The jejunum and ileum of 5 day old and adult normal pigs and of 45 day old germ free pigs were used to study the lymphocyte pools in the epithelium and lamina propria by sequential treatments with EDTA, four hours, and 12 hours of collagenase treatment. In adult animals the incubation of the jejunal wall with EDTA resulted in mean (SD) 26.8 (10.9) x 10(6) intraepithelial lymphocytes per g of ti...

The protein tyrosine phosphatase CD45 has been shown to be an important regulator of antigen-receptor signaling in both T and B lymphocytes. Lymphocyte populations within the gut mucosa are phenotypically and ontogenetically different from those generally found in secondary lymphoid tissue. In T lymphopenic mice, extrathymic T cell development takes place within the gut. Here we report the char...

Gut-associated lymphocytes were described in fish, but their involvement in immune responses is still unknown. In rainbow trout, intraepithelial lymphocytes (IELs) are scattered between gut epithelial cells, but neither Peyer's patches nor mesenteric lymph nodes were identified. Rainbow trout IELs contain mainly T cells, because they expressed transcripts of T cell marker homologs of CD8, CD4, ...

The Ly49 NK receptor family in mice is composed of several members that recognize MHC class I (MHC-I) or MHC-I-related molecules. We and others have shown before that Ly49E is a unique member, with a different expression pattern on NK cells and being triggered by the non-MHC-I-related protein urokinase plasminogen activator. Among the entire Ly49 receptor family, Ly49E is the only Ly49 member e...

The upper digestive tract is routinely scoped for several causes of malabsorption, and the number of duodenal biopsy specimens has increased notably in the last 10 years. Gluten-sensitive enteropathy (GSE) is an autoimmune disease, which shows an increasing prevalence worldwide and requires a joint clinico-pathological approach. The classical histopathology of GSE with partial or total villous ...

To identify interleukin-10 (IL-10)-producing cells in vivo, we generated a knockin mouse where an internal ribosome entry site (IRES) green fluorescence protein (GFP) element was inserted immediately before the polyadenylation site of the IL-10 gene. GFP fluorescence in cells from these mice was found to correlate positively with IL-10 protein expression. With this model, we found that after mu...