Skip to content

Advertisement

  • Poster presentation
  • Open Access

Increased CXCR4-dependent HIV-1 Fusion in Activated T Cells: Role of CD4/CXCR4 Association

  • 1Email author,
  • 1,
  • 1,
  • 1 and
  • 1
Retrovirology20052(Suppl 1):P143

https://doi.org/10.1186/1742-4690-2-S1-P143

Published: 8 December 2005

Keywords

  • Molecular Weight
  • Western Blot
  • Infectious Disease
  • Cell Surface
  • Cancer Research

Activation of peripheral T cells resulted in enhanced fusion with X4 HIV-1 env-expressing cells without increases in the surface CD4 or CXCR4. Biochemical methods and biological assays were used to correlate the increased fusion of activated T cells with changes in CXCR4 isoforms and CD4-CXCR4 association. CXCR4 species with molecular weight of 47, 50, 62, and 98 kDa were identified in resting T cells by western blot. Stimulation with PHA/IL2 induced a reduction in the 47 kDa, and an increase in the amounts of 50 and ubiquitinated 62–64 kDa CXCR4, and in the co-precipitation of the 62 kDa CXCR4 with CD4. Striping of CD4 from the cell surface prior to cell lysis only partially reduced co-precipitation of CD4 with the 62 kDa CXCR4, revealing a pool of intracellular CD4-CXCR4 complexes. Brefeldin A and monensin reduced co-precipitation of CXCR4 with CD4, suggesting that late endosomes play a role in intracellular association of CXCR4 with CD4. Our data demonstrated a correlation between the enhanced susceptibility of activated T cells to HIV-1 fusion and an increase in CXCR4-CD4 complexes that may shuttle between late endosomes and the cell surface.

Notes

Authors’ Affiliations

(1)
Division of Viral Products, CBER and Division of Monoclonal Antibodies, CDER, FDA, Maryland, USA

Copyright

© The Author(s) 2005

Advertisement