Distinction of two CD3-monoclonal antibodies in respect to the effectivity to modulate the induction of IgM- and gamma-interferon synthesis.

Monoclonal antibodies which specifically bind to epitopes within the T3-antigen complex (CD3 mAb) are excellent tools to analyse mechanisms of T-cell activation and of the interactions between T-cells, B-cells, accessory cells and intermediating immunefactors. In the present study we could show, that the CD-3 mAbs BMA 030 and BMA 031 are highly effective in modulating immunereactions, similar to antibodies directed to the T4-antigen (CD4-mAb) or the T8-antigen (CD8-mAbs) respectively. The data substantiate that depending on the experimental system BMA 030 and BMA 031 are clearly distinctive in their efficacy to modulate immunereactions. For therapeutical use of CD-3-monoclonal antibodies in organ transplantation those clone-specific differences of mAbs with identical binding specificity might cause for crucial differences in clinical applicability.