Isolation in Tissue Culture of an Interfering Agent from Patients with Rubella.

The technic first described by Buescher and Parkman for isolation of an agent from patients with rubella was used in a study of 7 university students affected with this disease. 1. Agents which interfered with ECHO 11 in primary or continuous grivet monkey kidney cells or in a continuous rhesus monkey kidney cell line (LLC-MK2) were recovered from all patients. 2. The agent was recovered from upper respiratory secretions of all cases and from blood drawn during the acute phase in 4 of 7 patients. 3. Rise in the neutralizing properties of the sera obtained in the convalescent period as compared with the acute sera was a constant feature in all samples tested. 4. The usefulness of the LLC-MK2 cell line for primary isolation of this agent(s) was proven during this study.