Tissue Specific Profiling of Females of Schistosoma japonicum by Integrated Laser Microdissection Microscopy and Microarray Analysis

Schistosomes are parasitic worms responsible for important human diseases in tropical and developing nations. There is urgent need to develop new drugs and vaccines to augment current treatments for this disease. In recent years, concerted efforts by many laboratories have led to extensive genetic sequencing of the parasites, and the publication of genome sequence for two agents of schistosomiasis appears imminent. This genetic information has revealed many molecules expressed by the schistosome parasites for which no functional information is available. This lack of information extends to ignorance of where in the complex multicellular schistosome parasites the genes are expressed. We integrated two molecular and cellular techniques to address these knowledge gaps. We used laser microdissection microscopy to dissect small but highly important tissues involved in nutrition and reproduction from sections of female Schistosoma japonicum. From these dissected tissues we then used a broad molecular biology method to identify the multiple genes active in these tissues. Our approach has allowed us to formulate the basis of a “gene atlas” for schistosome parasites, defining the expression repertoire of specific tissues. The better understanding of the roles of tissues in parasite biology, especially in development, reproduction and interactions with its human hosts, should promote future investigations into pathogenesis and control of these significant parasites

Transcriptional Changes in Schistosoma mansoni during Early Schistosomula Development and in the Presence of Erythrocytes

Schistosome blood flukes cause more mortality and morbidity than any other human worm infection, but current control methods primarily rely on a single drug. There is a desperate need for new approaches to control this parasite, including vaccines. People become infected when the free-swimming larva, the cercaria, enters through the skin and becomes the schistosomulum. Schistosomula are susceptible to immune responses during their first few days in the host before they become adult parasites. We characterised the genes that these newly transformed parasites switch on when they enter the host to identify molecules that are critical for survival in the human host. Some of these highly up-regulated genes can be targeted for future development of new vaccines and drugs

Microarray analysis of the Schistosoma japonicum transcriptome

Schistosomiasis, a disease of humans caused by helminth parasites of the genus Schistosoma, kills 200 to 500 thousand people annually, endangering over 600 million people world-wide with 200 million people infected in 2003 [1, 2]. Three species of schistosome are primarily responsible for human infections, namely, Schistosoma haematobium, endemic to Africa, India, and the Middle East, S. mansoni, endemic to Africa / South America, and S. japonicum endemic to China and the Philippines [3]. The major pathological effects of schistosomiasis result from the deposition of parasite ova in human tissues and the subsequent intense granulomatous response induced by these eggs. There is a high priority to provide an effective sub-unit vaccine against these schistosome flukes, using proteins encoded by cDNAs expressed by the parasites at critical phases of their development. One technique that may expedite this gene identification is the use of microarrays for expression analysis. A 22,575 feature custom oligonucleotide DNA microarray designed from public domain databases of schistosome ESTs (Expressed Sequence Tags) was used to explore differential gene expression between the Philippine (SJP) and Chinese (SJC) strains of S. japonicum, and between males and females. It was found that 593, 664 and 426 probes were differentially expressed between the two geographical strains when mix sexed adults, male worms and female worms were compared respectively. Additionally, the study revealed that 1,163 male- and 1,016 female-associated probes were differentially expressed in SJP whereas 1,047 male- and 897 female-associated probes were differentially expressed in SJC [4]. Further to this, a detailed real time PCR expression study was used to explore the differential expression of eight genes of interest throughout the SJC life cycle, which showed that several of the genes were down-regulated in different life cycle stages. The study has greatly expanded previously published data of strain and gender-associated differential expression in S. japonicum. Further, the new data will provide a stepping stone for understanding the complexities of the biology, sexual differentiation, maturation, and development of human schistosomes, signaling new approaches for identifying novel intervention and diagnostic targets against schistosomiasis [4]

Microarray analysis of the Schistosoma japonicum transcriptome

Schistosomiasis, a disease of humans caused by helminth parasites of the genus Schistosoma, kills 200 to 500 thousand people annually, endangering over 600 million people world-wide with 200 million people infected in 2003 [1, 2]. Three species of schistosome are primarily responsible for human infections, namely, Schistosoma haematobium, endemic to Africa, India, and the Middle East, S. mansoni, endemic to Africa / South America, and S. japonicum endemic to China and the Philippines [3]. The major pathological effects of schistosomiasis result from the deposition of parasite ova in human tissues and the subsequent intense granulomatous response induced by these eggs. There is a high priority to provide an effective sub-unit vaccine against these schistosome flukes, using proteins encoded by cDNAs expressed by the parasites at critical phases of their development. One technique that may expedite this gene identification is the use of microarrays for expression analysis. A 22,575 feature custom oligonucleotide DNA microarray designed from public domain databases of schistosome ESTs (Expressed Sequence Tags) was used to explore differential gene expression between the Philippine (SJP) and Chinese (SJC) strains of S. japonicum, and between males and females. It was found that 593, 664 and 426 probes were differentially expressed between the two geographical strains when mix sexed adults, male worms and female worms were compared respectively. Additionally, the study revealed that 1,163 male- and 1,016 female-associated probes were differentially expressed in SJP whereas 1,047 male- and 897 female-associated probes were differentially expressed in SJC [4]. Further to this, a detailed real time PCR expression study was used to explore the differential expression of eight genes of interest throughout the SJC life cycle, which showed that several of the genes were down-regulated in different life cycle stages. The study has greatly expanded previously published data of strain and gender-associated differential expression in S. japonicum. Further, the new data will provide a stepping stone for understanding the complexities of the biology, sexual differentiation, maturation, and development of human schistosomes, signaling new approaches for identifying novel intervention and diagnostic targets against schistosomiasis [4]

