Germinal Centers in the Tonsilla Caecalis — Relationship to the Thymus and the Bursa of Fabricius

Abstract

It is generally accepted that the thymus and the bursa of Fabricius are principal organs of the chicken’s lymphoid system and immune potential. While neonatal thymectomy influences delayed hypersensitivity responses (Warner et al., 1962; Janković and Išvaneski, 1963; Jankovic et al., 1965), the extirpation of the bursa at hatching affects antibody production (Click et al., 1956; Mueller et al., 1960). Evidence forthcoming from several laboratories (Szenberg and Warner, 1962; Janković and Išvaneski, 1963; Cooper et al., 1965), suggested a dissociation of thymus-dependent and bursa-dependent lymphoid tissue. Correspondingly, the population of small lymphocytes of the splenic white pulp is influenced by the thymus, whereas the number of plasmacellular elements and germinal centers is governed by the functioning of the bursa. In a previous paper (Janković et al., 1966), we pointed out the immunological function of the tonsilla caecalis (Basslinger, 1858). The present communication provides data on the correlation between the bursa of Fabricius and the germinal centers in the caecal tonsil and Peyer’s patches.

Supported by grants from the Federal Scientific Fund, Belgrade.