Low Surface Potential with Glycoconjugates Determines Insect Cell Adhesion at Room Temperature

Abstract

Cell-coupled field-effect transistor (FET) biosensors have attracted considerable attention because of their high sensitivity to biomolecules. The use of insect cells (Sf21) as a core sensor element is advantageous due to their stable adhesion to sensors at room temperature. Although visualization of the insect cell–substrate interface leads to logical amplification of signals, the spatiotemporal processes at the interfaces have not yet been elucidated. We quantitatively monitored the adhesion dynamics of Sf21 using interference reflection microscopy (IRM). Specific adhesion signatures with ring-like patches along the cellular periphery were detected. A combination of zeta potential measurements and lectin staining identified specific glycoconjugates with low electrostatic potentials. The ring-like structures were disrupted after cholesterol depletion, suggesting a raft domain along the cell periphery. Our results indicate dynamic and asymmetric cell adhesion is due to low electrostatic repulsion with fluidic sugar rafts. We envision the logical design of cell–sensor interfaces with an electrical model that accounts for actual adhesion interfaces.

Nano-Topographically Guided, Biomineralized, 3D-Printed Polycaprolactone Scaffolds with Urine-Derived Stem Cells for Promoting Bone Regeneration

“…In addition, the water contact angle of NMS was significantly lower than that of MS, which indicated the greater existence of mineralized substances deposited onto the scaffolds. In the field of bone repair, the surface charge of biological scaffolds plays an important role in regulating various cell behaviors [ 43 , 44 ]. The Zeta potential of BS, NS, MS, and NMS was −49.44 ± 3.75 mV, 58.35 ± 4.04 mV, 43.37 ± 3.15 mV, and −18.71 ± 3.57 mV at a pH of 7.4, respectively.…”

Effective methods for immobilization of non-adherent Pv11 cells while maintaining their desiccation tolerance

“…It is possible that FBS in the medium interferes with the electrostatic interaction between cells and substrates, which would explain the weak adhesion of Pv11 cells under normal culture conditions. Sf21 cells, another type of insect cell, have been shown to have a low negative electrostatic potential of the plasma membrane, but they achieve strong focal adhesion by forming a characteristic glycoconjugate raft in the presence of FBS (Matsuzaki et al 2022). If Pv11 cells lack this specialized raftforming ability, it might further explain why they are unable to attach to surfaces when FBS is present.…”