Development of B cells secreting endogenous or transgene-encoded immunoglobulins in H-chain transgenic mice.
The development of splenic B cells secreting transgene-encoded or endogenous immunoglobulin (Ig) was analysed in the mu heavy (H-)chain transgenic mouse line M54. The results show that cells secreting endogenous Ig are not detectable during the perinatal period, even after lipopolysaccharide stimulation in vitro. At this time, transgene-secreting cells are readily detectable and keep increasing with age of the animals. After a few weeks of age cells secreting endogenous Ig appear in the spleen and keep increasing with age, reaching numbers comparable to non-transgenic littermates by 5 weeks of age. Thereafter, the proportion of transgene-secreting B cells decreases. We conclude that the preferential expression of endogenous Igs by secreting B cells in the adult does not result from peculiar genetic features of those cells, but from age-dependent cellular selection operating on all B cells.
Grandien
A
A
Department of Immunology, BMC, University of Uppsala, Sweden.
Coutinho
A
A
Andersson
J
J
D000367:Age Factors; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007075:Immunoglobulin M / Q000235:genetics*; D007136:Immunoglobulins / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic
D007143:Immunoglobulin Heavy Chains; D007075:Immunoglobulin M; D007136:Immunoglobulins; D008070:Lipopolysaccharides