The Impact of Residual Antibacterial Agents in Quail Embryos on the Morphofunctional Characteristics of the Cell Monolayer as a Substrate for Virus Cultivation

Introduction. Cell cultures derived, in particular, from quail embryos serve as a critically important and widely used substrate for viral cultivation in vaccine manufacturing. Therefore, any deviation in the quality of this biological substrate poses a direct threat to the efficacy and safety of the final medicinal product. The article examines the effect of residual ciprofloxacin accumulated in quail embryos on the morphofunctional properties of the monolayer used as a substrate for viral cultivation. The aim of the study is to substantiate criteria for the selection of biological raw materials in order to enhance the safety and efficiency of viral vaccine production. Materials and methods. The study includes the identification and quantitative determination of an antibacterial drug in quail eggs using the enzyme-linked immunosorbent assay (ELISA) method, the isolation of a primary cell culture from quail embryos by means of trypsinization, as well as the assessment of the obtained monolayers by light microscopy and the evaluation of the specific activity of the mumps virus through titration. The materials used in the study included fertilized incubated quail eggs obtained from a treated parent flock on the 13th and 31st days after treatment (experimental and control groups, respectively), phosphate-buffered saline and glucose solution, trypsin, and a nutrient medium for mumps virus cultivation. Results. A primary trypsinized cell suspension derived from quail embryos was obtained and subsequently used to produce a monolayer serving as a substrate for mumps virus cultivation. A comparative analysis of the morphological characteristics of the monolayers and the specific activity of the mumps virus in each of them confirmed the negative effect of residual amounts of the antibacterial agent in quail eggs on the morphofunctional characteristics of the cellular monolayer as a substrate for virus cultivation. Сonclusion. The residual amount of the antibacterial agent induces destructive cellular changes, reduces cell adhesive properties and viability, thereby impairing viral replication. The obtained data are consistent with current understanding of the cytotoxic effects of ciprofloxacin and further substantiate the necessity of incorporating residual antibacterial agent testing into the incoming raw material quality control algorithm.