Aza-Reversine Promotes Reprogramming of Lung (MRC-5) and Differentiation of Mesenchymal Cells into Osteoblasts

Reversine or 2-(4-morpholinoanilino)-N6-cyclohexyladenine was originally identified as a small organic molecule that induces dedifferentiation of lineage-committed mouse myoblasts, C2C12, and redirects them into lipocytes or osteoblasts under lineage-specific conditions (LISCs). Further, it was proven that this small molecule can induce cell cycle arrest and apoptosis and thus selectively lead cancer cells to cell death. Further studies demonstrated that reversine, and more specifically the C2 position of the purine ring, can tolerate a wide range of substitutions without activity loss. In this study, a piperazine analog of reversine, also known as aza-reversine, and a biotinylated derivative of aza-reversine were synthesized, and their potential medical applications were investigated by transforming the endoderm originates fetal lung cells (MRC-5) into the mesoderm originated osteoblasts and by differentiating mesenchymal cells into osteoblasts. Moreover, the reprogramming capacity of aza-reversine and biotinylated aza-reversine was investigated against MRC-5 cells and mesenchymal cells after the immobilization on PMMA/HEMA polymeric surfaces. The results showed that both aza-reversine and the biofunctionalized, biotinylated analog induced the reprogramming of MRC-5 cells to a more primitive, pluripotent state and can further transform them into osteoblasts under osteogenic culture conditions. These molecules also induced the differentiation of dental and adipose mesenchymal cells to osteoblasts. Thus, the possibility to load a small molecule with useful “information” for delivering that into specific cell targets opens new therapeutic personalized applications

Quantification of Bioorthogonal Stability in Immune Phagocytes Using Flow Cytometry Reveals Rapid Degradation of Strained Alkynes

One of the areas in which bioorthogonal chemistrychemistry performed inside a cell or organismhas become of pivotal importance is in the study of host–pathogen interactions. The incorporation of bioorthogonal groups into the cell wall or proteome of intracellular pathogens has allowed study within the endolysosomal system. However, for the approach to be successful, the incorporated bioorthogonal groups must be stable to chemical conditions found within these organelles, which are some of the harshest found in metazoans: the groups are exposed to oxidizing species, acidic conditions, and reactive thiols. Here we present an assay that allows the assessment of the stability of bioorthogonal groups within host cell phagosomes. Using a flow cytometry-based assay, we have quantified the relative label stability inside dendritic cell phagosomes of strained and unstrained alkynes. We show that groups that were shown to be stable in other systems were degraded by as much as 79% after maturation of the phagosome