Open AccessT-Tropic Sequence of the V3 Loop Is Critical for HIV-1 Infection of CXCR4-Positive Colonic HT-29 Epithelial Cells
Author(s) -
J Roberto Trujillo,
Nathalie V. Goletiani,
Irene Bosch,
Colleen Kendrick,
Rick A. Rogers,
Elaine B. Trujillo,
Max Essex,
Joseph D. Brain
Publication year - 2000
Publication title -
journal of acquired immune deficiency syndromes
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.162
H-Index - 157
eISSN - 1944-7884
pISSN - 1525-4135
DOI - 10.1097/00042560-200009010-00001
Subject(s) - v3 loop , cxcr4 , biology , infectivity , virology , antibody , cxc chemokine receptors , reverse transcriptase , chemokine receptor , chemokine , viral entry , immunostaining , cell culture , virus , microbiology and biotechnology , viral replication , immunology , epitope , immune system , rna , gene , immunohistochemistry , biochemistry , genetics
Some colonic and neuronal cells which are CD4- but galactosyl ceramide-positive are susceptible to infection with HIV-1. We have previously shown that the T-cell tropic V3 loop of HIV-1 gp120 serves as a primary viral determinant for infectivity of CD4- neuronal cells. However, the nature of the V3 loop of HIV-1 needed for infection and the V3 loop's interaction with coreceptors on colonic epithelial cells have not been fully analyzed. By using HIV-1 molecular clones, we show that the T-cell tropic V3 domain is critical for HIV-1 infection of colonic HT-29 epithelial cells. Because T-cell tropic HIV-1 can use CXCR4 as a coreceptor in T cells, we set out to determine the role of CXCR4 during infection of HT-29 cells. Using reverse transcriptase-polymerase chain reaction (RT-PCR) and immunostaining, we show that these epithelial cells of colonic origin express the chemokine receptor CXCR4. Importantly, antibody against CXCR4 or a neutralizing antibody against HIV-1 gp120 V3 loop blocks T-cell tropic HIV-1 entry into HT-29 cells. These data indicate that the V3 loop of HIV-1 and the chemokine receptor CXCR4 are both critical for HIV-1 infection of colonic HT-29 epithelial cells. An HIV-1 T-tropic virus may be responsible for the infection of human colonic epithelial cells in vivo.