scholarly journals The Cell Cycle Time of CD8+ T Cells Responding In Vivo Is Controlled by the Type of Antigenic Stimulus

PLoS ONE ◽  
2010 ◽  
Vol 5 (11) ◽  
pp. e15423 ◽  
Author(s):  
Heesik Yoon ◽  
Taeg S. Kim ◽  
Thomas J. Braciale
Keyword(s):  
Cell Cycle ◽  
T Cells ◽  
Cd8 T Cells ◽  
Cycle Time ◽  
Cell Cycle Time ◽  
Antigenic Stimulus

scholarly journals Memory CD8+ T cells exhibit increased antigen threshold requirements for recall proliferation

2014 ◽  
Vol 211 (2) ◽  
pp. 345-356 ◽  
Author(s):  
Erin R. Mehlhop-Williams ◽  
Michael J. Bevan
Keyword(s):  
Cell Cycle ◽  
T Cells ◽  
Cd8 T Cells ◽  
Memory T Cells ◽  
Protein Tyrosine Phosphatases ◽  
Central Memory ◽  
Naive T Cells ◽  
Memory Cd8 T Cells ◽  
Naïve T Cells

A hallmark of immunological memory is the ability of previously primed T cells to undergo rapid recall responses upon antigen reencounter. Classic work has suggested that memory T cells proliferate in response to lower doses of antigen than naive T cells and with reduced requirements for co-stimulation. In contrast to this premise, we observed that naive but not memory T cells proliferate in vivo in response to limited antigen presentation. To reconcile these observations, we tested the antigen threshold requirement for cell cycle entry in naive and central memory CD8+ T cells. Although both naive and memory T cells detect low dose antigen, only naive T cells activate cell cycle effectors. Direct comparison of TCR signaling on a single cell basis indicated that central memory T cells do not activate Zap70, induce cMyc expression, or degrade p27 in response to antigen levels that activate these functions in naive T cells. The reduced sensitivity of memory T cells may result from both decreased surface TCR expression and increased expression of protein tyrosine phosphatases as compared with naive T cells. Our data describe a novel aspect of memory T cell antigen threshold sensitivity that may critically regulate recall expansion.

Therapeutically Infused Redirected T Cells Targeting WT1 Successfully Inhibited Leukemia Stem Cells in Vivo

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4221-4221
Author(s):  
Hiroaki Asai ◽  
Hiroshi Fujiwara ◽  
Toshiki Ochi ◽  
Yukihiro Miyazaki ◽  
Fumihiro Ochi ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Leukemia Cells ◽  
High Dose ◽  
Bone Marrow Niche ◽  
Cell Cycle Status

Abstract Abstract 4221 Background & Purpose: Recent findings regarding leukemia stem cell (LSC) have emphasized the importance of suppression of LSC for the achievement of durable remission, the first requisite to establish cure of leukemia. For this subject, successful graft-vs.-leukemia (GvL) effect in allogeneic hematopoietic stem cell transplantation (allo-HSCT) against human leukemias has strongly illustrated the importance of anti-leukemia immunity. Additionally, WT1, one of well-known leukemia-associated antigens, has been obviously demonstrated to be expressed by LSCs in bone marrow niche (Saito Y et al, Sci Transl Med.2010). On the other hand, cell-cycle quiescence of LSCs in bone marrow niche is importantly implicated in their chemoresistance. Taking all above, in this study, we set out to answer questions whether therapeutically adopted T-cell immunity towards WT1 enabled to suppress LSC in vivo, and whether cell-cycle status of leukemia cells affected the sensitivity to cyotocidal activity mediated by WT1-specific cytotoxic T cells (CTLs). Methods: Approval for this study was obtained from the Institutional Review Board of Ehime University Hospital. Written informed consent was given by all patients, healthy volunteers in accordance with the Declaration of Helsinki. Peripheral CD8+ T cells obtained from AML or ALL patients in complete remission (CR) or healthy individuals were gene-modified to express HLA-A*2402-restricted and WT1235–243 nonamer -specific T-cell receptor (TCR) using our unique TCR-a/b gene expression vector carrying silencers for endogenous TCRs (WT1-siTCR vector) were generated as effector cells. Bone marrow CD34+ leukemia (L-BMCD34+) cells isolated using immunomagnetic beads from HLA-A*2402 positive or negative patients with AML or ALL were serially transplanted into NOD/scid/γcnull (NOG) mice as previously reported (Ochi T et al. Blood, 2011). 12 weeks later, engrafted leukemia cells in murine bone marrow were examined using a flowcytometry. In some experiments, after engrafted, first transplanted mice were treated with intraperitoneal administration of high dose (150mg/kg) of cytosine arabinoside (Ara-C). A week later, those mice received intravenous administration of gene-modified autologous CD8+ T cells to express WT1-specific TCR or non-gene-modified (NGM) ones in combination with intraperioneal administration of 500u of IL-2 every 2 days. A week after therapeutic T-cell infusion, bone marrow cells were harvested, and transplantation into second mice. 12 weeks later, engrafted human leukemia cells in murine bone marrow were assessed. Next, using a time-lapse photo assay and fluorescent ubiqutination-based cell-cycle indicator (Fucci)-labeled K562-A24 cells which are known to produce high amounts of WT1 mRNA and are positive for HLA-A*2402, we directly assessed the impact of cell-cycle status of leukemia cells on their sensitivity to redirected CTL towards WT1 in vitro. Results: Using isolated L-BMCD34+ cells, LSCs were detectable as leukemia initiating cell in serially transplanted NOG mice. High dose of Ara-C treatment alone was unable to eradicate LSCs. An experiment using samples from a patient with HLA-A*2402+ ALL revealed that intravenously infused gene-modified autologous peripheral CD8+ T cells in CR successfully reduced leukemia burden in bone marrow which were refractory to high dose of Ara-C. In serial transplantation experiments using samples from AML patients, therapeutic infusion of redirected CD8+ T cells to express WT1-specific TCR, but not NGM ones in nadir state successfully eradicated LSCs out of murine bone marrow. In vitro time-lapse photo assay directly illustrated that retargeted CD8+T cells towards WT1 killed fucci-labeled K562-A24 cells irrelevantly to cell-cycle status of target leukemia cells. Summary: In this study, when leukemia mass burden was reduced, therapeutically infused gene-modified CD8+ T cells targeting WT1 successfully enabled to inhibit LSCs in vivo. Furthermore cell-cycle status of leukemia cells which is importantly implicated in their chemoresistance in bone marrow niche, did not affect WT1-specific cytocidal activity mediated by genetically redirected CTLs at all. Although it is preliminary, our observation encourages us to actively introduce redirected T cell-based antileukemia adoptive immunotherapy, aiming at a cure of leukemias. Disclosures: No relevant conflicts of interest to declare.

