Definition of Polymorphism Within DR2-Associated DQw1 Molecules

The anti-HLA class II monoclonal antibody NDS15.38, produced and characterized in our laboratory, was assigned a DR2 specificity on the basis that on the panel of cell lines tested, it reacted exclusively with DR2-typed cells (1). Additional data from competitive inhibition experiments and saturating binding assays demonstrated that NDS15.38 reacted with a subpopulation of the class II antigens detected by a monomorphic anti-DR, DQ, DP reagent NFK2. Two-dimensional gel profiles confirmed these findings, but in a previous analysis the NDS15.38 profile was thought to be distinct from the profile obtained with the anti-DQw1 antibody SDR1.2. (2). More recent studies, including the workshop analysis have shown that the antibody reacts with the DQw1 molecule on a subpopulation of DR2-typed cells.