Cytomegalovirus proteins: II. Polypeptide composition of cytomegalovirus complement-fixing antigen

Complement-fixing (CF) antigen, prepared from cytomegalovirus (CMV)-infected cells and solubilized by urea and Tween-20, was fractionated on agarose gel columns. Its molecular weight was 1.5--5 X 10(7) daltons, and it contained 5 major peptides with molecular weights from 60,000--90,000 daltons. The peptide with a molecular weight of 70,000 daltons which was present in the solubilized CF antigen was absent in a soluble fraction from infected cells without CF activity and may be, therefore, important in this respect. The antigens present in the CF antigen did not elicit neutralizing antibody.