Robles, C. R. | Search bioRxiv

bioRxiv2026

Interferon lambda signaling to maternal dendritic cells protects against congenital Zika virus infection

Interferon lambda (IFN-{lambda}, type III IFN) mediates antiviral immunity at anatomic barriers, including the maternal-fetal interface. To investigate the effects of IFN-{lambda} during congenital Zika virus (ZIKV) infection, we infected mice lacking the IFN-{beta} receptor (Ifnar1-/-) or both the IFN-{beta} and IFN-{lambda} receptors (Ifnar1-/-Ifnlr1-/-) at E9 and found that loss of maternal IFN-{lambda} signaling resulted in greater transplacental transmission. We used HiPlex RNAscope on entire gravid uteruses and found that IFN-{lambda} was expressed more proximal to the site of ZIKV infection in Ifnar1-/- dams compared to Ifnar1-/-Ifnlr1-/- dams. We performed immunophenotyping of the placenta and uterus by flow cytometry and found a decrease in dendritic cells and NK cells in the uterus of Ifnar1-/-Ifnlr1-/- dams compared to Ifnar1-/- dams, but NK cell depletion did not impact fetal infection. Using conditional knockout mice, we identified maternal dendritic cells as the key IFN-{lambda} responsive cell type mediating protection against ZIKV congenital infection.

immunology↗

bioRxiv2017

A comprehensive map of genetic variation in the world’s largest ethnic group - Han Chinese

As are most non-European populations around the globe, the Han Chinese are relatively understudied in population and medical genetics studies. From low-coverage whole-genome sequencing of 11,670 Han Chinese women we present a catalog of 25,057,223 variants, including 548,401 novel variants that are seen at least 10 times in our dataset. Individuals from our study come from 19 out of 22 provinces across China, allowing us to study population structure, genetic ancestry, and local adaptation in Han Chinese. We identify previously unrecognized population structure along the East-West axis of China and report unique signals of admixture across geographical space, such as European influences among the Northwestern provinces of China. Finally, we identified a number of highly differentiated loci, indicative of local adaptation in the Han Chinese. In particular, we detected extreme differentiation among the Han Chinese at MTHFR, ADH7, and FADS loci, suggesting that these loci may not be specifically selected in Tibetan and Inuit populations as previously suggested. On the other hand, we find that Neandertal ancestry does not vary significantly across the provinces, consistent with admixture prior to the dispersal of modern Han Chinese. Furthermore, contrary to a previous report, Neandertal ancestry does not explain a significant amount of heritability in depression. Our findings provide the largest genetic data set so far made available for Han Chinese and provide insights into the history and population structure of the worlds largest ethnic group.

genetics↗