| Herpes-simplex-virus- (herpes-simplex-virus, HSV) is-herpe- sviridae-α-virus-subfamily, -spherical, -the–membrane -of- the–double -stranded DNA. Herpes simplex virus keratitis (HSK) is a corneal epithelial cells infected by herpes simplex virus type I (HSV-I) directly from the point,dendritic keratitis in the corneal stroma, and the immune response caused discoid, matrix necrosis keratitis. As latenting in the trigeminal ganglion,when a combination of factors led to immunity suppressed, latent HSV-I can be re-activated, the recurrence of HSK caused repeated attacks and can cause serious damage, even vision blind. HSK has no effects against the current therapy, and because the unreasonable use of antibiotics and hormones, drug-resistant strains of the virus emerging, and so far there is no satisfactory method of treatment, many scholars at home and abroad against HSV-I think that automatically specificity immune maybe the most effective ways to control the infection. Therefore, the development of the vaccine will become the focus of HSK.DNA vaccine is consisted of the protective antigen gene and vector form. The full immunity and humoral immune response produce protective immunity and has broad application prospects. HSV-I glycoprotein B is the primary target antigen in host cells and humoral immunity. HSV-1 is specific cytotoxic T lymphocytes (CTL) main target antigen. pcDNA3-gB DNA vaccine was shown to induce the production of antibodies and cells and the immune response of mice with immune protection. However, the safety of pcDNA3-gB DNA vaccine has not yet been confirmed. Each of the vaccine in the application, the risks must be carefully carried out the assessment before its benefits. Security is a complex issue, for example, would not affect the blood physiology and blood chemistry changes, the availability of organizations to change, or even life-threatening. The result of experimental mice immunized with the general state (diet, the will, weight, general activities and mental state), the physiological index of blood, blood chemistry index, an important organ pathology and gene chip integration, preliminary confirmed pcDNA3-gB were safe in mice.First, in the different dose immunized groups and control group, they all had the good diet, weight increased, the general activities and state of mind active also well, no deaths occurred.Second, the selection of important index of blood physiology including red blood cell (RBC) and hemoglobin (HB), hematocrit (HCT), mean cell volume (MCV), RBC average hemoglobin (MCH) and the average red blood cell hemoglobin concentration (MCHC), white blood cells (WBC), platelet (PLT), RDW (RDW), the overall results of these physiological indicators reflect mice respiratory system, immune system, circulatory system and the function of blood coagulation mechanisms were good. Blood chemistry index including alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (T-BIL), blood urea nitrogen (BUN) and creatinine (Cr), serum total protein (TP), globulin (ALB ), glucose (GLU) reflected these mice heart, liver, kidney, pancreas function are normal. The experimental results can be seen from three different dose pcDNA3-gB immunized mice, the mice's blood important physical, chemical indicators of Health did not have a significant different, that's means the organ and system function of immunized mice with pcDNA3-gB were unaffected, so preliminary to confirm that pcDNA3-gB on mice system is safe.Again, selectimportant organs, heart, liver, spleen, kidney, brain, cornea, retina and the trigeminal ganglion of formalin fixed, paraffin embedded, HE staining made of pathological biopsy, which can be observed that different doses of immune pcDNA3-gB of the experimental group compared with the control group, there was no significant difference. Its general organizational structure, morphology were normal, no signs of infection by the virus. pcDNA3-gB DNA vaccine without the characteristics of virus pathogenic, the host tissues and cell structure without adverse effects. So we could say on the cell level of mice tissues and cell structure, pcDNA3-gB DNA vaccine is safe.Finally, preliminary safety study on the gene level of pcDNA3-gB vaccine. First, the results of the DNA agarose gel electrophoresis of control group and the experimental groups'eight organizations extract showed that all groups Lane can only see the two bands of the size about 100bp and more than 15, 000bp, but in about 8000bp (size of pcDNA3-gB about 8100bp) did not see purpose bands. In strict accordance with the guidelines of Molecular cloning experiment during the experiment, and repeated two times, both had the same result, so pcDNA3-gB does not exist in eight organs of the experimental groups and the control group. Second the organizations extract DNA of the experimental groups and control group for PCR amplification and agarose gel electrophoresis, results were only the pcDNA3-gB gene vaccine group had 2700bp and 5400bp bands, other groups did not appear. Further to say there were not the pcDNA3-gB gene vaccine,gB or pcDNA3 gene fragment existed in experimental and control groups. Some scholars believed that while HSV genome structure does not had the integration of genes, so the probability of DNA vaccine integrated with the host of occurrence is extremely small. Therefore, we can initially confirm on the gene level, pcDNA3-gB gene vaccine was not integrated in the host genome, it was safe.To sum up, the results of a preliminary study from the-whole-body, the-system, the-organs, the-molecular -and-the -gene- level showed that the construction of our own pcDNA3-gB DNA vaccine is safe in mice.Although the initial experiments confirmed pcDNA3-gB gene vaccine was safe in mice, but since this was the first time about safety research of pcDNA3-gB gene vaccine, the content of the study was not comprehensive, and observation time was short, the technical methods were not perfect, so it will need another long-term, comprehensive and systematic research and feasibility studies. But with the results of a series of studies of pcDNA3-gB gene vaccine, we are confident that pcDNA3-gB gene vaccine will be benefit to mankind.
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