asialo-gm1-ganglioside and Orthomyxoviridae-Infections

Mice injected intracerebrally with infectious influenza virus (60 hemagglutinin units) developed lethargy, seizures, comas, and died 2 to 5 days postinfection. As early as 6 h after infection, the cerebrospinal fluid (CSF) in these animals was infiltrated with polymorphonuclear cells, mononuclear leukocytes, and large granular lymphocytes. Potent natural killer (NK) cell activity was observed for both CSF and spleen cell populations over the same period. This NK cell activity correlated with interferon (IFN) levels in the CSF and serum. Treatment of lethally infected mice with either anti-IFN alpha-IFN beta or anti-ganglio-n-tetraoglyceramide antiserum ameliorated the disease, reduced mortality, and effected changes in the relative proportions of inflammatory cell populations infiltrating the CSF. The possible significance of IFN and NK cell activity in the development of this influenza virus-induced encephalopathy is discussed.

Topics: Animals; Brain Diseases; G(M1) Ganglioside; Glycosphingolipids; Immunologic Techniques; Influenza A virus; Interferons; Killer Cells, Natural; Kinetics; Male; Mice; Mice, Inbred BALB C; Orthomyxoviridae Infections

The role of natural killer (NK) cells in host defenses against influenza virus infections in the lung was investigated by using rabbit antiserum to asialo GM1 (RAGM1), a neutral glycosphingolipid expressed on the plasma membrane of NK cells and some mouse pulmonary macrophages. Intravenous or intratracheal (i.t.) administration of RAGM1 resulted in depletion of the (in vitro) NK activity in lung and spleen or lung alone, respectively. The NK activity was depleted as early as 12 hr post-inoculation of antiserum, but returned to the normal range of activity by 4 days after antibody administration. RAGM1 serum treatment had no effect on the cytotoxic macrophage activity expressed by the plastic-adherent mononuclear cell populations isolated from mouse or hamster lung. Treatment of mice or hamsters with an i.t. or i.v. inoculation of RAGM1 rendered both species of laboratory animals susceptible to increased morbidity and mortality during a pulmonary influenza infection. These data support the hypothesis that a population of NK cells exist in an extravascular compartment within the lung, and that this local population of NK cells in the lung is crucial to the early natural pulmonary defenses during influenza infection.

Topics: Animals; Cricetinae; Cytotoxicity, Immunologic; Female; G(M1) Ganglioside; Glycosphingolipids; Immune Sera; Immunity, Innate; Immunization, Passive; Influenza A virus; Killer Cells, Natural; Macrophages; Mice; Mice, Inbred Strains; Orthomyxoviridae Infections; Pneumonia, Viral; Rabbits; Species Specificity