Only 14 pages are availabe for public view
Toxoplasmosis is an infectious disease caused by an obligate intracellular parasitic protozoan, Toxoplasma gondii (T. gondii). Bone marrow-derived mesenchymal stem cells (BM-MSCs) are self-renewing, clonal precursors of non-haematopoietic tissues, with anti-inflammatory and anti-apoptotic effect. They can repair and restore several tissues, including the CNS.
This study aimed to evaluate the therapeutic effect of BM-MSCs on murine chronic toxoplasmosis experimental model. BM-MSCs were obtained from tibiae and femurs of 7-wk-old Albino donor rats. Nucleated cells were cultured and incubated till become confluent. Cells were harvested, counted and adjusted to 106 cell/ml. Female Swiss albino mice (n=100) were divided into five groups (20 mice each). Mice (n=80) were infected orally, using nasogastric feeding tube, by brain homogenate of the Me49 strain of T. gondii. group I (infected mice injected with BM-MSCs); group II (infected mice treated with combination of BM-MSCs and Spiramycin-Metronidazole); group III (infected mice treated with Spiramycin-Metronidazole); group IV (infection control) and group V (non-infected mice injected with BM-MSCs).
Mice (n=5) from each group were euthanized, at the 7th and 14th days after starting treatment administration. Deaths of mice (10 mice in each group) were recorded daily for 7 months, 2 months post infection. Parasitological examination of brain cyst count, histopathological examination of brain tissue and survival rate were assessed in each group. As regards the mean Toxoplasma brain cyst count, after 7 and 14 days, group I was significantly lower than group II, significantly higher than group III and non-statistically different from group IV. group II was significantly higher than group III and group IV. group III showed significant decrease in brain cyst count versus group IV. As regards histopathological examination of brain sections, after 7 and 14 days, group I showed the least histopathological inflammatory changes which was significantly lower than that of group IV. group II revealed the most profound histopathological inflammatory changes which was significantly higher than that of group IV. group III showed mild to moderate inflammatory changes with non-statistically significant difference from group IV. As regards survival rate, group I showed the highest mean survival time which was statistically significant versus group IV. group II showed the lowest mean survival time, which was statistically significant versus group IV. Mean survival time in group III showed non-significant difference versus group IV. 100% of mice in group V survived during the whole experimental period.
So, we concluded that, MSCs have anti-inflammatory effect and prolong the survival of T. gondii infected mice, however they have non-significant effect on brain cyst count.