Genetic difference in the proliferative response to T mitogens between Hi/PHA and Lo/PHA lymphocytes is independent of accessory cell function.

The role of the macrophage as accessory cell in the proliferative response of lymphocytes to phytohemagglutinin (PHA) was studied in two lines of mice genetically selected for high and low responsiveness to T mitogens. Adherent cell depletion of lymph node cells abrogated the low (Lo)/PHA response, but only partially inhibited the high (Hi)/PHA response. Addition of peritoneal cells provided either by Hi/PHA or by Lo/PHA mice equally restored Hi/PHA responsiveness but had only a slight reconstituting effect on the inhibited Lo/PHA response.

Selection of BW 5147 subclones devoid of non-specific suppressive activity for use in cell hybridization.

Culture supernatants of BW 5147 cells widely used for T-cell hybridization often manifest non-MHC-restricted, non-antigen-specific regulatory activities on the mixed lymphocyte reaction (MLR) of mouse cells. This report demonstrates that, whereas supernatants of BW 5147 cells grown at low concentrations (2 X 10(5)/ml) enhanced MLR, high cell concentration (2 X 10(6)/ml) supernatants markedly inhibited this reaction. BW 5147 cell-free extracts significantly inhibited MLR and in vitro antibody production (PFC), as well as the mitogenic response to lipopolysaccharide E.

Effects of T mitogens on in vivo antibody production to a T-dependent antigen in lines of mice genetically selected for high or low in vitro responsiveness to PHA.

The influence of genes which regulate the in vitro T-cell proliferative response to T mitogen upon in vivo antibody production to a T-dependent antigen was studied in two lines of mice genetically selected for a high or a low in vitro lymphocyte response to phytohaemagglutinin (PHA). Kinetics of agglutinin production to increasing doses of sheep erythrocytes was similar in the two lines, except for the titres of mercaptoethanol-resistant antibodies, which were slightly lower in the low-responder line. Treatment with mitogen prior to immunization modified the antibody response in the two lines differently.

Delayed hypersensitivity and migration inhibition in two lines of mice genetically selected for high or low responsiveness to phytohemagglutinin.

Delayed-type hypersensitivity (DTH) and cell migration inhibition (MI) were studied in two lines of mice genetically selected for the high (Hi/PHA) or low (Lo/PHA) in vitro response of their lymphoid cells to phytochemagglutinin (PHA). A rapid photoelectric procedure for reading cell migrations enabled the study of MI over a wide range (10 log) of antigen concentrations in vitro. Hi/PHA mice required immunization with a 10 times higher dose of ovalbumin (OVA) in Freund's complete adjuvant (FCA) than Lo/PHA mice for a comparable response in DTH (footpad swelling) and MI of their induced peritoneal exudate cells (PEC).

In vitro viability of lymphoid cells from lines of mice genetically selected for high or low responsiveness to phytohemagglutinin.

The kinetics of viability of lymph node and spleen cells of mice genetically selected for "high" or "low" in vitro lymphocyte responsiveness to PHA were studied in PHA or PPD-stimulated short-term cultures. Lo/PHA cells were found to be less viable than Hi/PHA cells in unstimulated control cultures. PHA improved the viability of Lo/PHA cells while inducing proliferation of Hi/PHA cells with the appearance of more and larger lymphoblasts in the latter.