Differential requirements of CD45 for lymphocyte development and function.
CD45 exon 6-deficient mice show a profound block of thymocyte development at a transitional differentiation step from immature CD4+ CD8+ to mature single-positive cells. Only a few T lymphocytes are observed in the periphery of such animals, but B cell development is not affected. We investigated whether mature B lymphocytes in CD45 exon 6-deficient mice have normal functions in the absence of CD45 expression and show here that CD45-defective B lymphocytes from CD45 exon 6-deficient mice have intact B lymphocyte functions, including T-dependent and T-independent antigen-specific antibody production and class switching in vivo if normal CD4+ T lymphocytes were adoptively transferred into the mutant mice. From these results, we conclude that CD45 expression on B lymphocytes is not essential for B cell responses following antigen stimulation in vivo. However, CD4+ T helper function was severely diminished in CD45 exon 6-deficient mice, suggesting that the requirements of CD45 molecules in antigen-specific response and development are different between T and B lymphocytes.
Kong
Y Y
YY
Department of Immunology, Kyushu University, Fukuoka, Japan.
Kishihara
K
K
Sumichika
H
H
Nakamura
T
T
Kaneko
M
M
Nomoto
K
K
D000818:Animals; D000921:Antibody-Producing Cells / Q000166:cytology; D001402:B-Lymphocytes / Q000145:classification / Q000166:cytology / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000637:transplantation; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D002455:Cell Division / Q000187:drug effects / Q000276:immunology; D000939:Epitopes; D016130:Immunophenotyping; D016219:Immunotherapy, Adoptive; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000502:physiology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout
D000939:Epitopes; D017493:Leukocyte Common Antigens