Coexpression of CCR5 and IL-2 in human genital but not blood T cells: implications for the ontogeny of the CCR5+ Th1 phenotype

J Immunol. 1999 Aug 15;163(4):2306-13.

Abstract

Memory T cells that home to inflamed tissues typically express the beta-chemokine receptor CCR5 and exhibit a Th1 cytokine profile. The migration of these cells into the genital tract following antigenic exposure has particular relevance to acquisition of HIV-1 infection, because CCR5 functions as the coreceptor for most sexually transmitted HIV-1 strains. We recently established methodology to purify and culture mononuclear cells from the female reproductive tract, and here we analyzed the phenotype, CCR5 expression, and cytokine production of cervicovaginal T cells in up to 16 donors. The proportion of mucosal T cells expressing CCR5 was markedly expanded as compared with peripheral blood (mean 88% vs 24% in 13 donors), but the receptor density on individual CCR5+ T cells was only slightly increased (mean 5837 vs 4191 MEPE (molecules of equivalent PE) units in 6 of 7 donors). Intracellular costaining for IL-2, IFN-gamma, IL-4, and IL-5 revealed a Th1-type pattern in cervical T cells, with significantly higher percentages of IL-2- and IFN-gamma-producing T cells in the mucosa than in blood (mean 67% vs 29%). Coexpression of surface CCR5 with intracellular IL-2 and IFN-gamma was observed only among T cells in the mucosa, but not among those in circulation. Thus, we postulate that T cell homing to the genital mucosa leads to differentiation into the combined CCR5+ Th1 phenotype. Moreover, the predominance of CCR5+ Th1-type T cells in normal cervical mucosa provides targets accessible for the efficient transmission of macrophage-tropic HIV-1 variants in women following sexual exposure.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antigens, CD / biosynthesis
  • Antigens, CD / blood
  • Antigens, Differentiation, T-Lymphocyte / biosynthesis
  • Antigens, Differentiation, T-Lymphocyte / blood
  • Cell Separation
  • Cervix Uteri / cytology
  • Cervix Uteri / metabolism*
  • Female
  • Humans
  • Immunophenotyping
  • Interferon-gamma / biosynthesis
  • Interferon-gamma / blood
  • Interleukin-2 / biosynthesis*
  • Interleukin-2 / blood
  • Lectins, C-Type
  • Leukocyte Common Antigens / biosynthesis
  • Leukocyte Common Antigens / blood
  • Mucous Membrane / cytology
  • Mucous Membrane / metabolism
  • Receptors, Antigen, T-Cell, alpha-beta / biosynthesis
  • Receptors, Antigen, T-Cell, alpha-beta / blood
  • Receptors, CCR5 / biosynthesis*
  • Receptors, CCR5 / blood
  • Receptors, Lymphocyte Homing / biosynthesis
  • Receptors, Lymphocyte Homing / blood
  • T-Lymphocyte Subsets / immunology
  • T-Lymphocyte Subsets / metabolism
  • Th1 Cells / metabolism*
  • Vagina / cytology
  • Vagina / metabolism*

Substances

  • Antigens, CD
  • Antigens, Differentiation, T-Lymphocyte
  • CD69 antigen
  • Interleukin-2
  • Lectins, C-Type
  • Receptors, Antigen, T-Cell, alpha-beta
  • Receptors, CCR5
  • Receptors, Lymphocyte Homing
  • Interferon-gamma
  • Leukocyte Common Antigens