Bystander memory CD8 T cell proliferation after anti-CD40/IL-2 treatment is independent of CD4 T cells

Abstract Infants infected with HIV have a more severe course of disease and persistently higher viral loads than HIV-infected adults. However, the underlying pathogenesis of this exacerbation remains obscure. Here we compared the rate of CD4+ and CD8+ T-cell proliferation in intestinal and systemic lymphoid tissues of neonatal and adult rhesus macaques, and of normal and age-matched simian immunodeficiency virus (SIV)–infected neonates. The results demonstrate infant primates have much greater rates of CD4+ T-cell proliferation than adult macaques, and that these proliferating, recently “activated” CD4+ T cells are infected in intestinal and other lymphoid tissues of neonates, resulting in selective depletion of proliferating CD4+ T cells in acute infection. This depletion is accompanied by a marked increase in CD8+ T-cell activation and production, particularly in the intestinal tract. The data indicate intestinal CD4+ T cells of infant primates have a markedly accelerated rate of proliferation and maturation resulting in more rapid and sustained production of optimal target cells (activated memory CD4+ T cells), which may explain the sustained “peak” viremia characteristic of pediatric HIV infection. Eventual failure of CD4+ T-cell turnover in intestinal tissues may indicate a poorer prognosis for HIV-infected infants.

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Mapping of the autophagosomal degradome identifies IL-7Rα as key cargo in proliferating CD4+ T-cells

10.1101/2021.12.08.471825 ◽

2021 ◽

Author(s):

Dingxi Zhou ◽

Mariana Borsa ◽

Daniel J. Puleston ◽

Susanne Zellner ◽

Jesusa Capera ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

Cd4 T Cells ◽

Surface Expression ◽

T Cell Proliferation ◽

Gamma Chain ◽

Direct Identification ◽

The Common ◽

First Time

CD4+ T cells orchestrate both humoral and cytotoxic immune responses. While it is known that CD4+ T cell proliferation relies on autophagy, direct identification of the autophagosomal cargo involved is still missing. Here, we created a transgenic mouse model, which, for the first time, enables us to directly map the proteinaceous content of autophagosomes in any primary cell by LC3 proximity labelling. IL-7Rα, a cytokine receptor mostly found in naive and memory T cells, was reproducibly detected in autophagosomes of activated CD4+ T cells. Consistently, CD4+ T cells lacking autophagy showed increased IL-7Rα surface expression, while no defect in internalisation was observed. Mechanistically, excessive surface IL-7Rα sequestrates the common gamma chain, impairing the IL-2R assembly and downstream signalling crucial for T cell proliferation. This study provides proof-of-principle that key autophagy substrates can be reliably identified with this model to help mechanistically unravel autophagy's contribution to healthy physiology and disease.

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TSLP and IL-7 use two different mechanisms to regulate human CD4+ T cell homeostasis

Journal of Experimental Medicine ◽

10.1084/jem.20090153 ◽

2009 ◽

Vol 206 (10) ◽

pp. 2111-2119 ◽

Cited By ~ 61

Author(s):

Ning Lu ◽

Yi-Hong Wang ◽

Yui-Hsi Wang ◽

Kazuhiko Arima ◽

Shino Hanabuchi ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

Cd4 T Cells ◽

Cd4 T Cell ◽

Th2 Cells ◽

T Cell Proliferation ◽

T Cell Homeostasis ◽

Cell Homeostasis ◽

Th2 Differentiation

Whether thymic stromal lymphopoietin (TSLP) directly induces potent human CD4+ T cell proliferation and Th2 differentiation is unknown. We report that resting and activated CD4+ T cells expressed high levels of IL-7 receptor a chain but very low levels of TSLP receptor (TSLPR) when compared with levels expressed in myeloid dendritic cells (mDCs). This was confirmed by immunohistology and flow cytometry analyses showing that only a subset of mDCs, with more activated phenotypes, expressed TSLPR in human tonsils in vivo. IL-7 induced strong STAT1, -3, and -5 activation and promoted the proliferation of naive CD4+ T cells in the presence of anti-CD3 and anti-CD28 monoclonal antibodies, whereas TSLP induced weak STAT5 activation, associated with marginally improved cell survival and proliferation, but failed to induce cell expansion and Th2 differentiation. The effect of TSLP on enhancing strong human T cell proliferation was observed only when sorted naive CD4+ T cells were cultured with mDCs at levels as low as 0.5%. TSLP could only induce naive CD4+ T cells to differentiate into Th2 cells in the presence of allogeneic mDCs. These results demonstrate that IL-7 and TSLP use different mechanisms to regulate human CD4+ T cell homeostasis.

