REGULATION OF LYMPHOCYTE RESPONSES IN VITRO

Regulation of Lymphocyte Responses in Vitro

DNA synthesis of normal rat spleen cells in response to endotoxin increases markedly if adherent cells are first removed from the cell suspension. Addition of small numbers of purified macrophages to the cultures restores the response to a low level. T-deprived cells show these effects in very much lesser degree. Large numbers of macrophages completely suppress the response of both normal and T...

Regulation of lymphocyte responses in vitro: potentiation and inhibition of rat lymphocyte responses to antigen and mitogens by cytochalasin B.

Cytochalasin B, at concentration between 0.02 and 0.2 mug/ml, was slightly stimulatory to lymph-node cells from normal rats and greatly potentiated their response to phytohemagglutinin and low concentrations of concanavalin A (mitogens for thymus-derived lymphocytes); it also potentiated the response of thymocytes to phytohemagglutinin. The response of lymphnode cells to lipopolysaccharide endo...

Serum regulation of in vitro lymphocyte responses in early experimental syphilis.

Sera from rabbits with early experimental syphilis were tested for their effect on in vitro lymphocyte transformation responses to related specific antigens (sonicated T. pallidum), unrelated specific antigens (sheep erythrocytes), and the T cell mitogen, concanavalin A. Results were compared with responses in preinfection sera and in sera from sham-infected rabbits. Titration experiments in wh...

Abnormalities of in Vitro Lymphocyte Responses during Rubella Virus Infections

In vitro rubella virus infections of lymphocytes from normal adult humans impaired their responsiveness to phytohemagglutinin (PHA) stimulations; a situation which seemed analogous to the PHA unresponsiveness of peripheral lymphocytes from babies with the congenital rubella syndrome. Such in vitro viral infection of normal cells also decreased the synthesis of normal nucleic acids and structura...

Regulation of Lymphocyte Response in Vitro and in Vivo