A. Mouhoub et al., LIGATION OF CR-1 (C3B RECEPTOR, CD35) ON CD4(-LYMPHOCYTES ENHANCES VIRAL REPLICATION IN HIV-INFECTED CELLS() T), Clinical and experimental immunology, 106(2), 1996, pp. 297-303
The present study provides evidence for a role of the C3b receptor, CR
1 (CD35), in activation of HIV replication in CD4(+) T lymphocytes. Li
gation of CRI with cross-linked anti-receptor MoAbs or with aggregated
C3b enhanced transcription of viral genes and the release of p24 and
RT activity from cultures of purified normal CD4(+) T lymphocytes that
had been infected with HIV-1 in vitro. No effect was observed upon li
gation of CR2 (CD21), a C3 receptor that is also expressed on human CD
4(+) T cells. Cross-linking of CR1 also enhanced HIV replication in pe
ripheral blood CD4(+) lymphocytes isolated from HIV+ individuals. The
enhancing effect of CR1 was not related to a mitogenic effect induced
by stimulation of the receptor on T cells. The CR1 specificity of the
enhancing effect was established by the observation that the addition
of soluble recombinant CR1 to the cultures abolished the enhancement o
f p24 release induced by anti-CR1 MoAbs. Our results suggest that HIV
replication may be triggered in resting HIV-infected CD4(+) T lymphocy
tes through interaction with C3b-bearing immune complexes or particles
.