title: Human beta-defensin 3 is up-regulated in cutaneous leprosy type 1 reactions.
abstract: BACKGROUND
  Leprosy, a chronic granulomatous disease affecting the skin and nerves, is caused by Mycobacterium leprae (M. leprae). The type of leprosy developed depends upon the host immune response. Type 1 reactions (T1Rs), that complicate borderline and lepromatous leprosy, are due to an increase in cell-mediated immunity and manifest as nerve damage and skin inflammation. Owing to the increase in inflammation in the skin of patients with T1Rs, we sought to investigate the activation of the innate immune system during reactionary events. Specifically, we investigated the expression levels of human beta-defensins (hBDs) 2 and 3 in the skin of patients with T1Rs, in keratinocytes, and in macrophages stimulated with M. leprae and corticosteroids.
  
  
  RESULTS
  Skin biopsies from twenty-three patients with Type 1 reactions were found to have higher transcript levels of hBD3 as compared to fifteen leprosy patients without Type 1 reactions, as measured by qPCR. Moreover, we observed that keratinocytes but not macrophages up-regulated hBD2 and hBD3 in response to M. leprae stimulation in vitro. Corticosteroid treatment of patients with T1Rs caused a suppression of hBD2 and hBD3 in skin biopsies, as measured by qPCR. In vitro, corticosteroids suppressed M. leprae-dependent induction of hBD2 and hBD3 in keratinocytes.
  
  
  CONCLUSIONS
  This study demonstrates that hBD3 is induced in leprosy Type 1 Reactions and suppressed by corticosteroids. Furthermore, our findings demonstrate that keratinocytes are responsive to M. leprae and lend support for additional studies on keratinocyte innate immunity in leprosy and T1Rs.
  
  
  BACKGROUND
  Controlled-Trials.com ISRCTN31894035.
authors.affiliation: Faculty of Infectious Tropical Diseases, Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom. cogen.a@gmail.com
authors.forename: Anna L
authors.initials: AL
authors.lastname: Cogen
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Walker
authors.forename: Chrissy H
authors.initials: CH
authors.lastname: Roberts
authors.forename: Deanna A
authors.initials: DA
authors.lastname: Hagge
authors.forename: Kapil D
authors.initials: KD
authors.lastname: Neupane
authors.forename: Saraswoti
authors.initials: S
authors.lastname: Khadge
authors.forename: Diana N J
authors.initials: DN
authors.lastname: Lockwood
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D001706:Biopsy; D002478:Cells, Cultured; D020869:Gene Expression Profiling; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D015603:Keratinocytes / Q000276:immunology / Q000382:microbiology; D015440:Leprosy, Lepromatous / Q000276:immunology*; D008264:Macrophages / Q000276:immunology / Q000382:microbiology; D009166:Mycobacterium leprae / Q000276:immunology*; D060888:Real-Time Polymerase Chain Reaction; D015854:Up-Regulation; D023083:beta-Defensins / Q000096:biosynthesis*
chemical_list: D000305:Adrenal Cortex Hormones; C422950:DEFB103A protein, human; C106641:DEFB4A protein, human; D007166:Immunosuppressive Agents; D023083:beta-Defensins