Assuntos
Separação Celular/métodos , Linfócitos T/classificação , Animais , Células Produtoras de Anticorpos/classificação , Células Produtoras de Anticorpos/imunologia , Linfócitos B , Humanos , Ativação Linfocitária , Fagócitos , Mitógenos de Phytolacca americana/farmacologia , Receptores de Antígenos de Linfócitos B , Formação de Roseta , Ovinos , Proteína Estafilocócica A/farmacologia , Linfócitos T/imunologia , beta-Aminoetil Isotioureia/farmacologiaRESUMO
With age, NZB mice lose their ability to develop a cytotoxic response after alloimmunization in vitro. This decline is shown to coincide with a diminution of T-helper cell activity as assessed by proliferation in mixed lymphocyte culture or in response to PHA. When cytotoxic T cell precursors are activated with the polyclonal activator Con A, there is no reduction in the number of cytotoxic effector T cells that develop. No autoreactive cytotoxic cells are seen in Con A-activated cultures. These findings are related to previous work on cell-mediated immunity in NZB and B/W mice.
Assuntos
Envelhecimento , Células Matadoras Naturais/imunologia , Linfócitos T/imunologia , Animais , Concanavalina A/farmacologia , Citotoxicidade Imunológica , Epitopos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NZBRESUMO
We have studied the induction of cytoxic activity in murine T cells by the T cell mitogen Con A. Here we report the results of experiments that indicate that this cytotoxicity develops in the same class of T cells potentially activatable to cytotoxicity by immunization with allogeneic cells. Cytotoxic activity does not result from activation of cells of the T-helper class by PHA, and extensive reduction of the proportion of cells of the T-helper class by in vivo treatment with ATS does not comparably reduce the cytotoxicity developed in response to Con A. The Con A-activated cytotoxic cell sediments as a large cell. Furthermore, spleen cell populations previously immunized to alloantigens in vivo develop greatly increased cytotoxicity specific for the alloantigen of the immunizing haplotype after culture with Con A in vitro.