@article{ref1,
title="Control of differential CD4+ T lymphocyte behavior in vitro is dictated by the pattern of CD molecule involvement",
journal="Ciênc. cult. (Säo Paulo)",
year="1994",
author="Reis, George A. dos and Palomo, Luis F. and Lopes, Marcela F. and Gomes, Nitza A. and Lima, Célio Freire de and Peçanha, Lígia T.",
volume="46",
number="5/6",
pages="358-62",
abstract="T lymphocyte responses in vitro are not all-or-none choices to environmental stimulation, but follow at least three distinct patterns: full activation and expansion, anergy induction, and receptor-mediated suicide by apoptosis. In vitro model systems were devised to investigate the differential control of T cell responses by surface CD activation molecules, CD4+ T cells from T. cruzi-infected mice are severely impaired in their proliferative response to TCR stimulation. TCR stimulation leads to CD4+ T cell suicide by apoptosis, but CD3 stimulation is less efficient in this effect. Triggering of normal CD4 T cells through CD4 coincident with TCR activation, does not affect proliferative responses, but induces marked morphological changes in the T cells, which become adherent, form extended cytoplasmic projections, and acquire motile behavior. This response requires IL4 production, and can be markedly upregulated by exogenous IL4. Autoreactive CD4 T cell functioning can help syngeneic B cells to produce a TH2 pattern of immunoglobulin isotypes following stimulation by a thymus independent antigen. These results indicate that distinct patterns of functional behavior in vitro can be induced, depending both on the past experience of the T cell and on the exact array of stimulatory CD antigens engaged in the process of activation. The relevance of these constraints in generating variable behavior for immunoregulation is discussed.<p /><p>Language: en</p>",
language="en",
issn="0009-6725",
doi="",
url="http://dx.doi.org/"
}