Phylogeny, envenomation syndrome, and membrane permeabilising venom produced by Australia's electric caterpillar Comana monomorpha.

Zygaenoidea is a superfamily of lepidopterans containing many venomous species, including the Limacodidae (nettle caterpillars) and Megalopygidae (asp caterpillars). Venom proteomes have been recently documented for several species from each of these families, but further data are required to understand the evolution of venom in Zygaenoidea. In this study, we examined the 'electric' caterpillar from North-Eastern Australia, a limacodid caterpillar densely covered in venomous spines. We used DNA barcoding to identify this caterpillar as the larva of the moth Comana monomorpha (Turner, 1904). We report the clinical symptoms of C. monomorpha envenomation, which include acute pain, and erythema and oedema lasting for more than a week. Combining transcriptomics of venom spines with proteomics of venom harvested from the spine tips revealed a venom markedly different in composition from previously examined limacodid venoms that are rich in peptides. In contrast, the venom of C. monomorpha is rich in aerolysin-like proteins similar to those found in venoms of asp caterpillars (Megalopygidae). Consistent with this composition, the venom potently permeabilises sensory neurons and human neuroblastoma cells. This study highlights the diversity of venom composition in Limacodidae.

Venom composition and bioactive RF-amide peptide toxins of the saddleback caterpillar, Acharia stimulea (Lepidoptera: Limacodidae).

Limacodidae is a family of lepidopteran insects comprising >1500 species. More than half of these species produce pain-inducing defensive venoms in the larval stage, but little is known about their venom toxins. Recently, we characterised proteinaceous toxins from the Australian limacodid caterpillar Doratifera vulnerans, but it is unknown if the venom of this species is typical of other Limacodidae. Here, we use single animal transcriptomics and venom proteomics to investigate the venom of an iconic limacodid, the North American saddleback caterpillar Acharia stimulea. We identified 65 venom polypeptides, grouped into 31 different families. Neurohormones, knottins, and homologues of the immune signaller Diedel make up the majority of A.stimulea venom, indicating strong similarities to D. vulnerans venom, despite the large geographic separation of these caterpillars. One notable difference is the presence of RF-amide peptide toxins in A. stimulea venom. Synthetic versions of one of these RF-amide toxins potently activated the human neuropeptide FF1 receptor, displayed insecticidal activity when injected into Drosophila melanogaster, and moderately inhibited larval development of the parasitic nematode Haemonchus contortus. This study provides insights into the evolution and activity of venom toxins in Limacodidae, and provides a platform for future structure-function characterisation of A.stimulea peptide toxins.

Disease modifying therapies for relapsing-remitting multiple sclerosis: Use and costs in Australia (1996-2019).

BACKGROUND: New disease modifying therapies (DMT) to control relapsing-remitting multiple sclerosis (RRMS) have been introduced to the market in the past few years and are now widely used in Australia. OBJECTIVE: To analyse the dispensed use of government subsidised RRMS DMTs in Australia from 1996 to 2019. METHODS: We obtained data of dispensed use of DMTs from the Australian Government's Pharmaceutical Benefits Scheme (PBS) administered by Medicare Australia. We measured use as defined daily dose (DDD) per 100,000 population per day. We obtained jurisdictional population data from the Australian Bureau of Statistics. RESULTS: Total DMT use increased by an average of 18% annually, from 2.4 (in 1996) to 69.9 DDD/100,000/day in 2019. Interferon ß1B was the most commonly used medicine between 1996 and 2000, Interferon ß1A between 2001 and 2014, and fingolimod subsequently. Among Australian states, Tasmania (the southernmost state) had the highest dispensed DMT use of 94.6 DDD/100,000/day in 2019. Concession beneficiaries under the Government's PBS had both lower use and cost per patient than general beneficiaries did. Fingolimod and ocrelizumab accounted for 55% of total expenditure on MS drug therapy in 2019. CONCLUSION: The use of oral DMTs might increasingly replace parenteral treatments in the near future. Given the current substantial government expenditure on oral DMTs, it will be imperative to examine the real world effectiveness of DMTs.