Down-regulation of interleukin-8 secretion from Mycobacterium tuberculosis-infected monocytes by interleukin-4 and -10 but not by interleukin-13

Infect Immun. 2001 Apr;69(4):2470-6. doi: 10.1128/IAI.69.4.2470-2476.2001.

Abstract

Interleukin-8 (IL-8), a CXC chemokine, has a central role in leukocyte recruitment to areas of granuloma formation in tuberculosis. In the present studies, we investigated the effect of the T(H)2-derived cytokines IL-4, IL-10, and IL-13 on Mycobacterium tuberculosis-induced IL-8 secretion from purified human monocytes. Our results demonstrate that IL-4 and IL-10 have a down-regulatory effect on IL-8 secretion and that this effect is dose dependent. IL-10 has a greater effect than IL-4 on secretion, and autologous IL-10 secreted from M. tuberculosis-infected monocytes also down-regulates IL-8 secretion. The down-regulatory effect is partly a result of reduced IL-8 mRNA accumulation analyzed by reverse transcription-PCR. When combined, 1 microM IL-4 and IL-10 had an additive effect in decreasing IL-8 secretion and transcription; there was no synergy of action. IL-13 did not have any significant effect on IL-8 gene expression or secretion. The inhibitory effect of IL-10 but not of IL-4 is associated with decreased nuclear binding of the key activating transcription factor NF-kappaB. We show for the first time that M. tuberculosis causes up-regulation of nuclear binding of Oct-1 detected by electromobility gel shift assay. However, neither AP-1 nor Oct-1 nuclear binding was altered by IL-4 or IL-10. In summary, this study demonstrates that type 2 responses have an important role in the regulation of M. tuberculosis-induced IL-8 expression but that the mechanisms by which the different cytokines act are distinct.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / metabolism
  • DNA-Binding Proteins / metabolism
  • Down-Regulation
  • Host Cell Factor C1
  • Humans
  • Interleukin-10 / pharmacology*
  • Interleukin-13 / pharmacology*
  • Interleukin-4 / pharmacology*
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism*
  • Monocytes / metabolism*
  • Monocytes / microbiology
  • Mycobacterium tuberculosis / immunology*
  • NF-kappa B / metabolism
  • Octamer Transcription Factor-1
  • RNA, Messenger / analysis
  • Transcription Factor AP-1 / metabolism
  • Transcription Factors / metabolism

Substances

  • DNA-Binding Proteins
  • HCFC1 protein, human
  • Host Cell Factor C1
  • Interleukin-13
  • Interleukin-8
  • NF-kappa B
  • Octamer Transcription Factor-1
  • POU2F1 protein, human
  • RNA, Messenger
  • Transcription Factor AP-1
  • Transcription Factors
  • Interleukin-10
  • Interleukin-4
  • DNA