Two new ELISAs using monoclonal H-Y antibody.

Biotin-conjugated monoclonal H-Y antibody was used to detect soluble H-Y antigen, directly, in two novel enzyme-based systems: a sandwich or 'capture' ELISA and an inhibition ELISA. In each case, soluble H-Y was readily detected in samples known to contain the antigen, provided that positive and negative samples were compared on an equivalent protein basis. By adding increasing concentrations of inhibitor (antigen) we define the useful range of the assays to be between 0.6 and 20.0 micrograms of added protein. Both sandwich and inhibition ELISAs gave similar results with antigens tested. The methods can accordingly be applied as direct diagnostics in the study of sex determination and in the assignment of gender.