IgA1 & IgA2 distribution in the intestine

Abstract

The distribution of IgA1- and IgA2-containing cells was studied in 27 normal specimens taken from 3 parts of the intestine: the upper jejunum (8), the terminal ileum (5), and the large bowel (14). IgA1- and IgA2-containing cells were identified by an immunoperoxidase staining using mouse anti-IgA1 or IgA2 monoclonal antibody. The sum of IgA1-containing cells (IgA1+) and IgA2-containing cells (IgA2+) was greatest in the large bowel and least in the terminal ileum. IgA1+ were most frequent in the jejunum and least in the terminal ileum while IgA2+ were most frequent in the large bowel and least in the jejunum (p less than 0.005). The ratio of IgA1+/IgA2+ was 1.63 +/- 0.41 in the jejunum which was significantly higher than 0.65 +/- 0.46 in the terminal ileum (p less than 0.05) and 0.63 +/- 0.2 in the large bowel (p less than 0.001). These results lead to the new recognition that there is a shift in preponderance of IgA subclasses in the intestine, namely IgA1+ cells predominate in the jejunum and IgA2+ cells predominate in the intestine distal to the terminal ileum.

Longevity, clonal relationship and transcriptional program of celiac disease-specific plasma cells

“…64 The preferential usage of IgA1 over IgA2 that we observed in PCs of the controls was already wellestablished. 50 Beyond this known preference, we observed a further skewed IgA1/IgA2 usage in TG2specific PCs compared to PCs of unknown specificity in line with a previous report from our group. 22 While many clone groups contained only IgA1-or IgA2-expressing PCs, we also observed several clones spanning IgA1, IgA2 and even IgM.…”

“…It has long been known that IgA1 is preferentially used over IgA2 in the upper small intestine. 50 When looking at isotype usage in the controls, we observed this preferred usage of IgA1 (Fig. 9C).…”

Human IgA binds a diverse array of commensal bacteria

“…Whereas IgA1 is predominant in serum, IgA2 is mainly secreted in mucosal compartments (Chiba et al, 1987;Pakkanen et al, 2010). The abundance of the two IgA isotypes varies throughout the intestine (Chiba et al, 1987;Pakkanen et al, 2010). Peyer's patches contain more IgA1 + B cells than lamina propria, whereas, in contrast, colon contains mainly B cells that secrete IgA2, a subclass endowed with enhanced resistance to the action of bacterial proteases, as compared with IgA1 (He et al, 2007).…”

Long-Term Behavior of Secretory Immunity in Ileocecal and Ileal Orthotopic Neobladders

“…This finding does not exactly concur with data published by Murray et al [14] who found a significantly higher excretion of IgA in their series in the cecocystoplasties than in the ileal conduit or in ileocystoplasties. More cecum IgA production is supported by the anatomical finding that lymphoid tissue from the GALT system is particularly abundant in the distal part of the gastrointestinal tract [15][16][17]. In our ileocecourethrostomies immunoglobulins could be produced directly from the cecal mucosa or from the fragment of ileum and/or islands of residual lymphatic tissue remaining after appendicectomy.…”