Distinct patterns of IgG and IgA against food and microbial antigens in serum and feces of patients with inflammatory bowel diseases

PLoS One. 2014 Sep 12;9(9):e106750. doi: 10.1371/journal.pone.0106750. eCollection 2014.


Background: Inflammatory bowel disease (IBD) is associated with a defective intestinal barrier and enhanced adaptive immune responses against commensal microbiota. Immune responses against food antigens in IBD patients remain poorly defined.

Methods: IgG and IgA specific for food and microfloral antigens (wheat and milk extracts; purified ovalbumin; Escherichia coli and Bacteroides fragilis lysates; mannan from Saccharomyces cerevisiae) were analyzed by ELISA in the serum and feces of patients with Crohn's disease (CD; n = 52 for serum and n = 20 for feces), ulcerative colitis (UC; n = 29; n = 17), acute gastroenteritis/colitis (AGE; n = 12; n = 9) as well as non-inflammatory controls (n = 61; n = 39).

Results: Serum anti-Saccharomyces cerevisiae antibodies (ASCA) and anti-B. fragilis IgG and IgA levels were increased in CD patients whereas antibody (Ab) levels against E. coli and food antigens were not significantly different within the patient groups and controls. Subgroup analysis revealed that CD patients with severe diseases defined by stricturing and penetrating lesions have slightly higher anti-food and anti-microbial IgA levels whereas CD and UC patients with arthropathy have decreased anti-food IgG levels. Treatment with anti-TNF-α Abs in CD patients was associated with significantly decreased ASCA IgG and IgA and anti-E. coli IgG. In the feces specific IgG levels against all antigens were higher in CD and AGE patients while specific IgA levels were higher in non-IBD patients. Anti-food IgG and IgA levels did not correlate with food intolerance.

Summary: In contrast to anti-microbial Abs, we found only minor changes in serum anti-food Ab levels in specific subgroups of IBD patients. Fecal Ab levels towards microbial and food antigens show distinct patterns in controls, CD and UC patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens / immunology*
  • Case-Control Studies
  • Crohn Disease / blood
  • Crohn Disease / immunology
  • Feces / microbiology*
  • Food*
  • Humans
  • Immunoglobulin A / blood*
  • Immunoglobulin G / blood*
  • Inflammatory Bowel Diseases / blood
  • Inflammatory Bowel Diseases / immunology*
  • Inflammatory Bowel Diseases / microbiology
  • Serum / microbiology*
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors
  • Tumor Necrosis Factor-alpha / metabolism


  • Antigens
  • Immunoglobulin A
  • Immunoglobulin G
  • Tumor Necrosis Factor-alpha

Grants and funding

The research leading to these results has received funding from the German Research Foundation (DFG SE 1122/1) and the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n°305564 (SysmedIBD). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.