[Cellular immune response following neonatal mice immunization with vesicular stomatitis virus]

Infectious microorganisms are major sources of illness and death worldwide, and the leading cause of death in neonates. Effective vaccination of this age group is of particular importance. The lack of a response and greater susceptibility to tolerance are two major features that limit the effectiveness of vaccines in neonates. In this study we compare the cellular immune response generated following antigen injections at different times of life in newborn mice to that of adult mice. Adult and different age neonate mice were vaccinated with vesicular stomatitis virus [VSV]. One week after the last injection, cellular immunity was assayed on spleen cells that targeted EL4 infected cells using lactate dehydrogenase cytotoxicity assay. Antigen injection induced a decreased immune response in newborn mice compared with mice that had been immunized with subsequent injections. In the adult group, due to the evolution of the immune system, we observed a stronger immune response. Immunization of newborn mice may induce a reduced response when compared to adult vaccinations. However this can be corrected by the administration of additional booster doses

Optimizing primary recovery and refolding of human interferon-beta from escherichia coli inclusion bodies

The refolding of proteins from inclusion bodies is affected by several factors, including solubilization of inclusion bodies by denaturants, removal of the denaturant, and assistance of refolding by small molecule additives. The purpose of this study was optimization of recombinant human interferon-beta purification in order to achieve higher efficiency, yield, and a product with a better and more suitable biological activity. Triton X-100 and sodium deoxycholate were used to wash the recombinant human interferon-beta inclusion bodies prior to solubilization. The inclusion bodies solubilization process was performed by denaturants and reducing agents; guanidine-hydrochloride, urea, beta-mercaptoethanol and dithiothritol. The best recovery was obtained in the presence of 0.5% TritonX-100 [v/v]. Low concentrations of urea only gave a marginal improvement on the refolding of recombinant human interferon- beta. Successful refolding was achieved by gradient elution [decreasing the guanidine-hydrochloride concentration] in the presence of L-arginine. Partial purification was also achieved continuously, and recombinant human interferon-p was recovered with 93.5% purity. The interferon prepared in this project was biologically active and inhibited the replication of vesicular stomatitis virus in Hela cells, when compared to the standard interferon. In this research, the best recovery of inclusion bodies was found at a concentration 0.5 M of Triton X-100, the maximum efficiency of solubility was found in pH 10.5 and the maximum efficiency of refolding was achieved by final buffer containing 2M urea and 0.6 M L-Arg