The outcome of cell mediated lympholysis is influenced by the antibiotics in the culture medium.

Abstract

Recently we could demonstrate that antibiotics can interact with polymorphic membrane determinants. As a result, these determinants can no longer react with their corresponding antisera (Claas et al. 1981, 1982). In the present experiments it was found that allogeneic cytotoxic T cells (CTLs), which were cultured in the presence of antibiotics, induced significantly stronger lysis against the specific target than CTLs which were cultured in the absence of antibiotics. In some cases the CML assay was only positive according to the European Workshop criteria when penicillin was added to the cultures, whereas the assay was negative in the absence of penicillin. On the other hand when CTLs were induced in an MLC culture without penicillin, lysis was higher against the target cell in the absence of penicillin than in the presence of penicillin. By adding penicillin to the effector phase, inhibition of lysis was observed. No difference in 3H-thymidine-incorporation was observed between MLC cultures with and without antibiotics. We conclude that antibiotics in the culture medium can influence the outcome of CML experiments.