Mesenchymal stem cells (MSC) are not universal and may be subject to dynamic changes upon local milieus in vivo and after isolation and cultivation in vitro. Here, we demonstrate that MSC derived from murine pericardial adipose tissue (pMSC) constitute two cohorts of population distinguished by the level of CD73 expression (termed as CD73high and CD73low pMSC). Transplantation of two types of cells into mouse hearts after myocardial infarction (MI) revealed that the CD73high pMSC preferentially brought about structural and functional repair in comparison to the PBS control and CD73low pMSC. Furthermore, the CD73high pMSC displayed a pronounced anti-inflammatory activity by attenuating CCR2+ macrophage infiltration and upregulating several anti-inflammatory genes 5 days after in vivo transplantation and ex vivo cocultivation with peritoneal macrophages. The immunomodulatory effect was not seen in cocultivation experiments with pMSC derived from CD73 knockout mice (CD73-/-) but was partially blocked by pretreatment of the A2b receptor antagonist, PSB603. The results highlight a heterogeneity of the CD73 expression that may be related to its catalytic products on the modulation of the local immune response and thus provide a possible explanation to the inconsistency of the regenerative results when different sources of donor cells were used in stem cell-based therapy.

BackgroundInjury may induce a sequential activation of intrinsic reparative activity that supports the maintenance of tissue homeostasis.MethodIn the present experiments, we investigated whether myocardial infarction (MI) was able to reinstate the expression of Wilms’ tumor factor 1 (WT1) as a key hallmark of fetal reprograming in the pericardial adipose-derived stem cells (pADSC). We characterized the immunophenotypical markers, cardiac potential, and reparative activity of WT1-expressing pADSC (WT1pos) isolated MI Wistar rats with an intact pericardial sac in which cardiac transudate was accumulated, sampled, and analyzed.ResultsThe WT1pos cells formed colony-like aggregates in culture that subsequently generated phase-bright cells that homogenously constituted WT1 expression (> 98%). The WT1pos cells shared identical surface markers with canonical pADSC, but enhanced transcripts for cardiogenesis (isl-1, gata-4, Sox2 and Tbx18) as well as cardiac commitment (endothelial: 28%; cardiomyogenic: 12.3%) in defined conditions. Remarkably, cardiac transplantation of WT1pos cells promoted regional angiogenesis and myogenesis which led to significant functional amelioration of the infarcted hearts. Furthermore, we demonstrated that WT1pos cells uniquely secreted hepatocyte growth factor (HGF) as a key antiapoptotic factor that promotes cardiac repair.ConclusionInjury-associated fetal reprogramming in pADSC facilitates cardiac differentiation and promotes the reparative activity by enhancing HGF production. As such, injury-“conditioned” pADSC may represent a useful autologous cell donor from infarcted patients for cell-based therapy.

Diagnostics based on circulating circular RNA (circRNA) is an emerging field for noninvasive molecular diagnosis, owing to the stable circular structure of circRNA. However, the uniquely circular structure still poses a challenge for circRNA quantification in the research community. Here, we verified the discrepancy in the circRNA quantification by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and reverse transcription-droplet digital polymerase chain reaction (RT-ddPCR), which is caused by the rolling reverse transcription (RT) product originating from the circular structure. In addition, we detected the stability of cell-free circRNA in serum/ plasma and determined the pre-analysis sampling procedure that will compromise the quantification of circRNA. Our results showed that prolonged RT incubation time resulted in multiple PCR products from circular RNA, which will reduce the accuracy of circRNA quantification by RT-qPCR technology, whereas ddPCR can address this limitation and could be a good alternative to qPCR for circRNA quantification. CircRNA showed a high stability in promptly separated serum/ plasma but not in delay-separated samples.

Background Intestinal dysbiosis is believed to be one of the factors inducing neonatal necrotizing enterocolitis (NEC). Probiotics have been employed to treat NEC in a number of animal experiments and clinical trials, and some significant benefits of utilizing probiotics for the prevention or alleviation of NEC have been confirmed. However, the mechanism underlying the efficacy of probiotics in treating NEC has not been elucidated. Results Impairment of the intestinal barrier, which was characterized by the decreased expression of tight junction components, was observed in the pathogenesis of NEC. The probiotic mixture alleviated this intestinal damage by enhancing the function of the barrier. Meanwhile, the probiotics remodeled the composition of the intestinal microbiota in NEC mice. Furthermore, increased expression of the pregnane X receptor (PXR) was observed after treatment with the probiotic mixture, and PXR overexpression in Caco-2 cells protected the barrier from lipopolysaccharide (LPS) damage. Further research showed that PXR could inhibit the phosphorylation of c-Jun N-terminal kinase (JNK) and could increase the expression of tight junction components. Conclusions Our study confirmed that probiotics could ameliorate intestinal lesions by enhancing the function of the mucosal barrier. Specifically, probiotics may target PXR, which may subsequently enhance the expression of tight junction components by inhibiting the phosphorylation of JNK and enhance the function of the barrier.