Activation of rat T lymphocytes by anti-CD2 monoclonal antibodies (original) (raw)
Cellular Immunology, 1987
Monoclonal antibody 3A35 (MA 3A35) has previously been shown to be an activation marker of macrophages and T lymphocytes. It immunoprecipitated from macrophages a 200-kDa molecule belonging to the T200 family and from T cells a 85kDa antigen. In the present work, the factors controlling the expression of the epitope identified by MA 3A35 on polyclonal activated T cells and T-cell clones, as well as the ability of 3A35 alone or together with complement to interfere with T-cell functions, were investigated. Corticoresistant thymocytes unreactive with MA 3A35 became fully reactive after 2 days of in vitro stimulation by PMA and IL-2 and the level of reactivity per cell declined to a low level thereafter, In helper and cytolytic T-cell clones, the expression ofthe epitope defined by MA 3A35 was also maximal soon after antigenic stimulation then declined. In helper-T-cell clones, the epitope remained detectable during the entire culture period, whereas in cytolytic clones its expression was markedly reduced at the end of the culture. The lineage of cytotoxic T lymphocytes (CTL) as studied in a bulk culture of spleen cells primed in vivo against a syngeneic tumor exhibited similar regulation by antigenic stimulation. The CTL precursors were resistant to lysis by MA 3A35 plus complement; after 3 days of culture with the stimulatory antigen, they became highly sensitive but their sensitivity then diminished and mature CTL were completely resistant. MA 3A35 plus complement also killed the activated T cells which responded to macrophage-presented antigens and were thought to be mainly Lyt-l+. Therefore, the epitope identified by MA 3A35 was expressed predominantly at an early stage of T-cell activation. At a late stage, it persisted almost exclusively on helper and Lyt-1' cells. In addition, MA 3A35 plus complement Iysed NK cells, AK cells, and their precursors present in normal spleen. In the absence ofcomplement, MA 3A35 had no detectable effect on T-cell functions. 0 1987 Academic PXSS, IX. ' This work was supported by the F&&ration Nationale des Centres de Lutte contre le Cancer.
Similarities in sequences and cellular expression between rat CD2 and CD4 antigens
Journal of Experimental Medicine, 1987
The MRC OX-34 mouse mAb was raised against rat T blasts and was found to label all T lymphocytes and most thymocytes but not B lymphocytes (1) . The OX-34 antigen had an apparent mol wt of 50,000 (1), and it seemed possible that it was the rat equivalent of human CD2 (T11) antigen (2-4). However, 0X-34 mAb labeled many more cells in rat spleen than could be accounted for by T lymphocytes (1), a property not described for human CD2 (2-4).
Immunology
We produced three murine monoclonal antibodies (mAb) directed against the human T-cell differentiation antigen CD2 (formerly T11) and analysed their epitope specificity by E-rosette inhibition, cross-blocking and proliferation-induction experiments. When added together, two mAb (both IgG1 kappa) were able to induce proliferation in peripheral blood T cells. This proliferation was found to be strictly dependent on the presence of monocytes. The polymorphism of Fc receptors (FcR) expressed on human monocytes for murine IgG1 antibodies, which is readily demonstrable in anti-CD3-induced T-cell activation, was not found in the anti-CD2-driven system. Moreover, mAb directed against the 40,000 MW FcRII were unable to inhibit proliferation induced by the mitogenic anti-CD2 combination. Still, F(ab')2 fragments of the mitogenic anti-CD2 antibody combination could not initiate T-cell mitogenesis, despite their ability to induce a rise in the free intracellular [Ca2+]. The contributions of...
