title: Reduction of skin-homing cytotoxic T cells (CD8+ -CLA+) in patients with vitiligo.
abstract: BACKGROUND
  Vitiligo is a frequently acquired, hereditary disease, characterized by achromic macules due to the absence of melanocytes. In contrast with earlier studies, in which the main pathogenic role was attributed to anti-melanocyte antibodies, recent papers have emphasized a role for CD8(+) cytotoxic T lymphocytes in melanocyte destruction. Fifteen percent of peripheral T cell express cutaneous lymphocyte-associated antigen (CLA), responsible for skin-homing T cell. Phototherapy is used to treat patients with generalized vitiligo and it has been shown to interfere with CLA(+) T cells in other skin diseases.
  
  
  OBJECTIVE
  To describe peripheral blood T cell subpopulations' frequency and ability to express the skin-homing molecule (CLA) in patients with non-segmental vitiligo, before and after photochemotherapy (PUVA).
  
  
  METHODS
  Twenty-two patients with generalized and active spreading vitiligo were submitted to 30 PUVA-8MOP sessions. Lymphocyte immunophenotyping was performed by flow cytometry using anti-CD3, anti-CD8 and anti-CLA monoclonal antibodies. Fifteen healthy volunteers, sex- and age-matched, were included as a control group.
  
  
  RESULTS
  CD8(+) -CLA(+) T cells were significantly reduced in number in untreated vitiligo patients (P=0.008) when compared with control individuals, albeit with a more intense CLA expression (P=0.028). These findings were not altered after PUVA. No significant difference was noticed in CD4/CD8 ratios nor in CD4-CLA(+) T cell numbers between vitiligo patients and controls, both before and after PUVA.
  
  
  CONCLUSIONS
  CD8-CLA(+) T cells are reduced in peripheral blood of patients with non-segmental vitiligo. This finding may be related to the previously reported increase of CD8(+) cells in both lesions and perilesional skin of these patients.
authors.affiliation: Setor de Fotodermatologia, Serviço de Dermatologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. danielaantelo@dermatologista.net
authors.forename: Daniela Pereira
authors.initials: DP
authors.lastname: Antelo
authors.forename: Absalom Lima
authors.initials: AL
authors.lastname: Filgueira
authors.forename: José Marcos Telles
authors.initials: JM
authors.lastname: Cunha
mesh_terms: D000328:Adult; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism*; D015704:CD4 Antigens / Q000378:metabolism*; D016827:CD8 Antigens / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008544:Melanocytes / Q000276:immunology; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008875:Middle Aged; D011701:PUVA Therapy; D018709:Statistics, Nonparametric; D014820:Vitiligo / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D055815:Young Adult
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D015704:CD4 Antigens; D016827:CD8 Antigens; D008562:Membrane Glycoproteins