C. Simard et al., STUDIES OF THE SUSCEPTIBILITY OF NUDE, CD4 KNOCKOUT, AND SCID MUTANT MICE TO THE DISEASE INDUCED BY THE MURINE AIDS DEFECTIVE VIRUS, Journal of virology, 71(4), 1997, pp. 3013-3022
Murine AIDS (MAIDS) is induced by a defective retrovirus that infects
lymphocyte cells of the B lineage. To determine whether functional T c
ells are required for the infection of B cells, T-cell-deficient mice
(nude, CD4 knockout, and SCID) were infected with helper-free stocks o
f the MAIDS defective virus. Infection of B cells was monitored by Nor
thern blot analysis and in situ hybridization. The C57BL/6 nude mice c
ontained clusters of infected B cells, but less so than did the euthym
ic mice. In contrast, the (C57BL/6 x BALB/c)F-1 nude mice harbored mor
e infected B cells than did their euthymic littermates when maintained
in a pathogen-free environment. Clusters of infected B cells were als
o detected in the MAIDS virus-infected CD4(-/-) knockout mice despite
the total absence of CD4(+) T cells in these mice. However, infected c
ells were not detected in SCID mice (deficient in mature T and B cells
) inoculated with the same virus, indicating that precursor B cells ar
e not a target of the virus in the absence of mature CD4(+) T cells. T
hese data confirm that the primary event in the development of MAIDS i
s the infection of relatively mature peripheral B cells and that CD4() T cells are required to promote the expansion of these infected B ce
lls.