The Effects Of Different Parameters Of PDT On The Killing Effect And Immune Effect Of Skin Squamous Cell Carcinoma A431 Cells

Background:Skin squamous cell carcinoma is a malignant disease caused by malignant changes of cuticle or accessory horny cells.It is often found in the elderly with an average age of 60 years old.Skin squamous cell carcinoma is often found in the sun exposed parts,and the patients’lesions are mostly distributed in the facial,back and other parts.The clinical treatment is usually mainly surgical treatment,and the conventional treatment methods include laser therapy,drug therapy,radiotherapy and chemotherapy.In recent years,photodynamic therapy has become an effective treatment technology for skin squamous cell carcinoma,but there is no uniform standard of treatment scheme and parameters.The results of the study on the efficacy of PDT show that the irradiation energy of laser,the concentration of photosensitizer and the incubation time of the corresponding drugs have certain influence on the efficacy of PDT,and the appropriate parameters of PDT treatment have killing effect on squamous cell.Objective:To investigate the effect of PDT on the killing effect and immune effect of skin squamous cell carcinoma A431 cells.Methods:the experimental object was human skin squamous cell line（A431）,and PDT was used to deal with photodynamic treatment of the cells.The activity of cells in each group was detected by CCK-8 method,ROS expression was detected by enzyme standard instrument,cell morphology was observed under microscope,and pictures were collected.Flow cytometry was used to detect apoptosis of cells and after co culture with A431 cells,dendritic cells were detected the expression of CD80,CD86 and MHC-II on the surface of DC.Results:（1）the inhibition effect of PDT on A431 cells was influenced by the concentration of photosensitizer and the density of light energy.In a certain range,PDT has an increasing inhibition effect on cells with the increase of photosensitizer concentration and light dose,but the inhibition effect of photodynamic therapy on cells does not increase with the increase of dose.（2）The cells without PDT treatment grew in a single piece,and the arrangement was orderly and closely,and the morphology was uniform.When the energy density was 3J/cm^2,the cell arrangement was disordered,the gap widened and the proportion of the cells collapsed and broken gradually increased with the increase of the concentration of photosensitizer.（3）With the increase of photosensitizer concentration,ROS content increased with the energy density of 3J/cm²,and the apoptosis rate of A431 cells increased.（4）The expression of CD80,CD86 and MHC-II on DC cells was not dose-dependent with the concentration of photosensitizer.When the concentration of photosensitizer is 0-31.25μg/ml,the ability of PDT treated A431 cells to induce DC maturation increases with the increase of photosensitizer concentration;when the concentration of photosensitizer exceeds 31.25μg/ml,the ability of PDT treated A431 cells to induce DC maturation decreases with the increase of photosensitizer concentration.Conclusion:（1）the photodynamic treatment with appropriate parameters has the killing effect on A431 cells.When the concentration of photosensitizer is 62.5μg/ml and the energy density is 9J/cm²,the inhibition effect of ALA PDT on A431 cells is the best.The inhibition effect of PDT on A431 cells cannot be improved by increasing the concentration of photosensitizer or the density of light energy.（2）When the energy density is 3J/cm²,the immune and killer effects of PDT treatment of A431cells are different.The immune effect and the concentration of photosensitizer are not dose-dependent,and the sensitivity concentration is 31.25μg/ml to induce DC to mature.