*2.5. CMCh2*/*HAox4-HA0.4 Based Bioprinting*

### 2.5.1. Cell Culture

L929 Fibroblasts (ATCC, Manassas, VA, USA) were cultured in RPMI 1640 phenol red free medium (Gibco, 61870-010) supplemented with 20% fetal bovine serum (FBS, Gibco, 10270), 200 mM L-glutamine, and 1% penicillin/streptomycin (Invitrogen, Thermo Fisher). Incubation was carried out at 37 ◦C, 95% humidity, and 5% CO2. Cell culture media was changed every two days.
