# Biocompatibility of Hydrogels for Glomerular 3D Co‐Culture: A Comparative Analysis

## TL;DR

This paper compares different hydrogels for growing kidney glomerulus cells in 3D, finding that GelAGE and spider silk-based hydrogels perform best.

## Contribution

The study introduces a systematic comparison of five hydrogels for 3D glomerular co-culture and identifies GelAGE and eADF4(C16)-RGD as optimal materials.

## Key findings

- GelAGE and eADF4(C16)-RGD hydrogels showed superior biocompatibility and structural support for glomerular cells.
- GelAGE was found to have favorable viscoelastic properties and ease of handling.
- These hydrogels are promising for engineering physiologically relevant 3D kidney models.

## Abstract

Conventional 2D mono‐cultures fall short in replicating the complex microenvironment of glomerular tissue, where cell–cell and cell–matrix interactions are critical. To better mimic in vivo conditions, the development of robust 3D co‐culture systems is essential. Here, we systematically evaluate five hydrogel matrices—Matrigel, alginate dialdehyde‐gelatin (ADA‐GEL), fibrin, recombinantly produced spider silk protein eADF4(C16)‐RGD, and allyl‐modified gelatin (GelAGE)—for their suitability in supporting glomerular 3D co‐culture. The hydrogels are assessed for handling properties, cell viability, and the support of physiological cell behavior using bright‐field microscopy, live/dead assays, immunofluorescence, and multiphoton imaging. Among the tested hydrogels, GelAGE and eADF4(C16)‐RGD demonstrate superior biocompatibility and structural support. Due to its ease of use and comparable biological performance, GelAGE and spider silk protein eADF(C16)‐RGD are selected for further mechanical characterization, revealing favorable viscoelastic properties. These findings position both hydrogels as a promising candidate for engineering physiologically relevant 3D glomerular models and advancing kidney tissue research.

GelAGE and recombinant spider silk hydrogels are evaluated for glomerular 3D co‐culture. GelAGE combines ease of handling with excellent biocompatibility and viscoelasticity, making it a promising scaffold for kidney tissue modeling and advanced in vitro studies.