Influenza viruses differ in ability to infect macrophages and to induce a local inflammatory response following intraperitoneal injection of mice

Abstract

Strains of influenza A virus show marked differences in their ability to infect murine macrophages (Mφ) such that strain A/PR/8/34 (PR8; H1N1) infects M Mφ poorly while strain BJx109 (H3N2) infects M Mφ to high levels. Given the central role of M Mφ in initiating and regulating inflammatory responses, we hypothesized that virus strains that infect M Mφ poorly may also be poor at initiating inflammatory responses. Studies to compare the inflammatory response of mice after intranasal inoculation with either BJx109 or PR8 were confounded by the rapid growth of the PR8 virus in lung tissues. Consequently, we have characterized the cellular inflammatory response following inoculation into the per..