The effects of the microbiome on the B cell receptor repertoire in patients with Ulcerative Colitis
Prof. Ken Smith
Institution or company
University of Cambridge
We wish to examine the B cell receptor (BCR) repertoire in patients with Ulcerative Colitis. B cells play an integral role in immunity, with the key role of producing antibodies. Each B cell expresses a BCR. The BCR is an antibody that is bound to the cell surface and is generated through genetic recombination. This results in a large number of unique BCRs for a given individual, termed “repertoire”. To prevent auto-antibodies from attacking self, auto-reactive B cells are removed or further genetic recombination of the BCR is initiated. If unsuccessful, this can lead to auto-immunity. We have developed a novel method where we can study the BCR repertoire for a given individual. In our recent publication, we found striking abnormalities in Crohn’s disease, suggestive of involvement of gut mucosal immunity and abnormalities in the gut microbiome (Bashford-Rogers et al. Nature, 2019). We wish to extend our analysis to Ulcerative Colitis, studying the BCR repertoire at the time of active disease, post treatment and during disease remission. In addition, studying Ulcerative Colitis gives us the unique opportunity to study the effects of the microbiome on the BCR repertoire by comparing the repertoire pre and post colectomy. Reference Bashford-Rogers, R. J. M. et al. Analysis of the B cell receptor repertoire in six immune-mediated diseases. Nature 574, 122–126 (2019).