Changes of the effector functions of the γ-globulin fraction proteins and of their metal complexes due to equimolar binding by Staphylococcus aureus protein A
AbstractIntroduction. Specific binding of S. aureus protein A with Fc-fragment of human IgG in a context of possibility of its functioning as soluble Fc-receptor was considered.
Aim – evaluation of cytokine production by human blood cells in presence of human serum γ-globulin and of its metal complexes during equimolar binding them by S. aureus protein A.
Material and methods. The work was made on human peripheral blood cells with use of methods of preparational biochemistry and protein chemistry, of optico-physical and immunochemical methods, of the technologies of cytokine induction.
Results. It has been shown that S. aureus protein A interacted equimolarly with human serum γ-globulin and bound its Fc-fragment that led to formation of characteristical complex and to decrease in induction by γ-globulin of the production of IL-1β, IL-6, TNF-α and IL-10 by human blood cells. Formation of γ-globulin metal complexes caused conformational changes of the protein molecule that led to partial decrease in efficiency of binding the ligand by S. aureus protein A.
Conclusion. Formation of the γ-globulin metal complexes decreased efficiency of its equimolar binding by S. aureus protein A and limited the blocking in mechanisms of cytokine induction activated by interaction of the cell Fc-receptors with specific ligand.
Keywords: γ-globulins; metal complexes; S.aureus protein A; binding; Fc-receptors; cytokines
For citation: Cheknev S.B., Sarycheva M.A., Vostrova E.I., Babajanz A.A. Changes of the effector functions of the γ-globulin fraction proteins and of their metal complexes due to equimolar binding by Staphylococcus aureus protein A. Immunologiya. 2025; 46 (2): 161–70. DOI: https://doi.org/10.33029/1816-2134-2025-46-2-161-170 (in Russian)
Funding. The study was performed in the frame of State task of the Ministry of Health of the Russian Federation «Elaboration of drugs for treatment of metabolic syndrome and for normal microflora state correction with use of polyisoprenoids’ products» dated December 27, 2017 (state registration N 118032390189-1). Open publication is allowed.
Conflict of interests. Authors declare no conflict of interests.
Authors’ contribution. Formulation of the tasks, methodology, preparational biochemistry and protein chemistry, analysis of the results, the text of the work – Cheknev S.B.; preparational biochemistry and protein chemistry, spectrophotometry, immunochemistry – Sarycheva M.A.; immunochemistry – Vostrova E.I.; cell technologies, induction of cytokines – Babajanz A.A.