Article Text

PDF
Impairment of the intestinal barrier is evident in untreated but absent in suppressively treated HIV-infected patients
  1. H-J Epple1,
  2. T Schneider1,
  3. H Troeger1,
  4. D Kunkel1,
  5. K Allers1,
  6. V Moos1,
  7. M Amasheh1,
  8. C Loddenkemper2,
  9. M Fromm3,
  10. M Zeitz1,
  11. J-D Schulzke1,4
  1. 1
    Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité-Universitätsmedizin Berlin, Berlin, Germany
  2. 2
    Institute of Pathology/Research Center ImmunoSciences (RCIS), Charité-Universitätsmedizin Berlin, Berlin, Germany
  3. 3
    Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
  4. 4
    Department of General Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
  1. Professor J-D Schulzke, Medizinische Klinik für Gastroenterologie, Infektiologie und Rheumatologie, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, D-12200 Berlin, Germany; joerg.schulzke{at}charite.de

Abstract

Background and aims: Impairment of the gastrointestinal mucosal barrier contributes to progression of HIV infection. The purpose of this study was to investigate the effect of highly active antiretroviral therapy (HAART) on the HIV-induced intestinal barrier defect and to identify underlying mechanisms.

Methods: Epithelial barrier function was characterised by impedance spectroscopy and [3H]mannitol fluxes in duodenal biopsies from 11 untreated and 8 suppressively treated HIV-infected patients, and 9 HIV-seronegative controls. The villus/crypt ratio was determined microscopically. Epithelial apoptoses were analysed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling (TUNEL) and caspase-3 staining. Tight junction protein expression was quantified by densitometric analysis of immunoblots. Mucosal cytokine production was determined by cytometric bead array.

Results: Only in untreated but not in treated HIV-infected patients, epithelial resistance was reduced (13 (1) vs 23 (2) Ω cm2, p<0.01) and mannitol permeability was increased compared with HIV-negative controls (19 (3) vs 9 (1) nm/s, p<0.05). As structural correlates, epithelial apoptoses and expression of the pore-forming claudin-2 were increased while expression of the sealing claudin-1 was reduced in untreated compared with treated patients and HIV-negative controls. Furthermore, villous atrophy was evident and mucosal production of interleukin 2 (IL2), IL4 and tumour necrosis factor α (TNFα) was increased in untreated but not in treated HIV-infected patients. Incubation with IL2, IL4, TNFα and IL13 reduced the transepithelial resistance of rat jejunal mucosa.

Conclusions: Suppressive HAART abrogates HIV-induced intestinal barrier defect and villous atrophy. The HIV-induced barrier defect is due to altered tight junction protein composition and elevated epithelial apoptoses. Mucosal cytokines are mediators of the HIV-induced mucosal barrier defect and villous atrophy.

Statistics from Altmetric.com

Footnotes

  • Funding: This work was supported by the German Research Foundation (DFG KFO grant 104).

  • Competing interests: None.

  • Ethics approval: The study was approved by the local ethics committee.

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.

Linked Articles

  • Digest
    Robin Spiller Magnus Simren