Abstract
The influence of macrolide antibiotics, josamycin (JS), roxithromycin (RXM) and azithromycin (AZ), on co-stimulatory molecule expression was examined using an in vitro cell culture technique. Spleen cells obtained from BALB/c mice 10 days after immunization with 8.0μg/ml of keyhole limpet haemocyanin (KLH) were cultured in the presence of 100.0μg/ ml of KLH and various concentrations of antibiotics for 72 hours. RXM and AZ, but not JS, inhibited cell activation induced by antigenic stimulation when the cells were cultured in the presence of more than 5.0 μg/ml of agents. Addition of RXM and AZ to cell cultures did not cause suppression of the proliferative response of spleen cells to anti-CD3 monoclonal antibody stimulation even when the cells were cultured in the presence of 10.0μg/ml of agents. The influence of these macrolide antibiotics on co-stimulatory molecule expression on spleen cells in response to antigenic stimulation was examined. Addition of RXM and AZ, but not JS, at a concentration of 5.0μg/ml into cultures markedly suppressed expression of the co-stimulatory molecules, CD40, CD80 and CD86, which are enhanced by antigenic stimulation in vitro.