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Allergen-Induced C5a/C5aR1 Axis Activation in Pulmonary CD11b+ cDCs Promotes Pulmonary Tolerance through Downregulation of CD40

Cells ◽

10.3390/cells9020300 ◽

2020 ◽

Vol 9 (2) ◽

pp. 300 ◽

Cited By ~ 4

Author(s):

Konstantina Antoniou ◽

Fanny Ender ◽

Tillman Vollbrandt ◽

Yves Laumonnier ◽

Franziska Rathmann ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cd4 T Cells ◽

Cell Activation ◽

T Cell Proliferation ◽

C5a Receptor ◽

The Impact

Activation of the C5/C5a/C5a receptor 1 (C5aR1) axis during allergen sensitization protects from maladaptive T cell activation. To explore the underlying regulatory mechanisms, we analyzed the impact of C5aR1 activation on pulmonary CD11b+ conventional dendritic cells (cDCs) in the context of house-dust-mite (HDM) exposure. BALB/c mice were intratracheally immunized with an HDM/ovalbumin (OVA) mixture. After 24 h, we detected two CD11b+ cDC populations that could be distinguished on the basis of C5aR1 expression. C5aR1− but not C5aR1+ cDCs strongly induced T cell proliferation of OVA-reactive transgenic CD4+ T cells after re-exposure to antigen in vitro. C5aR1− cDCs expressed higher levels of MHC-II and CD40 than their C5aR1+ counterparts, which correlated directly with a higher frequency of interactions with cognate CD4+ T cells. Priming of OVA-specific T cells by C5aR1+ cDCs could be markedly increased by in vitro blockade of C5aR1 and this was associated with increased CD40 expression. Simultaneous blockade of C5aR1 and CD40L on C5aR1+ cDCs decreased T cell proliferation. Finally, pulsing with OVA-induced C5 production and its cleavage into C5a by both populations of CD11b+ cDCs. Thus, we propose a model in which allergen-induced autocrine C5a generation and subsequent C5aR1 activation in pulmonary CD11b+ cDCs promotes tolerance towards aeroallergens through downregulation of CD40.

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Perforin Is Important For Both CD4+ and CD8+ T Cell-Mediated Graft-Versus-Tumor Effect But Plays Differential Roles In CD4+ and CD8+ T Cell Expansion After Allogeneic Transplantation

Blood ◽

10.1182/blood.v122.21.3255.3255 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3255-3255

Author(s):

