Photodynamic Activity of Photogem® in Leishmania Promastigotes and Infected Macrophage

Objectives: This study aimed to evaluate the effect of photodynamic therapy (PDT) with Photogem⃝R in promastigotes of Leishmania braziliensis and Leishmania major, and in infected macrophages. Materials & methods: The following parameters were analyzed: Photogem⃝R internalization, mitochondrial activ- ity, viability, tubulin marking and morphological alterations in promastigotes and viability in infected macrophages. Results: Photogem⃝R accumulated in the cytosol and adhered to the flagellum. Changes were observed in the mitochondrial activity in groups maintained in the dark, with no viability alteration. After PDT, viability decreased up to 80%, and morphology was affected. Conclusion: The results point out that PDT with Photogem⃝R can reduce parasite and macrophage viability. Lay abstract: Cutaneous Leishmaniasis is a disease that can cause deforming lesions, the treatment of which is highly toxic. It is considered a neglected disease and little progress has been made in the treatment of this disease. Photodynamic therapy can be an alternative treatment which is less costly, and involves local treatment of the lesion, thereby reducing side effects for the patient. The present study aims to test the photodynamic therapy with Photogem, a photo sensitive drug, and to verify if the parasites can be affected by this therapy, aiming to apply this therapy in lesions in patients in the near future.