Lymphocyte proliferation to HGXPRT in acute and convalescent malaria. CD4+ and CD8+ T cell division following PBMC stimulation with HGXPRT expressed as the percentage of CFSE dim cells following background subtraction. A. PBMC response in 34 acute (day 0) and 12 convalescent (day 28) subjects. The proportion with proliferation at day 28 was significantly less than at day 0 (p = 0.035). No HGXPRT proliferation was detected in 15 malaria unexposed controls. The horizontal solid line represents the group median and the dotted line the background cut-off for positive responses. B. Longitudinal HGXPRT responses in 5 subjects during acute malaria (day 0) and 7 and 28 days after drug treatment.