Impaired antigen receptor induced calcium mobilization in a phospholipase C-gamma1 deficient B cell line.
B lymphocytes express phospholipase C-gamma(1) (PLC-gamma(1)) and phospholipase C-gamma(2) (PLC-gamma(2)) isozymes. However, the relative importance of these two isozymes in B cell signaling is not known. We report here the identification and analysis of a B cell line deficient in PLC-gamma(1). Mature splenic B lymphocytes and a panel of cell lines representing pre-B, immature and mature B cell stages expressed phospholipase C-gamma (PLC-gamma), but not the beta or delta isoforms of phospholipase C (PLC). While all the tested B cell lines and primary splenic B cells expressed PLC-gamma(1) and PLC-gamma(2) isozymes, the L1.2 B cell line exclusively expressed PLC-gamma(2), but not PLC-gamma(1) isozyme. The PLC-gamma(1) deficient L1.2 B cells expressed levels of surface IgM comparable to that of PLC-gamma(1) positive 70Z/3 B cell line. However, stimulation through the antigen receptor induced Ca(++) response in 70Z/3, but not L1.2 B cells, suggesting a requirement for PLC-gamma(1) in antigen receptor induced Ca(++) signaling in these cells. The possible use for L1.2 cells in testing the regulation of PLC-gamma(1) and PLC-gamma(2) dependent calcium mobilization in B lymphocytes is discussed.
Muthusamy
Natarajan
N
Center for Molecular and Human Genetics, The Department of Pediatrics, Columbus Children's Research Institute, The Ohio State University Columbus, OH 43205, USA. rmuthusa@chi.osu.edu
Park
Do Joon
DJ
Rho
Hei-Won
HW
Rhee
Sue Goo
SG
Subbarao
Bondada
B
D000818:Animals; D001402:B-Lymphocytes / Q000201:enzymology* / Q000276:immunology* / Q000378:metabolism; D020013:Calcium Signaling; D045744:Cell Line, Tumor; D007075:Immunoglobulin M / Q000276:immunology / Q000378:metabolism; D051379:Mice; D051966:Phospholipase C gamma; D011947:Receptors, Antigen, B-Cell / Q000276:immunology / Q000378:metabolism*; D013997:Time Factors; D010738:Type C Phospholipases / Q000172:deficiency*
D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell; D010738:Type C Phospholipases; D051966:Phospholipase C gamma