Trials for increasing the infectivity titer of fowl pox vaccines prepared on SPF embroynated chicken egg and tissue culture

Abstract

The present work was designed to study the effect of DEAE-dextran and Magnesium Chloride (MgCl) on fowl pox virus vaccine (FPV) in order to obtain a maximum titer allowing the massive production of the vaccine. Fowl pox virus; used for vaccine production; was propagated on embroynated chicken eggs (ECE) and chicken embryo fibroblast (CEF), the virus was inoculated in ECE and CEF without DEAEdextran nor MgCl, and with DEAE-Dextran and MgCl separately. The time of harvestion was early as one day post inoculation in CEF. The virus titer were higher in case of treated inoculums with DEAEdextran and MgCl reaching (6.2 and 7.5 log 10 TCID 50 /ml respectively) on CEF and (6.2 and 6.7 Log 10 EID 50 respectively) on ECE. Fowl pox vaccines (FPV) were prepared before and after DEAE-Dextran and MgCl treatment. The application of quality control assays revealed the safety, sterility and potency of the prepared vaccines. Immune response of the prepared FPV vaccines were evaluated in chickens using virus neutrization test (VNT). It was found that, the use of DEAE-Dextran and MgCl with the recommended concentrations could result in increasing the virus titer with reduction in the time of harvestation and accordingly increase the vaccine production and decrease its cost.

Baby Grivet Monkey Kidney (BGM) a new cell line for adaptation of fowl pox virus

“…In CEF, gradual increase in the titer had occurred and reached 10 5.7 TCID50/ml by the 7 th passage, and reached the highest titer of the virus 10 6.5 TCID50/ml by the 9 th passage and persisted stable in the 10 th passage. These findings were correspondent to that of Koehler and Schwoebel (1956), Namaa (1998) and Omar et al, (2014), who studied the propagation of fowl pox virus in chicken embryo fibroblast cell cultures and found that there was coincidence between the increase in virus titer and the cytopathic effect and the titers were relatively similar to those in infected chicken embryos.…”