Transmissible gastroenteritis virus antibody production in vitro by porcine peripheral blood leukocytes

The purpose of this study was to demonstrate the in vitro production of transmissible gastroenteritis virus (TGEV)-specific antibodies by peripheral blood leukocytes (PBL) harvested from piglets infected with TGEV. Piglets were infected with the virulent Purdue strain of TGEV and at intervals postinfection their PBL were cultivated in the presence of TGEV antigen, control antigen or pokeweed mitogen (PWM). The culture supernatants were tested for TGEV antibodies by a fixed cell enzyme immunoassay. Antibodies were never found in the supernatants of unprimed PBL cultures from control piglets, nor in cultures stimulated with control antigen, and antibodies were produced more frequently in response to stimulation of primed PBL with viral antigen than with PWM. In PBL cultures stimulated with viral antigen, TGEV antibodies of the IgG class were produced more frequently than IgA class antibodies. Optimal antibody responses were produced by PBL harvested two weeks after infection and cultivated at a concentration of 10(7) cells/mL for five days.