DC-specific ICAM-3-grabbing nonintegrin mediates internalization of HIV-1 into human podocytes

Am J Physiol Renal Physiol. 2010 Sep;299(3):F664-73. doi: 10.1152/ajprenal.00629.2009. Epub 2010 Jul 14.

Abstract

Human immunodeficiency virus (HIV)-1 has been demonstrated to contribute to the pathogenesis of HIV-associated nephropathy. In renal biopsy studies, podocytes have been reported to be infected by HIV-1. However, the mechanism involved in HIV-1 internalization into podocytes is not clear. In the present study, we evaluated the occurrence of HIV-1 internalization into conditionally immortalized human podocytes and the mechanism involved. Human podocytes rapidly internalized R5 and X4 HIV-1 primary strains via an endocytosis-dependent pathway, without establishing a productive infection. The HIV-1 internalization was dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) receptor mediated. The role of DC-SIGN was confirmed by using specific blocking antibodies and transfection with small interfering (si) RNA/DC-SIGN. Since podocyte HIV-1 trafficking was not altered by pH-modulating agents, it appeared that HIV-1 routing occurred through nonacid vesicular compartments. Interestingly, transfection of podocytes with neither siRNA/caveolin-1 nor siRNA/clathrin heavy chain inhibited podocyte viral accumulation. Thus it appears that clathrin-coated vesicles and caveosomes may not be contributing to HIV-1-associated membrane traffic.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Caveolin 1 / genetics
  • Cell Adhesion Molecules / physiology*
  • Cells, Cultured
  • Clathrin / genetics
  • Endocytosis / physiology
  • HIV-1 / physiology*
  • Humans
  • Hydrogen-Ion Concentration
  • Lectins, C-Type / physiology*
  • Podocytes / cytology
  • Podocytes / virology*
  • RNA, Small Interfering / genetics
  • Receptors, Cell Surface / physiology*
  • Transfection
  • Virus Internalization*

Substances

  • CAV1 protein, human
  • Caveolin 1
  • Cell Adhesion Molecules
  • Clathrin
  • DC-specific ICAM-3 grabbing nonintegrin
  • Lectins, C-Type
  • RNA, Small Interfering
  • Receptors, Cell Surface