Anti-GK1 antibodies damage Taenia crassiceps cysticerci through complement activation

Taeniasis-cysticercosis, a zoonosis caused by Taenia solium, is prevalent in underdeveloped countries, where marginalization promotes its continued transmission. Pig cysticercosis, an essential stage for transmission, is preventable by vaccination. An efficient multiepitope vaccine against pig cysticercosis, S3Pvac, was developed. Previous studies showed that antibodies against one of the S3Pvac components, GK-1, are capable of damaging T. solium cysticerci, inhibiting their ability to transform into the adult stage in golden hamster gut. This study is aimed to evaluate one of the mechanisms that could mediate anti-GK-1 antibody-dependent protection. To this end, pig anti-GK-1 antibodies were produced and purified by using protein A. Proteomic analysis showed that the induced antibodies recognized the respective native cysticercal protein KE7 (Bobes et al. Infect Immun 85:e00395-17, 2017) and two additional T. solium proteins (endophilin B1 and Gp50). A new procedure to evaluate cysticercus viability, based on quantifying the cytochrome c released after parasite damage, was developed. Taenia crassiceps cysticerci were cultured in the presence of differing amounts of anti-GK-1 antibody and complement in a saturating concentration, along with the respective controls. Cysticercus viability was assessed by recording parasite motility, trypan blue exclusion, and cytochrome c levels in cysticercal soluble extract. Anti-GK-1 antibody significantly increased cysticercus damage as measured by all three methods. Parasite evaluation by electron microscopy after treatment with anti-GK-1 antibody plus complement demonstrated cysticercus damage as shorter, capsule-severed microtrichia; a decrease in glycocalyx length with respect to untreated cysts; and disaggregated desmosomes. These results demonstrate that anti-GK-1 antibodies damage cysticerci through classic complement activation.

Hydatidosis of camel (Camelus dromedarius) at Jijiga municipal abattoir, Eastern Ethiopia: prevalence, associated risk factors and financial implication

A cross-sectional study was conducted from November 2010 to May 2011 to estimate the prevalence of camel hydatidosis, associated risk factors and financial loss in Jijiga municipal abattoir, Somali Regional State, Eastern Ethiopia. Accordingly, of the total 400 inspected camel, 92 (23 %) camels and 109 organs were positive for hydatid cyst with the highest proportion recorded in lung (56 %) followed by liver (33.9 %), spleen (7.3 %) and kidneys (2.8 %). The prevalence of hydatidosis significantly varied among age categories (P < 0.05), sex (P < 0.05) and body condition score (P < 0.05) of camels. Hence, there is higher likelihood for occurrence of camel hydatidosis among the older age groups (OR 1.8, 95 % CI 1.2, 3.3), in female camels (OR 2.8, 95 % CI 1.7, 4.7) and in poor body conditioned camels (OR 4.1, 95 % CI 2.2, 7.9) than younger camels, males and camels with good body condition score, respectively. Of the total 288 examined cysts for fertility and viability, 59.7 % (172/288) were fertile while the rest 24.0 % (69/288) cysts were sterile. Of the 172 fertile cysts 69.8 % (n = 120) were viable and 30.2 % (n = 52) were non-viable. The rest 16.3 % (47/288) cysts were found dead. It was also observed that the pulmonary and hepatic cysts had fertility rate of 63.7 % (116/182) and 57.4 % (54/94), respectively. The total annual direct financial loss recorded in this study as result of organs condemnation due to hydatid cyst, was 12,147.75 Ethiopian birrs ($714.57 or $7.77/camel). If this value could be extrapolated to the infected camel population of the region, financial loss due to hydatidosis could be enormous. In conclusion, this study showed the importance of hydatidosis and the associated direct financial loss due to the condemnation of organs affected by hydatid cyst in the study area.