Macrophage activation measured by changes in 5'-nucleotidase and alkaline phosphodiesterase I activities after infection of newborn and juvenile guinea pigs with mycobacterium microti.

Activation of alveolar, peritoneal, liver, and spleen macrophages was measured by decreased 5'-nucleotidase and elevated alkaline phosphodiesterase I activities in newborn and juvenile guinea pigs for up to 48 days after intracardiac or intranasal infection with Mycobacterium microti. Increased AP and reduced 5'-nucleotidase activity in cell lysates of macrophages appeared to be related to the carrier state during infection. Intranasal infection of 8-week-old guinea pigs with M. microti produced decreases of 5'-nucleotidase activity in alveolar macrophages during 1-8 weeks post infection and in macrophages from all four sources from 4-8 weeks.