Measurement of phosphatidylcholine transfer protein in rat liver and hepatomas by radioimmunoassay.
An antiserum was raised against the phosphatidylcholine transfer protein from rat liver by immunization of rabbits. The antiserum was shown to be specific for this protein. A double-antibody radioimmunoassay for the phosphatidylcholine transfer protein was developed. In order to economize the use of second antibody (immunobeads), the specific anti-phosphatidylcholine transfer protein-IgG fraction isolated by affinity chromatography was used. Phosphatidylcholine transfer protein was labelled with 125I by the glucose oxidase-lactoperoxidase method and purified from the reaction mixture by affinity chromatography. Approx. 80% of the tracer was immunoprecipitable. The operating range of the assay was from 4 to 50 ng of transfer protein. This assay was used to determine the levels of phosphatidylcholine transfer protein in the 105000 x g supernatant fractions of rat liver and Morris hepatomas 7777, 7787 and 9633. The values obtained for the tumors were in good agreement with results previously obtained by immunotitration of the phosphatidylcholine transfer activity (Poorthuis, B.J.H.M., Van der Krift, T.P., Teerlink, T., Akeroyd, R., Hostetler, K.Y. and Wirtz, K.W.A., Biochim. Biophys. Acta 600 (1980) 376--386). For normal and host liver, the values determined by the radioimmunoassay were 2--4-fold higher.
D000727:Androgen-Binding Protein; D000818:Animals; D002352:Carrier Proteins / Q000032:analysis*; D007074:Immunoglobulin G / Q000302:isolation & purification; D008099:Liver / Q000032:analysis*; D008114:Liver Neoplasms, Experimental / Q000032:analysis*; D008832:Microchemistry; D010713:Phosphatidylcholines / Q000032:analysis*; D049294:Phospholipid Transfer Proteins; D060789:Prostatein; D011863:Radioimmunoassay / Q000379:methods; D051381:Rats; D060765:Secretoglobins; D014598:Uteroglobin; D060788:Mammaglobin B
D000727:Androgen-Binding Protein; D002352:Carrier Proteins; D007074:Immunoglobulin G; D010713:Phosphatidylcholines; D049294:Phospholipid Transfer Proteins; D060789:Prostatein; D060765:Secretoglobins; D014598:Uteroglobin; C511484:Scgb1d2 protein, rat; C511483:Scgb1d4 protein, rat; C556468:Scgb2a1 protein, rat; D060788:Mammaglobin B