藻胆蛋白色素肽与癌光啉光敏作用的比较实验

Comparison Experiment of Photosensitive Effect between Phycobiliprotein Chromophore Peptide and PhotofrinⅡ

目的:比较藻胆蛋白色素肽与癌光啉photofrinⅡ的光动力学疗法(photodynam ic therapy,PDT)效果与日光光敏作用。方法:分析藻胆蛋白酶解产物藻红蛋白R-PEβ亚基、藻蓝蛋白的CCP1、CCP3片段与photofrinⅡ的光谱特性,用MTT等方法检测其对小鼠S180细胞、小鼠移植瘤的PDT杀伤作用及对小鼠骨髓细胞、水蚤的日光光毒性。结果:photofrinⅡ在250 nm-650 nm区间有多个吸收峰,在紫外光区有很强的吸收峰,而三种蛋白酶解产物的光谱较单一,其中R-PEβ亚基、CCP1在可见光区有1~2较强的吸收峰;当光敏剂在瘤体旁注射量为50μg/个(瘤体),He-Ne激光照射剂量为120 J/cm2,瘤体大小在直径为0.5 cm^0.7 cm,phofofrinⅡ、CCP1、CCP3在照射后7天的抑瘤率分别为61%、46%及81%;用广谱性碘钨灯为光源,当光敏剂的浓度为100μg/mL,光照剂量为45 J/cm2,photofrinⅡ对小鼠S180细胞及骨髓细胞的光敏杀伤作用分别为20%及33%,而R-PEβ亚基则分别为68%及95%;如果用100μg/mL的CCP1、CCP3、photofrinⅡ及不同照射剂量的碘钨灯为激发光源处理水蚤,结果发现,光毒性对水蚤生存率长短的影响具时间积累效应,在相同光照强度条件下,photofrinⅡ的光毒性最大,CCP3次之,CCP1最弱。结论:藻胆蛋白酶解产物R-PEβ亚基、CCP1、CCP3光谱单一、PDT作用效果良好、毒副作用弱且具一定的荧光活性可作为新一代光敏剂选择的对象。

Objective： To compare the PDT and light photosensitive effect between Phycobiliprotein Chromophore peptides and Photofrin Ⅱ. Methods： Analyzed the spectroscope properties of R-phycoerythrin （R-PE） β subunit, C-phycocyanin chromophore peptides CCP1、CCP3 and photofrin Ⅱ; The PDT effect of R-PE β subunit on S180 cell, tumor bearing mice and light photosensitive effect on mouse marrow cell and daphnia were measured by MTT method. Results： There were multi-absorption peaks in photofrin Ⅱ between 250 nm-650 nm, The higher absorption peaks were located in 250 nm-450 nm; whereas, there are only one or two absorption peaks of Chromophore peptides R-PE β subunit, CCP1 and CCP3 in visible light area. In vivo test, in the condition of tumor diameter between 0.5 cm-0.7cm and the irradiation dose of 120 J/cm^2, the tumor inhibited rates of CCP1、CCP3 and photofrin Ⅱ after 7 days were 61%、46% and 81%. In vitro test, when treated with 100 μg/mL photofrin Ⅱ, irradiated with 45 J/cm^2, the survivala rate of S180 cell and mouse marrow cell were 20 % and 33 %, whereas, when treated with R-PE β subunit, the survival rate of S180 cell and mouse marrow cell were 65 % and 95 %; The phototoxicity of photofrin Ⅱ, CCP1 and CCP3 on daphnia was time and dose dependent by using iodine-tungsten lamp as light source, photofrin Ⅱ showed stronger phototoxicity than CCP1 and CCP3. Conclusion： With the advantage of good light absorbent character, weak phototoxicity, better PDT effect and special fluorescence activity, R-PE β subunit, CCPI and CCP3 are the attractive option for improving the selectivity of PDT.