Primary murine neurons as in vitro model for studying neuroinfections caused by human adenoviruses

Adenoviral infections of the central nervous system are rare, but they are characteristic for their high mortality rate. People with impaired immunity and children are particularly vulnerable. A few reports of neuroinfections caused by adenoviruses are found in literature. In this study the tropism of the human adenoviruses type 4, 5, 7 to primary cultures of murine neurons and the influence of infection on the neuron morphology and actin cytoskeleton was examined. The A549 non-small-cell lung cancer cell line was used as a reference line. Viral effects upon the cell culture were evaluated by direct immunofluorescence. The levels of adenovirus replication in the above-mentioned cell cultures were determined by real-time PCR. In the current study we demonstrated for the first time that human adenovirus (HAdV) type 4, 5 and 7 exhibits tropism for neurons cultured in vitro followed by the extensive replication of all serotypes in the primary culture of murine neurons. Immunofluorescent labelling and confocal microscopy revealed the changes in cell morphology, destruction of actin cytoskeleton and cell lysis as the final stage of infection. According to the obtained results we can assume that productive cycle of HAdV in the studied cell cultures occurred. We also observed accumulation of nuclear actin within nuclei of infected cells which may indicate that it plays role in adenovirus infection and replication in neurons and A549 cells.