RNA-based logic for selective protein expression in senescent cells.

Cellular senescence is a cellular state characterized by irreversible growth arrest, resistance to apoptosis and secretion of inflammatory molecules, which is causally linked to the pathogenesis of many age-related diseases. Besides, there is accumulating evidence that selective removal of senescent cells can benefit therapies for cancer and fibrosis by modulating the inflammatory microenvironment. While the field of so-called senolytics has spawned promising small molecules and peptides for the selective removal of senescent cells, there is still no effective means to detect senescent cells in vivo, a prerequisite for understanding the role of senescence in pathophysiology and to assess the effectiveness of treatments aimed at removing senescent cells.

Selective Targeting of Tumor Cells in a Microfluidic Tumor Model with Multiple Cell Types.

Organ-on-a-chip technology allows researchers to precisely monitor drug efficacy in 3D tissue culture systems that are physiologically more relevant to humans compared to 2D cultures and that allow better control over experimental conditions as compared to animal models. Specifically, the high control over microenvironmental conditions combined with the broad range of direct measurements that can be performed in these systems makes organ-on-a-chip devices a versatile tool to investigate tumor targeting and drug delivery. Here, we describe a detailed protocol for studying the cell-selective targeting of protein drugs to tumor cells on an organ-on-a-chip system using a co-culture consisting of BT-474 cancer cells and C5120 human fibroblasts as an example.

Potent and selective eradication of tumor cells by an EpCAM-targeted Ras-degrading enzyme.

Despite decades of efforts, an urgent need remains to develop tumor cell-selective rat sarcoma (Ras)-targeting therapies that can treat patients with Ras-driven tumors. Here we report modular engineered proteins that degrade Ras selectively in tumor cells that overexpress the tumor cell marker epithelial cell adhesion molecule (EpCAM) by fusing the Ras degrader Ras-Rap1-specific endopeptidase with the translocation domain of the exotoxin A (ETA) or diphtheria toxin (DT). Redirection to EpCAM is achieved by a designed ankyrin repeat protein.

Co-Culture of Glomerular Endothelial Cells and Podocytes in a Custom-Designed Glomerulus-on-a-Chip Model Improves the Filtration Barrier Integrity and Affects the Glomerular Cell Phenotype.

Crosstalk between glomerular endothelial cells and glomerular epithelial cells (podocytes) is increasingly becoming apparent as a crucial mechanism to maintain the integrity of the glomerular filtration barrier. However, studies directly investigating the effect of this crosstalk on the glomerular filtration barrier are scarce because of the lack of suitable experimental models. Therefore, we developed a custom-made glomerulus-on-a-chip model recapitulating the glomerular filtration barrier, in which we investigated the effects of co-culture of glomerular endothelial cells and podocytes on filtration barrier function and the phenotype of these respective cell types.

Assessing the use of tumor-specific DARPin-toxin fusion proteins for ex vivo purging of cancer metastases from human ovarian cortex before autotransplantation.

Objective: To assess the use of tumor-specific designed ankyrin repeat proteins (DARPins) fused to a domain of Pseudomonas aeruginosa exotoxin A for purging of cancer metastases from the ovarian cortex.

Design: Experimental study.

Setting: University medical center.