scholarly journals The selective ablation of interleukin 2-producing cells isolated from transgenic mice.

1993 ◽  
Vol 177 (5) ◽  
pp. 1451-1459 ◽  
Author(s):  
L E Minasi ◽  
Y Kamogawa ◽  
S Carding ◽  
K Bottomly ◽  
R A Flavell

To better understand the requirement for interleukin 2 (IL-2) in specific immune responses, we have established the use of cell ablation to selectively eliminate T cells that produce IL-2. To accomplish this we have generated transgenic mice that express the herpes simplex virus 1-thymidine kinase (HSV-TK) gene under the transcriptional control of the murine IL-2 promoter that renders IL-2-producing cells sensitive to the cytotoxic effects of the antiviral drug ganciclovir (GANC). HSV-TK activity was specifically expressed in activated T cells from transgenic mice. When CD4 T cells from transgenic mice were stimulated with the superantigen staphylococcal enterotoxin A (SEA) in the presence of GANC, proliferation and IL-2 production were almost completely inhibited and the activated CD4+V beta 3+ T cell population, eliminated. Proliferation was not restored by adding IL-2, showing that most proliferating cells are not bystander cells. In contrast, the proliferative response to concanavalin A (Con A) was only partially inhibited by treatment of CD4 T cells with GANC, although the efficiency of eliminating IL-2-producing cells was shown to be comparable with that achieved using SEA. This suggests that a portion of the proliferative response to Con A occurs via an alternative pathway not requiring IL-2 synthesis and release.

Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 279-284 ◽  
Author(s):  
O Ayanlar-Batuman ◽  
E Ebert ◽  
SP Hauptman

Abstract The present studies were designed to investigate the mechanism(s) of the defective T cell proliferative response to various stimuli in patients with B cell chronic lymphocytic leukemia B-CLL. In 14 patients with advanced B-CLL (stage III or IV) we found the T cell response in the autologous (auto) and allogeneic (allo) mixed lymphocyte reaction (MLR) to be 35.7% and 30% of the controls, respectively. Proliferation in the MLR depends upon the production of and response to interleukin 2 (IL 2), a T cell growth factor. IL 2 production in eight B-CLL patients was 22% of the control. The response to IL 2 was measured by the increase in the T cell proliferation in the MLR with the addition of IL 2. T cell proliferation in both the auto and allo MLR of CLL patients was significantly lower than in the controls after the addition of IL 2. The proliferative response of normal T cells to stimulation by CLL B cells was 50% of the control. This latter response was increased to control levels when cultures were supplemented with exogenous IL 2, suggesting that CLL B cells could stimulate IL 2 receptor generation in normal T cells in an allo MLR, but not IL 2 production. The presence of IL 2 receptors on activated T cells was directly determined using anti- Tac, a monoclonal antibody with specificity for the IL 2 receptor. Of the mitogen- or MLR-activated T cells in CLL patients, 6% and 10%, respectively, expressed Tac antigen, whereas identically stimulated control T cells were 60% and 47% Tac+, respectively. Our findings suggest that T cells in B-CLL are defective in their recognition of self or foreign major histocompatibility antigens as demonstrated by their impaired responsiveness in the MLR. Thus, these cells are unable to produce IL 2 or generate IL 2 receptors.


Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 279-284 ◽  
Author(s):  
O Ayanlar-Batuman ◽  
E Ebert ◽  
SP Hauptman

The present studies were designed to investigate the mechanism(s) of the defective T cell proliferative response to various stimuli in patients with B cell chronic lymphocytic leukemia B-CLL. In 14 patients with advanced B-CLL (stage III or IV) we found the T cell response in the autologous (auto) and allogeneic (allo) mixed lymphocyte reaction (MLR) to be 35.7% and 30% of the controls, respectively. Proliferation in the MLR depends upon the production of and response to interleukin 2 (IL 2), a T cell growth factor. IL 2 production in eight B-CLL patients was 22% of the control. The response to IL 2 was measured by the increase in the T cell proliferation in the MLR with the addition of IL 2. T cell proliferation in both the auto and allo MLR of CLL patients was significantly lower than in the controls after the addition of IL 2. The proliferative response of normal T cells to stimulation by CLL B cells was 50% of the control. This latter response was increased to control levels when cultures were supplemented with exogenous IL 2, suggesting that CLL B cells could stimulate IL 2 receptor generation in normal T cells in an allo MLR, but not IL 2 production. The presence of IL 2 receptors on activated T cells was directly determined using anti- Tac, a monoclonal antibody with specificity for the IL 2 receptor. Of the mitogen- or MLR-activated T cells in CLL patients, 6% and 10%, respectively, expressed Tac antigen, whereas identically stimulated control T cells were 60% and 47% Tac+, respectively. Our findings suggest that T cells in B-CLL are defective in their recognition of self or foreign major histocompatibility antigens as demonstrated by their impaired responsiveness in the MLR. Thus, these cells are unable to produce IL 2 or generate IL 2 receptors.


