Fibronectin involvement following herpes simplex infection of cultured rat astrocytes

To evaluate the potential impact of a strongly neurotropic virus on the matricial fibronectin (FN) of a given neural cell type, first subculture of rat astrocytes were inoculated with either a low (0.1-0.5) or a high MOI (10-100) of Herpes simplex virus-type 1 (HSV-1). Infected samples, as well as matched controls, were harvested from 12 to 72 h post-inoculation and processed for extracellular FN labeling by the peroxidase-antiperoxidase (PAP) method. Following low MOI, multinucleated cell formation and syncytial development drastically modified peripheral FN, since the typical loose network was largely replaced by a patch-like appearance. At high MOI, when viral action caused further cytoplasmic retraction leading to rounded or stellate cells, the FN pattern was remarkably altered, even with total FN loss around highly retracted cells. It may be concluded that a virus such as HSV-1, capable of modifying astrocyte morphology, induces a redistribution or loss of pericellular FN.