Background: Yellow cattle and water buffalo are two of the most important natural hosts forSchistosoma japonicumin China. Previous observation has revealed that yellow cattle are more suited to the development ofS. japonicumthan water buffalo. Understanding more about the molecular mechanisms involved in worm development, as well as the pathological and immunological differences between yellow cattle and water buffalo post infection withS japonicumwill provide useful information for the vaccine design and its delivery procedure.Results: The worm length (p< 0.01), worm recovery rate (p< 0.01) and the percentage of paired worms (p< 0.01) were significantly greater in yellow cattle than those in water buffalo. There were many white egg granulomas in the livers of yellow cattle, but fewer were observed in water buffalo at 7 weeks post infection. The livers of infected yellow cattle contained significantly increased accumulation of inflammatory cells, and the schistosome eggs were surrounded with large amounts of eosinophil infiltration. In contrast, no hepatocyte swelling or lymphocyte infiltration, and fewer white blood cells, was observed in water buffalo. The percentage of CD4⁺T cells was higher in yellow cattle, while the percentage of CD8⁺T cells was higher in water buffalo from pre-infection to 7 w post infection. The CD4/CD8 ratios were decreased in both species after challenge with schistosomes. Comparing with water buffalo, the IFN-γ level was higher and decreased significantly, while the IL-4 level was lower and increased gradually in yellow cattle from pre-infection to 7 w post infection.Conclusions: In this study, we confirmed that yellow cattle were more suited to the development ofS. japonicumthan water buffalo, and more serious pathological damage was observed in infected yellow cattle. Immunological analysis suggested that CD4⁺T cells might be an integral component of the immune response and might associate with worm development in yellow cattle. A shift from Th1 to Th2 type polarized immunity was only shown clearly in schistosome-infected yellow cattle, but no shift in water buffalo. The results provide valuable information for increased understanding of host-schistosome interactions, and for control of schistosomiasis.

Schistosomiasis japonica is prevalent in Asian countries and it remains a major public health problem in China. The major endemic foci are the marsh and lake regions of southern China, particularly the Dongting Lake region bordering Hunan and Hubei provinces, and the Poyang Lake region in Jiangxi province. Domestic ruminants, especially bovines, have long been considered to play a major role in the transmission of Schistosoma japonicum to humans. A miracidial hatching technique was used to investigate the prevalence of S. japonicum infections in domestic ruminants and field feces collected from two towns located to the south and east of Dongting Lake, Hunan province, between 2005 and 2010. The overall prevalence of infection was not significantly reduced from 4.93% in 2005 to 3.64% in 2008, after which it was maintained at this level. Bovines comprised 23.5–58.2% of the total infected ruminants, while goats comprised 41.8–76.5%. Infection rates in cattle and goats were significantly higher than those found in buffalo in most study years. The prevalence in buffalo younger than three years was significantly higher than that in those aged over three years. All the positive field samples of feces were derived from bovines in Nandashan. In Matang Town, 61.22% of the positive field feces were from bovines, while the rest were from goats. The positive rates for field feces were approximately the same in April and November/October. The present study found that bovines and goats are major sources of S. japonicum infection in the Dongting lake region and there was age-related resistance in buffalo. Both bovines and goats should be treated equally when controlling S. japonicum infections in the Dongting lake region. It is essential to conduct an additional mass treatment in late March or early April, in addition to the original treatment scheme.

Schistosomiasis remains a major public health concern in China and an epidemiological survey has revealed that schistosome-infected bovines and goats are the main transmission sources for the disease. Therefore, development of a sensitive technique for the diagnosis of schistosomiasis in domestic animals is necessary. A novel colloidal gold immunochromatography assay (GICA) strip was developed for detecting Schistosoma japonicum in domestic animals. The colloidal gold was conjugated with recombinant streptococcal protein G (rSPG). As the test and control lines, the schistosome soluble egg antigen and rSPG, respectively, were blotted on nitrocellulose membrane. The lowest detectable serum dilution was 1∶640 for schistosome-infected buffaloes. The cross-reaction rate of GICA was 14.29% with Paramphistomum sp. in buffaloes, 16.67% with Haemonchus sp. in goats, and 33.33% with Orientobilharzia sp. in goats. These results were slightly lower and similar to those obtained through ELISA. Moreover, the strips for detecting S. japonicum in mice, rabbits, buffaloes, and goats showed high sensitivity (100.00%, 100.00%, 100.00%, and 100.00%, respectively) and specificity (100.00%, 100.00%, 94.23%, and 88.64%, respectively). And the sensitivity or specificity of the GICA strips did not present any significant differences after storage for 12 months at room temperature. When compared with ELISA, the GICA strips exhibited similar sensitivity and specificity in the diagnosis of schistosomiasis in mice, rabbits, buffaloes, and goats. Besides, only 5 μl of serum are required for the test and the detection can be completed within 5 min. This study is the first to develop a GICA strip using gold–rSPG conjugate for the diagnosing of schistosomiasis in domestic animals, and preliminary results showed that the developed strip may be suitable for large-scale screening of schistosomiasis in endemic areas.

