An automatic multi-tissue human fetal brain segmentation benchmark using the Fetal Tissue Annotation Dataset

It is critical to quantitatively analyse the developing human fetal brain in order to fully understand neurodevelopment in both normal fetuses and those with congenital disorders. To facilitate this analysis, automatic multi-tissue fetal brain segmentation algorithms are needed, which in turn requires open datasets of segmented fetal brains. Here we introduce a publicly available dataset of 50 manually segmented pathological and non-pathological fetal magnetic resonance brain volume reconstructions across a range of gestational ages (20 to 33 weeks) into 7 different tissue categories (external cerebrospinal fluid, grey matter, white matter, ventricles, cerebellum, deep grey matter, brainstem/spinal cord). In addition, we quantitatively evaluate the accuracy of several automatic multi-tissue segmentation algorithms of the developing human fetal brain. Four research groups participated, submitting a total of 10 algorithms, demonstrating the benefits the dataset for the development of automatic algorithms.

Nodosome inhibition as a novel broad-spectrum antiviral strategy against arboviruses, enteroviruses and SARS-CoV-2

In the present report, we describe two small molecules with broad-spectrum antiviral activity. These drugs block formation of the nodosome. The studies were prompted by the observation that infection of human fetal brain cells with Zika virus (ZIKV) induces expression of nucleotide-binding oligomerization domain-containing protein 2 (NOD2), a host factor that was found to promote ZIKV replication and spread. A drug that targets NOD2 was shown to have potent broad-spectrum antiviral activity against other flaviviruses, alphaviruses, enteroviruses, and SARS-CoV-2, the causative agent of COVID-19. Another drug that inhibits the receptor-interacting serine/threonine-protein kinase 2 (RIPK2) which functions downstream of NOD2, also decreased replication of these pathogenic RNA viruses. The antiviral effect of this drug was particularly potent against enteroviruses. The broad-spectrum action of nodosome targeting drugs is mediated in part by enhancement of the interferon response. Together, these results suggest that further preclinical investigation of nodosome inhibitors as potential broad-spectrum antivirals is warranted.

Tyramide Signal Amplification coupled with multiple immunolabeling and RNAscope in situ hybridization in formaldehyde-fixed paraffin-embedded human fetal brain.

Several strategies have been recently introduced to improve the practicality of multiple immunolabelling and RNA in situ hybridization methods. We present a modified hybrid protocol of recently described complex detection strategies: (1) elution of antibodies prior to second round of staining (2) use of integrated polymers of HRP with secondary antibodies, and (3) tyramide signal amplification of multiple immunofluorescence labelling, to achieve a high sensitivity sequential multiple labeling using antibodies from the same species. A modified protocol of the novel RNAscope in situ hybridization method, including coupling with immunofluorescence on sections of early human fetal brain, has also been developed. These two techniques, when properly optimized, were highly compatible with routine formaldehyde-fixed paraffin-embedded tissue that preserves the best morphological characteristics of delicate fetal brain samples, allowing high power signal amplification for detection of protein and mRNA of genes that are sparsely expressed in the human fetal telencephalon.