Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model

Figure 4

Differences in log-transformed stimulation indices for incubation with PMA/I between S. neurona experimentally infected and control horses. Control horses had a significantly higher stimulation index for PMA/I responses on Day 35, with a pattern demonstrating higher indices in the control group towards the end of the experiment. Lymphocyte proliferation assays using the (³H)-thymidine assay were performed with a variety of mitogens, including the pan-leukocyte stimulant, PMA/I. Stimulation indices were calculated by dividing the average counts per minute for cells stimulated with each mitogen, by the counts per minute for spontaneously proliferating cells. Average stimulation index was log-transformed and plotted against time for control (blue) and infected (white) horses. The error bars represent standard deviation about the mean. The blue star indicates a significant difference (). Day 0 = first day of experiment (Day 1 of infection).