Background: More than 46 species of mammals can be naturally infected with Schistosoma japonicum in the mainland of China. Mice are permissive and may act as the definitive host of the life cycle. In contrast, rats are less susceptible to S. japonicum infection, and are considered to provide an unsuitable micro-environment for parasite growth and development. Since little is known of what effects this micro-environment has on the parasite itself, we have in the present study utilised a S. japonicum oligonucleotide microarray to compare the gene expression differences of 10-day-old schistosomula maintained in Wistar rats with those maintained in BALB/c mice. Results: In total 3,468 schistosome genes were found to be differentially expressed, of which the majority (3,335) were down-regulated (≤ 2 fold) and 133 were up-regulated (≥ 2 fold) in schistosomula from Wistar rats compared with those from BALB/c mice. Gene ontology (GO) analysis revealed that of the differentially expressed genes with already established functions or close homology to well characterized genes in another organisms, many are related to important biological functions or molecular processes. Among the genes that were down-regulated in schistosomula from Wistar rats, some were associated with metabolism, signal transduction and development. Of these genes related to metabolic processes, areas including translation, protein and amino acid phosphorylation, proteolysis, oxidoreductase activities, catalytic activities and hydrolase activities, were represented. KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis of differential expressed genes indicated that of the 328 genes that had a specific KEGG pathway annotation, 324 were down-regulated and were mainly associated with metabolism, growth, redox pathway, oxidative phosphorylation, the cell cycle, ubiquitin-mediated proteolysis, protein export and the MAPK (mitogen-activated protein kinases) signaling pathway. Conclusions: This work presents the first large scale gene expression study identifying the differences between schistosomula maintained in mice and those maintained in rats, and specifically highlights differential expression that may impact on the survival and development of the parasite within the definitive host. The research presented here provides valuable information for the better understanding of schistosome development and host-parasite interactions.

Total fertilization failure (TFF) occurs in 1–3% of total intracytoplasmic sperm injection (ICSI) cycles and can reoccur in subsequent cycles. Despite the high success rate with the application of assisted oocyte activation (AOA), there is still a small number of couples who cannot obtain fertilized eggs after conventional calcium (Ca²⁺) ionophores-based ICSI-AOA. Six couples experiencing repeated TFF or low fertilization (<10%) after ICSI and conventional ICSI-AOA were enrolled in this study. Compared with the regular ICSI group and the conventional ICSI-AOA group, the new AOA method, a combination of cycloheximide (CHX) and ionomycin, can significantly increase the fertilization rate from less than 10 up to approximately 50% in most cases. The normal distribution of sperm-related oocyte activation factor phospholipase C zeta (PLCζ1) in the sperms of the cases indicated the absence of an aberrant Ca²⁺signaling activation. The results of the whole-embryo aneuploidies analysis indicated that oocytes receiving the novel AOA treatment had the potential to develop into blastocysts with normal karyotypes. Our data demonstrated that CHX combined with ionomycin was able to effectively improve the fertilization rate in the majority of patients suffering from TFF. This novel AOA method had a potential therapeutic effect on those couples experiencing TFF, even after conventional AOA, which may surmount the severe fertilization deficiencies in patients with a repeated low fertilization or TFF.

Schistosomiasis japonica is a common zoonosis. Domestic animals are the primary source of infection and play an important role in disease transmission. The prevalence and infectivity of this disease in domestic animals in China have significantly decreased and, for this reason, diagnostics with a higher sensitivity have become increasingly necessary. It was reported that polymerase chain reaction (PCR)-based methods could be used to detect schistosome infection in humans and animals and presented a high sensitivity and specificity. The present study aimed to develop a PCR-based method for detection of Schistosoma japonicum infection in domestic animals. A specific nested-PCR assay was developed to detect S. japonicum infection in domestic animals via amplification of a 231-bp DNA fragment of retrotransposon SjR2. The developed assay was first used in sera and dry blood filter paper (DBFP) from goats and buffaloes at different time points of infection. Then, 78 DBFPs from 39 artificially-infected bovines at 14 and 28 days post-infection and 42 DBFPs from schistosome-negative bovines from the city of Huangshan in the Anhui province were used to evaluate the diagnostic validity. Furthermore, this assay was used to detect S. japonicum infection in domestic animals in Dongzhi and Wangjiang counties. The expected PCR product was detected in eggs and adult worms of S. japonicum and blood samples from S. japonicum-infected goats and water buffaloes, but not from Fasciola and Haemonchus contortus worms. The nested-PCR assay could detect the target S. japonicum DNA in DBFPs from goats and buffaloes after day 3 post-infection. The sensitivity in buffaloes at 14 and 28 days post-infection was 92.30% (36/39) and 100% (39/39), respectively. The specificity was 97.60% (41/42). The positivity rates in Dongzhi and Wangjiang counties were 6.00% and 8.00% in bovines and 22.00% and 16.67% in goats, respectively. The positivity rates in goats in both counties were higher than those in bovines with a significant difference in Dongzhi County but not in Wangjiang County (P < 0.05 and P = 0.23, respectively). Our results suggest that the developed nested-PCR assay may be used for the diagnosis of S. japonicum infection in domestic animals, and the control of S. japonicum infection in goats should be paid more attention.