Characterisation of the LDL receptor in Epstein-Barr virus transformed lymphocytes.
Non-dividing human lymphocytes were transformed upon infection with the Epstein-Barr virus (EBV) into lymphoblasts which are capable of continuous growth in culture. We studied the properties of the LDL receptor in EBV-transformed human lymphocytes (EBV-L) by binding experiments and by ligand blotting. EBV-L show a high affinity binding of LDL in the same order of magnitude as found with fibroblasts; EBV-L obtained from a homozygous familial hypercholesterolemic (FH) patient fail to express LDL receptor activity. Similar to that of fibroblasts, the LDL receptor activity in EBV-L is Ca2(+)-dependent and is down-regulated by the presence of an exogenous source of cholesterol in the medium. The LDL receptor protein of EBV-L has an apparent molecular weight of 130,000. Since our results show that EBV-L display a LDL receptor protein similar to the LDL receptor present in fibroblasts, we conclude that in comparison with other cell types the EBV-L offer a suitable model system to investigate LDL receptor protein abnormalities in FH patients.
Lombardi
P
P
Gaubius Institute TNO, Leiden, The Netherlands.
de Wit
E
E
Frants
R R
RR
Havekes
L M
LM
D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism; D004854:Herpesvirus 4, Human / Q000502:physiology; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000378:metabolism; D007700:Kinetics; D008074:Lipoproteins / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000378:metabolism; D008079:Lipoproteins, VLDL / Q000378:metabolism; D008214:Lymphocytes / Q000378:metabolism* / Q000382:microbiology; D011489:Protein Denaturation; D011973:Receptors, LDL / Q000378:metabolism*
D008074:Lipoproteins; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; D011973:Receptors, LDL