Background: As a drug target and an antigenic agent, HIV-1 protease (HIV-1 PR) is at the center of attention for designing anti-AIDS inhibitors and diagnostic tests. In previous studies, the production of the recombinant protease has been faced with several difficulties; therefore, the aims of this study were the easy production, purification of the soluble form of protease in E. coli and investigation of its immunoreactivity.Methods: Protease coding region was isolated from the serum of an infected individual, amplified by RT-PCR and cloned into PTZ57R using TA-cloning. Protease coding frame was isolated by PCR and cloned in pET102/D. TOPO expression vector and cloned protease was expressed in Escherichia coli (E. coli) BL21. Produced recombinant protein was purified by affinity Ni-NTA column and protein concentration was checked by BCA protein assay kit. Subsequently, immunoreactivity of recombinant protease (rPR) was assayed by Western blotting and ELISA.Results: Cloning of the HIV protease by TOPO cloning system in pET102/D.TOPO was confirmed with PCR and sequencing. The concentration range of purified recombinant protein was 85 to 100mg/ml. Immunogenicity of rPR was confirmed by Western blotting and ELISA.Conclusion: Soluble production of recombinant HIV-1 protease (HIV-1 rPR) was performed successfully. This recombinant protein disclosed 86% specificity and 90% sensitivity in immunoassay tests.

Using ex vivo models of equine respiratory tract tissue has shown that SLS contributes to the ability of the equine streptococci to colonies and damage equine respiratory tract tissue. This suggests that if it were possible to elicit neutralizing anti-SLS antibodies in horses, these could contribute to protection against the equine streptococcal diseases. For this purpose recombinant GST-sagA encoded plasmid have been constructed by fusion of 166 nucleotide of sagA gene (which obtained by PCR) from streptococcus equi to pGEX-3X plasmid.Recombinant plasmid was transformed to three different competent Ecoli B121, Co+ and Plyses cells.Recombinant GST-SagA was induced by IPTG (1 mM -1M) for 4hr and purified by FFI column. It was shown that BL21 produced more recombinant protein and highly purified recombinant GST - SagA protein were obtained by FFI column. This soluble peptide was desalted and concentrated with viva science filter tube and 100 ml of 10 mg\ml of this peptide was obtained from 2000ml cell culture.

Background: We aimed to investigate the relationship between serum soluble Klotho protein (sKlotho) level and coronary artery calcification (CAC) as well as prognosis in patients with maintenance hemodialysis (MHD). Methods: Overall, 128 adult patients with end-stage renal failure treated with MHD were collected in the Sec-ond Affiliated Hospital & Yuying Children’ s Hospital of Wenzhou Medical University, Zhejiang Province, China in 2013. Serum sKlotho was detected by ELISA and coronary artery calcification was measured by mul-ti-slice spiral computed tomography (MSCT). With 36 months' follow-up, death notes such as cause of death and death time were recorded. Results: Patients were divided into low sKlotho group and high sKlotho group. Age, blood phosphorus level, hypertension incidence and incidence of diabetes mellitus of the patients in low sKlotho group was significant-ly higher than that of high sKlotho group (P<0. 05). The coronary artery calcification score (CACs) of patients in high sKlotho group was significantly lower than that of low sKlotho group (P<0. 001). Logistic regression showed that the decrease of sKlotho level (P<0. 001) was an independent risk factor for CAC progression. The mortality of the patients in low sKlotho group was higher than that of high sKlotho group. Kaplan-Meier sur-vival curve had shown that survival time of the patients in low sKlotho group was significantly lower than that of high sKlotho group (P<0. 05). Conclusion: SKlotho can increase the degree of CAC. Although MHD patients with low sKlotho level had shorter survival time, sKlotho is not an independent risk factor in prediction of prognosis of MHD patients.