Biology subjects

Henthorn, C. R.

Publications and source records attributed to Henthorn, C. R..

5 recordsLinked to original sources

bioRxiv2026

CELeidoscope: quad-fluorescent Caenorhabditis elegans strain for tissue-specific spectral single-cell analyses

Cell and tissue-specific transcriptomic profiling of Caenorhabditis elegans is commonly achieved by fluorescence tagging or staining of targeted cell populations, often followed by fluorescence-activated cell sorting (FACS) and RNA sequencing. However, these approaches typically require separate strains for each labeled population, increasing labor and experimental variability while limiting direct comparison of multiple tissues within the same genetic background. To address this limitation and establish proof of concept, we engineered CELeidoscope, a multicolored C. elegans strain that enables spectral sorting of multiple major cell types within a single strain population. Strain construction was carried out using a high-throughput screening method that reduces the labor and plastic costs associated with transgene integration and outcrossing. Four primary tissues (body muscle, neurons, intestinal, and pharyngeal muscle cells) were tagged with spectrally distinct fluorescent proteins, allowing compatibility with viability and nucleic acid dyes. Using spectral flow cytometry, dissociated CELeidoscope cell suspensions could be sorted based on their spectral profiles, with cell recovery rates approximating the expected cell counts in whole organisms. Transcriptomic analysis of the sorted cell populations further validated the identity of the sorted populations, with recovered cells exhibiting gene expression signatures consistent with their intended cell and tissue identities. Together, these results establish CELeidoscope as a versatile tool for multiplexed cell-type isolation in C. elegans, providing a framework for tissue-specific analyses from a common strain background.

microbiology↗

bioRxiv2026

Deep phenotypic profiling uncovers cryptic effects of antifilarial drugs

The anthelmintics ivermectin, albendazole, and diethylcarbamazine are the backbone of mass drug administration (MDA) campaigns targeting human filariasis, yet their direct effects on parasites are still not fully defined or understood. The clinical effects of these drugs are stage dependent, resulting in effective clearance of circulating microfilariae but only limited activity against adult worms, a pattern that complicates disease surveillance and elimination efforts. Although molecular targets have been identified or proposed for some antifilarial drugs, their precise modes of action remain opaque, and conventional in vitro assays of motility or viability have generally failed to reflect pharmacologically relevant effects. There is growing evidence that cryptic phenotypes involving altered host-parasite interactions, including changes in parasite secretions, may help reconcile these discrepancies. Focusing on the causative species of lymphatic filariasis, we used high content imaging and quantitative mass spectrometry to enable deeper phenotypic profiling of drug responses in microfilariae and adult worms exposed to antifilarial compounds. In microfilariae, altered environmental conditions (temperature and salinity) lead to modest ivermectin effects on motility at therapeutic concentrations. In adult parasites, we show that drug responses vary with worm age and that different anthelmintics induce distinct changes in the secretory proteome. This improved phenotypic resolution advances our understanding of drug action in intra-host stages and highlights how antifilarial drugs can alter secretory cargo relevant to the detection of adult parasites that persist after drug treatment.

microbiology↗

bioRxiv2024

Transcriptional phenotype of the anti-parasitic benzodiazepine meclonazepam on the blood fluke Schistosoma mansoni

There are limited control measures for the disease schistosomiasis, despite the fact that infection with parasitic blood flukes affects hundreds of millions of people worldwide. The current treatment, praziquantel, has been in use since the 1980s and there is a concern that drug resistance may emerge with continued monotherapy. Given the need for additional antischistosomal drugs, we have re-visited an old lead, meclonazepam. In comparison to praziquantel, there has been relatively little work on its antiparasitic mechanism. Recent findings indicate that praziquantel and meclonazepam act through distinct receptors, making benzodiazepines a promising chemical series for further exploration. Previous work has profiled the transcriptional changes evoked by praziquantel treatment. Here, we examine in detail schistosome phenotypes evoked by in vitro and in vivo meclonazepam treatment. These data confirm that meclonazepam causes extensive tegument damage and directly kills parasites, as measured by pro-apoptotic caspase activation. In vivo meclonazepam exposure results in differential expression of many genes that are divergent in parasitic flatworms, as well as several gene products implicated in blood feeding and regulation of hemostasis in other parasites. Many of these transcripts are also differentially expressed with praziquantel exposure, which may reflect a common schistosome response to the two drugs. However, despite these similarities in drug response, praziquantel-resistant parasites retain susceptibility to meclonazepams schistocidal effects. These data provide new insight into the mechanism of antischistosomal benzodiazepines, resolving similarities and differences with the current frontline therapy, praziquantel.

pharmacology and toxicology↗

bioRxiv2022

Resolving the origins of secretory products and anthelmintic responses in a human parasitic nematode at single-cell resolution.

Nematode excretory-secretory (ES) products are essential for the establishment and maintenance of infections in mammals and are valued as therapeutic and diagnostic targets. While parasite effector proteins contribute to host immune evasion and anthelmintics have been shown to modulate secretory behaviors, little is known about the cellular origins of ES products or the tissue distributions of drug targets. We leveraged single-cell approaches in the human parasite Brugia malayi to generate an annotated cell expression atlas of microfilariae. We show that prominent antigens are transcriptionally derived from both secretory and non-secretory cell and tissue types, and anthelmintic targets display distinct expression patterns across neuronal, muscular, and other cell types. While the major classes of anthelmintics do not affect the viability of isolated cells at pharmacological concentrations, we observe cell-specific transcriptional shifts in response to ivermectin. Finally, we introduce a microfilariae cell culture model to enable future functional studies of parasitic nematode cells. We expect these methods to be readily adaptable to other parasitic nematode species and stages.

microbiology↗

bioRxiv2022

Multivariate chemogenomic screening prioritizes new macrofilaricidal leads

Development of direct acting macrofilaricides for the treatment of human filariases is hampered by limitations in screening throughput imposed by the parasite life cycle. Efforts to circumvent arduous screening of adult filariae include drug repurposing and high-throughput screens that target commensal bacteria. In vitro adult screens typically assess single phenotypes without prior enrichment for chemicals with antifilarial potential. We developed a multivariate screen that identified dozens of compounds with submicromolar macrofilaricidal activity, achieving a hit rate of >50% by leveraging abundantly accessible microfilariae. Adult assays were multiplexed to thoroughly characterize compound activity across relevant parasite fitness traits, including neuromuscular control, fecundity, metabolism, and viability. 17 compounds from a diverse chemogenomic library elicited strong effects on at least one adult trait, with differential potency against microfilariae and adults. Stage-specific drug effects may be crucial to limiting adverse events in endemic regions, and our screen identified five compounds with high potency against adults but low potency or slow-acting microfilaricidal effects, at least one of which acts through a novel mechanism. We show that the use of microfilariae in a primary screen outperforms model nematode developmental assays and virtual screening of protein structures inferred with deep-learning. These data provide new leads for drug development, and the high-content and multiplex assays set a new foundation for antifilarial discovery.

microbiology↗