The dichotomy between herpes simplex virus type 1-induced ocular pathology and systemic immunity

Herpes simplex virus Type 1 (HSV-1) was injected into the mouse eye by the intravitreal (into the vitreous chamber; VC) or translimbal (across the limbus into the anterior chamber; TxL) route. These routes were compared for ocular pathology and systemic immunity. After VC inoculation, the virus-injected eye developed a viral infection, with the majority of opposite, uninjected eyes remaining intact and free of virus over the 4 week period of observation. In contrast, following translimbal inoculation, the entire virus-injected eye developed infection and inflammation together with subsequent chorioretinitis in the opposite uninjected eye. Systemic immunity induced by VC or TxL virus inoculation was similar to the effects of anterior chamber (AC) inoculation of the same dose of HSV-1: T cell-mediated DTH responses were suppressed while levels of anti-HSV neutralizing antibody were enhanced, compared to subcutaneously primed positive control mice. These findings demonstrate that HSV-1-induced ocular pathology does not necessarily correlate directly with systemic immunity.