Cytotoxicity induced by mixtures of adenovirus and specific antibodies - Induction of cytotoxic aggregates by homotypic anti-fibre sera and neutralization of the cytotoxicity by homotypic anti-hexon sera

Aggregates cytotoxie for human cells in vitro were produced when adenovirus type 5 was mixed with homotypic rabbit antiserum against whole virus particles at a certain restricted virus-antibody ratio. The same degree of cytotoxicity was obtained with mixtures of the virus and an antiserum against purified fibres of adenovirus type 5 at a certain proportion. The cytotoxicity could be neutralized by homotypic antisera against purified hexons. The sequence in which the two anti-capsomer sera were added to the virus was found to be of importance: complete neutralization of the cytotoxicity appeared when virus preparations were incubated with anti-hexon sera before cytotoxic aggregates were formed by antifibre sera. In this case even a significantly lower⁵¹Cr-release appeared than that produced by corresponding amounts of virus alone. No neutralization of the cytotoxicity was obtained when anti-hexon serum was added to the mixtures after formation of cytotoxic aggregates by anti-fibre antibodies.