What determines arthritogenicity of bacterial cell wall? A study on Eubacterium cell wall-induced arthritis

Rheumatology (Oxford). 2000 Mar;39(3):274-82. doi: 10.1093/rheumatology/39.3.274.

Abstract

Objective: To study what determines the arthritogenicity of the bacterial cell wall (CW) using Eubacterium CW-induced arthritis in the rat.

Methods: Eubacterium aerofaciens, previously reported as arthritogenic, and E. limosum and E. alactolyticum, known as non-arthritogenic, were used. Gas chromatography-mass spectrometry (GC-MS) was applied to analyse the chemical composition of the bacterial cell wall. Cellular immune response was measured by concanavalin A (Con A) stimulation and FACScan analysis. Also, serum antibodies against the injected cell wall were determined.

Results: Unexpectedly, from the two strains of E. aerofaciens used only one proved to be arthritogenic (with a CW inducing chronic arthritis after a single intraperitoneal injection), even though these two strains were 100% identical by 16S rDNA analysis. CW of the other E. aerofaciens strain induced only transient acute arthritis; CW of E. limosum and E. alactolyticum induced weak signs of acute arthritis. Based on the GC-MS analysis and on the results published previously, putative structures of peptidoglycan (PG) in the four CW preparations are presented. It is apparent that the presence of lysine in position 3 of the PG stem peptide contributes to arthritogenicity but is alone not decisive. Both strains of E. aerofaciens were immunosuppressive, when tested by Con A response at 2 weeks after CW injection. Such an immunosuppression was not observed after injection of CW from E. limosum or E. alactolyticum. FACScan analysis for six T cell markers and studies on serum antibody responses did not reveal any differences in the effect of the four bacterial strains used.

Conclusions: The results obtained suggest that the chemical structure of PG present in the bacterial CW is decisive in determining arthritogenicity/non-arthritogenicity. Therefore, from two bacterial strains belonging to normal human intestinal flora and 100% identical by 16S rDNA analysis, one proved to be arthritogenic and the other non-arthritogenic.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Animals
  • Arthritis, Reactive / immunology*
  • Arthritis, Reactive / microbiology
  • Cell Wall / chemistry
  • Cell Wall / immunology
  • Chronic Disease
  • Epitopes / immunology
  • Eubacterium / classification
  • Eubacterium / immunology*
  • Female
  • Flow Cytometry
  • Gas Chromatography-Mass Spectrometry
  • Humans
  • Lymphocyte Activation
  • Peptidoglycan / chemistry
  • Peptidoglycan / immunology*
  • Rats
  • Rats, Inbred Lew

Substances

  • Epitopes
  • Peptidoglycan