Peptide mimicry of carbohydrate epitopes on human immunodeficiency virus

Cancer-related, mucin-type carbohydrate epitopes, principally mannose and sialo-syl residues, are expressed on the envelope protein gp160 of the human immunodeficiency virus (HIV), Anticarbohydrate antibodies directed toward these and other carbohydrate epitopes are known to neutralize HIV-1 infection by cell-free virus, Carbohydrates, however, being T cell-independent antigens, typically elicit diminished immune responses. To overcome this potential draw back, we have examined the ability of peptides that mimic such epitopes to elicit immune responses that cross-react with carbohydrate structures, We report that mouse polyclonal antisera generated against peptides that mimic mucin-related carbohydrate epitopes have anti-HIV-1 activity. Generation of antibodies was not Ir-gene restricted, as at least two different strains of mice, Balb/c (H-2(d)) and C57BI/6 (H-2(b)), responded equally to the peptides, The antipeptide sera displayed neutralizing activity against HIV-I/MN and HIV-I/3B viral strains, This neutralization was as good as human anti-HIV sera. These results indicate that peptide mimics of carbohydrates provide a novel strategy for the further development of reagents that elicit immune responses to carbohydrate epitopes associated with many infectious organisms and tumor cells.