Evaluation of Trilysine-Cross-Linked Gellan Gum for Intratumoral Delivery of Anti-PD-1 in a Colorectal Cancer Mouse Tumor Model

/s) for Atto 488-IgG (2.63 ± 0.32), 60-76 kDa FITC-Dextran (2.65 ± 0.31), and 150 kDa FITC-Dextran (2.80 ± 0.83), with a 70-90% recovery postbleaching. Additionally, intratumoral delivery of aPD-1 was evaluated in a CRC mouse (C57BL/6) tumor model inoculated with MC38 cells. Quantification of aPD-1 in the plasma and tumor showed an increase in concentration by 1.5- and 3-fold, respectively, when delivered using the intratumoral hydrogel route in comparison with either intraperitoneal (i.p.) or drug-free intratumoral administration. Overall, this noncytotoxic hydrogel provided an alternative delivery route for aPD-1, maximizing its presence both in circulating blood and in the treatment site, serving as a simple localized delivery system in CRC.