Antibodies against tumor necrosis factor (TNF) induce T-cell apoptosis in patients with inflammatory bowel diseases via TNF receptor 2 and intestinal CD14⁺ macrophages

Gastroenterology. 2011 Dec;141(6):2026-38. doi: 10.1053/j.gastro.2011.08.032. Epub 2011 Aug 27.

Abstract

Background & aims: The anti-tumor necrosis factor (TNF) antibodies infliximab, adalimumab, and certolizumab pegol have proven clinical efficacy in Crohn's disease. Here, we assessed the effects of anti-TNF antibodies on apoptosis in inflammatory bowel disease (IBD).

Methods: CD14(+) macrophages and CD4(+) T cells were isolated from peripheral blood and lamina propria mononuclear cells from patients with IBD and control patients. Cell surface markers and apoptosis were assessed by immunohistology and fluorescence-activated cell sorting techniques.

Results: Lamina propria CD14(+) macrophages showed significantly more frequent and higher membrane-bound TNF (mTNF) expression than CD4(+) T cells in IBD, whereas mTNF-dependent signaling proteins such as TNF receptor (TNFR) 2, TNFR-associated factor (TRAF) 2, and nuclear factor κB were induced in IBD mucosal CD4(+) T cells. Most anti-TNF antibodies did not induce T-cell apoptosis in purified peripheral or mucosal CD4(+) T cells. However, in contrast to etanercept, administration of all clinically effective anti-TNF antibodies resulted in a significant induction of T-cell apoptosis in IBD when lamina propria CD4(+) T cells expressing TNFR2(+) were cocultured with mTNF(+) CD14(+) intestinal macrophages. In contrast, no effects in control patients were noted. T-cell apoptosis in IBD occurred in vivo after treatment with adalimumab and infliximab, was critically dependent on TNFR2 signaling, and could be prevented via interleukin-6 signal transduction. Blockade of interleukin-6R signaling augmented anti-TNF-induced T-cell apoptosis in IBD.

Conclusions: Clinically effective anti-TNF antibodies are able to induce T-cell apoptosis in IBD only when mucosal TNFR2(+) T cells are cocultured with mTNF-expressing CD14(+) macrophages. The finding that anti-TNF antibodies induce apoptosis indirectly by targeting the mTNF/TNFR2 pathway may have important implications for the development of new therapeutic strategies in IBD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adalimumab
  • Aged
  • Anti-Inflammatory Agents / pharmacology*
  • Antibodies, Monoclonal / pharmacology
  • Antibodies, Monoclonal, Humanized / pharmacology
  • Apoptosis / drug effects*
  • CD4-Positive T-Lymphocytes / metabolism
  • CD4-Positive T-Lymphocytes / pathology*
  • Case-Control Studies
  • Certolizumab Pegol
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Flow Cytometry
  • Humans
  • Immunoglobulin Fab Fragments / pharmacology
  • Inflammatory Bowel Diseases / immunology
  • Inflammatory Bowel Diseases / pathology*
  • Infliximab
  • Lipopolysaccharide Receptors / metabolism
  • Macrophages / immunology*
  • Male
  • Middle Aged
  • Polyethylene Glycols / pharmacology
  • Real-Time Polymerase Chain Reaction
  • Receptors, Tumor Necrosis Factor, Type II / metabolism*
  • Tumor Necrosis Factor-alpha / immunology*
  • Young Adult

Substances

  • Anti-Inflammatory Agents
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Immunoglobulin Fab Fragments
  • Lipopolysaccharide Receptors
  • Receptors, Tumor Necrosis Factor, Type II
  • Tumor Necrosis Factor-alpha
  • Polyethylene Glycols
  • Infliximab
  • Adalimumab
  • Certolizumab Pegol