Single-cell atlas of a non-human primate reveals new pathogenic mechanisms of COVID-19

Stopping COVID-19 is a priority worldwide. Understanding which cell types are targeted by SARS-CoV-2 virus, whether interspecies differences exist, and how variations in cell state influence viral entry is fundamental for accelerating therapeutic and preventative approaches. In this endeavor, we profiled the transcriptome of nine tissues from a Macaca fascicularis monkey at single-cell resolution. The distribution of SARS-CoV-2 facilitators, ACE2 and TMRPSS2, in different cell subtypes showed substantial heterogeneity across lung, kidney, and liver. Through co-expression analysis, we identified immunomodulatory proteins such as IDO2 and ANPEP as potential SARS-CoV-2 targets responsible for immune cell exhaustion. Furthermore, single-cell chromatin accessibility analysis of the kidney unveiled a plausible link between IL6-mediated innate immune responses aiming to protect tissue and enhanced ACE2 expression that could promote viral entry. Our work constitutes a unique resource for understanding the physiology and pathophysiology of two phylogenetically close species, which might guide in the development of therapeutic approaches in humans. Bullet pointsO_LIWe generated a single-cell transcriptome atlas of 9 monkey tissues to study COVID-19. C_LIO_LIACE2+TMPRSS2+ epithelial cells of lung, kidney and liver are targets for SARS-CoV-2. C_LIO_LIACE2 correlation analysis shows IDO2 and ANPEP as potential therapeutic opportunities. C_LIO_LIWe unveil a link between IL6, STAT transcription factors and boosted SARS-CoV-2 entry. C_LI

Generation of a Hutchinson-Gilford progeria syndrome monkey model by base editing

Many human genetic diseases, including Hutchinson-Gilford progeria syndrome (HGPS), are caused by single point mutations. HGPS is a rare disorder that causes premature aging and is usually caused by a de novo point mutation in the LMNA gene. Base editors (BEs) composed of a cytidine deaminase fused to CRISPR/Cas9 nickase are highly efficient at inducing C to T base conversions in a programmable manner and can be used to generate animal disease models with single amino-acid substitutions. Here, we generated the first HGPS monkey model by delivering a BE mRNA and guide RNA (gRNA) targeting the LMNA gene via microinjection into monkey zygotes. Five out of six newborn monkeys carried the mutation specifically at the target site. HGPS monkeys expressed the toxic form of lamin A, progerin, and recapitulated the typical HGPS phenotypes including growth retardation, bone alterations, and vascular abnormalities. Thus, this monkey model genetically and clinically mimics HGPS in humans, demonstrating that the BE system can efficiently and accurately generate patient-specific disease models in non-human primates.

Isolation, cultivation, and identification of embryonic stem cells of rhesus monkey / 第三军医大学学报

Objective To isolate and identify embryonic stem (ES) cells of rhesus monkey from mature blastocysts cultured in vitro . Methods Rhesus monkey blastocysts were obtained after in vitro maturation of oocytes, fertilization and maturation of early embryos. After the blastocysts were hatched naturally from the zone pellucida, the inner cell mass (ICM) was dislodged from blastocysts using the sealed end of a finely drawn Pasteur pipette and co cultured with the feeder cells. The ICM, resembling embryonic stem cell colony, was isolated, cultured, and identified. Results A total of 92 normal GV oocytes were obtained from 4 FSH prime rhesus monkeys. Six blastocysts with high quality were selected from 22 oocytes after culture in HECM 10 medium. One of the rhesus monkey ES cell lines, i.e. RS5 cell line, was finally isolated from 3 of the inner cell mass isolated from the 6 blastocysts. The RS5 cells presented a high nucleus/cytoplasm ratio, prominent nucleoli, and flatter colonies with individual and distinct cells. After successive passages for 5 months passage, the RS5 cells remained a normal karyotype, i.e. 42 of chromosomes and alkaline phosphatase (AP) positive, which meant the RS5 ES cell colony remained undifferentiated. After high density culture for a longer time, the ES cell could differentiate into multi types of cells. Conclusion The RS5 cell line has the ability to self renew and potential to differentiate. Thus, RS5 cell line belongs to embryonic stem cells.