Study On The Protective Effection Of The Eukaryotic Expressed Murin Ptx3Protein In The Mice Infected By SS2

Streptococcus suis(SS) is an important zoonotic pathogens, which is not only can cause sepsis, but also attack the central nervous system and other organizations, triggering meningitis, pneumonia, endocarditis, arthritis and et al. For the past10years, there were237people infected SS and resulting in the death of53people at least, hence, SS is a serious threat to the public health. SS often treated with antibiotics, which will not only enhance the resistance of SS, and also can cause a series of problems of drug residues, food safety and ect. So, a new, safe and effective treatment is needed urgently for SS.Among the first functions reported for Ptx3was its ability to bind certain pathogens, which plays an important role in the process against certain pathogens. With the application of the transgenic mice and transgenic cells, modulating the immune response and phagocytosis of Ptx3have been discovered. By the studying the interaction between the outer membrane protein A of K.pneumoniae (KpOmpA) and Ptx3, Ptx3was found regulate the inflammatory response induced by microbial constituents.The murine Ptx3protein expressed by prokaryotic and the rabbit Anti-the prokaryotic murine Ptx3protein were obtained at first. Recombinant eukaryotic expression vector pIRES-egfp-Ptx3was constructed successfully following. pIRES-egfp-Ptx3was transfected into chinese hamster ovary cells(CHO), and then the cells was cultured in the nutrient solution containing G418(700ng/mL), to screen the positive cells. The steady and expressed largely positive monoclonal cell lines was obtained by the selection of the flow cytometry, which were subcultured in serum-free medium(CD-CHO) to get cell culture supernatant. The high purity and stable eukaryotic murine Ptx3protein was purified by the glucan gel chromatography system from the supernatant. All such could lay a basis for the study of the function of the murine Ptx3protein.By studying the change of phagocytosis of Ana-1to HA9801under the effect of the Ptx3protein, the phagocytic rate (PA) and phagocytic index (PI) was improved significantly, which indicated that Ptx3protein can enhanced phagocytosis of Ana-1.To research on the regulation effect of Ptx3protein to the inflammation induced by HA9801, the air bag mice model was built. In the air bag, the number of inflammatory cells and the concentration of inflammatory factors (IL-6) induce by both HA9801and Ptx3was much more than induced by HA9801only, which confirmed that Ptx3protein could enhance the inflammatory response induced by HA9801in mice. In addition, in addition, under the role of the Ptx3protein the infected concentration of HA9801was reduced significantly in mice, so Prx3protein have a anti-inflammation effect for the mice from the infection of HA9801.