No significant correlation between specific antibodies to mouse mammary tumour virus and human cancer.

To study the possible involvement of mouse mammary tumour virus (MMTV) related agent in human cancer we analysed 300 samples of human sera for the presence of antibodies to MMTV structural proteins. All sera were tested by immunoblotting to achieve high specificity. Out of 300 sera, 22 reacted with transframe protein p30, 16 with the ribonucleoprotein p14, six with the envelope glycoprotein gp52 and three with the major core protein p27. Reactivities to p30 and p14 were observed in sera from cancer patients and healthy controls; reactivities to p27 and gp52 predominated in sera of cancer patients. Sera frequently reacted with a 42 kDa protein which is a cellular contaminant of the virus.