Spontaneous cytotoxicity against measles virus infected and K562 cells in normal subjects and subacute sclerosing panencephalitis.

Spontaneous cytotoxicity towards LU106 (heteroploid human lung cell line) cells persistently and acutely infected with measles virus was studied in measles immune and nonimmune healthy subjects and SSPE patients. K562 (myeloid cell line) cells were also used to detect the NK activity. Specific cytotoxic responses for measles immune and nonimmune donors were not significantly different for both persistently and acutely measles infected LU106 cells indicating that our assay system detected NK activity. Cytotoxic responses of SSPE patients against virus infected and K562 cells were found to be within normal limits in 3 and 5 patients respectively.