Carbohydrate polymer-based biomaterials for light-triggered Photo-Immunotherapy: Design strategies, immune mechanisms, and translational outlook.

Recent advances in biomaterials have highlighted the immense potential of carbohydrate polymers (CHPs) as biocompatible, multifunctional platforms for cancer therapy. Indeed, the structural diversity, tunable chemistry, and inherent biological affinity of these polymers enable the precise design of systems for immune modulation. Moreover, light- and laser-driven strategies have emerged as powerful tools for achieving spatiotemporal control over therapeutic activation. Therefore, integrating CHPs with photothermal or photodynamic nanocomponents enables these hybrid systems to induce localized tumor ablation, trigger immunogenic cell death, and remodel the tumor immune microenvironment. These synergistic phototherapy-immunotherapy platforms eradicate primary tumors while promoting systemic antitumor immunity and immune memory formation. Therefore, this review aims to summarize recent advances in CHP-based biomaterials for light-mediated immune activation, focusing on mechanisms, design strategies, and therapeutic outcomes. Furthermore, challenges in tumor-specific targeting, deep-tissue light penetration, and clinical translation are critically discussed. Finally, future perspectives are proposed for the development of next-generation, smart, light-responsive carbohydrate nanomedicines to enable precision cancer immunotherapy.