Effect of probiotic (Saccharomyces cerevisiae) supplementation on immune response in Trypanosoma brucei brucei infected rats.

The immunomodulatory effect of the probiotic (Saccharomyces cerevisiae) on Trypanosoma brucei brucei infected rats was studied. Thirty (30) rats divided into five groups (A-E) of 6 rats each were used for the study. Groups A, B and C rats received feed supplemented with S. cerevisiae (at 0.08, 0.12 and 0.16/kg of feed, respectively) for the duration of the study. Groups D and E diets were not supplemented. All the rats in the 5 groups were immunized with 0.3 ml of 10% sheep red blood cells (SRBC) at day 7 pre-supplementation, and booster doses given every 14 days thereafter. On day 28 post supplementation (PS), rats of groups A-D were infected with 1 × 10(6) of T. brucei brucei intraperitoneally. Supplementation resulted in increases in antibody titres to SRBC which later declined following T. brucei brucei infection, but remained higher than the pre supplementation titres. At termination of the study (i.e. day 49 PS) supplemented groups had significantly (p<0.05) higher antibody titres than either the infected or the non infected controls. The total and differential leucocyte counts followed a similar pattern with initial increases in counts following supplementation followed by reductions after T. brucei brucei infection. Supplementation also resulted in decline in parasitaemia with significant difference between the supplemented groups and the un-supplemented controls on day 42 post infection. The results are indication that probiotics can be used to ameliorate the immunosuppressive effect of T. brucei brucei infections.