Site of Intracellular Antigen Production by Myxoviruses.

Abstract

The multiplication cycles of Sendai, mumps, and Newcastle disease viruses were compared with that of influenza A virus in regard to site of antigen production in cultured cells. Single-cycle infections were followed in chick embryo lung cells and in human conjunctiva cells using fluorescent antibodies prepared from infection-convalescent immune sera shown to contain anti-S and anti-V antibodies. In cells infected with influenza A virus antigen was first detectable in the nucleus and became abundant there by the time antigen appeared in the cytoplasm. In cells infected with Sendai, mumps, or Newcastle disease viruses earliest detectable antigen was found as small granules scattered throughout the cytoplasm. Antigen granules increased in size and number to form large cytoplasmic aggregates and masses. Multiplication of Sendai, mumps, or Newcastle disease viruses did not include production of antigen in the nucleus detectable by fluorescent antibody at any stage of the cycle.