In addition, the team combined the application of anti-PD-L1 peptide (PPA) to alleviate the immunosuppressive microenvironment of tumors, and found that the combination could further enhance the activation of CD4+, CD8+ T cells, and NK cells by PDT and PTX-induced ICD, and promote the secretion of cytokines such as TNF-α and IL-12 to significantly inhibit tumor growth and metastasis. Here, CD4 is linked to neoplasm.