Article Text

Download PDFPDF
Th9 cytokines response and its possible implications in the immunopathogenesis of leprosy
  1. Jorge Rodrigues de Sousa1,
  2. Carla Pagliari2,
  3. Dandara Simone Maia de Almeida1,
  4. Luiz Fernando Lima Barros2,
  5. Francisca Regina Oliveira Carneiro3,
  6. Leonidas Braga Dias Jr3,
  7. Tinara Leila de Souza Aarão1,
  8. Juarez Antonio Simões Quaresma1,3
  1. 1Tropical Medicine Center, Federal do Para University, Belem, Brazil
  2. 2Facult of Medicine, Sao Paulo University, São Paulo, Brazil
  3. 3Center of Health and Biological Sciences, State University of Para, Belem, Brazil
  1. Correspondence to Dr Juarez Antonio Simões Quaresma, Tropical Medicine Center, UFPA, Av. Generalissimo Deodoro 92, Umarizal, Belem, Para 66055-190, Brazil; juarez{at}


Aims Leprosy is an infectious-contagious disease whose clinical evolution depends on the interaction of the infectious agent with the immune response of the host, leading to a clinical spectrum that ranges from lepromatous leprosy (susceptibility, LL) to tuberculoid leprosy (resistance, TT). The immune response profile will depend on the pattern of cytokine production and on the activity of macrophages during infection. Classically, the clinical evolution of leprosy has been associated with Th1/Th2 cytokine profiles, but the role of new cytokine profiles such as T helper 9 (Th9) remains to be elucidated.

Methods To evaluate the tissue expression profile of these cytokines, a cross-sectional study was conducted using a sample of 30 leprosy skin lesion biopsies obtained from patients with leprosy, 16 TT and 14 lepromatous LL.

Results Immunohistochemical analysis revealed a significant difference in interleukin (IL)-9, IL-4 transforming growth factor (TGF)-β and IL-10 levels between the two groups. IL-9 was more expressed in TT lesions compared with LL lesions. Higher expression of IL-4, IL-10 and TGF-β was observed in LL compared with TT. IL-4, IL-10 and TGF-β tended to be negatively correlated with the expression of IL-9, indicating a possible antagonistic activity in tissue.

Conclusions The results suggest that Th9 lymphocytes may be involved in the response to Mycobacterium leprae, positively or negatively regulating microbicidal activity of the local immune system in the disease.


Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Handling editor Stephen Jolles

  • Contributors JRdS, CP, LFLB, DSMdA conceived and designed the study. JRdS, FROC, LBD, TLdSA, JASQ analysed and interpreted the related results, and drafted the manuscript.

  • Competing interests None declared.

  • Patient consent Obtained.

  • Ethics approval Ethics Committee of the Nucleus of Tropical Medicine, Federal do Para University (number 047/2008).

  • Provenance and peer review Not commissioned; externally peer reviewed.