Blood ◽  
2009 ◽  
Vol 113 (26) ◽  
pp. 6648-6657 ◽  
Author(s):  
R. Patrick Weitzel ◽  
Mathew L. Lesniewski ◽  
Peter Haviernik ◽  
Suzanne Kadereit ◽  
Patrick Leahy ◽  
...  

Abstract The reduced expression of nuclear factor of activated T cells-1 (NFAT1) protein in umbilical cord blood (UCB)–derived CD4+ T cells and the corresponding reduction in inflammatory cytokine secretion after stimulation in part underlies their phenotypic differences from adult blood (AB) CD4+ T cells. This muted response may contribute to the lower incidence and severity of high-grade acute graft-versus-host disease (aGVHD) exhibited by UCB grafts. Here we provide evidence that a specific microRNA, miR-184, inhibits NFAT1 protein expression elicited by UCB CD4+ T cells. Endogenous expression of miR-184 in UCB is 58.4-fold higher compared with AB CD4+ T cells, and miR-184 blocks production of NFAT1 protein through its complementary target sequence on the NFATc2 mRNA without transcript degradation. Furthermore, its negative effects on NFAT1 protein and downstream interleukin-2 (IL-2) transcription are reversed through antisense blocking in UCB and can be replicated via exogenous transfection of precursor miR-184 into AB CD4+ T cells. Our findings reveal a previously uncharacterized role for miR-184 in UCB CD4+ T cells and a novel function for microRNA in the early adaptive immune response.


Blood ◽  
1994 ◽  
Vol 84 (12) ◽  
pp. 4333-4343 ◽  
Author(s):  
DW Hunt ◽  
HI Huppertz ◽  
HJ Jiang ◽  
RE Petty

We have isolated low-density, nonadherent, nonphagocytic, HLA-DR+ve cells with the morphology of dendritic cells (DCs) from the cord blood of full-term newborn infants. Relative to adult DCs, cord blood DCs were poor stimulators of the mixed leukocyte reaction when either adult or cord blood mononuclear cells (MNCs) or T lymphocytes were used as responder cells. In contrast, cord blood T cells and MNCs responded normally to allogeneic adult DCs. Cord blood DCs performed poorly as accessory cells for T-lymphocyte mitogenic responses at suboptimal concentrations of concanavalin A (Con A) and phytohemagglutinin A or at optimal concentrations of mitogen and low numbers of DCs. Addition of recombinant interleukin-2 (rIL-2) or recombinant interferon-gamma (rIFN- gamma) to cord blood DC-T-cell cultures containing a suboptimal concentration of Con A potentiated the proliferative response. In contrast, rIL-2 and rIFN-gamma exerted little effect on the proliferative response of adult T cells cultured with Con A and DCs. Flow cytometric studies showed that levels of intercellular adhesion molecule-1 (ICAM-1; CD54) and major histocompatibility complex (MHC) class I HLA-ABC and class II HLA-DR antigens on cord blood DCs were significantly lower than those on adult blood DCs. These findings suggest that the relative inefficiency of cord blood DCs in the activation of T cells may be related to their low cell surface expression of MHC and cell adhesion molecules. The demonstrated impairment of cord blood DC function could be of importance in understanding the immunologic relationship between the fetus and mother and could contribute to the susceptibility of newborns to infection.


