Activated sialidase activity in transformed lymphocytes by Epstein-Barr (EB) virus of sialidosis type I (cherry-red spot-myoclonus syndrome).

We report a new Japanese family of sialidosis type I. The sialidase activity was deficient in the lymphocytes of 2 patients (6.8% (sister) and 12.5% (brother) of control mean). However, surprisingly, using the transformed lymphocytes by EB virus, this activity was activated to 51.7% (sister) and 49.5% (brother) of control mean, respectively. Although the mechanism for this activation was not known, we discussed the possible mechanisms for this phenomenon.