Studies of Monoclonal Antibodies Specific for Major Histocompatibility Complex Products of the Rat

Sixteen monoclonal antibodies against antigens coded for by the RT1 complex of the rat have been produced. Fourteen are specific for the a haplotype: six recognize class II and eight class I antigens. Two are specific for the 1 haplotype, one reacting with class I and the other with class II antigens. By means of these monoclonal antibodies four independent clusters of antigens for class I antigens of the a haplotype and three for class II antigens could be defined. The three antigenic sites of class II antigens reside on the same heterodimer. The monoclonals described here are characterized with regard to Ig class and subclass, pI, and complement-activating capacity.