title: Lesional T-cell subset in leprosy and leprosy reaction.
abstract: BACKGROUND
  The T-cell-mediated immune response plays an important role in leprosy. The in situ proportion and pattern of distribution of T-cell subsets in leprosy skin lesions have been studied, but no conclusion could be drawn.
  
  
  METHODS
  We used monoclonal antibodies for T-helper and T-suppressor surface antigen to define the nature of dermal infiltration in 17 cases of nonreactional leprosy and 20 cases of reactional leprosy.
  
  
  RESULTS
  We found T helper admixed with T suppressor in an aggregated pattern in the granulomas of most cases of nonreactional leprosy and in type I reactional leprosy, but a diffuse infiltrate throughout the dermis of type II reactional leprosy. The T-helper/suppressor ratio was 1.68 in tuberculoid and 1.5 in lepromatous cases. The T-helper/ suppressor ratios of borderline tuberculoid (3.11) and type I reactional leprosy (2.54) were not statistically different. The T-helper/suppressor ratio of type II reactional leprosy (5.83) was statistically higher than nonreactional lepromatous cases.
  
  
  CONCLUSIONS
  The alteration of the T-helper/suppressor ratio in our study is mainly due to the reduction of T-suppressor cells in the dermal infiltrates, especially in type II reactional leprosy. Further studies of T-suppressor functions may be important in the pathogenesis of leprosy.
authors.affiliation: Department of Dermatology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: P
authors.initials: P
authors.lastname: Mahaisavariya
authors.forename: K
authors.initials: K
authors.lastname: Kulthanan
authors.forename: S
authors.initials: S
authors.lastname: Khemngern
authors.forename: S
authors.initials: S
authors.lastname: Pinkaew
mesh_terms: D015704:CD4 Antigens / Q000032:analysis; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D016827:CD8 Antigens / Q000032:analysis; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007918:Leprosy / Q000276:immunology* / Q000473:pathology; D018655:Lymphocyte Count; D008297:Male; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens