Cryptosporidium is one of the commonest opportunistic parasites. But, its chemotherapeutic
options are limited, with controversy about the role of apoptosis in cryptosporidiosis. Caspases
are key molecules of apoptosis. The study assessed the role of apoptosis in cryptosporidiosis
by studying the relationship between the effects of phenyl vinyl sulfone (PVS), nitazoxanide
(NTZ) and combined therapy on Cryptosporidium parvum infection and caspase 3
immunostaining. Ninety female laboratory bred Swiss Albino mice were divided into two
major groups; immunocompetent and immunosuppressed. Both groups were divided into the
following subgroups, for each one respectively: negative control (1 & 6), infected control (2
& 7), infected treated with PVS (3 & 8), infected treated with NTZ (4 & 9) and infected treated
combined (5 & 10). Sacrification were done on 18th day post infection.
Histopathological study of ileum was done and endogenous developmental stages were
counted. Also, caspase 3 immunohistochemical staining was carried out on ileal sections.
Combined therapy in groups 5 &10 showed the highest reduction in mean number of endogenous
developmental stages as in G10 (P <0.05). Caspase expression in PVS treated groups (3
& 8) showed significant decrease when compared to their control groups (P < 0.05). While
there were significant increase in caspase expression in groups treated with NTZ (4 & 9)
when compared to their contorls (P < 0.05). Caspase 3 epithelial overexpression was evident
in infected immunocompetent G2 than immunosuppressed G7 (P<0.05).