Reversible Monolayer/Spheroid Cell Culture Switching by UCST-Type Thermoresponsive Ureido Polymers

Abstract

Multicellular spheroids have been studied in the fields of oncology, stem cell biology, and tissue engineering. In this study, we found a new polymer material for thermo-controlled spheroid/monolayer cell culture switching. The polymers that have pendant ureido groups (ureido polymers) exhibited upper critical solution temperature-type phase separation behavior. Cells in monolayer culture were converted to spheroids by the addition of ureido polymers below phase separation temperature (T). Time-lapse observations indicated that cells began to migrate and aggregate to form the spheroids to avoid contact with phase-separated polymer (coacervates) on the surface of the culture dish. We supposed that the coacervates seemingly suppressed interaction between cell and the dish surface or extracellular matrices. By increasing culture temperature above T, the spheroids began to collapse into a monolayer of cells due to dissolution of the coacervates. These results indicated that cell morphology could be repeatedly switched by changing the culture temperature in the presence of ureido polymers.

High-resolution imaging of a cell-attached nanointerface using a gold-nanoparticle two-dimensional sheet

“…The cell imaging was conducted in water or in ProLong antifade reagent (Thermo Fisher, USA) as a mounting medium. For live-cell imaging, the 3T3 fibroblasts with stably expressed venus-paxillin were cultured in Dulbecco’s modified Eagles medium (DMEM)-low glucose medium supplemented with 10% fetal bovine serum (FBS), 100 U/mL penicillin, 100 μg/mL streptomycin and 250 μg/mL G418 50, 51 . The AuOA sheet was rinsed twice with sterile PBS, replaced with the culture medium and pre-incubated at 37 °C for 30 min.…”

Synthetisch hergestellte, transient thermoresponsive Homopolymere mit einer oberen kritischen Lösungstemperatur für physiologisch relevante Anwendungen

“…Es konnte ferner bestätigt werden, dass in wässriger Umgebung unterhalb der UCST Poly(HPMA‐GA) auch beide Verbindungen (hydrophiles BSA und hydrophobes Nilrot) gleichzeitig einschließen kann (Abbildung S10). Sowohl in UCST‐ als auch LCST‐Polymeren treten im kollabierten Zustand hydrophobe Domänen auf, in die hydrophobe Moleküle eingelagert werden können . Doch allein für unser Poly(HPMA‐GA)‐UCST‐Polymer ist man nun auch in der Lage, hydrophile Proteine unterhalb der UCST‐Phasenübergangstemperatur einzulagern.…”

Design of a Tunable Self‐Oscillating Polymer with Ureido and Ru(bpy)3 Moieties

“…[18][19][20] Briefly,p otassium cyanate was added to PA Aa queous solution, and the solution was stirred at 60 8 8Cf or 24 h. After the reaction,t he polymer was purified by dialysis in water,a nd obtained by lyophilization. [18][19][20] Briefly,p otassium cyanate was added to PA Aa queous solution, and the solution was stirred at 60 8 8Cf or 24 h. After the reaction,t he polymer was purified by dialysis in water,a nd obtained by lyophilization.…”

“…These polymers have applications as smart materials,i ncluding soft actuators,b iosensors,d rug delivery systems,a nd cell culture materials. [19,20] In this study,anovel UCST-type self-oscillating polymer was designed by introducing the catalyst for the oscillating chemical reaction into the PAU. [8,9] We have demonstrated the utility of self-oscillating materials as autonomous biomimetic materials,such as autonomous transport tubes, [10] artificial cells and amoeba composed of block copolymers, [11,12] and autonomous functional surfaces composed of polymer brushes.…”

“…To induce UCST-type behavior in aqueous solutions, polymer-polymer interactions must be stronger than polymer-solvent interactions at lower temperatures.I np revious studies,i th as been suggested that UCST-type polymers in aqueous media could be designed by introducing electrostatic interactions or hydrogen bonding to the polymer chains. [19,20] In this study,anovel UCST-type self-oscillating polymer was designed by introducing the catalyst for the oscillating chemical reaction into the PAU. [18] Thephase transition temperatures (T p )o fP AUsc an be regulated over aw ide temperature ranges (5-65 8 8C).…”