Caracterização da atividade biológica de citocinas recombinantes de hamster sírio dourado (Mesocricetus auratus)

Abstract

The golden Syrian hamster (Mesocricetus auratus) has been established as a relevant experimental model for studies on infections, inflammation, and cancer. However, the limited availability of specific immunological reagents, such as those for cytokine detection, hampers the advancement of immunological characterization in this species. This study aimed to evaluate the biological activity of the recombinant cytokines rIL-6, rIL-10, rIFN-γ, rTGF-β, and rTNF-α, produced in Escherichia coli, with the objective of enabling their application as components of detection kits and immunological tools for the Syrian hamster. The proteins were expressed, purified, subjected to endotoxin removal, and characterized by SDS-PAGE and Western blotting. Biological activity was evaluated through a cell viability assay (MTT) in CHO-K1 cells and by gene expression analysis using RT-qPCR. The MTT assay revealed that within the first 24 h, all cytokines - except rIFN-γ - induced a significant proliferative effect on CHO-K1 cells. From 48 h onward, a progressive reduction in cell viability was observed for all cytokines. RT-qPCR analysis demonstrated that treatment with rIL-6 significantly downregulated tnf-α expression without inducing il-10 transcription. Exposure to rIL-10 resulted in decreased expression of tnf-α and ifn-γ, and did not induce il-6. Similarly, treatment with rTGF-β reduced tnf-α and ifn-γ levels, also without detection of il-6 or il-10. Stimulation with rIFN-γ led to a reduction in tnf-α, but did not significantly modulate tgf-β expression, nor did it induce transcription of il-6 or il-10. Overall, these findings demonstrate that recombinant cytokines from the golden Syrian hamster exhibit functional biological activity. This evidence reinforces the potential of these proteins as valuable tools for immunological assays, contributing to the development of specific reagents and enhancing the applicability of the Syrian hamster as an experimental model across diverse fields of scientific research.