 179 (4) ◽  
pp. 1273-1283 ◽  
Author(s):  
R Manetti ◽  
F Gerosa ◽  
M G Giudizi ◽  
R Biagiotti ◽  
P Parronchi ◽  
...  

Interleukin 12 (IL-12) facilitates the generation of a T helper type 1 (Th1) response, with high interferon gamma (IFN-gamma) production, while inhibiting the generation of IL-4-producing Th2 cells in polyclonal cultures of both human and murine T cells and in vivo in the mouse. In this study, we analyzed the effect of IL-12, present during cloning of human T cells, on the cytokine profile of the clones. The culture system used allows growth of clones from virtually every T cell, and thus excludes the possibility that selection of precommitted Th cell precursors plays a role in determining characteristics of the clones. IL-12 present during the cloning procedures endowed both CD4+ and CD8+ clones with the ability to produce IFN-gamma at levels severalfold higher than those observed in clones generated in the absence of IL-12. This priming was stable because the high levels of IFN-gamma production were maintained when the clones were cultured in the absence of IL-12 for 11 d. The CD4+ and some of the CD8+ clones produced variable amounts of IL-4. Unlike IFN-gamma, IL-4 production was not significantly different in clones generated in the presence or absence of IL-12. These data suggest that IL-12 primes the clone progenitors, inducing their differentiation to high IFN-gamma-producing clones. The suppression of IL-4-producing cells observed in polyclonally generated T cells in vivo and in vitro in the presence of IL-12 is not observed in this clonal model, suggesting that the suppression depends more on positive selection of non-IL-4-producing cells than on differentiation of individual clones. However, antigen-specific established Th2 clones that were unable to produce IFN-gamma with any other inducer did produce IFN-gamma at low but significant levels when stimulated with IL-12 in combination with specific antigen or insoluble anti-CD3 antibodies. This induction of IFN-gamma gene expression was transient, because culture of the established clones with IL-12 for up to 1 wk did not convert them into IFN-gamma producers when stimulated in the absence of IL-12. These results suggest that Th clones respond to IL-12 treatment either with a stable priming for IFN-gamma production or with only a transient low level expression of the IFN-gamma gene, depending on their stage of differentiation.


1990 ◽  
Vol 172 (4) ◽  
pp. 1065-1070 ◽  
Author(s):  
Y Kawabe ◽  
A Ochi

The cellular basis of the in vitro and in vivo T cell responses to Staphylococcus enterotoxin B (SEB) has been investigated. The proliferation and cytotoxicity of V beta 8.1,2+,CD4+ and CD8+ T cells were observed in in vitro response to SEB. In primary cytotoxicity assays, CD4+ T cells from control spleens were more active than their CD8+ counterparts, however, in cells derived from SEB-primed mice, CD8+ T cells were dominant in SEB-specific cytotoxicity. In vivo priming with SEB abrogated the response of V beta 8.1,2+,CD4+ T cells despite the fact that these cells exist in significant number. This SEB-specific anergy occurred only in V beta 8.1,2+,CD4+ T cells but not in CD8+ T cells. These findings indicate that the requirement for the induction of antigen-specific anergy is different between CD4+ and CD8+ T cells in post-thymic tolerance, and the existence of coanergic signals for the induction of T cell anergy is suggested.


1995 ◽  
Vol 182 (1) ◽  
pp. 5-13 ◽  
Author(s):  
P Stumbles ◽  
D Mason

In vitro experiments using purified rat CD4+ T cells in primary and secondary mixed leukocyte cultures (MLC) have been carried out to explore the mechanism of inhibition of cell-mediated autoimmune disease in the rat by a nondepleting monoclonal antibody (mAb) to CD4. Previous work has shown that W3/25, a mouse anti-rat CD4 mAb of immunoglobulin G1 isotype, completely prevents the development of the paralysis associated with experimental allergic encephalomyelitis (EAE) in Lewis rats, but does so without eliminating the encephalitogenic T cells. The in vitro experiments described in this study have shown that when CD4+ T cells were activated in the presence of the anti-CD4 mAb in a primary MLC, the synthesis of interferon (IFN) gamma, but not interleukin (IL) 2, was completely inhibited. After secondary stimulation, now in the absence of the mAb, the synthesis of IL-4 and IL-13 mRNA was greatly enhanced compared with that observed from CD4+ T cells derived from primary cultures in which the mAb was omitted. As IL-4 and IL-13 are known to antagonize cell-mediated immune reactions, and as EAE is cell-mediated disease, the data suggest that the W3/25 mAb controls EAE by modifying the cytokine repertoire of T cells that respond to the encephalitogen. The capacity for the mAb to suppress IFN-gamma synthesis provides, in part, an explanation for this change in cytokine production. These findings are discussed in terms of what is known of the factors that determine which cytokine genes are expressed on T cell activation. Possible implications for the evolution of T cell responses in human immunodeficiency virus infection are also discussed.


