TY - JOUR
T1 - HIV-1 and SIV predominantly use CCR5 expressed on a precursor population to establish infection in T follicular helper cells
AU - Xu, Yin
AU - Phetsouphanh, Chansavath
AU - Suzuki, Kazuo
AU - Aggrawal, Anu
AU - Graff-Dubois, Stephanie
AU - Roche, Michael
AU - Bailey, Michelle
AU - Alcantara, Sheilajen
AU - Cashin, Kieran
AU - Sivasubramaniam, Rahuram
AU - Koelsch, Kersten K.
AU - Autran, Brigitte
AU - Harvey, Richard
AU - Gorry, Paul R.
AU - Moris, Arnaud
AU - Cooper, David A.
AU - Turville, Stuart
AU - Kent, Stephen J.
AU - Kelleher, Anthony D.
AU - Zaunders, John
N1 - Copyright the Author(s) 2017. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
PY - 2017/4/21
Y1 - 2017/4/21
N2 - Background: T follicular helper (Tfh) cells are increasingly recognized as a major reservoir of HIV infection that will likely need to be addressed in approaches to curing HIV. However, Tfh express minimal CCR5, the major coreceptor for HIV-1, and the mechanism by which they are infected is unclear. We have previously shown that macaque Tfh lack CCR5, but are infected in vivo with CCR5-using SIV at levels comparable to other memory CD4+ T cells. Similarly, human splenic Tfh cells are highly infected with HIV-1 DNA. Therefore, we set out to examine the mechanism of infection of Tfh cells. Methodology: Tfh and other CD4+ T cell subsets from macaque lymph nodes and spleens, splenic Tfh from HIV+ subjects, and tonsillar Tfh from HIV-uninfected subjects were isolated by cell sorting prior to cell surface and molecular characterization. HIV proviral gp120 sequences were submitted to genotypic and phenotypic tropism assays. Entry of CCR5- and CXCR4-using viruses into Tfh from uninfected tonsillar tissue was measured using a fusion assay. Results: Phylogenetic analysis, genotypic, and phenotypic analysis showed that splenic Tfh cells from chronic HIV+ subjects were predominantly infected with CCR5-using viruses. In macaques, purified CCR5+PD-1intermediate(int)+ memory CD4+ T cells were shown to include pre-Tfh cells capable of differentiating in vitro to Tfh by upregulation of PD-1 and Bcl6, confirmed by qRT-PCR and single-cell multiplex PCR. Infected PD-1int cells survive, carry SIV provirus, and differentiate into PD-1hi Tfh after T cell receptor stimulation, suggesting a pathway for SIV infection of Tfh. In addition, a small subset of macaque and human PD-1hi Tfh can express low levels of CCR5, which makes them susceptible to infection. Fusion assays demonstrated CCR5-using HIV-1 entry into CCR5+ Tfh and pre-Tfh cells from human tonsils. Conclusion: The major route of infection of Tfh in macaques and humans appears to be via a CCR5-expressing pre-Tfh population. As the generation of Tfh are important for establishing effective immune responses during primary infections, Tfh are likely to be an early target of HIV-1 following transmission, creating an important component of the reservoir that has the potential to expand over time.
AB - Background: T follicular helper (Tfh) cells are increasingly recognized as a major reservoir of HIV infection that will likely need to be addressed in approaches to curing HIV. However, Tfh express minimal CCR5, the major coreceptor for HIV-1, and the mechanism by which they are infected is unclear. We have previously shown that macaque Tfh lack CCR5, but are infected in vivo with CCR5-using SIV at levels comparable to other memory CD4+ T cells. Similarly, human splenic Tfh cells are highly infected with HIV-1 DNA. Therefore, we set out to examine the mechanism of infection of Tfh cells. Methodology: Tfh and other CD4+ T cell subsets from macaque lymph nodes and spleens, splenic Tfh from HIV+ subjects, and tonsillar Tfh from HIV-uninfected subjects were isolated by cell sorting prior to cell surface and molecular characterization. HIV proviral gp120 sequences were submitted to genotypic and phenotypic tropism assays. Entry of CCR5- and CXCR4-using viruses into Tfh from uninfected tonsillar tissue was measured using a fusion assay. Results: Phylogenetic analysis, genotypic, and phenotypic analysis showed that splenic Tfh cells from chronic HIV+ subjects were predominantly infected with CCR5-using viruses. In macaques, purified CCR5+PD-1intermediate(int)+ memory CD4+ T cells were shown to include pre-Tfh cells capable of differentiating in vitro to Tfh by upregulation of PD-1 and Bcl6, confirmed by qRT-PCR and single-cell multiplex PCR. Infected PD-1int cells survive, carry SIV provirus, and differentiate into PD-1hi Tfh after T cell receptor stimulation, suggesting a pathway for SIV infection of Tfh. In addition, a small subset of macaque and human PD-1hi Tfh can express low levels of CCR5, which makes them susceptible to infection. Fusion assays demonstrated CCR5-using HIV-1 entry into CCR5+ Tfh and pre-Tfh cells from human tonsils. Conclusion: The major route of infection of Tfh in macaques and humans appears to be via a CCR5-expressing pre-Tfh population. As the generation of Tfh are important for establishing effective immune responses during primary infections, Tfh are likely to be an early target of HIV-1 following transmission, creating an important component of the reservoir that has the potential to expand over time.
KW - CCR5
KW - CD4
KW - germinal center
KW - HIV-1
KW - T follicular helper cells
UR - http://www.scopus.com/inward/record.url?scp=85018446302&partnerID=8YFLogxK
U2 - 10.3389/fimmu.2017.00376
DO - 10.3389/fimmu.2017.00376
M3 - Article
C2 - 28484447
AN - SCOPUS:85018446302
SN - 1664-3224
VL - 8
SP - 1
EP - 15
JO - Frontiers in Immunology
JF - Frontiers in Immunology
M1 - 376
ER -