Mouse monoclonal antibody detects a new polymorphic Ia determinant other than HLA‐DR antigen: a possible allele of DC‐1

Abstract

Using a hybridoma technique, a monoclonal antibody (TA10) reactive with a new polymorphic B-cell antigen was obtained. The TA10 antibody reacted with 12 (24%) of B cells from 50 healthy individuals, but not with T cells. In contrast with the HLA-DR antigen, the TA10 antigen was preferentially detected on B cells, but not on monocytes. The reactive pattern of TA10 was closely associated with DR5 and its related DR antigen NJ2, and also found with DR4 or DRw9. The linkages of TA10 to these DR antigens were confirmed in the family study, indicating that the TA10 antigen is controlled by a closely linked but distinct locus from HLA-DR. Furthermore, two-dimensional gel analysis demonstrated that the TA10 determinant was expressed on a class II molecule whose heavy and light chains were different from those carrying the DR determinant. Thus, this monoclonal antibody might detect an allele of DC-1 which is found in association with DR5 and DRw6.2.