Phagocytosis and ingestion of influenza virus by human polymorphonuclear leucocytes in vitro: electronmicroscopy studies.

Interaction of human polymorphonuclear leucocytes (PMNL) and influenza virus (IFV) was studied in vitro. At 0 degree C, the viral particles were bound extensively to the surface of the PMNL membrane with a ratio of about 1000 virus particles to a single PMNL. The binding was sensitive to neuraminidase, suggesting attachment through sialo-compound receptors. At 37 degrees C, the virus particles disappeared rapidly from the cell surface, about half of them being eluted and the remainder being endocytosed into the cytoplasmic vesicles. Immuno-gold electronmicroscopy suggests that the virus particles are ingested into phagosomal vesicles and lysed.