A monoclonal antibody to human B lymphoblastoid cells activates human and murine T lymphocytes
Cellular immunology, 1989
A B lymphoblastoid cell line can provide a comitogenic, accessory signal for mitogen-treated T cells. In a study evaluating the antigenic determinant of such cells that mediate this effect, a monoclonal antibody (I57) was raised against the Daudi cell line. This antibody was found to interact with a 30-kDa protein on these cells and had agonistic properties. It enhanced the B lymphoblastoid accessory cell and interleukin 1 (IL-1)-dependent stimulation of PHA-treated murine thymocytes. The stimulatory effect of I57 on PHA-treated thymocytes was more pronounced at high, supraoptimal concentrations of the lectin. This was in contrast with the effect of IL-1 that failed to stimulate these cells treated with PHA at high concentrations. I57 also enhanced stimulation of thymocytes treated with IL-2 alone or with both PHA and IL-2. I57 exhibited by itself mitogenic activity for human T cells. These cells, treated with IL-2, were further stimulated by I57. I57 seems to be different from othe...
Expression and ontogeny of murine CD2
European Journal of Immunology, 1989
Expression and ontogeny of murine CD2* CD2 was first defined as the erythrocyte rosetting protein on the surface of human T cells. Recently, the rat and murine homologues have been identified by cDNA cloning. In this report we demonstrate that CD2 is expressed on the surface of most adult murine peripheral lymphocytes and thymocytes by indirect immunofluorescence using an anti-murine CD2 antiserum. The expression of CD2 on murine B cells was unexpected since in rat and human species it has been defined as a T cell-specific marker. Furthermore, CD2 appears very early on fetal thymocytes during development. The level of surface expression increases from day 13 of gestation to day 17, after which the surface density appears to reach a steady state. Thus, CD2 is expressed on day-13 thymocytes at the same stage that Thy-1, Pgpl and the TcRy/6/ CD3 complex have been shown to be expressed.
Cellular Immunology, 1990
The signal requirements for activation and proliferation of CD1+ thymocytes have been studied in order to define whether this immature cell population could function as mature T cells do. We found that CD1+ cells expressed high levels of CD25 antigen upon triggering with specific monoclonal antibodies (mAbs) (anti-CD3, anti-CD2, anti-CD28) in association with low doses of Phorbol-13-myristate-12-acetate (PMA). More interestingly, we described that in the presence of PMA CD1+ thymocytes proliferate upon stimulation with anti-CD28 mAb as well as with a pair of anti-CD2 mAbs, without the need of exogenous interleukin-2 (IL2), whereas they respond to anti-CD3 mAb only if exogenous IL2 was provided. Furthermore, CD1+ cells stimulated under optimal proliferative conditions, gave rise to cell populations capable of lysing natural killer (NK)-sensitive (K562) and NK-resistant (MEL 10, Daudi, EPA1) tumor target cells. These data strongly support the idea that CD1+ thymocytes, under appropriate stimulations, display some of the functional capabilities of mature T cells.
The Journal of Immunology
When stimulated for a few days with the mitogenic GT2 + T I 1 CD2 mAb pair and IL-2, resting T cells were induced to proliferate but the introduction into the cultures of a third CD2 mAb resulted in apoptotic cell death of 40 to 60% of the cells. The death signal was active on T cells entered the cell cycle without causing an apparent cell cycle block and without discriminating between the G, and S phases. Apoptosis was not prevented by cycloheximide or actinomycin D, indicating that the death program was already expressed in preactivated cells awaiting an appropriate signal. A series of Abs, directed at various cell surface molecules, were unable to trigger apoptosis (except CD3 mAb), whereas most of the CD2 mAb tested were active, provided the third CD2 mAb was recognizing an epitope different from GT2 and T I 1 ,. Mere aggregation of CD2 molecules did not seem to be the triggering signal of apoptosis, because