PRELIMINARY EVALUATION OF CELL MEDIATED IMMUNITY IN CYNOMOLGUS AND RHESUS MONKEYS VACCINATED WITH JUNIN STRAIN XJ-44

Abstract

Vaccination of five cynomolgus and five rhesus monkeys with Junin virus_ strain XJ-44 produced mild lymphopenia relative to control groups of equal size, as expected with live attenuated viral vaccine. Transient T-cell depression was detected in both species by the formation of fewer E rosettes among peripheral blood lymphocytes the second day after infection. Over the course of 56 days of observation, no significant change in EA or EAC rosetting cells was detected. Washed peripheral blood lymphocytes from vaccinated monkeys showed no significant in vitro change in responsiveness to concanavalin A, phytohemagglutinin, pokeweed mitogen, or protein A stimulation. Specific stimulation occurred in vitro by 18 days after infection with Junin antigen in cynomolgus monkeys and was detectable at 7 weeks post infection. The response of rhesus lymphocytes to Junin antigen was minimally detectable at 28 days postinfection.