Stimulation of chicken lymphocytes by T- and B-cell mitogens

Abstract

Cultures of chicken spleen, peripheral blood, thymus, and bursal lymphocytes were tested for mitogenic stimulation by phytohaemagglutinin (PHA), concanavalin A (ConA), pokeweed mitogen (PWM), bacterial lipopolysaccharide (LPS), trypsin, and insulin. Spleen and blood leukocytes were stimulated by both the lectins and LPS, and also to some degree by trypsin and insulin as judged by increased incorporation of [ 3H]thymidine into acid-insoluble material. This was observed in cultures incubated in serum-free medium as well as in the presence of foetal bovine serum or autologous plasma. Thymus cells were reproducibly stimulated by high concentrations of PHA. No significant responses were obtained in bursal cell cultures with any of the compounds tested. Removal of cotton wool-adherent cells from the spleen cell suspensions resulted in a subpopulation of cells which were stimulated by PHA but showed little response to ConA, PWM, or LPS. This procedure did not remove surface immunoglobulin-bearing cells from the original suspension. Both these enriched spleen lymphocytes and the unfractionated spleen, blood and thymus leukocyte cultures were effectively stimulated by a partially purified PHA but with a highly purified PHA preparation only at very high concentrations. These and other results suggest that the mitogenic components in crude PHA preparations are different for chicken and human or mouse cells.