DIFFERENTIAL LYMPHOKINE EXPRESSION BY RAT ANTIGEN-SPECIFIC CD4(-CELL LINES WITH ANTIGEN AND MITOGEN() T)

Retinal soluble antigen (S-Ag) and purified protein derivative (PPD)-s pecific T cell lines established from Lewis rats were used to study th e pattern of lymphokine expression to see if it varied with the induci ng stimulus. Lymphokine mRNA expression was detected by PCR combined w ith Southern analysis after 6-hr stimulation and protein secretion ass essed by bioassays at 24 hr poststimulation. S-Ag-specific T cell line s when stimulated with antigen expressed IL-2, IFN-gamma, and IL-4 mRN A, whereas only IL-2 and IFN-gamma could be detected in the supernatan ts. This is in contrast to the findings after stimulation of the PPD c ell lines with PPD where IL-4 could be detected in the supernatants. T he time course studies (3, 6, 24, 48, and 72 hr) with one of the S-Ag- specific T cell lines showed that S-Ag activation did not induce any d etectable IL-4 bioactivity. However, when the S-Ag T cell line was sti mulated by Con A or PMA, IL-4 was detected in the supernatants followi ng Con A activation, suggesting that the way in which the T cell is ac tivated has an effect on its resultant lymphokine secretion. (C) 1994 Academic Press, Inc.