Requirement of MIP-1α for an Inflammatory Response to Viral Infection

Macrophage inflammatory protein-1α (MIP-1α) is a chemokine that has pro-inflammatory and stem cell inhibitory activities in vitro. Its biologic role in vivo was examined in mice in which the gene encoding MIP-1α had been disrupted. Homozygous MIP-1α mutant (-/-) mice were resistant to Coxsackievirus-induced myocarditis seen in infected wild-type (+/+) mice. Influenza virus-infected -/- mice had reduced pneumonitis and delayed clearance of the virus compared with infected +/+ mice. The -/- mice had no overt hematopoietic abnormalities. These results demonstrate that MIP-1α is an important mediator of virus-induced inflammation in vivo.