Nicholas Leigh ◽

Guanglin Bian ◽

Wei Du ◽

George L. Chen ◽

Hong Liu ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Cell Expansion ◽

Cd8 T Cell ◽

Cd4 T Cell ◽

T Cell Proliferation ◽

T Cell Expansion ◽

Time Point

Abstract Graft versus tumor (GVT) effect is the desired and integral outcome for successful allogeneic bone marrow transplantation (allo-BMT) for cancer patients. This effect is dependent on T cell mediated recognition and elimination of residual host tumor cells present after allo-BMT. T cell killing is mediated primarily via three pathways: perforin/granzymes, Fas/FasL, and cytotoxic cytokines. Recent work from our lab has revealed a detrimental role for granzyme B (GzmB) in GVT effect due to its role in activation induced cell death (AICD) of CD8+ T cells. As a result, GzmB-/- CD8+ T cells exhibited higher expansion after allo-BMT and subsequently provided better tumor control. Our current study sought to determine the role of perforin (Prf1) in GVT effect mediated by both CD4+ and CD8+ T cells. Using the MHC-mismatched C57BL/6 (H-2b) to BALB/c (H-2d) allo-BMT model, we first confirmed previous findings that when transplanting CD8+ T cells along with T cell depleted (TCD) BM cells, donor CD8+ T cells require Prf1 to mediate GVT effect against allogeneic A20 lymphoma (Fig 1A, Prf1-/- (n=4) vs WT (n=4), *P<0.05). In addition, our data suggest that Prf1 is also required for CD4+ T cells to effectively mediate GVT effect against A20, as transplant with Prf1-/- CD4+CD25- T cells does not control tumor growth as well as WT controls (Fig 1B). Our previous work showed that GzmB deficiency allows for less AICD and subsequently more CD8+ T cell expansion. New data now show a similar effect for Prf1 in CD8+ T cell accumulation, as Prf1-/- CD8+ T cells outcompete WT CD8+ T cells (CD45.1+) when these two genotypes are mixed in equal numbers and transplanted into tumor bearing BALB/c mice (n=5/time point, *P=0.02 day 9)(Fig 1C). This competitive advantage was due to less AICD in the Prf1-/- CD8+ T cells. However, Prf1 appears to be required for efficient GVT activity, because the higher number of Prf1-/- CD8+ T cells are still less capable than WT counterparts in controlling tumor growth. We next tested the effect of Prf1 in AICD in CD4+CD25- T cells, and again co-transplanted WT CD45.1+ and Prf1-/- CD4+CD25- T cells into tumor bearing mice for a competition assay. Unexpectedly, WT CD4+CD25- T cells accumulate to significantly higher numbers when in direct competition with Prf1-/- CD4+CD25- T cells (n=4/time point, **,P<0.01)(Fig 1D). When we measured apoptotic cells with Annexin V staining, we found that WT CD4+CD25- T cells still had significantly more AICD (Prf1-/- 38.3 ± 4.2% vs. WT 48.1 ± 5.1%, P<0.01 on day 7 post-BMT; Prf1-/- 12.7 ± 1.0% vs. WT 18.1 ± 3.4%, P<0.03 on day 9 post-BMT). This result suggests that while Prf1 has an important role in AICD, it may also play a role in another feature of CD4+ T cell biology. We then explored the hypothesis that may Prf1 promote CD4+ T cell proliferation by evaluating Hoescht staining on day 9 post-BMT. Preliminary results suggest that Prf1 may enhance T cell proliferation, as Prf1-/- CD4+ T cells have less actively dividing cells at this time point. Therefore, Prf1 appears to have a surprising role after allo-BMT in sustaining T cell expansion for CD4+ T cells, but not for CD8+ T cells. Another factor influencing GVT effect may be T cell phenotype. Our previous work with CD8+ T cells suggests that more effector memory (CD62LLOWCD44HIGH) T cells accumulate in the absence of GzmB, and that GzmB-/- CD8+ T cells exhibited higher GVT activity than WT controls. We now found that while Prf1-/- CD4+ T cells also skewed towards the effector memory phenotype (CD62LLOWCD44HIGH), loss of Prf1 still reduced the ability of CD4+ T cells to control tumor growth in this model of allo-BMT. In summary, our results suggest that Prf1 plays an important role in GVT responses mediated not only by CD8+ T cells but also by CD4+ T cells, which were shown in previous literature to mainly utilize Fas ligand and cytokine systems to mediate GVT activity. In addition, Prf1 can cause AICD to both CD4+ and CD8+ T cells after allo-BMT. While Prf1-induced AICD reduces CD8+ T cell expansion, Prf1 appears to play a previously unrecognized role enhancing CD4+ T cell proliferation via an unidentified mechanism. Disclosures: No relevant conflicts of interest to declare.

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Myeloid Leukemias Directly Suppress T Cell Proliferation Through STAT3 and Arginase Pathways

Blood ◽

10.1182/blood.v122.21.3885.3885 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3885-3885 ◽

Cited By ~ 2

Author(s):

Samantha Miner ◽

Sawa Ito ◽

Kazushi Tanimoto ◽

Nancy F. Hensel ◽

Fariba Chinian ◽

...

