Decoupled Surface Engineering Enables Cell-Interactive Edible Microcarriers across Food-Grade Polysaccharides

Abstract

Edible microcarriers for cultivated meat must support cell expansion while also contributing appropriately to the properties of the final food product. Food-grade polysaccharides exemplify this design challenge: despite their desirable food-related functions, they generally provide limited support for cell adhesion. This limitation calls for a strategy that introduces cell-interactive functionality without constraining bulk material selection. Here, we developed a decoupled surface-engineering strategy in which a poly-L-lysine/tannic acid (PLL/TA) interface is constructed on preformed polysaccharide microcarriers to enable cell-supportive functionality to emerge through interactions with the culture environment. On alginate microcarriers, PLL/TA modification markedly enhanced initial cell attachment, with 83% of modified microcarriers supporting attached cells compared with no detectable attachment on bare alginate. Cell-covered area subsequently reached 63.74% by Day 6, compared with 9.64% on PLL-coated microcarriers and negligible coverage on bare alginate. The PLL/TA interface promoted the recruitment of culture-medium proteins, including fibronectin, supporting an adaptive mechanism in which a cell-supportive interface develops through protein recruitment rather than predefined protein presentation. Importantly, the same surface modification enhanced early cell attachment when extended to pectin and carrageenan microcarriers and to Hanwoo bovine and Handon porcine muscle cells. On carrageenan microcarriers, the proportion of cell-bearing microcarriers increased from 30% to 100% for Hanwoo bovine cells and from 10% to 100% for Handon porcine cells following PLL/TA modification. These findings establish an adaptive and transferable surface-engineering strategy that enables cell-interactive functionality to be engineered separately from bulk material selection, expanding the design space for edible microcarriers in cultivated meat production.