cross-linking cell-bound GT2 + T I 1 with an Ab to mouse IgG had no effect, suggesting that a conformational change was imposed on CD2 molecules by the third CD2 mAb. Stimulation performed in the presence of IL-2 predisposed both CD45RO+ and CD45RAf T cells to apoptosis, whereas stimulation in the presence of IL-4 primed only CD45RA+ T cells to undergo this process. Monocytes and potent co-signals of the CD2 pathway were unable to prevent CD2-induced apoptosis. Thus, successive engagements of the CD2 molecule of mature T cells by two and three CD2 mAbs recognizing distinct epitopes can provide in short term cultures signals for proliferation and apoptosis, depending on the activation state of the cells. lournal of Immunology, 1994, 152: 4861, P rogrammed cell death by apoptosis is a suicide pathway that can be activated in a broad variety of eukaryotic cells at certain stages of ontogeny or differentiation (1). As far as T cells are concerned, death by apoptosis is a characteristic feature of immature CD4+CD8+TCRlo thymocytes either exposed to anti-CD3 Abs in thymic organ culture (2) or exposed to glucocorticoid (3) and irradiation (4). It has been shown that administration of a peptide Ag to mice expressing the cognate transgenic TCR results in rapid apoptosis of cortical thymocytes (5), and that immature thymocytes from mice
Cellular immunology, 1988
Two monoclonal antibodies (mAb) recognizing different CD2 epitopes each inhibited anti-CD3-induced proliferation and anti-CD3-induced increase in surface CD2 expression. The magnitude of inhibition by either anti-CD2 mAb was dependent upon which anti-CD3 mAb was used as the stimulus, being more pronounced when the anti-CD3 mAb 454 was used as the stimulus than when either anti-CD3 mAb 147 or 446 was the stimulus. The effects of neuraminidase-treated sheep erythrocytes (which bind to CD2) were also more pronounced on mAb 454-induced proliferation than on mAb 147- or 446-induced proliferation. Furthermore, the effects of preincubation with anti-CD2 mAb depended upon the responder status of the donor to IgG1 anti-CD3 mAb. Preincubation of high-responder cells with anti-CD2 mAb had little effect on subsequent IgG1 anti-CD3-induced proliferation. In contrast, preincubation of low-responder cells with anti-CD2 mAb usually augmented the otherwise small proliferative response to IgG1 anti-C...
Cellular Immunology, 1988
CD3+ WT3 I T cells were sorted from peripheral blood ofa normal healthy donor by a FACS IV and cloned by limiting dilution in the presence of a phorbol ester (tetradecanoyl phorbol acetate, TPA), calcium ionophore (ionomycin, IO), interleukin-2 (IL-2) allogeneic cells, and phytohemagghttinin (PHA). One of the derived clones, 290-2, was investigated in detail. 290-2 mediated strong natural killer (NK) but not lymphokine-activated killer (LAK) activity. It proliferated in the presence of IL-2 but not IL-4. It carried the surface phenotype CD3+ WT3 l-CD4"'e"k+ CD8-, CD16-, and Leu 19+. Expression of CD4 was heterogeneous within the clone, since two of three subclones were also CD4"eak+ but one was CD4-. NK activity was blocked by monoclonal antibody (moAb) to CD1 la (LFAl), but not by monoclonal antibody (moAb) to either CD3 or CD4. Northern blotting revealed T-cell receptor (TCR-7) but not (Y-or full-length P-chain mRNA. 290-2 proliferated autonomously when stimulated with a combination of TPA + IO, with PHA or CD3 moAb and autologous B-cell lines (B-LCL) (and this was inhibited by an anti-IL-2 receptor moAb), but not to allogeneic B-LCL or any of the other stimulating agents alone. Unexpectedly, the TPA + IO stimulus which resulted in maximal proliferative responses did not trigger interferon-y or granulocyte/macrophage colony-stimulating factor production, although both lymphokines were secreted in the presence of B-LCL + TPA + IO. Proliferative responses were not enhanced by the presence of B-LCL. Thus, activation signals sufficient for autocrine proliferative responses were insufficient for secretion of other lymphokines. Such clones will provide valuable reagents for investigating the biology of the TCR--y+ T cell. o 1988