NON-RANDOM DISTRIBUTION OF INTRAEPITHELIAL LYMPHOID-CELLS IN FOLLICLE-ASSOCIATED EPITHELIUM OF PEYERS PATCHES IN MICE

The spatial distribution of intraepithelial lymphoid cells in follicle-associated and villus epithelium Peyer''s patches were studied quantitatively in Balb/C and CFW/L1 mice. The distribution of the number of lymphoid cells per segmental length, equal to an average width of an epithelial cell, of dome epithelium was non-random, since it deviated significantly from the theoretical Poisson distribution. Some segments of the dome epithelium are lymphocyte-rich and some are lymphocyte-depleted. It was also demonstrated that segments rich in lymphocytes occurred in series or clusters. This was in contrast to the distribution in the epithelial layer of the villi, in which the distribution of the number of lymphoid cells per segment followed the Poisson distribution. The results were essentially the same for Balb/C and CFW/L1 mice. Clustering of lymphoid cells within the follicle-associated epithelium, previously suggested and now established by objective histometric and statistical procedures, awaits further studies of its biological significance.