Dependence of antibody somatic diversification on gut-associated lymphoid tissue in rabbits.
By approximately 4 to 8 wk of age, the IgH VDJ genes of essentially all rabbit B lymphocytes have undergone somatic diversification. Some of this diversification occurs in the appendix, which is a gut-associated lymphoid tissue (GALT). To determine whether GALT is essential for somatic diversification, we surgically removed the appendix, sacculus rotundus, and Peyer's patches from neonatal rabbits (designated GALT-less) and examined the extent to which VDJ genes were somatically diversified. We found that the IgM VDJ genes of peripheral B cells from 2- to 5-mo-old GALT-less rabbits had undergone considerably less somatic diversification than those of control rabbits. Further, the percentage of peripheral B cells in the GALT-less rabbits was generally less than that of controls. Our data suggest that, in rabbits, the primary Ab repertoire develops in GALT, and B cell expansion also occurs there. Hence, GALT may function as a mammalian bursal homologue.
Vajdy
M
M
Loyola University Chicago, Stritch School of Medicine, Department of Microbiology and Immunology, Maywood, IL 60153, USA.
Sethupathi
P
P
Knight
K L
KL
D000818:Animals; D000916:Antibody Diversity; D001402:B-Lymphocytes / Q000502:physiology; D001483:Base Sequence; D005803:Genes, Immunoglobulin; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007075:Immunoglobulin M / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000235:genetics; D007422:Intestines / Q000276:immunology*; D008221:Lymphoid Tissue / Q000502:physiology*; D008969:Molecular Sequence Data; D011817:Rabbits
D007143:Immunoglobulin Heavy Chains; D007075:Immunoglobulin M; D007135:Immunoglobulin Variable Region