title: Mycobacterium avium complex infection in mice: lack of exacerbation after LP-BM5 murine leukemia virus infection.
abstract: The murine leukemia virus LP-BM5 has been used to reproduce the model of murine AIDS in order to evaluate the course of infection with the MO-1 strain of Mycobacterium avium complex (MAC). LP-BM5 was inoculated in C57BL/6 mice by intravenous (i.v.) injection either 8 weeks before an i.v. challenge with 10(3) or 10(6) CFU of MAC (coinfection 1) or 10 days after an i.v. challenge with 10(3) CFU of MAC (coinfection 2). During coinfection 2 experiments, the phenotypic alterations in blood lymphocyte subsets were analyzed. During coinfection 1, LP-BM5 infection tended to decrease the mycobacterial growth, with the difference reaching statistical significance for the lower inoculum (10(3) CFU of MAC) (P<0.001). During coinfection 2, LP-BM5 did not exacerbate MAC infection except in the spleen, at day 90 after LP-BM5 challenge (P<0.001). LP-BM5 infection and the LP-BM5-MAC coinfection increased the numbers of activated CD4+ lymphocytes (CD4+ Ly6AE+) (P<0.001), activated CD8+ lymphocytes (CD8+ Ly6AE+) (P<0.001), and activated B lymphocytes (Ly5+ Ly6AE+) (P<0.001). This activation of T lymphocytes could explain the lack of exacerbation of MAC infection and even the trend to a lower level of MAC infection. Thus, this model of retroviral infection of mice does not seem to be a reliable model of immunodepression for the study of MAC infection and its treatments.
authors.affiliation: Service des Maladies Infectieuses et Tropicales, Hôpital Raymond Poincaré, Garches, France.
authors.forename: F
authors.initials: F
authors.lastname: Grassi
authors.forename: C
authors.initials: C
authors.lastname: Perronne
authors.forename: M
authors.initials: M
authors.lastname: Levacher-Clergeot
authors.forename: Y
authors.initials: Y
authors.lastname: Cohen
authors.forename: C
authors.initials: C
authors.lastname: Maslo
authors.forename: F
authors.initials: F
authors.lastname: Chau
authors.forename: M
authors.initials: M
authors.lastname: Sinet
authors.forename: J J
authors.initials: JJ
authors.lastname: Pocidalo
mesh_terms: D000818:Animals; D005260:Female; D009052:Leukemia Virus, Murine; D016131:Lymphocyte Subsets; D051379:Mice; D008810:Mice, Inbred C57BL; D009162:Mycobacterium avium; D009929:Organ Size; D012192:Retroviridae Infections / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology*; D014412:Tumor Virus Infections / Q000276:immunology*