The mammalian equivalent to bursa fabricii of birds

A Qualitative and Quantitative Morphologic Study of Peyer's Patches of the Mouse

“…In mammals, gut-associated lymphatic tissues such as the tonsil, appendix and Peyer's patches have been proposed by certain authors as being equivalent to the avian bursa of Fabricius which serves as the central lymphatic tissue (COOPER et al, 1966;FICHTELIUS, 1966;CRAIG and CEBRA 1975). In the mouse, Peyer's patches represent the major gut-associated lymphatic tissue, because the tonsil is lacking and the appendix is poorly developed, containing only few lymphatic nodules.…”

Intraepithelial lymphocytes of the small intestine.

“…Now, of course, it is known that lymphocytes leave the bloodstream to recirculate from blood to lymph in the lymphoid tissues15. In 1967 Fichtelius16 originated yet another theory of the functions of the intraepithelial lymphocytes which he called 'theliolymphocytes'. He had undertaken an extensive phylogenetic study of the lymphoepithelial organs17 and had found lymphocytes within the gut epithelium of all species studied. He proposed that the theliolymphocytes were a population of cells, still evolving in mammals as a 'bursa-equivalent', influencing and controlling 921 the maturation of B lymphocytes.…”

Fine Structure of the Dome in Peyer's Patches of Mice

“…In mammals which lack the bursa, gut-associated lymphatic tissues including the tonsil, Pever's patches and appendix have been considered as the possible bursa-equivalent (COOPER et al, 1966;FICHTELIUS, 1966;CRAIG and CEBRA, 1975). However, gut-associated lymphatic tissues are different from the central lymphatic tissue in that they serve as the site of antibody-production (COOPER and TURNER, 1967;MULLER-SCHOOP and GOOD, 1975) and that lymphopoiesis is dependent on antigenic stimulation (PEREY and GOOD, 1968).…”

“…Gut-associated lymphatic tissues such as Peyer's patches are also lympho-epithelial in nature, and the epithelial cells have been thought to exert the same influence on differentiation of lymphocytes as those of the avian bursa (COOPER et al, 1966, FICHTELIUS, 1966CRAIG and CEBRA, 1975). As reported in a previous paper (ABE and ITO, 1978), however, the epithelium over the dome of the Peyer's patch contains both T-and B-lymphocytes, and the proportions of intraepithelial T-and B-lymphocytes are similar to those in the total lymphocytes of the patch in which lymphocytes are mostly differentiated T-and B-lymphocytes as in the case of peripheral lymphatic tissues.…”