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Haeberlein, S.

Publications and source records attributed to Haeberlein, S..

3 recordsLinked to original sources

Single-cell transcriptomics identifies a p21-activated kinase important for survival of the zoonotic parasite Fasciola hepatica

Knowledge on the cell types and cell-specific gene expression of multicellular pathogens facilitates drug discovery and allows gaining a deeper understanding of pathogen biology. By utilizing single-cell RNA sequencing (scRNA-seq), we analyzed 19,581 cells of a globally prevalent parasitic flatworm, the liver fluke Fasciola hepatica, which causes a neglected tropical disease and zoonosis known as fascioliasis. We identified 15 distinct clusters, including cells of the reproductive tract and gastrodermis, and report the identification and transcriptional characterization of potential differentiation lineages of stem cells within this parasite. Furthermore, a previously unrecognized ELF5- and TRPMPZQ-expressing muscle cell type was discovered, characterized by high expression of protein kinases. Among these, the p21-activated kinase PAK4 was essential for parasite survival. These data provide novel insight into the cellular composition of a complex multicellular parasite and demonstrate how gene expression at single-cell resolution can serve as a resource for the identification of new drug targets.

molecular biology↗

Spatial transcriptomics of a parasitic flatworm provides a molecular map of vaccine candidates, drug targets and drug resistance genes

The spatial organization of gene expression dictates tissue functions in multicellular parasites. Here, we present the first spatial transcriptome of a parasitic flatworm, the common liver fluke Fasciola hepatica. We identified gene expression profiles and marker genes for eight distinct tissues and validated the latter by in situ hybridization. To demonstrate the power of our spatial atlas, we focused on genes with substantial medical importance, including vaccine candidates (Ly6 proteins), drug targets ({beta}-tubulins, protein kinases) and drug resistance genes (glutathione S-transferases, ABC transporters). Several of these genes exhibited unique expression patterns, indicating tissue-specific biological functions. Notably, the prioritization of tegumental protein kinases identified a PKC{beta}, for which small-molecule targeting caused parasite death. Our comprehensive gene expression map provides unprecedented molecular insights into the organ systems of this complex parasitic organism, serving as a valuable tool for both basic and applied research.

molecular biology↗

Target-based discovery of a broad spectrum flukicide

Diseases caused by parasitic flatworms impart a considerable healthcare burden worldwide. Many of these diseases - for example, the parasitic blood fluke infection, schistosomiasis - are treated with the drug praziquantel (PZQ). However, PZQ is ineffective against disease caused by liver flukes from the genus Fasciola. This is due to a single amino acid change within the target of PZQ, a transient receptor potential ion channel (TRPMPZQ), in Fasciola species. Here we identify benzamidoquinazolinone analogs that are active against Fasciola TRPMPZQ. Structure-activity studies define an optimized ligand (BZQ) that caused protracted paralysis and damage to the protective tegument of these liver flukes. BZQ also retained activity against Schistosoma mansoni comparable to PZQ and was active against TRPMPZQ orthologs in all profiled species of parasitic fluke. This broad spectrum activity was manifest as BZQ adopts a pose within the binding pocket of TRPMPZQ dependent on a ubiquitously conserved residue. BZQ therefore acts as a universal activator of trematode TRPMPZQ and a first-in-class, broad spectrum flukicide.

microbiology↗