Blood ◽  
2001 ◽  
Vol 97 (8) ◽  
pp. 2205-2212 ◽  
Author(s):  
Chantal Cerdan ◽  
Elisabeth Devilard ◽  
Luc Xerri ◽  
Daniel Olive

Abstract Clonal expansion of activated T cells is controlled by homeostatic mechanisms leading to cell death of a large proportion of the cells. The CD3/TcR pathway induces cell death, mostly when triggered in the absence of costimulatory signal. The unique T cell–specific chemokine of the C class, lymphotactin (Lptn), has recently been shown to inhibit the production of Th1-type lymphokines in human CD4+ T cells. The present study shows the ability of Lptn to costimulate the death of CD4+ T lymphocytes triggered through CD3/TCR. The Lptn-mediated increased cell death exhibited characteristic features of apoptosis, as mainly determined by DNA fragmentation and exposure of an apoptotic-specific mitochondrial antigen. This apoptosis was dependent on Fas/FasL signaling, was not rescued by addition of interleukin 2, and proceeded with a predominant processing of both initiator procaspase-9 and effector procaspase-7. These caspase activities were further evidenced by specific cleavage of poly(ADP-ribose) polymerase (PARP) and CD3/TCR ζ-chain, but not DNA fragmentation factor (DFF45). This study demonstrates that the functional repertoire of Lptn in the regulation of human CD4+ T-lymphocyte activation includes the ability to costimulate apoptosis.


2000 ◽  
Vol 20 (2) ◽  
pp. 702-712 ◽  
Author(s):  
Chi-Wing Chow ◽  
Roger J. Davis

ABSTRACT Calcium-stimulated nuclear factor of activated T cells (NFAT) transcription activity at the interleukin-2 promoter is negatively regulated by cyclic AMP (cAMP). This effect of cAMP is mediated, in part, by protein kinase A phosphorylation of NFAT. The mechanism of regulation involves the creation of a phosphorylation-dependent binding site for 14-3-3. Decreased NFAT phosphorylation caused by the calcium-stimulated phosphatase calcineurin, or mutation of the PKA phosphorylation sites, disrupted 14-3-3 binding and increased NFAT transcription activity. In contrast, NFAT phosphorylation caused by cAMP increased 14-3-3 binding and reduced NFAT transcription activity. The regulated interaction between NFAT and 14-3-3 provides a mechanism for the integration of calcium and cAMP signaling pathways.


1998 ◽  
Vol 186 (2) ◽  
pp. 103-110 ◽  
Author(s):  
Yan-Wen Zhou ◽  
Yoshihiro Komada ◽  
Hiroto Inaba ◽  
Eiichi Azuma ◽  
Minoru Sakurai

2002 ◽  
Vol 196 (4) ◽  
pp. 481-492 ◽  
Author(s):  
Kristin V. Tarbell ◽  
Mark Lee ◽  
Erik Ranheim ◽  
Cheng Chi Chao ◽  
Maija Sanna ◽  
...  

Glutamic acid decarboxylase (GAD)65 is an early and important antigen in both human diabetes mellitus and the nonobese diabetic (NOD) mouse. However, the exact role of GAD65-specific T cells in diabetes pathogenesis is unclear. T cell responses to GAD65 occur early in diabetes pathogenesis, yet only one GAD65-specific T cell clone of many identified can transfer diabetes. We have generated transgenic mice on the NOD background expressing a T cell receptor (TCR)-specific for peptide epitope 286–300 (p286) of GAD65. These mice have GAD65-specific CD4+ T cells, as shown by staining with an I-Ag7(p286) tetramer reagent. Lymphocytes from these TCR transgenic mice proliferate and make interferon γ, interleukin (IL)-2, tumor necrosis factor (TNF)-α, and IL-10 when stimulated in vitro with GAD65 peptide 286–300, yet these TCR transgenic animals do not spontaneously develop diabetes, and insulitis is virtually undetectable. Furthermore, in vitro activated CD4 T cells from GAD 286 TCR transgenic mice express higher levels of CTL-associated antigen (CTLA)-4 than nontransgenic littermates. CD4+ T cells, or p286-tetramer+CD4+ Tcells, from GAD65 286–300-specific TCR transgenic mice delay diabetes induced in NOD.scid mice by diabetic NOD spleen cells. This data suggests that GAD65 peptide 286–300-specific T cells have disease protective capacity and are not pathogenic.


Sign in / Sign up

Export Citation Format

Share Document