Exogenous Cell Surface Modification with Cell Penetrating Peptide-Conjugated Lipids Causes Spontaneous Cell Adhesion

Abstract

The technique of cell patterning on a substrate is of great importance for platforms in cell-based assays. Chemical treatment of the substrate is commonly performed for cell patterning using cationic polymers, extracellular matrices, and antibodies. However, cell patterning could be easier if there is an approach to immobilize cells without treating the substrate surface. We previously reported that cell adhesion could be induced by the modification of the cellular surface with a cellpenetrating peptide (CPP)-conjugated poly(ethylene glycol)-phospholipid (CPP-PEG-lipid). This approach does not require chemical modification of the substrate surface, such as polystyrene or glass, and can be used for the cell patterning of floating cells. Here, we aimed to study the mechanism of induced cell adhesion using a representative CPP, Tat peptide (Tat-PEG-lipid). We found that cell adhesion was induced via electrostatic interactions between the Tat peptide and the substrate surface, which could be induced more efficiently by increasing the molecular weight of PEG together with CPPs but not with cationic peptides. The excluded volume effect between neighboring PEG chains could stretch the cell shape better than PEG with lower molecular weight, allowing the cell to spread firmly. In addition, Tat-PEG-lipid did not activate actin filament formation and did not influence the expression of focal adhesion kinase. Thus, the induced cell adhesion by CPP-PEG-lipid did not affect internal cell signaling.

Surface modulation of extracellular vesicles with cell-penetrating peptide-conjugated lipids for improvement of intracellular delivery to endothelial cells

“…However, the surface charge was still negative even though it shifted from the original value to a more positive value. Similar results were observed for modified cells after treatment with Tat-PEG-lipid [ 24 ]. Cationic Tat peptides are surrounded by sialic acid and membrane proteins, resulting in a slight positive shift in the zeta potential of the total charge.…”

Ferried Albumin‐Inspired Bioadhesive With Dynamic Interfacial Bonds for Emergency Rescue

“…[ 38 ] 2) TP can coagulate bacterial proteins and interfere with their metabolism. [ 39 ] It is worth mentioning that the outer layer of mammalian cell membranes contains a large number of neutral sterols and phospholipids with less negative charge (compared to bacterial cell membranes); [ 40 ] so, SPI exhibits a superior affinity for bacteria through electrostatic interaction and minimal toxicity to mammalian cells. [ 41 ]…”

Cell membrane fusion induced by surface modification with cell-penetrating peptide–lipid conjugates that facilitates close contact between distinct membranes

“…The cell surface can be modified with Tat-PEGlipids, where the Tat peptide can be displayed on the cell surface. 18,23,24 Because the Tat peptide is membranepermeable, Tat-PEG-lipids inserted into a cellular membrane can anchor to the neighboring cellular membrane through the interaction between the Tat peptide and another cellular membrane. We assumed that the cell-cell attachment by this Tat-PEG-lipid could induce spontaneous cell fusion because it is a single polymer and can achieve closer contact between two cells compared to ligand-PEG-lipids, where the two polymers interact with each other from both cellular membranes.…”