Research

Differential susceptibility of naïve, central memory and effector memory T cells to dendritic cell-mediated HIV-1 transmission

Fedde Groot^1,2 , Toni MM van Capel² , Joost HN Schuitemaker² , Ben Berkhout¹ and Esther C de Jong²

¹  Dept. of Human Retrovirology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands

²  Dept. of Cell Biology and Histology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands

author email corresponding author email

Retrovirology 2006, 3:52doi:10.1186/1742-4690-3-52

Published:	17 August 2006

Abstract

Background

Dendritic cells (DC) have been proposed to facilitate sexual transmission of HIV-1 by capture of the virus in the mucosa and subsequent transmission to CD4⁺ T cells. Several T cell subsets can be identified in humans: naïve T cells (T_N) that initiate an immune response to new antigens, and memory T cells that respond to previously encountered pathogens. The memory T cell pool comprises central memory (T_CM) and effector memory cells (T_EM), which are characterized by distinct homing and effector functions. The T_EM cell subset, which can be further divided into effector Th1 and Th2 cells, has been shown to be the prime target for viral replication after HIV-1 infection, and is abundantly present in mucosal tissues.

Results

We determined the susceptibility of T_N, T_CM and T_EM cells to DC-mediated HIV-1 transmission and found that co-receptor expression on the respective T cell subsets is a decisive factor for transmission. Accordingly, CCR5-using (R5) HIV-1 was most efficiently transmitted to T_EM cells, and CXCR4-using (X4) HIV-1 was preferentially transmitted to T_N cells.

Conclusion

The highly efficient R5 transfer to T_EM cells suggests that mucosal T cells are an important target for DC-mediated transmission. This may contribute to the initial burst of virus replication that is observed in these cells. T_N cells, which are the prime target for DC-mediated X4 virus transmission in our study, are considered to inefficiently support HIV-1 replication. Our results thus indicate that DC may play a decisive role in the susceptibility of T_N cells to X4 tropic HIV-1.