In another study, injectable methacrylated algihnate cryogels were created by a double‐crosslinking strategy associated with the sequential treatment of radical polymerization and Ca2+‐mediated ionic crosslinking.[319] The alginate cryogels loaded with OVA, GM‐CSF, and CpG effectively recruited and activated DCs and induced strong OVA‐specific cytotoxic T‐lymphocyte and humoral responses, leading to strong protective immunity against HER2/neu‐overexpressing breast cancer cells. The gene discussed is ERBB2; the disease is breast cancer.