IDENTIFICATION OF SALIVARY PROTEINS INHIBITING HERPES-SIMPLEX VIRUS-1REPLICATION

Salivary proteins play an important role in the maintenance of the ora l ecology. Previous studies have indicated that human submandibular-su blingual and parotid salivas can selectively suppress the in vitro inf ectivity of herpes simplex virus 1. The purpose of this study was to i dentify the salivary components in human submandibular-sublingual sali va that modulate in vitro infectivity. Assessment of the interaction o f viral particles with salivary components was accomplished using an i n vitro solid-phase assay. These experiments revealed that herpes simp lex virus particles selectively interact with the members of the saliv ary proline-rich protein and cystatin families. Subsequent yield reduc tion assays demonstrated the ability of proline-rich proteins and sali vary cystatins to inhibit the viral replication, with basic proline-ri ch peptides being more effective. Subsequent assays suggest that basic proline-rich peptides reduced the virus titer by interfering with pen etration and/or cellular processing of virus within the target cell. C ollectively, these results further suggest that salivary proteins have an important role in the host defense mechanism against recurrent her pesvirus infection.