A cytotoxic monoclonal antibody specific for the private alloantigenic determinant of the HLA-B 13 molecule.

A murine monoclonal antibody (TU 110) prepared against blast cells of a patient with acute "undifferentiated" leukemia was tested in the microcytotoxicity assay on peripheral blood lymphocytes of 122 normal Caucasian donors. The TU 110 reactivity was found to show a correlation coefficient of 1.0 in population analysis for the presence of the HLA-B locus specificity B 13 as defined by alloantisera. Family segregation studies confirmed MHC linked inheritance of the TU 110 antigenic determinant strictly on HLA-B 13 positive haplotypes. As the first monoclonal reagent against the private specificity of this HLA-B locus antigen, TU 110 provides the possibility to study the structural relationships of sub- and supertypic determinants on this allotype and may help to correlate antigenic domains of HLA-B 13 with definable functional properties.