Induction of beta-2-microglobulin release in vitro by chronic lymphocytic leukaemia cells: relation to total protein synthesis

The in vitro production of beta(2)-M by B-CLL cells from 27 patients was investigated. In all cases, low spontaneous beta(2)-M release was observed. The production of beta(2)-M was enhanced to various extents when induced with 13 different stimulants and their combinations including IL-2, TNF alpha, SAC and TPA. beta(2)-M release was 3.8-fold (range from 1.9 to 9.2-fold) in cultures stimulated with TPA (10 ng/ml), compared with the spontaneous release, and even faster if TNF alpha or IL-2 were added. A strong correlation was revealed between beta(2)-M production and the total protein synthesis of leukaemic cells when the latter was assessed using C-14-L-leucine incorporation. Hence, both beta(2)-M release and leucine incorporation are promising activation markers for CLL B-lymphocytes. (C) 1999 Elsevier Science Ltd. All rights reserved.