Stimulation of the cellular immune response to lymphocytic choriomeningitis (LCM) virus infection in suckling mice.

Death occurred earlier and its rate was higher in one-week-old mice treated with phytohaemagglutinin (PHA) and subsequently inoculated intracerebrally with LCM virus than in their virus infected but untreated littermates. Thus PHA treatment contributed to the outcome of LCM virus infection in the form of lethal meningitis. The course of LCM virus infection in 1-week-old PHA treated mice was similar as in the untreated 2-week-old mice. This indicates that PHA treatment accelerated the development of cell mediated immunological capacity in suckling mice.