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bioRxiv · 10.1101/2022.01.12.476059

A new method for the sampling and preservation of placental specimens in low-resource settings for histology and analysis of nucleic acids

Strassmann, B. I.·Potoczak, P. S.·Rysenga, C.·Lieberman, R. W.·Vincenz, C.
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Abstract

Collection, preservation, and shipment of histological specimens in low-resource settings is challenging. We present a novel method that achieved excellent preservation of placental specimens from rural Mali by using formalin fixation, ethanol dehydration, and long-term storage in a solar-powered freezer. Sample preservation success was 92%, permitting evaluation of current and past malaria infection, anemia, placental maturity, and inflammation. Using RNAscope(R) hybridization we were able to visualize cell-specific gene expression patterns in the formalin-fixed paraffin-embedded (FFPE) specimens. Additionally, our method entailed mirrored sampling from the two cut faces of a cotyledon, one for the FFPE workflows and the other for storage in RNAlater and RNA-seq.

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Strassmann, B. I., Potoczak, P. S., Rysenga, C., Lieberman, R. W., Vincenz, C.. 2022-01-18. A new method for the sampling and preservation of placental specimens in low-resource settings for histology and analysis of nucleic acids. https://doi.org/10.1101/2022.01.12.476059

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