Kuo S, El Guindy A, Panwala C M, Hagan P M, Camerini V
Department of Pediatrics, Division of Neonatology, University of Virginia Health Sciences Center, Charlottesville, VA 22908, U.S.A.
Pediatr Res. 2001 Apr;49(4):543-51. doi: 10.1203/00006450-200104000-00017.
We examined the appearance of intestinal intraepithelial lymphocytes (IEL) during the first 12 wk of life to gain insight into postnatal factors that contribute to the differences found between IEL in the large and small intestines of adult mice. Intestinal T cells were very infrequent at birth, but increased in number in the large and small intestine during the first 4 wk of life and then stabilized. The small intestinal epithelium at 2 wk of age contained mostly T cell receptor (TCR) alphabeta+, CD2+ T cells, unlike IEL in adult mice, which were composed of nearly equal proportions of CD2-, TCR alphabeta+ and TCR gammadelta+ cells. Between 2 and 3 wk of age, TCR gammadelta+, CD2- IEL increased greatly in the small intestine, whereas TCR alphabeta+ cells expressing CD2 decreased. By contrast, IEL in the large intestine at 2 and 3 wk of age were mostly TCR alphabeta+, CD2+ T cells similar to large intestinal IEL in adult mice. And finally, the expression of CD69 increased earlier and to higher levels on TCR alphabeta+ and TCR gammadelta+ IEL in the small intestine than in the large intestine. Our results demonstrate that IEL in the large and small intestine are phenotypically similar during suckling and that differences between these populations are established after weaning. Furthermore, the earlier accumulation of IEL with an activated adult IEL phenotype in the small intestine suggests that these T cells mature or expand in the gut and contribute to the maturation of immune function during postnatal life in mice.
我们研究了出生后前12周内肠道上皮内淋巴细胞（IEL）的表现，以深入了解导致成年小鼠大肠和小肠IEL之间差异的出生后因素。肠道T细胞在出生时非常罕见，但在出生后的前4周内，大肠和小肠中的数量增加，然后稳定下来。与成年小鼠的IEL不同，成年小鼠的IEL由几乎相等比例的CD2-、TCRαβ+和TCRγδ+细胞组成，2周龄时小肠上皮主要包含T细胞受体（TCR）αβ+、CD2+ T细胞。在2至3周龄之间，小肠中TCRγδ+、CD2- IEL大幅增加，而表达CD2的TCRαβ+细胞减少。相比之下，2周龄和3周龄时大肠中的IEL大多是TCRαβ+、CD2+ T细胞，类似于成年小鼠大肠中的IEL。最后，小肠中TCRαβ+和TCRγδ+ IEL上CD69的表达比大肠中更早且更高。我们的结果表明，在哺乳期间，大肠和小肠中的IEL在表型上相似，并且这些群体之间的差异在断奶后形成。此外，小肠中具有活化成年IEL表型的IEL的早期积累表明，这些T细胞在肠道中成熟或扩增，并有助于小鼠出生后免疫功能的成熟。