1997 ◽  
Vol 185 (12) ◽  
pp. 2133-2141 ◽  
Author(s):  
Elizabeth Ingulli ◽  
Anna Mondino ◽  
Alexander Khoruts ◽  
Marc K. Jenkins

Although lymphoid dendritic cells (DC) are thought to play an essential role in T cell activation, the initial physical interaction between antigen-bearing DC and antigen-specific T cells has never been directly observed in vivo under conditions where the specificity of the responding T cells for the relevant antigen could be unambiguously assessed. We used confocal microscopy to track the in vivo location of fluorescent dye-labeled DC and naive TCR transgenic CD4+ T cells specific for an OVA peptide–I-Ad complex after adoptive transfer into syngeneic recipients. DC that were not exposed to the OVA peptide, homed to the paracortical regions of the lymph nodes but did not interact with the OVA peptide-specific T cells. In contrast, the OVA peptide-specific T cells formed large clusters around paracortical DC that were pulsed in vitro with the OVA peptide before injection. Interactions were also observed between paracortical DC of the recipient and OVA peptide-specific T cells after administration of intact OVA. Injection of OVA peptide-pulsed DC caused the specific T cells to produce IL-2 in vivo, proliferate, and differentiate into effector cells capable of causing a delayed-type hypersensitivity reaction. Surprisingly, by 48 h after injection, OVA peptide-pulsed, but not unpulsed DC disappeared from the lymph nodes of mice that contained the transferred TCR transgenic population. These results demonstrate that antigen-bearing DC directly interact with naive antigen-specific T cells within the T cell–rich regions of lymph nodes. This interaction results in T cell activation and disappearance of the DC.


1989 ◽  
Vol 169 (6) ◽  
pp. 1993-2005 ◽  
Author(s):  
B D Jamieson ◽  
R Ahmed

This study documents that virus-specific CTL can persist indefinitely in vivo. This was accomplished by transferring Thy-1.1 T cells into Thy-1.2 recipient mice to specifically identify the donor T cell population and to characterize its antigenic specificity and function by using a virus-specific CTL assay. Thy-1.1+ T cells from mice previously immunized with lymphocytic choriomeningitis virus (LCMV) were transferred into Thy-1.2 mice persistently infected with LCMV. The transferred LCMV-specific CTL (Thy-1.1+ CD8+) eliminate virus from the chronically infected carriers and persist in the recipient mice in small numbers, comprising only a minor fraction of the total T cells. Upon re-exposure to virus, these long-lived "resting" CD8+ T cells proliferate in vivo to become the predominant cell population. These donor CD8+ T cells can be recovered up to a year post-transfer and still retain antigenic specificity and biological function. They kill LCMV infected H-2-matched cells in vitro and can eliminate virus upon transfer into a second infected host. In addition, these long-lived CD8+ T cells appear not to be dependent on help from CD4+ T cells, since depletion of CD4+ T cells has minimal or no effect on their biological properties (proliferation, CTL response, viral clearance). These donor CTL also exhibit an immunodominance over the host-derived LCMV-specific CTL response. When both host and donor T cells are present, the donor CTL response is dominant over the potential CTL response of the cured carrier host. Taken together, these results suggest that virus-specific CTL can persist for the life span of the host as memory cells.


2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S141-S141
Author(s):  
B Liu ◽  
M Spalinger ◽  
L G Perez ◽  
A Machicote ◽  
N Gagliani ◽  
...  

Abstract Background Inflammatory Bowel Disease (IBD) is characterized by an overwhelming gut inflammation, where CD4+ effector T cells are main mediators of the inflammatory response. Tofacitinib, a small molecular drug recently used in IBD patients, blocks the JAK/STAT signaling pathway necessary for CD4+ effector T-cell activation. However, clinical data show that a percentage of patients do not respond to the treatment. Our main goal is to identify biomarkers predicting the response of patients to tofacitinib. Methods Tofacitinib efficacy was studied in vivo in wild type (WT) and T-cell-specific PTPN2 deficient mice (CD4-Cre;Ptpn2 floxed) in which the JAK/STAT signaling pathway is over activated. WT and PTPN2 deficient mice were gavaged with tofacitinib (50mg/kg, twice daily) or vehicle. Acute DSS-colitis was induced. Colitis development was evaluated by weight loss, colonoscopy and histology. CD4+ T cells were isolated from the colon and analyzed by flow cytometry. To study the effect of tofacitinib on T-cell differentiation, we isolated naïve T cells from mouse spleen and polarized them in vitro to different T-cell subsets with or without tofacitinib. CD4+ T cells differentiation and cytokine production were analyzed by flow cytometry. To evaluate the influence of tofacitinib on human CD4+ T cells, human peripheral blood mononuclear cells (PBMCs) from healthy donors and IBD patients were stimulated in presence of tofacitinib, and analyzed by flow cytometry. Results While no protective effect was found after tofacitinib treatment in WT mice, PTPN2 deficient mice were protected from colitis based on less weight loss, lower endoscopic and histological scores. The expression of pro-inflammatory cytokines such as IL-17 and IFN-γ by colonic CD4+ T cells was also decreased by tofacitinib. Consistent with the in vivo observations, in vitro experiments revealed a strong impact of tofacitinib on CD4+ T-cells cytokine production. In PBMCs from IBD patients, IFN-γ and TNF-α expression was strongly impacted. In contrast, in healthy donors, IL-10 was the most impacted cytokine. Finally, tofacitinib decreased the in vitro differentiation of Th1, Th2, Th17, Th22, Treg and Tr1. Conclusion In the T-cell-specific PTPN2 deficient mice, tofacitinib exerts a protective effect after DSS-induced colitis. In line with the in vivo findings, in vitro experiments show that tofacitinib has a strong impact on pro-inflammatory cytokine production, especially in the IBD patients. Taken together, these data suggest that tofacitinib might be suitable primarily for IBD patients where the JAK/STAT signaling pathway is over activated.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 3077-3077
Author(s):  
Davis Yuri Torrejon ◽  
Jesse Meir Zaretsky ◽  
Daniel Sanghoon Shin ◽  
Mykola Onyshchenko ◽  
Gabriel Abril-Rodriguez ◽  
...  

