title: 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.
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D003106:Colon / Q000166:cytology / Q000276:immunology; D005260:Female; D006801:Humans; D007082:Ileum / Q000166:cytology / Q000276:immunology; D007124:Immunoenzyme Techniques; D007070:Immunoglobulin A / Q000032:analysis*; D007413:Intestinal Mucosa / Q000276:immunology*; D007583:Jejunum / Q000166:cytology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012007:Rectum / Q000166:cytology / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D007070:Immunoglobulin A