Biased utilization of immunoglobulin variable region heavy- and light-chain genes by the malignant CD5- B lymphocytes from patients with Burkitt's lymphoma.

Twenty-six established Burkitt's lymphoma (BL) cell lines from endemic or sporadic groups of patients were examined for the expression of cross-reactive idiotypes (CRI) associated with VHI, VHIII, VHIV, VHVI, VKIIIa and VKIIIb heavy- and light-chain gene products, using a panel of anti-CRI and anti-subgroup monoclonal antibodies (MAbs). Membrane, cytoplasmic and secreted immunoglobulins (Ig) were analysed by immunofluorescence, immunoperoxidase and ELISA respectively. While 35% of the lines expressed either of the VHIV-associated CRI, recognised by the MAbs 9G4 or LCI, none expressed the other VH-associated CRI included in our study. Of the kappa light chain expressing BL lines 54% and 46% belonged to the VKIII subgroup and VKIIIb sub-subgroups respectively. None, however, was found to express the VKIIIa or VKIIIb-associated CRI, recognised by the 6B6.6 and 17-109 MAbs. A significant association has been observed between the expression of the VHIV-associated CRI and the VKIII subgroup within the BL lines derived from the sporadic group of patients as compared with their endemic counterparts. Our results suggest that the expressed repertoire of Ig variable region genes within the malignant B lymphocytes of BL is not random and that a highly selective mechanism(s) may operate on this subset of B lymphocytes, as evidenced by the expression of the VH and VK gene products.