Age-dependent resistance of human alveolar macrophages to herpes simplex virus.

Studies in mice demonstrate an age-dependent susceptibility to disseminated herpesvirus infection which is mediated. at least in part, by a defect in macrophage antiviral function. We examined the growth of herpes simplex virus within human alveolar macrophages obtained by bronchopulmonary lavage from neonates, adults with a variety of immunosuppressive disorders, and healthy adult volunteers. At 24 h postinfection, mean viral titers in neonatal macrophages increased 19-fold over adsorbed virus levels, a highly significant increase when compared to either immunosuppressed or normal adult macrophages (P less than 0.0005). These findings indicate that human macrophages, like those of mice, exhibit age-dependent permissiveness for the replication of herpes simplex virus. This permissiveness may at least partially account for the clinical observation that human newborns are highly susceptible to disseminated herpes simplex virus infections, whereas adults are not.