Recovery from a viral respiratory infection. I. Influenza pneumonia in normal and T-deficient mice
Wells, M.A.; Albrecht, P.; Ennis, F.A.
Journal of Immunology 126(3): 1036-1041
1981
ISSN/ISBN: 0022-1767 PMID: 6970211 Document Number: 180533
The immune responses of the host to a viral respiratory tract infection were analyzed. In a comparative study, inbred BALB/c and nude (athymic mice bred on a BALB/c background) mice were infected intranasally with mouse adapted A/Port Chalmers/1/73 influenza virus. Survival was prolonged in the nude mide (16 days vs. 10 days for BALB/c mice, t [Student's t distribution parameters] = 3.5, P < 0.01), but significantly fewer of the nude mice survived 21 days (16% vs. 42% of BALB/c mice). In addition, virus persisted longer in the lungs of nude mice (5.8 log10 of infectious virus on day 21 vs. no detectable virus in BALB/c mice) and lung pathology progressed more slowly but lasted longer in nude mice, as measured by immunofluorescent and histologic pulmonary tissue examination. Antibody production was significantly lower and there was no cytotoxic T cell response detected in lymphoid cells prepared from the spleens, peripheral blood, or the lung after nude mice infection. A significant increase in the lymphocytes number isolated from the lung was observed by day 7 (t = 5.8, P < 0.001) in the BALB/c mice but not until day 14 (t = 4.9, P < 0.001) in the nude mice. Lymphocytes from nude mice did not respond to influenza virus antigens or concanavalin A but did respond to lipopolysaccharide, whereas lymphocytes from BALB/c mice responded to all 3 preparations.