Lymphoblastoid cells as stimulators in mixed lymphocyte reactions in medium with bovine serum albumin

Abstract

It is possible to substitute 0.5% bovine serum albumin (BSA) for human serum in mixed lymphocyte cultures with lymphoblastoid cells as stimulators. BSA supplemented cultures showed a peak proliferative response on day 5 in 3 of 4 individuals tested. Pretreatment of responders (but not stimulators) with 20% serum for 20 min prior to culture, significantly enhanced the response. The use of BSA-supplemented media eliminates a major source of variation from human lymphocyte cultures. This assay system is particularly suited for studying the effect of antibodies (such as viral or alloantibodies) on lymphocyte proliferation. Satisfactory levels of proliferation were obtained when B, but not T, lymphoblastoid cell lines (LCLs) were used as stimulators in mixed lymphocyte cultures. Use of LCLs with defined HLA specificities makes available large numbers of stimulating cells. Similarly, the proliferative responses of lymphocytes to various modified stimulators such as virus infected or hapten-conjugated cells can now be quantitated more reproducibly.