Proliferative responses of infected dogs with different clinical outcomes. Shown are the proliferative responses at 10 month post-infection of PBMCs from polysymptomatic (6; ■, □), oligosymptomatic (8; ▲, △) and asymptomatic (3; ●, ○) infected dogs and control (7; ◆, ◇) dogs at 10 months post-infection to either soluble leishmanial antigens (SLA) or the P-8 proteoglycolipid complex. The responses observed at 10 months post-infection were similar to those observed for these animals at both 6 and 8 months post-infection.