Interaction between 6/94 virus, a parainfluenza type 1 strain, and unstimulated mouse lymphocytes.

6/94 virus was found to grow in unstimulated splenic mouse lymphocytes depleted of monocyte macrophages. Both egg-grown virus and virus produced in mouse macrophage cultures induced the development of hemadsorption and the appearance of new infectious virus in the lymphocyte cultures. An antigenic relative. Sendai virus, on the contrary, was quickly inactivated in these lymphocyte cultures, in agreement with previous reports in the literature. The T lymphocyte population seemed to be the fraction principally involved in the replication of 6/94 virus. The immunization of mice with 6/94 virus and the appearance of high levels of humoral neutralizing antibodies did not inhibit completely the susceptibility of their lymphocytes to the infectious agent.