Transcriptional profiles of adult male and female Schistosoma japonicum in response to insulin reveal increased expression of genes involved in growth and development

Microarray analysis was used to investigate differential gene regulation in adult male and female Schistosoma japonicum cultured in the presence or absence of insulin in vitro. A total of 1,101 genes were up- or down-regulated in response to insulin, the majority of differential expression occurring 24 h after the addition of insulin to the cultures. Genes differentially expressed in male or female worms were predominantly involved in growth and development, with significant sex-specific differences in transcriptional profiles evident. Insulin appeared to promote protein synthesis and control protein degradation more prominently in male parasites. The study also indicated that insulin plays a more pronounced role in the uptake of glucose in unpaired female parasites, as reflected in the increased stimulation of gene expression of the phosphatidylinositol 3-kinase sub-pathway of insulin signalling. Insulin may also impact on the sexual differentiation and fecundity of female schistosomes by activation of the mitogenic-activated protein kinase sub-pathway

Transcriptomics tool for the human Schistosoma blood flukes using microarray gene expression profiling

We report the design, fabrication, and validation of a microarray covering the majority of the Schistosoma japonicum and Schistosoma mansoni transcriptomes. The oligonucleotide microarray contains 12,166 S. mansoni and 7055 S. japonicum target sequences. A confidence threshold of 60.001 (P value) was used in all analyses. The cross hybridization potential of the microarray was representative of 10,362 probes detected in both channels, while 12,052 probes hybridised to S. japonicum and 11,254 probes hybridised to S. mansoni. Differential hybridisation consisted of 3422 probes to S. mansoni mRNA and 3103 probes to S. japonicum mRNA. Important biological functions, such as transport, metabolism, immune evasion and host–parasite immunological interplay, cell communication, and sexual maturation are represented on this microarray. This is the first microarray commercially manufactured for studying schistosomes, and the large size and veriWed quality of the resource demonstrate its power for characterising the schistosome transcriptome

Oligonucleotide microarray analysis of strain- and gender-associated gene expression in the human blood fluke, Schistosoma japonicum

Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes) of the genus Schistosoma. Schistosomiasis japonica, a zoonosis caused by Schistosoma japonicum, is endemic to the Philippines and China. We utilised a 22,575 feature custom oligonucleotide DNA microarray designed from public domain databases of schistosome-expressed sequence tags to explore differential gene expression between the Philippine (SJP) and Chinese (SJC) strains of S. japonicum, and between male and female S. japonicum. We found that 593, 664 and 426 probes were differentially expressed between the two geographical strains when we compared mix sexed adults, male worms and female worms. Additionally, the study revealed that 1163 male- and 1016 female-associated probes were differentially expressed in SJP whereas 1047 male- and 897 female-associated probes were differentially expressed in SJC. The study greatly expands previously published data of strain and gender-associated differential expression in S. japonicum. Further, these new data provide a stepping stone for understanding the complexities of the biology, sexual differentiation, maturation, and development of human schistosomes, signaling new approaches for identifying novel intervention and diagnostic targets against schistosomiasis

Oligonucleotide microarray analysis of strain- and gender-associated gene expression in the human blood fluke, Schistosoma japonicum

Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes) of the genus Schistosoma. Schistosomiasis japonica, a zoonosis caused by Schistosoma japonicum, is endemic to the Philippines and China. We utilised a 22,575 feature custom oligonucleotide DNA microarray designed from public domain databases of schistosome-expressed sequence tags to explore differential gene expression between the Philippine (SJP) and Chinese (SJC) strains of S. japonicum, and between male and female S. japonicum. We found that 593, 664 and 426 probes were differentially expressed between the two geographical strains when we compared mix sexed adults, male worms and female worms. Additionally, the study revealed that 1163 male- and 1016 female-associated probes were differentially expressed in SJP whereas 1047 male- and 897 female-associated probes were differentially expressed in SJC. The study greatly expands previously published data of strain and gender-associated differential expression in S. japonicum. Further, these new data provide a stepping stone for understanding the complexities of the biology, sexual differentiation, maturation, and development of human schistosomes, signaling new approaches for identifying novel intervention and diagnostic targets against schistosomiasis