B cells are selectively associated with thymic cortical but not medullary pathology in NZB mice.
Abnormal expansion of autoantibody-synthesizing B cells and self-reactive T cells, which most likely escape negative selection within the thymus, have both been characterized and reasoned to play a role in the pathogenesis of autoimmunity in NZB mice. Support for this thesis has been our observation that NZB mice have severe cortical and medullary thymic microarchitectural defects. As a means to dissect the roles of T and B cells in the induction of such abnormalities, B cell-deficient NZB mice were bred by backcrossing the Igh6(null)allele on to the NZB background (NZB-muMT mice). Such mice showed undetectable levels of autoantibodies. NZB-muMT mice, as compared to wild-type NZB mice, had lower absolute numbers of CD4(+)T cells. Furthermore, thymic abnormalities in NZB-muMT mice were restricted to the medulla. These data suggest that, while B cells may play a role in thymic cortical abnormalities, the medullary abnormalities are induced by other mechanisms.
Taguchi
N
N
Institute of Bio-Active Science, Nippon Zoki Pharmaceutical Co., Ltd, Kinashi, Yashiro-Cho, Kato-gun, Hyogo, 673-1461, Japan.
Hashimoto
Y
Y
Hsu
T
T
Ansari
A A
AA
Shultz
L
L
Dorshkind
K
K
Ikehara
S
S
Naiki
M
M
Gershwin
M E
ME
D000818:Animals; D001323:Autoantibodies / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D005260:Female; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D013950:Thymus Gland / Q000276:immunology / Q000473:pathology*
D001323:Autoantibodies