Antibodies to MuMTV proteins in the sera of mammary carcinoma patients' healthy daughters.

The presence of antibodies to MuMTV-related proteins in sera of 31 mammary carcinoma patients' healthy daughters have been tested by indirect immunoperoxidase method (ELISA). Ten of them (32.3 +/- 8.4%) reacted with MuMTV proteins preparations, but not with MuLV, RaLV, SSV, MPMV proteins or preparations of mouse embryonic tissues. The percent of positive sera in this group is almost ten times higher than among women without breast cancer in family history (earlier published data). By immunoblotting method the specificity for five positive sera was determined. Two sera react with p27, one with p27 and to a less extent with gp52, one-only with gp52 and one more serum with both proteins equally. Mothers of the daughters with positive-reacted sera were characterized by premenopausal tumors, detected on early (I, IIa) clinical stage of disease.