CD8A and neoplasm: The study demonstrates that chitosan-coated hollow copper sulfide nanoparticles combined with CpG and near-infrared laser irradiation elicit up to a 41-fold increase in immune activation, a 19-fold enhancement in systemic CD8+ T-cell response, complete suppression of distant tumor growth for 10 days, and over 47% nanoparticle clearance within 14 days, confirming potent, systemic, and biodegradable photothermal immunotherapy efficacy [68].