Abstract
Background. The high systemic toxicity of modern chemotherapeutic agents necessitates the search for effective and safe biogenic cytoprotectors. In biology, fetal animal sera are considered classic cytoprotectors. Umbilical cord blood serum is a promising analog of fetal sera, but its utilization requires the development of effective preservation methods. Objective. The aim of this work was to evaluate the cytoprotective effect of lyophilized and frozen human umbilical cord blood serum. Materials and Methods. The study was conducted on the L929 fibroblast cell line. Chemically induced toxicity was modeled by culturing the cells with doxorubicin (2 µg/mL), cisplatin (25 µg/mL), and cyclophosphamide (1mg/mL) for 24 hours. The cytoprotective effect of 10% cord blood serum, either frozen at -20°C or lyophilized, was investigated. Culture status was assessed using light microscopy, the MTT assay, and flow cytometry (Annexin V-FITC/7-AAD staining). Results. The cytostatic agents significantly altered monolayer morphology, reduced cell viability, and initiated apoptosis (particularly doxorubicin and cisplatin). In the cisplatin-induced toxicity model, the introduction of both types of sera resulted in the complete neutralization of the toxic effect. Under doxorubicin exposure, the sera significantly reduced apoptosis levels and improved monolayer morphology. The in vitro effect of cyclophosphamide manifested as a moderate inhibition of proliferation, which was completely overcome by the addition of the sera. No statistically significant differences were found between the biological activities of the frozen and lyophilized sera. Conclusions. Lyophilized umbilical cord blood serum fully retains the cytoprotective potential of native frozen serum. It effectively protects L929 cells from the toxic effects of chemotherapeutic drugs (especially cisplatin), which justifies further research into its potential application as a supportive therapy agent in oncology and regenerative medicine.