TABLE 1.

Implantable and injectable biomaterial scaffolds for cancer immunotherapy.

	Material type	Payload	Results	References
Implantable scaffolds	Alginate scaffold	CAR-T cells	Proliferate T cells and reduce the unresectable or incompletely resected tumors.	Stephan et al., 2015
	Alginate scaffold	CAR-T cells, STING agonists	Stimulate systemic immune response to eliminate solid tumors.	Smith et al., 2017
	Hyaluronic acid scaffold	CAR-NK cells	Enhance the expansion, persistency and antitumor efficiency of NK cells.	Ahn et al., 2020
	Collagen and HA cross-linking scaffold	GEM, poly(I:C)	Reduce the tumor-infiltrating MDSCs and increase the number of CD8+ T cells.	Phuengkham et al., 2018
	PLG scaffold	GM-CSF, CpG-ODNs	Recruit, activate and home to lymph nodes of DCs.	Ali et al., 2009
Injectable scaffolds	Alginate hydrogel	GM-CSF	Recruit CD11b+ CD11c+ DCs into the hydrogels.	Verbeke and Mooney, 2015
	Alginate hydrogel	Microparticles, peptide antigens	Recruit and activate immune cells	Verbeke et al., 2017
	Alginate hydrogel	Celecoxib, PD-1 antibody	Regulate the immunosuppressive tumor microenvironment and improve antitumor activities.	Li Y. et al., 2016
	PEGylated poly(L-valine) hydrogel	TCL, poly(I:C)	Enhance the percentage of migratory DCs in tumor-draining lymph nodes and induce cytotoxic T-lymphocyte immune response.	Song et al., 2018
	RADA16 peptide hydrogel	PD-1 antibodies, DCs, TCL	Increase the percentage of CD8+ IFN-γ+ T cells.	Yang et al., 2018
	ROS-degradable hydrogel	GEM, PD-L1 antibody	Achieve obvious tumor suppression effects and induce a T cell immune response.	Wang C. et al., 2018
	D-tetra-peptide hydrogel	OVA, X-ray irradiated E.G7 tumor cells	Induce powerful CD8+ IFN-γ+ T cell immune response.	Luo et al., 2017
	Phospholipid hydrogel	OVA, CpG-ODN	Recruit and activate DCs, induce memory T cells response.	Han et al., 2016
	HA-Tyr hydrogel	IFN-α, sorafenib	Induce apoptosis of tumor cells and the suppress the angiogenesis.	Ueda et al., 2016
	Peptide hydrogel	CDN	Achieve powerful immune memory effect to resist a secondary injection of tumor cells.	Leach et al., 2018
	MSR	OVA, GM-CSF, CpG-ODN	Recruit DCs, increase the systemic TH1 and TH2 serum antibody and cytotoxic T cells.	Kim et al., 2015
	PEI with MSR	E7 peptide	Recruit and activate DCs and the immune response of T cells.	Li A.W. et al., 2018
	PEG, RGD, or RDG modified MSR	None	Increase BMDC activation marker expression and the innate immune cells infiltration.	Li W.A. et al., 2016