HLA-G and NK receptor are expressed in psoriatic skin: a possible pathway for regulating infiltrating T cells?

Am J Pathol. 2001 Jul;159(1):71-7. doi: 10.1016/S0002-9440(10)61675-6.

Abstract

Recent data have suggested that in psoriasis, the T-infiltrating cells could be submitted to regulatory pathways, possibly through natural killer receptors. HLA-G binds to different natural killer receptors and is able to inhibit T-cell functions. Because this molecule is induced by interferon-gamma, a major cytokine in psoriasis, we asked whether HLA-G and its receptor might be expressed in this disease. Specific RNAs for HLA-G1 and HLA-G5 were consistently found in lesional skin specimens, soluble HLA-G5 transcripts being found only in psoriasis. HLA-G protein was found in all psoriatic sections, but never in normal skin controls. Double labeling demonstrated that HLA-G-positive cells were CD68(+), CD11c(+) macrophages. The NKR ILT2 was also present in psoriatic skin, the T CD4(+)-infiltrating cells expressing indeed ILT2. The demonstration of HLA-G and ILT2 expression in psoriatic skin suggests that this pathway may act as an inhibitory feed back aimed to down-regulate the deleterious effects of T-cell infiltrate in this disease.

MeSH terms

  • Alternative Splicing
  • Antigens, CD / metabolism
  • Antigens, Differentiation, Myelomonocytic / metabolism
  • CD4-Positive T-Lymphocytes / metabolism
  • Female
  • HLA Antigens / genetics
  • HLA Antigens / metabolism*
  • HLA Antigens / physiology
  • HLA-G Antigens
  • Histocompatibility Antigens Class I / genetics
  • Histocompatibility Antigens Class I / metabolism*
  • Histocompatibility Antigens Class I / physiology
  • Humans
  • Integrin alphaXbeta2 / metabolism
  • Leukocyte Immunoglobulin-like Receptor B1
  • Lymphocytes, Tumor-Infiltrating / physiology
  • Macrophages / metabolism
  • Psoriasis / metabolism*
  • Psoriasis / pathology
  • Psoriasis / physiopathology
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors, Immunologic / metabolism*
  • Receptors, Immunologic / physiology
  • Reference Values
  • Skin / metabolism*
  • Skin / pathology
  • T-Lymphocytes / physiology

Substances

  • Antigens, CD
  • Antigens, Differentiation, Myelomonocytic
  • CD68 antigen, human
  • HLA Antigens
  • HLA-G Antigens
  • Histocompatibility Antigens Class I
  • Integrin alphaXbeta2
  • LILRB1 protein, human
  • Leukocyte Immunoglobulin-like Receptor B1
  • NKTR protein, human
  • RNA, Messenger
  • Receptors, Immunologic