title: Suppressive effect of nonviable Mycoplasma hyopneumoniae on phytohemagglutinin-induced transformation of swine lymphocytes.
abstract: The effect of nonviable Mycoplasma hyopneumoniae on transformation of swine peripheral blood lymphocytes by mitogen was investigated. Lymphocyte transformation was evaluated as incorporation of [3H]-thymidine, using a microculture system. Mycoplasma hyopneumoniae was grown in Friis medium, inactivated with sodium azide, and washed with phosphate-buffered saline solution. Four strains of M hyopneumoniae, strain J, strain 11, and 2 low-passage isolates (1361A, 1375C), were found to suppress phytohemagglutinin-induced lymphocyte transformation. Mycoplasma hyopneumoniae strains J, 11, and 1361A reduced lymphocyte transformation by about 50%, whereas strain 1375C reduced lymphocyte transformation by 98.7%. The suppressive effect was abrogated by heating M hyopneumoniae at 60 C or at higher temperatures for 30 minutes. Sonication of the heated M hyopneumoniae cells partially restored the suppressive effect.
mesh_terms: D000818:Animals; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000187:drug effects*; D009174:Mycoplasma / Q000276:immunology*; D010835:Phytohemagglutinins / Q000494:pharmacology*; D013552:Swine / Q000276:immunology*
chemical_list: D010835:Phytohemagglutinins