[Isolation of antibacterial polypeptides of human cervical mucus]

The acid-soluble extract of human cervical mucus was obtained by solving mucus with 5% acetic acid in the presence of protease inhibitor. The antibacterial activity of the acid-soluble extract was analyzed by gel overlay technique. The result showed that two protein bands which were designated human cervical protein-1 (Hcp-1), human cervical protein-2(Hcp-2) were potently antibacterial against E. coli 25922 and S. aureus 25923. Tricine-SDS-PAGE analysis indicated that Hcp-1, Hcp-2 actually contained three and four protein bands respectively. The molecular weights of Hcp-1 were 6.7 kd, 10 kd, 15.4 kd; these of Hcp-2 were 4.4 kd, 6.7 kd, 9 kd, 15.4 kd. Our studies suggested that human cervical mucosa might secrete some currently-unknown antibacterial polypeptides which play an important role in the cervical defense against infection.