Table 1.

Regional Distribution of Small Intestinal Peyer's Patches

Mouse	Duodenum	Jejunum	Ileum
IL-7−/−	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 2	0, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3
iFABP-IL7	0, 0, 0, 0, 0	0, 1, 2, 2, 2	2, 2, 3, 3, 4
IL-7+/+	1, 1, 1, 1, 1 1, 1, 1, 1	2, 2, 2, 3, 4 4, 4, 5, 5	2, 2, 3, 3, 3 3, 4, 4, 4

Two-tailed unpaired Student's t tests were performed to compare the numbers of Peyer's patches in different regions of small intestine from 4–9-wk-old IL-7^−/−, iFABP-IL7, and age-matched IL-7^+/+ control mice.