Background and aims: Interleukin-10 is an anti-inflammatory and immunomodulatory cytokine. Interleukin-10 deficient mice are prone to develop chronic colitis. Administration of recombinant human interleukin-10 has been proposed to have a beneficial effect in a subgroup of patients with Crohn's disease. Recently, we found an interleukin-10 Gly15Arg mutation in a family with Crohn's disease which is associated with reduced interleukin-10 secretion by in vitro stimulated monocytes and lymphocytes. We hypothesised that this interleukin-10 mutation plays a role in maintaining the inflammatory process in Crohn's disease in some families.
Patients and methods: We evaluated interleukin-10 Gly15Arg in 379 patients with Crohn's disease, and 75 unrelated healthy controls. Also, first degree family members of interleukin-10 Gly15Arg carriers were evaluated. Additionally, mutation carriers and their relatives were evaluated for CARD15 R702W, G908R, and 1007fs.
Results: Two patients with Crohn's disease were heterozygous for the interleukin-10 Gly15Arg mutation. No homozygotes were found. The Gly15Arg mutation was not observed in the controls. In first degree family members of the Crohn's disease-affected interleukin-10 Gly15Arg carriers, the mutation was found in Crohn's disease-affected as well as in their apparently healthy individuals. All family members carried one or two CARD15 mutation(s).
Conclusion: The interleukin-10 Gly15Arg mutation is rare in patients with Crohn's disease, and is not associated with the disease in the Netherlands.