Surfactant protein A binds to the fusion glycoprotein of respiratory syncytial virus and neutralizes virion infectivity.
Collectins are a family of calcium-dependent collagenous lectins that appear to be important in innate host defense. We investigated the ability of three human collectins, namely, lung surfactant proteins A (SP-A) and D (SP-D) and the serum mannose-binding protein (MBP), to bind to the surface glycoproteins of respiratory syncytial virus (RSV). SP-A was shown to bind to the F (fusion) glycoprotein but not to the viral G (attachment) glycoprotein, and binding was completely abrogated in the presence of EDTA. Neither SP-D nor MBP bound to either glycoprotein. SP-A also neutralized RSV in a calcium dependent fashion. These results support a role for SP-A in the defense of infants against infection with RSV and indicate a possible mechanism for its protective activity.
Ghildyal
R
R
Department of Microbiology, University of Melbourne, Parkville, Victoria, Australia.
Hartley
C
C
Varrasso
A
A
Meanger
J
J
Voelker
D R
DR
Anders
E M
EM
Mills
J
J
D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D037222:Collectins; D006023:Glycoproteins / Q000378:metabolism; D015707:HN Protein; D006801:Humans; D009500:Neutralization Tests; D011510:Proteolipids / Q000378:metabolism*; D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000378:metabolism*; D011817:Rabbits; D012136:Respiratory Syncytial Viruses / Q000378:metabolism* / Q000502:physiology; D014407:Tumor Cells, Cultured; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000378:metabolism*
D002352:Carrier Proteins; D037222:Collectins; D006023:Glycoproteins; D015707:HN Protein; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C116204:attachment protein G