Lectin-reactive Anti-α-Gal in Patients with Crohnʼs Disease

Abstract

Background Patients with inflammatory bowel disease have higher proportions of immunoglobulin G (IgG) antibodies lacking N-galactose, also called agalactosyl IgG, in their serum. Such agalactosyl IgGs have been associated with disease activity and the immunogenicity of biologics. The aim was to describe the relationship between circulating levels of a subset of agalactosyl IgGs (anti-α-Gal) and Crohn’s disease (CD) phenotypes. Methods Prospectively collected serum samples of a well-characterized cohort of patients with inflammatory bowel disease and controls were used. Serum anti-α-Gal levels were measured by a high-affinity enzyme-linked immunosorbent assay and referenced to a standard control. Results Serum samples from 167 subjects were tested; 62 with CD, 76 with ulcerative colitis, and 29 controls. Agalactosyl anti-α-Gal levels were significantly higher in active CD than in active ulcerative colitis (P = 0.0043) or healthy controls (P < 0.0001). Among patients with CD, agalactosyl anti-α-Gal levels were significantly higher in those with a history of arthritis, than those without (P = 0.0002), but lower in those taking immunomodulators (P = 0.03). There was no correlation between agalactosyl anti-α-Gal levels and indices of Crohn’s severity, including C-reactive protein levels or Harvey– Bradshaw index. Patients who were primary or secondary nonresponders to infliximab had similar agalactosyl anti-α-Gal levels to clinical responders. Conclusions Patients with CD have greater amounts of agalactosylated anti-α-Gal antibodies in their serum, particularly in those with associated joint disease. This increase seems to be independent of indices of disease activity, but is influenced by immunomodulator use.

Altered Blood Levels of Anti-Gal Antibodies in Alzheimer’s Disease: A New Clue to Pathogenesis?

“…Thirty sex/age-matched cognitively healthy subjects (HS) were recruited as the control group. Since anti-Gal antibody levels can be altered in the context of different pathologies and treatments, subjects with pathologies, such as rheumatoid arthritis, interstitial cystitis, eosinophilic esophagitis [23], Henoch-Schönlein purpura, IgA nephropathy, Crohn's disease and ulcerative colitis [24], or treated with anticancer such as Cetuximab (or Erbitux) [25], animal derived tissue patches, cartilaginous grafts or bioprostheses such as biological heart valves [26], were excluded. The clinical and demographic characteristics of the two groups of participants are summarized in Table 1.…”