CD4 and neoplasm: The slightly acidic tumor microenvironment allowed sustained release of PTX, membrane disintegration, and constant release of IL‐2 for the stimulation of DCs, cytotoxic T‐lymphocytes, and NK cells for superior antitumor efficacy.[354] Koppolu and Zaharoff prepared antigen‐encapsulated chitosan particles using OVA as a model protein antigen and showed that chitosan particles induced maturation and cytokine production of BMDCs and macrophages to stimulate activation and proliferation of antigen‐specific CD4+ and CD8+ T cells.[355] Rebbouh et al.