Investigation of primary immune deficiency associated with LRBA (LPS-responsive beige-like anchor) deficiency in adult patients with diagnosed with inflammatory bowel disease and celiac disease

In the present study, it was aimed to investigate the presence of the primary immunodeficiency disorder associated with LRBA deficiency in adult patients followed-up with diagnosis of inflammatory bowel disease (IBD) and celiac disease (CD). For this purpose, CTLA-4 and LRBA protein expression levels of activated peripheral blood CD4+CD25highCD127low/-FoxP3+ Treg cells belonging to 35 patients (CD= 11 and IBD = 24) and 13 healthy controls, were evaluated by flow cytometric analysis. According to comparison between healthy controls and sick individuals; Treg percentages were found to have lower levels in the patient group (controls: 5.8%, sick individuals: 5.1%; p = 0.19), especially in IBD group (IBD: 4.5%, CD: 5.2%). Median FI levels for CTLA-4 and LRBA expression were compared to healthy controls in each experiment by applying the correction ratio; low levels of LRBA expression was determined in 12 (50%) of the patients with IBD. According to scatter-plot graph of all individuals for CTLA-4 and LRBA expressions; there was a linear correlation between the flow-cytometric expression of the two molecules. A new heterozygous-inherited genetic variant in the LRBA gene was detected in one among 4 individuals (which have low LRBA expression) at the primary immunodeficiency panel via next generation sequencing analysis. These results illuminate the some factors or changes associated with the immune-related enteropathy of the intestinal system, which is considered to be the largest secondary lymphoid organ. Findings should be evaluated in the other patients have low-expression for LRBA (and maybe in another larger cohort). It is considered that it may provide useful data in terms of diagnosis, etiology and treatment course of the immune-related enteropathy, especially IBD.