Análise comparativa da produção do Vaccinia virus Ankara modificado (MVA) em dois sistemas: cultivo primário de fibroblastos de embrião de galinha versus membrana corioalantóide de ovos embrionados de galinha

Abstract

The Modified Vaccinia virus Ankara (MVA), which belongs to the family Poxviridae, was obtained after 570 passages in primary culture of cells chicken embryo fibroblast (CEFs) to be used as a vaccine in the global campaign to eradicate smallpox. Poxvirus based vaccines are a solo historical total success in the control of smallpox, which was officially declared eradicated in 1980 after the use of vaccinia virus in vaccines. Currently there is extensive experimental verification that explores the possibility of inserting the MVA vaccine platforms due to its virulence and vaccine safety. For this reason, the aim of this study was to determine an appropriate system for propagation of the virus for vaccine production. The prospect was to compare the efficiency of multiplicative MVA in two systems: primary culture of fibroblast cells versus chicken embryo chorioallantoic membrane (CAM) of embryonated chicken eggs. Whereas it is extremely advantageous from an economic standpoint, viral multiplication in MCA. The titration results showed that the virus multiplies efficiently in both culture systems and obtaining high virus titers is inversely proportional to the title infection. And in addition to the titration data, viral multiplication in MCA was determined by quantification of fluorescence through images obtained by confocal microscopy. The results showed a decrease in fluorescence intensity which occurs as increased time of infection. It was also defined viral productivity and observed the presence of pocks (injuries) infections between 101-108 PFU in MCA. Both the presence of pocks as obtaining high virus titers were demonstrated in infections in up to 104 PFU. The sample pocks produced by MVA were compared with the production of pocks on two other samples of Vaccinia virus: Western Reserve (prototype of the Poxviridae family) and Lister (comp most used worldwide for vaccine production during the program worldwide eradication of smallpox). The sample produced pocks large VACV-WR, Lister, whereas the sample produced lesions intermediate between MVA and VACVVACV- WR.