Evidence for phenotypic heterogeneity among B cells emigrating from the bursa of fabricius: a reflection of functional diversity?

Abstract

The bursa of Fabricius is a primary lymphoid organ with a central role in the establishment of the chicken B cell compartment (for review see Ratcliffe 1989a). The bursa is organized as folds of tissue containing about 104 discrete follicles surrounding a central lumen. Each follicle is divided into an outer cortex and an inner medulla, separated by a complex nucleated cortico-medullary boundary. The bursal lumen is connected by the bursal duct to the large intestine and gut-derived antigens in the chicken rectum can be transported into the bursal lumen (Sovari and Sovari 1977). Indeed, since the terminal portion of the chicken large intestine is capable of reverse peristaltic contractions, this transport can also result in the bursal lumen containing a variety of external antigens.