| 5%～10% of HIV infection are caused by blood transfusion or blood products. However, at current level of test techology, HIV can not be completely checked out by hematological virus screening. Thus, being in urgent need, it is investigated in hot domestically and abroad to create an effective and doable virus inactivation technique in order to prevent HIV infection via blood and blood products. In this study, the bacteriophage f2, Japanese encephalitis virus (JEV) and HIV have been used as test virus. The blood disinfection including UVC irradiation,γ-Rays irradiation,Riboflavin photochemical treatment, Hypericin photochemical treatment, MB photochemical have been compared each other. After the MB photochemical treatment has been determined as the best method of blood disinfection, the optimum inactivating condition was screened by the orthogonal assay, and the efficacy of virucide has been verificated adequately. To evaluate the acute and chronic toxic effect of MB photochemical treatment, the Kunming Mice and the Japanese Rabbit have been used respectively as test animals, on which have been examined the hepatic function and renal function by plasma automatic biochemical analysis equipment. After that, the mutation effect of Japanese Rabbit's lymphocyte was detected by micronucleus test and multinucleated cell assay, then the micronucleus rate and the Hprt locus mutation rate were used as evaluative indexes. The main results are described as follows: 1. At the designed largest dose of screen test, bacteriophage f2 in blood could reduced by 1.46 log, 1.10 log, 2.25 log, 4.27 log, 5.37 log when treated with 1500μW/cm2 UVC irradiation, 400Gyγ-Rays irradiation , 40μmol/l Riboflavin combine with irradiation of 40000Lux visible light for 40 min, 20μmol/l Hypericin combine with irradiation of 40000Lux visible light for 40 min, 10μmol/l MB combine with irradiation of 40000Lux visible light for 40 min. At the same condition, the free hemoglobin in plasma increased 279.52 mg/l, 8444.31 mg/l, 2.72 mg/l, 3.35 mg/land 3.05 mg/l respectively. According to the principle of effectively inactivating the bacteria and best keep the biologic effects of blood components, MB photochemical treatment has been chose as the optimal technique of inactivating the virus in blood. 2. The results of orthogonal assays indicated that, the inactivation efficacy for virus in blood by MB photochemical reaction was influenced by MB content, the intensity and treating time of visible light irradiation. The initial screening condition(15 μmol/LMB,density of 40000 Lux,40 min irradiation ), which could reduce phage f2 in blood more than 5 log. When certain dosages were used, the value of T/E of MB and irradiation of visible light was >1. It indicated that MB and visible light have synergetic effects. 3. According to the photochemical treatment model, the HIV-1 in blood could be reduced over 5 log by 5μmol/L MB combined with 40 000Lux of visible light irradiated for 30 min, 10μmol/L MB combined with 40 000Lux of visible light irradiated for 20 min, 15μmol/L MB combined with 40 000Lux of visible light irradiated for 10 min. The Japanese encephalitis virus(JEV) in blood could be reduced more than 7 log by 15μmol/L MB combined with 40 000Lux of visible light irradiated for 30 min. 4. The acute toxicity test of MB showed that the livability of mice is 100%, even though the concentration of MB (15mmol/l) in mice's body is 800 times than the best treated condition (15μmol/l). The significance test demonstrated that there is no significant change between the experimental group and the control group of body weight changes. Through examined by automatic biochemical analysis equipment, there was not significantly change among the plasma of disinfected blood, and its contents of proteins and most biochemical parameters all remained within the normal ranges. 5. The chronic toxicity test of MB revealed that the livability of rabbit is 100%, even the concentration of MB (604μmol/l) in rabbit's body is 80 times than the best treated condition (15μmol/l). Through examined by automatic biochemical analysis equipment, there was not significantly change among the plasma of disinfected blood, the components of proteins and most biochemical parameters all remained within the normal ranges.6. The average micronucleus rate and Hprt locus mutation rate induced by MB were neither significantly different between the experimental group and the control group (2.14±1.0‰VS 1.63±1.03‰, P>0.05; 0.980±0.033‰VS 0.983±0.001‰,P>0.05). These experimental data proved that MB did not lead to chromosome mutation.
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