Project description:The myxozoan Tetracapsuloides bryosalmonae is the causative agent of proliferative kidney disease (PKD) – a disease of salmonid fishes, notably of the commercially farmed rainbow trout Oncorhynchus mykiss. Both wild and farmed salmonids are threatened by this virulent/deadly disease, which is often expressed by swollen kidneys. In order to understand the causes and consequences of the disease, we studied the immune response towards the parasite. To profile the influence of the disease on these cells, we produced a transcriptome of teleost RBCs in health and disease. Compared to erythrocytes originating from healthy fish, PKD fundamentally altered RBCs in their metabolism, adhesion, and response to inflammation.
Project description:To date, little is known about the proteomic changes at the portals of entry in rainbow trout after infection with the myxozoans, Myxobolus cerebralis, and Tetracapsuloides bryosalmonae the causative agents of whirling disease and proliferative kidney disease, respectively. Therefore, the aim of this study was to provide the first proteomic profiles of the host in the search for evasion strategies against single and coinfection with M. cerebralis and T. bryosalmonae. One group of fish was initially infected with M. cerebralis and another group with T. bryosalmonae. After 30 days, half of the fish in each group were co-infected with the other parasite. Using a quantitative proteomic approach, we investigated proteomic changes in the caudal fins and gills of rainbow trout before and after co-infection. In the caudal fins, 16 proteins were differentially regulated post exposure to M. cerebralis, whereas 27 proteins were differentially modulated in the gills of the infected rainbow trout post exposure to T. bryosalmonae. After co-infection, 4 proteins involved in parasite recognition and the regulation of host immune responses were differentially modulated between the groups in the caudal fin. In the gills, 11 proteins involved in parasite recognition and host immunity, including 4 myxozoan proteins predicted to be virulence factors, were differentially modulated. The results of this study increase our knowledge on rainbow trout co-infections by myxozoan parasites and rainbow trout immune responses against myxozoa at the portals of entry, supporting a better understanding of these host-parasite interactions.
Project description:Hepatocytes of the mammalian liver are organized in liver lobules and operate in a spatially-dependent manner. Cells in different positions along the lobule’s porto-cenrtal axis, defined by the directionality of blood flow, express different genes and perform different liver tasks. Gradients of the transcriptome along liver lobule axis has been recently established, yet not for the hepatocyte proteome. We used two surface markers whose levels are inversely zonated – CD73 with a decreasing gradient from pericentral to periportal hepatocytes and E-cadherin with increasing gradient from portal to central hepatocytes. By staining for both surface markers, we efficiently isolated bulk populations of hepatocytes from distinct lobule layers by Fluorescence Activated Cell Sorting (FACS). Over all, we sorted 100,000 hepatocytes from each of eight spatially distinct populations, from five different mice. Cells were washed, digested by trypsin and subjected to LC-MS/MS. More cells from same populations from the same mice were also collected for mRNA sequencing and microRNA microarray profiling, to achieve a multi-omic view on spatially sorted hepatocytes, for better understanding of the transcriptomic and post-transcriptomic levels of regulation of liver zonation.