Regulatory and Activated T Cells in Stem Cell Autografts Collected by Mobilization with High-Dose Cyclophosphamide and Granulocyte Colony Stimulating Factor.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 5216-5216
Author(s):  
Maud Condomines ◽  
Philippe Quittet ◽  
Zhao-Yang Lu ◽  
Laure Nadal ◽  
Pascal Latry ◽  
...  
Keyword(s):  
Cell Cycle ◽  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cell Function ◽  
Effector Memory ◽  
High Dose ◽  
Cell Recovery

Abstract High-dose chemotherapy (HDC) supported by autograft of hematopoietic progenitors (HP) is a standard therapy for patients with multiple myeloma (MM). High-dose cyclophosphamide (CTX) and G-CSF are widely used to collect HP. As the number of lymphocytes in the autograft is a powerful prognostic factor in patients with MM, our purpose was to study how CTX-G-CSF treatment affects the phenotype and function of T cells, in particular regulatory T cells (Treg), in 15 patients with MM. CTX induced severe T cell immunosuppression with a slow and partial T-cell recovery (a threefold decrease) at the time of HP collection. CTX-G-CSF treatment did not affect the percentages of central memory (CD45RA−, CCR7+), effector memory (CD45RA−, CCR7−), and late effector (CD45RA+, CCR7−) CD4 or CD8 T cells but a decrease of naïve CD4 cells (CD45RA+, CCR7+) was found. The percentages of CD25+ cells increased two- to threefold in CD4 or CD8 T cells, respectively. Post-CTX treatment CD4CD25+ cells included both activated CD4CD25low cells and CD4CD25high T cells. The latter were Treg because they expressed high level of FOXP3 and membrane CTLA-4 mRNA and protein and displayed functional suppressor function. In CTX-G-CSF leukaphereses from 15 patients with MM, the mean Treg number was one fifth that of CD34 and the CD3, CD4 and CD8 numbers respectively 3 fold, 2 fold and equal that of CD34. Post-CTX-G-CSF treatment CD3 cells did not cell cycle in vivo and died in short-term culture in vitro. Adding IL-2 or IL-15 induced their survival and cell cycle, and stimulation with anti-CD3 MoAb led to efficient growth in vitro. These results suggest that following CTX-G-CSF treatment, CD3 cells are preactivated in vivo and do not cell cycle, likely due to a lack of T cell growth factors in vivo. The current data indicate that CTX-G-CSF treatment profoundly affects T cell function without eliminating Treg. The persistence of Treg could be explained by an opposite effect of CTX known to kill Treg and of G-CSF amplifying Treg. Given the major impact of lymphocyte count on patients’ survival post HDC and HP and T cell graft, the present data invite to define novel therapeutic strategies to improve T cell recovery in vivo while limiting Treg expansion.

Anaphase and telophase labeling patterns following administration of3H-thymidine as an indicator of cell cycle time in vivo

1981 ◽  
Vol 36 (1) ◽  
pp. 123-131
Author(s):  
Hubert Läng ◽  
Nicolas Odartchenko ◽  
Hans Riedwyl ◽  
Max W. Hess ◽  
Hans Cottier
Keyword(s):  
Cell Cycle ◽  
Cycle Time ◽  
Cell Cycle Time

scholarly journals A reassessment of the role of B7-1 expression in tumor rejection.

