Photodynamic Effects with 5-Aminolevulinic Acid on Cytokines and Exosomes in Human Peripheral Blood Mononuclear Cells from Patients with Crohn’s Disease

Abstract

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) which is the precursor of the photosensitizer protoporphyrin IX (PpIX) is an available treatment for several diseases. ALA-PDT induces the apoptosis and necrosis of target lesions. We have recently reported the effects of ALA-PDT on cytokines and exosomes of human healthy peripheral blood mononuclear cells (PBMCs). This study has investigated the ALA-PDT-mediated effects on PBMC subsets from patients with active Crohn’s disease (CD). No effects on lymphocyte survival after ALA-PDT were observed, although the survival of CD3−/CD19+ B-cells seemed slightly reduced in some samples. Interestingly, ALA-PDT clearly killed monocytes. The subcellular levels of cytokines and exosomes associated with inflammation were widely downregulated, which is consistent with our previous findings in PBMCs from healthy human subjects. These results suggest that ALA-PDT may be a potential treatment candidate for CD and other immune-mediated diseases.

Photodynamic Therapy for Inflammatory and Cancerous Diseases of the Intestines: Molecular Mechanisms and Prospects for Application

“…Numerous studies have showcased the considerable advantages of PDT in treating inflammatory diseases, including IBD 4 , 36 , 37 . PDT can modify cell signal transduction, regulate cytokine generation, and modulate cell surface receptor expression, thereby preserving cell vitality and exerting anti-inflammatory properties 7 , 17 , 38 . The combination of biologic therapy and immunomodulators represents an essential and indispensable approach for managing IBD, particularly in patients with more severe disease manifestations.…”

“…Given the potential accumulation of the PS in the adjacent healthy tissues, HDPDT may inadvertently cause harm to normal cells in the intestine while targeting tumor cells 2 , 14 , 15 . LDPDT shows notable efficacy in preventing mucosal damage 16 , and demonstrates excellent immunomodulatory effects 17 . Moreover, it regulates various intestinal bacterial strains and promotes neovascular closure.…”

“…The successful application of LDPDT in treating inflammatory diseases highlights its favorable safety profile for therapeutic use. [7,[17][18][19] .…”