Expression of IgH promoter/enhancer Ly-1 transgene in hematopoietic chimeric mice generated by embryonic stem cell line.
We have produced hematopoietic chimeric mice from an embryonic stem (ES) cell line carring Ly-1 cDNA under the control of IgH promoter and enhancer. Various amounts of serum IgM (5-86% of total IgM) in chimeric mice were of ES origin and 30-60% of IgM-positive B cells from the chimeric mice analyzed were reconstituted from ES cells. Using these chimeric mice, the expression of the Ly-1 transgene on lymphoid tissues was examined by polymerase chain reaction assay with primers specific for the transgene, and by cell sorter analysis. Transcription of the Ly-1 transgene was detected in spleen cells, thymocytes and lymph node cells; however, the expression of the Ly-1 molecule was observed only on lipopolysaccharide (LPS)-stimulated splenic IgM-positive B cells but not on resting splenic B cells. There was no significantly increased expression of Ly-1 on splenic T cells and thymocytes. Thus, our findings demonstrate that conventional splenic B cells could express the Ly-1 transgene on their surface in vivo after LPS stimulation. Also discussed is the ES-derived chimeric hematopoietic system.
Sumida
T
T
Second Department of Internal Medicine, School of Medicine, Chiba University, Japan.
Maeda
T
T
Koike
T
T
Tomioka
H
H
Yoshida
S
S
Taniguchi
M
M
Rajewsky
K
K
D000818:Animals; D000950:Antigens, Ly / Q000032:analysis / Q000235:genetics*; D001755:Blastocyst / Q000276:immunology; D002460:Cell Line; D002678:Chimera; D004247:DNA / Q000032:analysis; D004742:Enhancer Elements, Genetic; D005260:Female; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011247:Pregnancy; D011401:Promoter Regions, Genetic; D014162:Transfection
D000950:Antigens, Ly; D007143:Immunoglobulin Heavy Chains; D004247:DNA