HUMAN MONOCLONAL ANTI-D SECRETING HETEROHYBRIDOMAS FROM PERIPHERAL B-LYMPHOCYTES EXPANDED IN THE CD40 SYSTEM

Peripheral human B lymphocytes isolated from four immunised anti-D don ors have been cultured in the CD40 system (Banchereau et al., 1991), p rior to fusion to murine X63Ag8.653 plasmacytoma cells. High fusion ef ficiency was noted in all cases and immunoglobulin (IgG and IgM) was d etected in nearly all heterohybrid containing wells. Only fusions usin g boosted donor lymphocytes generated specific anti-D secreting hybrid s. A short period of culture of committed B cell precursors in the CD4 0 system before fusion appears to be both adequate and efficient in pe rmitting generation of specific antibody-secreting hybrids.