Role of proteins MRP8 (S100A8) and MRP14 (S100A9) in the development of critical condition in patients with pneumonia with A/H1N1 influenza

Background. Today, the critical care medicine is actively developing, and rapid progress is closely related to the achievements of molecular biology, immunology, and pathological physiology. The study of the role of individual molecular structures in the realization of the reactions of innate and adaptive immunity, which underlie the pathogenesis of critical conditions, is an urgent scientific direction and is of interest.Aims. To assess the contribution of the protein complex MRP-8/14 to thedevelopment of systemic inflammation by determining its plasma concentration in patients with pneumonia with influenza A/H1N1.Materials and methods. 85 patients with pneumonia associated with influenza A/H1N1 were examined. Of these, 30 patients with severe pneumonia, 55 with non-severe pneumonia. The plasma concentration of the S100A8/A9 protein complex (MRP-8/14) was determined by flow cytometry on an analyzer (Beckman Coulter, USA).Results. It was found that in patients with severe pneumonia with influenza A/H1N1, the concentration of MRP-8/14 increased in 1.9 times compared with healthy. At the same time, in patients with severe pneumonia with influenza A/H1N1 with a fatal outcome, the concentration of MRP-8/14 increased in 2.1 times.Conclusion. An increase in the level of MRP-8/14 in patients with severe pneumonia associated with influenza A/H1N1, on the one hand, reflects the severity of the course of systemic inflammation, on the other hand, the molecules MRP-8 and MRP-14, acting as damage-associated molecular patterns (DAMPs) stimulate a pro-inflammatory response and contribute to the development of critical state. Thereby, the protein complex MRP-8/14 can be considered as a potential point of application of pharmacological action in the intensive care of critical conditions.