Сomparative analysis of cytokine determination in neutrophil supernatants stimulated by S. aureus supernatants with and without the SPA gene

Abstract

This study presents the results of the determination of cytokines by multiplex analysis in the blood neutrophil supernatants of donors stimulated by Staphylococcus aureus supernatants, depending on the presence or absence of the staphylococcal protein A (spa) gene in bacteria. Cytokine indication was carried out by multiplex analysis using BioRad kits (USA) for the determination of 17 human cytokines (G-CSF, GM-CSF, INF-γ, TNF-alfa, MCP-1, MIP-1beta, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-7,IL-8, IL-10, IL-12p70, IL-13, IL-17A) after 1 hour incubation of staphylococcal supernatants with neutrophils. It was shown that S. aureus, which had the staphylococcal protein A (spa) gene, significantly stimulated the secretion of neutrophils G-CSF (growth factor), IL-12p70, IL-17A, IFN-gamma, IL-13, IL-1b, IL-4, IL-6, IL-7, TNF-alfa (proinflammatory cytokines), MCP-1 (chemokine). But at the same time, they significantly reduced the secretion of IL-10 (anti-inflammatory cytokine), IL-8, MIP-1beta (chemokines). S. aureus supernatants, which did not have spa, also acted almost identically. IFN-gamma increased less significantly under their action, and IL-1b, on the contrary, more significantly compared to S. aureus supernatants having the staphylococcal protein A gene. It was found that the supernatants of all studied clinical isolates of S. aureus with a pronounced ability to produce cytokine-like substances, regardless of the presence/absence of the spa gene, affect the ability of neutrophils to secrete cytokines. Thus, the presence of cytokine-like activity in S. aureus affects the response of neutrophils to secrete a pool of cytokines upon contact of phagocytic cells with staphylococcal supernatants. In particular, pro-inflammatory interleukins, some chemokines and growth factors. This indicates that the interaction of neutrophils with extracellular cytokine-like products of S. aureus can significantly modulate the inflammatory process.