Peptidergic innervation of the Bursa Fabricii: interrelation with T-lymphocyte subsets.
In birds, B-lymphocytes mature in a special immune organ, the Bursa Fabricii. This organ thus offers unique possibilities for the study of the microenvironment of B-lymphocyte differentiation. We previously reported tachykinin-, vasoactive intestinal peptide-, calcitonin gene-related peptide- and galanin-immunoreactive (ir) fibres in the chicken bursa. As judged from light microscopic studies, each of the peptides was found in fibres contacting B-lymphocytes. Vasoactive intestinal peptide-ir fibres contacted macrophages. Now, we demonstrate neuropeptide Y, indicating the sympathetic nervous system, in fibres associated with arteries, not entering the follicles. CD4- and CD8-positive T-lymphocytes were dispersed in bursal follicles and the connective tissue, most densely in subepithelial regions. We could not find close apposition of fibres with either T-cell subset. We conclude that the potential neuro-immune axis in the Bursa Fabricii may represent a neuro-B-cell-link with only indirect participation of T-lymphocytes. The sympathetic input may influence the bursal microenvironment primarily by regulating the blood supply.
Zentel
H J
HJ
Institute for Anatomy, Joh. Gutenberg-Univ., Mainz, FRG.
Nohr
D
D
Albrecht
R
R
Jeurissen
S H
SH
Vainio
O
O
Weihe
E
E
D000818:Animals; D000911:Antibodies, Monoclonal; D002060:Bursa of Fabricius / Q000276:immunology*; D015704:CD4 Antigens / Q000276:immunology; D016827:CD8 Antigens / Q000276:immunology; D002645:Chickens; D005724:Ganglia / Q000378:metabolism; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D008832:Microchemistry; D009478:Neuropeptide Y / Q000276:immunology; D009479:Neuropeptides / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D016827:CD8 Antigens; D009478:Neuropeptide Y; D009479:Neuropeptides