Immunotherapy regimens for combination with photodynamic therapy aimed at eradication of solid cancers

摘要

Due to inflammatory/immune responses elicited by photodynamic therapy (PDT), this modality is particularly suitable in combination with various forms of immunotherapy for an improved therapeutic gain. A wide variety of approaches that may be applicable in this context include those focusing on amplifying the activity of particular immune cell types (neutrophils, macrophages, dendritic cells, natural killer cells, helper or cytotoxic T lymphocytes). Another type of approach is to focus on a specific phase of immune response development, which comprises the activation of non-specific inflammatory immune effectors, immune recognition, immune memory, immune rejection, or blocking of immune suppression. These different strategies call for a variety of immunotherapeutic protocols to be employed in combination with PDT. These include treatments such as: i) non-specific immunoactivators (e.g. bacterial vaccines), ii) specific immune agents (cytokines, or other activating factors), iii) adoptive immunotherapy treatments (transfer of dendritic cells, tumor-sensitized T lymphocytes or natural killer cells), or iv) their combinations. Techniques of gene therapy employed in some of these protocols offer novel opportunities for securing a potent and persistent immune activity. Using PDT and immunotherapy represents an attractive combination for cancer therapy that is capable of eradicating both localized and disseminated malignant lesions.