3077 Background: We tested the biological significance of the loss of function (LOF) mutations in JAK1 or JAK2 within the IFN-receptor-pathway and in beta-2-microglobulin (B2M), which had been found in patient biopsies with resistance to anti-PD-1 therapy. Methods: We used CRISPR/Cas9 genome editing to generate JAK1, JAK2 and B2M knockout (KO) sublines of HLA-A*02:01 MART-1 or NY-ESO-1 positive human melanoma cell lines, tested using in-vitro T cell co-culture systems and in a syngeneic mouse model (MC38) to analyze the in-vivo antitumor activity with anti-PD1 therapy. Results: The JAK2-KO cell line was insensitive to IFN-gamma induced signaling and growth arrest (p < 0.001 compared with IFN-alpha or beta), while the JAK1-KO cell line was insensitive to all three IFNs. Baseline MHC class I expression after JAK1-KO was unaffected (baseline-MFI 1230 JAK1-KO vs 1570 parental, p = 0.66), but the magnitude of change was lower upon IFN-gamma exposure compared to the parental (MFI change with IFN-gamma, 26% decrease for JAK1-KO vs 50% increase for parental). There was no difference in in-vitro cytotoxicity by NY-ESO-1-TCR transgenic T-cells against JAK1-KO-NY-ESO-1+ melanoma cells compared to the parental (78% vs 82% cytotoxicity at 10:1 E:T ratio, p NS). However, B2M-KO was resistant to killing by MART-1 specific T-cells (2% vs 96% cytotoxicity at 10:1 E:T ratio, p < 0.0001). On the other hand, in the MC38 model the significant antitumor activity of anti-PD-1 against the wild type cells was lost in both JAK2-KO and B2M-KO. The percentage of CD8+ T cells has a trend of increase with anti-PD1 compared to untreated in the MC38 wild type (p = 0.1 d12), and a trend of decrease in MC38 B2M-KO (p = 0.2 d12), but no change in JAK2-KO tumors (p = 0.7 d12). Conclusions: JAK1/2 LOF mutations result in insensitivity to IFN induced antitumor effects, but does not impair T cell recognition and cytotoxicity, while B2M LOF results in lack of antigen presentation to T cells and loss of antitumor activity. However both lead to in-vivo resistance to anti-PD-1 therapy, suggesting they do so by independent mechanisms.


1992 ◽  
Vol 176 (4) ◽  
pp. 1091-1098 ◽  
Author(s):  
R A Seder ◽  
W E Paul ◽  
M M Davis ◽  
B Fazekas de St Groth

To study the factors that determine whether CD4+ T cells produce interleukin 4 (IL-4) or interferon gamma (IFN-gamma) upon stimulation we used a system allowing naive T cells to be primed in vitro by specific antigen. Dense CD4+ T cells were purified from mice that expressed transgenes encoding a T cell receptor specific for pigeon cytochrome C peptide 88-104 in association with I-Ek. These T cells produced very limited amounts of IL-4 and IFN-gamma upon immediate challenge with 88-104 and antigen-presenting cells (APC). However, after an initial "priming" culture in which they were incubated for 4 d in the presence of 88-104, APC, and 1,000 U/ml IL-4, the T cells acquired the capacity to produce substantial amounts of IL-4 upon rechallenge but made very little IFN-gamma. Cells primed in the absence of IL-4 produced IFN-gamma upon rechallenge but virtually no IL-4. The inhibitory effect of IL-4 on IFN-gamma production did not appear to be mediated by the induction of IL-10 production since IL-10 addition to initial cultures did not suppress priming for IFN-gamma production, nor did anti-IL-10 block the inhibitory effect of IL-4. IFN-gamma itself did not increase priming for IFN-gamma production, nor did anti-IFN-gamma reduce such priming. IFN-gamma did, however, diminish priming for IL-4 production when limiting amounts of IL-4 (100 U/ml) were used in the initial culture. The dominant effect of IL-4 in determining the lymphokine-producing phenotype of primed cells was observed with dendritic cells (DC), activated B cells, and I-Ek-transfected fibroblasts as APC. However, the different APC did vary in their potency, with DC being superior to activated B cells, which were superior to transfected fibroblasts.


Sign in / Sign up

Export Citation Format

Share Document