Characterization of RNA isolated from eighteen different human tissues: results from a rapid human autopsy program

Abstract

Many factors affect the integrity of messenger RNA from human autopsy tissues including postmortem interval (PMI) between death and tissue preservation and the pre-mortem agonal and disease states. In this communication, we describe RNA isolation and characterization of 389 samples from 18 different tissues from elderly donors who were participants in a rapid whole-body autopsy program located in Sun City, Arizona (www.brainandbodydonationprogram.org). Most tissues were collected within a PMI of 2–6 h (median 3.15 h; N = 455), but for this study, tissue from cases with longer PMIs (1.25–29.25 h) were included. RNA quality was assessed by RNA integrity number (RIN) and total yield (ng RNA/mg tissue). RIN correlated with PMI for heart (r = −0.531, p = 0.009) and liver (r = −558, p = 0.0017), while RNA yield correlated with PMI for colon (r = −485, p = 0.016) and skin (r = −0.460, p = 0.031). RNAs with the lowest integrity were from skin and cervix where 22.7 and 31.4 % of samples respectively failed to produce intact RNA; by contrast all samples from esophagus, lymph node, jejunum, lung, stomach, submandibular gland and kidney produced RNA with measurable RINs. Expression levels in heart RNA of 4 common housekeeping normalization genes showed significant correlations of Ct values with RIN, but only one gene, glyceraldehyde-3 phosphate dehydrogenase, showed a correlation of Ct with PMI. There were no correlations between RIN values obtained for liver, adrenal, cervix, esophagus and lymph node and those obtained from corresponding brain samples. We show that high quality RNA can be produced from most human autopsy tissues, though with significant differences between tissues and donors. The RNA stability and yield did not depend solely on PMI; other undetermined factors are involved, but these do not include the age of the donor.

Impact of different stabilization methods on RT-qPCR results using human lung tissue samples

“…Although no statistically significant differences have been observed between frozen stabilization methods, a slight better RNA stability and integrity were observed in RNL samples. Despite sample size limitations, our study provides plausible evidences for considering Bioanalyzer 2100 and RT-qPCR results as comparable methods for assessing RNA quality, in accordance with Walker et al 33 . Furthermore, it is important to note the value of selecting reference genes to conduct the experiments, i.e.…”

Can research at the end of life be a useful tool to advance HIV cure?

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Identification of cadaveric liver tissues using thanatotranscriptome biomarkers

“…Emerging research to clarify the postmortem fingerprint of mRNA transcript expression patterns of the 25,000 human genes 1,2 have been studied to clarify the secrets of how human beings die. Integrated approaches to investigate temporal variations and the eventual cessation of postmortem transcription expression patterns have influenced an upsurge in studies of the functional complexities of the thanatotranscriptome [3][4][5][6][7][8] . The thanatotranscriptome is derived from the Greek word for death (thanatos-), and it encompasses all RNA transcripts expressed from the part of genome that is still functional or that becomes awakened in internal organs of a dead body 3 .…”

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