ESTABLISHMENT AND CHARACTERIZATION OF AN EPSTEIN-BARR VIRUS-TRANSFORMED B-CELL LINE, KM C8, FROM A PATIENT WITH INFANTILE SIALIC-ACID STORAGE DISEASE (ISSD)/

Nakano et al. have recently reported a Japanese case of infantile sial ic acid storage disease [C. Nakano, Y. Hirabayashi, K. Ohno, T. Yano, T. Mito, M. Sakurai, Brain Dev., 18 (1996) 153-156]. For further etiol ogical analysis of this disease, we prepared the Epstein-Barr virus (E BV)-transformed cell line (LCL) from the peripheral lymphocytes of thi s patient and performed initial characterization of the cells. Electro n microscopy of the cells showed that the cells contained many vacuole s and swelled lysosomes. Cytochemical staining with sialic acid-specif ic lectin, Limax flavus agglutinin (LFA), showed strong staining on me mbranes and subcellular organelles on the patient-derived cells, where as LCL from a normal person was only weakly stained. The cells from th e patient contained 5.5-7.3 nmol/10(7) cells of free N-acetyl neuramin ic acid, whereas three strains of LCLs derived from normal persons con tained 1 nmol/10(7) cells. The culture supernatant of LCL from the pat ient contained 144 nmol/ml of free N-acetyl neuraminic acid, whereas t he LCL culture supernatant from normal persons contained 57-73 nmol/ml of free sialic acid, which was the same or only at a slightly higher level than the fresh medium. In addition, cellular acidic sialidase me asured as 4-methylumbelliferyl sialidase was elevated (10(7) nmol 4-me thylumbelliferon released/mg cellular protein/60 min). The EBV-LCL fro m an ISSD patient is considered to remain as the abnormality of the ce ll donor. (C) 1998 Elsevier Science B.V. All rights reserved.