1995 ◽  
Vol 182 (5) ◽  
pp. 1415-1421 ◽  
Author(s):  
T C Wu ◽  
A Y Huang ◽  
E M Jaffee ◽  
H I Levitsky ◽  
D M Pardoll
Keyword(s):  
T Cells ◽  
Tumor Cells ◽  
Cd8 T Cells ◽  
Tumor Rejection ◽  
Type B ◽  
Wild Type ◽  
Systemic Immunity ◽  
Murine Tumor

Introduction of the B7-1 gene into murine tumor cells can result in rejection of the B7-1 transductants and, in some cases, systemic immunity to subsequent challenge with the nontransduced tumor cells. These effects have been largely attributed to the function of B7-1 as a costimulator in directly activating tumor specific, major histocompatibility class I-restricted CD8+ T cells. We examined the role of B7-1 expression in the direct rejection as well as in the induction of systemic immunity to a nonimmunogenic murine tumor. B-16 melanoma cells with high levels of B7-1 expression did not grow in C57BL/6 recipient mice, while wild-type B-16 cells and cells with low B7-1 expression grew progressively within 21 d. In mixing experiments with B7-1hi and wild-type B-16 cells, tumors grew out in vivo even when a minority of cells were B7-1-. Furthermore, the occasional tumors that grew out after injection of 100% B-16 B7-1hi cells showed markedly decreased B7-1 expression. In vivo antibody depletions showed that NK1.1 and CD8+ T cells, but not CD4+ T cells, were essential for the in vivo rejection of tumors. Animals that rejected B-16 B7-1hi tumors did not develop enhanced systemic immunity against challenge with wild-type B-16 cells. These results suggest that a major role of B7-1 expression by tumors is to mediate direct recognition and killing by natural killer cells. With an intrinsically nonimmunogenic tumor, this direct killing does not lead to enhanced systemic immunity.

scholarly journals CD28 Costimulation Is Required for In Vivo Induction of Peripheral Tolerance in CD8 T Cells

2002 ◽  
Vol 197 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Melanie S. Vacchio ◽  
Richard J. Hodes
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Tolerance Induction ◽  
Peripheral Tolerance ◽  
Cd8 Cells ◽  
Costimulatory Signal ◽  
Cd28 Costimulation

Whereas ligation of CD28 is known to provide a critical costimulatory signal for activation of CD4 T cells, the requirement for CD28 as a costimulatory signal during activation of CD8 cells is less well defined. Even less is known about the involvement of CD28 signals during peripheral tolerance induction in CD8 T cells. In this study, comparison of T cell responses from CD28-deficient and CD28 wild-type H-Y–specific T cell receptor transgenic mice reveals that CD8 cells can proliferate, secrete cytokines, and generate cytotoxic T lymphocytes efficiently in the absence of CD28 costimulation in vitro. Surprisingly, using pregnancy as a model to study the H-Y–specific response of maternal T cells in the presence or absence of CD28 costimulation in vivo, it was found that peripheral tolerance does not occur in CD28KO pregnants in contrast to the partial clonal deletion and hyporesponsiveness of remaining T cells observed in CD28WT pregnants. These data demonstrate for the first time that CD28 is critical for tolerance induction of CD8 T cells, contrasting markedly with CD28 independence of in vitro activation, and suggest that the role of CD28/B7 interactions in peripheral tolerance of CD8 T cells may differ significantly from that of CD4 T cells.

scholarly journals DNAM-1 promotes activation of cytotoxic lymphocytes by nonprofessional antigen-presenting cells and tumors

2008 ◽  
Vol 205 (13) ◽  
pp. 2965-2973 ◽  
Author(s):  
Susan Gilfillan ◽  
Christopher J. Chan ◽  
Marina Cella ◽  
Nicole M. Haynes ◽  
Aaron S. Rapaport ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Nk Cells ◽  
Adhesion Molecules ◽  
Cd8 T Cells ◽  
Nk Cell ◽  
Cd8 T Cell ◽  
Antigen Presenting

Natural killer (NK) cells and CD8 T cells require adhesion molecules for migration, activation, expansion, differentiation, and effector functions. DNAX accessory molecule 1 (DNAM-1), an adhesion molecule belonging to the immunoglobulin superfamily, promotes many of these functions in vitro. However, because NK cells and CD8 T cells express multiple adhesion molecules, it is unclear whether DNAM-1 has a unique function or is effectively redundant in vivo. To address this question, we generated mice lacking DNAM-1 and evaluated DNAM-1–deficient CD8 T cell and NK cell function in vitro and in vivo. Our results demonstrate that CD8 T cells require DNAM-1 for co-stimulation when recognizing antigen presented by nonprofessional antigen-presenting cells; in contrast, DNAM-1 is dispensable when dendritic cells present the antigen. Similarly, NK cells require DNAM-1 for the elimination of tumor cells that are comparatively resistant to NK cell–mediated cytotoxicity caused by the paucity of other NK cell–activating ligands. We conclude that DNAM-1 serves to extend the range of target cells that can activate CD8 T cell and NK cells and, hence, may be essential for immunosurveillance against tumors and/or viruses that evade recognition by other activating or accessory molecules.

Sign in / Sign up

Export Citation Format

Share Document