Insufficient resistance of trehalose-6,6'-dimycolate-treated T-cell receptor δ gene mutant (TCR δ(-/-)) mice against influenza virus infection

Abstract

Normal mice inoculated intravenously with 50 μg trehalose-6,6'- dimycolate, a glycolipid component of the cell wall of Mycobacterium, in an oil-in-water emulsion (TDM emulsion) acquired a high resistance to intranasal lethal infection of an influenza virus. In contrast, TDM emulsion-treated T- cell receptor δ gene mutant (TCR δ(-/-)) mice acquired insufficient resistance against the lethal influenza virus infection. The patterns of insufficient resistance were identical to the results obtained previously with mice which were depleted of T-lymphocytes bearing γδ T-cell receptors (γδ T-cells) by in vivo administration of anti-γδ T-cell receptor monoclonal antibody (Hoq et al, J. Gen. Virol. 78: 1597-1603, 1997). These results strongly suggest that the γδ T-cells play an important non-specific role in resistance against influenza virus infection.