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

Cell Lines ◽

Cd4 T Cells ◽

Myeloid Leukemia ◽

Leukemia Cell ◽

Suppressor Cells ◽

T Cell Proliferation ◽

Immune Editing

Abstract The immune-editing effect of myeloid leukemia has recently been reported in several studies. We previously demonstrated that the K562 leukemia-derived cell line suppresses T cell proliferation, which suggests that myeloid leukemia may function in a similar way to myeloid derived suppressor cells (MDSC). While the mechanism of suppression in leukemia is not fully understood, recent murine and human studies suggest that the STAT3 and arginase pathways play a key role in the immunosuppressive function of MDSC. We hypothesized that myeloid leukemia utilizes the MDSC STAT3 and arginase pathway to evade immune control, and block anti-leukemic immune responses. To evaluate the suppressive capacity of myeloid leukemia on T cell proliferation, we isolated CD34+ blasts and myeloid derived suppressor cells (MDSC: CD11b+CD14+) from blood of primary leukemia samples by FACS sorting (n=5). These cells were co-cultured with CFSE-labeled CD4+ T cells (n=9), previously isolated from healthy donor PBMCs using an automated cell separator (RoboSep). After stimulating with CD3/CD28 Dynabeads (Invitrogen, New York, USA) for 72 hours, proliferation was measured by CFSE dilution of the viable cell population. In three myeloid leukemias studied, CD4+ T cell proliferation was significantly suppressed in the presence of primary CD34 blasts and MDSC cells (p<0.001). Interestingly, CD34 blasts demonstrated a greater suppressive effect on T cells compared to MDSC cells for these samples (not statistically significant p=0.61). Next we repeated the proliferation assay using five leukemia cell lines: THP-1 and AML1 (derived from AML), K562 and CML1 (derived from CML), and the Daudi lymphoid-derived leukemia cell line. After staining with cell tracer dye and irradiating 100Gy, the cells were co-incubated with CFSE-labeled CD4+ T cells from healthy volunteers (n=6). We found that CD4+ T cell proliferation in the presence of the myeloid leukemia cell lines was significantly suppressed (mean proliferation 5.7±0.9% to 26.1±10.7%: p<0.0001 to 0.05) compared to lymphoid cell lines (mean proliferation 76.3±8.2%: p>0.05), consistent with the results obtained with the primary leukemia samples. To evaluate the impact of STAT3 and arginase on the immunosuppressive function of myeloid leukemia, the five cell lines were primed overnight with either arginase inhibitor (N(ω)-Hydroxy-nor-L-arginine; EMD Biosciences, Inc., California, USA) or two STAT3 inhibitors (STAT3 Inhibitor VI or Cucurbitacin I; EMD Millipore, Massachusetts, USA). Then, CD4+ T cells from healthy donors (n=3) were cultured with either (1) leukemia without any inhibitor (2) leukemia in the presence of inhibitor (3) leukemia primed with inhibitor. Priming leukemia with arginase inhibitor and STAT3 inhibitors almost completely abrogated their suppressive effect of T cell proliferation (p<0.001). We conclude that myeloid leukemia, like MDSC, directly immunosuppresses T cells, through STAT-3 and arginase. This finding may underlie the immune-editing of T cells by myeloid leukemia. Our results suggest that STAT3 inhibitors could be used to augment leukemia-targeted immunotherapy. Further investigation of T cell biology within the leukemia microenvironment is needed to further define immune editing mechanisms in myeloid leukemia. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures: No relevant conflicts of interest to declare.

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A novel model for antigen-dependent activation of normal human T cells. Transmembrane signaling by crosslinkage of the CD3/T cell receptor-alpha/beta complex with the cluster determinant 2 antigen.

Journal of Experimental Medicine ◽

10.1084/jem.171.6.1965 ◽

1990 ◽

Vol 171 (6) ◽

pp. 1965-1979 ◽

Cited By ~ 16

Author(s):

M Suthanthiran

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

T Cell Proliferation ◽

Transmembrane Signaling ◽

Receptor Alpha ◽

Human T Cells ◽

Normal Human

Transmembrane signaling of normal human T cells was explored with mAbs directed at TCR, CD2, CD4, CD5, or CD8 antigens and highly purified CD4+ T cells and CD8+ T cells. Our experiments explicitly show that: (a) crosslinkage of TCR with the CD2 antigen, and not independent crosslinking of TCR and of CD2 antigen or crosslinking of either protein with the CD4 or CD8 antigen induces significant proliferation independent of co-stimulatory signals (e.g., accessory cells, recombinant lymphokines, or tumor promoter), (b) F(ab')2 fragments of mAb directed at the TCR and F(ab')2 anti-CD2, crosslinked with F(ab')2 fragments of rabbit anti-mouse IgG, promote the proliferation of highly purified T cells, (c) a prompt and sustained increase in intracellular free Ca2+ concentration results from crosslinkage of TCR with the CD2 antigen, (d) T cell proliferation induced by this novel approach is curtailed by EGTA and by direct or competitive inhibitors of PKC, (e) crosslinkage of TCR with the CD2 antigen results in the transcriptional activation and translation of the gene for IL-2 and in the expression of IL-2 receptor alpha (CD25), (f) anti-CD25 mAbs inhibit T cell proliferation initiated by crosslinkage of TCR with the CD2 antigen, and recombinant IL-2 restores the proliferative response. Our first demonstration that crosslinkage of TCR with the CD2 antigen induces proliferation of normal human CD4+ T cells and CD8+ T cells, in addition to revealing a novel activation mechanism utilizable by the two major subsets of T cells, suggest that the CD2 antigen might be targeted for the regulation of antigen-specific T cell immunity (e.g., organ transplantation).

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Conventional CD4+ T cells present bacterial antigens to induce cytotoxic and memory CD8+ T cell responses

Nature Communications ◽

10.1038/s41467-017-01661-7 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 9

Author(s):

Aránzazu Cruz-Adalia ◽

Guillermo Ramirez-Santiago ◽

Jesús Osuna-Pérez ◽

Mónica Torres-Torresano ◽

Virgina Zorita ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd4 T Cells ◽

T Cell Responses ◽

Cd8 T Cell ◽

Cell Responses ◽

Bacterial Antigens ◽

Memory Cd8 T Cell

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Regulatory CD4+CD25+ T Cells Restrict Memory CD8+ T Cell Responses

Journal of Experimental Medicine ◽

10.1084/jem.20011347 ◽

2002 ◽

Vol 196 (12) ◽

pp. 1585-1592 ◽

Cited By ~ 157

Author(s):

Mischo Kursar ◽

Kerstin Bonhagen ◽

Joachim Fensterle ◽

Anne Köhler ◽

Robert Hurwitz ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd4 T Cells ◽

Secondary Infection ◽

T Cell Responses ◽

Cd8 T Cell ◽

T Cell Response ◽

Cell Responses ◽

Boost Immunization ◽

Memory Cd8 T Cell

CD4+ T cell help is important for the generation of CD8+ T cell responses. We used depleting anti-CD4 mAb to analyze the role of CD4+ T cells for memory CD8+ T cell responses after secondary infection of mice with the intracellular bacterium Listeria monocytogenes, or after boost immunization by specific peptide or DNA vaccination. Surprisingly, anti-CD4 mAb treatment during secondary CD8+ T cell responses markedly enlarged the population size of antigen-specific CD8+ T cells. After boost immunization with peptide or DNA, this effect was particularly profound, and antigen-specific CD8+ T cell populations were enlarged at least 10-fold. In terms of cytokine production and cytotoxicity, the enlarged CD8+ T cell population consisted of functional effector T cells. In depletion and transfer experiments, the suppressive function could be ascribed to CD4+CD25+ T cells. Our results demonstrate that CD4+ T cells control the CD8+ T cell response in two directions. Initially, they promote the generation of a CD8+ T cell responses and later they restrain the strength of the CD8+ T cell memory response. Down-modulation of CD8+ T cell responses during infection could prevent harmful consequences after eradication of the pathogen.

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