title: Lessons of leprosy: the emergence of TH17 cytokines during type II reactions (ENL) is teaching us about T-cell plasticity.
abstract: BACKGROUND
  Leprosy was the first disease classified according to the thymus derived T-cell in the 1960s and the first disease classified by the cytokine profile as intact interferon-γ (IFN-γ) and interleukin-2 (IL2) or TH1 (tuberculoid) and deficient IFN-γ and IL2 or TH2 (lepromatous), in the 1980s.
  
  
  OBJECTIVE
  In the present study, we set out to explore the T helper 17 (TH17) lymphocyte subset, the hallmark of T-cell plasticity, in skin biopsies from patients with erythema nodosum leprosum (ENL) who were treated with thalidomide.
  
  
  METHODS
  RNA was extracted from paraffin embedded tissue before and after thalidomide treatment of ENL and RT-PCR was performed.
  
  
  RESULTS
  IL17A, the hallmark of TH17, was consistently seen before and after thalidomide treatment, confirming the TH17 subset to be involved in ENL and potentially up-regulated by thalidomide.
  
  
  CONCLUSIONS
  A reduction in CD70, GARP, IDO, IL17B (IL-20), and IL17E (IL-25), coupled with increases in RORγT, ARNT, FoxP3, and IL17C (IL-21) following thalidomide treatment, opens the door to understanding the complexity of the immunomodulatory drug thalidomide, which can operate as an anti-inflammatory while simultaneously stimulating cell-mediated immunity (CMI). We conclude that TH17 is involved in the immunopathogenesis of ENL and that thalidomide suppresses inflammatory components of TH17, while enhancing other components of TH17 that are potentially involved in CMI.
authors.affiliation: Pulmonary Division, New York University Department of Medicine, New York, NY, USA. martif02@nyumc.org
authors.forename: Frank
authors.initials: F
authors.lastname: Martiniuk
authors.forename: Jerome
authors.initials: J
authors.lastname: Giovinazzo
authors.forename: Ainah U
authors.initials: AU
authors.lastname: Tan
authors.forename: Rozana
authors.initials: R
authors.lastname: Shahidullah
authors.forename: Patrick
authors.initials: P
authors.lastname: Haslett
authors.forename: Gilla
authors.initials: G
authors.lastname: Kaplan
authors.forename: William R
authors.initials: WR
authors.lastname: Levis
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D016207:Cytokines / Q000276:immunology; D004893:Erythema Nodosum / Q000188:drug therapy / Q000276:immunology*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D020381:Interleukin-17 / Q000235:genetics / Q000276:immunology; D007917:Leprostatic Agents / Q000494:pharmacology / Q000627:therapeutic use; D015440:Leprosy, Lepromatous / Q000188:drug therapy / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012313:RNA / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D058504:Th17 Cells / Q000276:immunology*; D013792:Thalidomide / Q000494:pharmacology / Q000627:therapeutic use*; D015854:Up-Regulation / Q000187:drug effects; D055815:Young Adult
chemical_list: D016207:Cytokines; D020381:Interleukin-17; D007917:Leprostatic Agents; D013792:Thalidomide; D012313:RNA