Taxonomic characterization of bacterial DNA isolated from blood clots of patients with ischemic stroke
Authors: Korchagin V.I. ,   Central Research Institute of Epidemiology, the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Moscow, Russian Federation, Kulikova N.G. , Komarova А.G. , Mironov К.О. , Gaponova I.I. , Krivosheeva N.М. , Ploskireva А.А. , Maleev V.V. ,   Central Research Institute of Epidemiology, the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Moscow, Russian Federation,   S.P.Botkin City Clinical Hospital, Moscow, Russian Federation,   Central Research Institute of Epidemiology, the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Moscow, Russian Federation,   Central Research Institute of Epidemiology, the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Moscow, Russian Federation,   S.P.Botkin City Clinical Hospital, Moscow, Russian Federation,   Central Research Institute of Epidemiology, the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Moscow, Russian Federation,   Pirogov Russian National Research Medical University, Moscow, Russian Federation,   Central Research Institute of Epidemiology, the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Moscow, Russian Federation
Published: July 2024

There is evidence of the role of microorganisms in endothelial damage and, as a consequence of activation of blood coagulation pathways, thrombosis, which in turn is one of the risk factors for the development of acute cerebrovascular accidents (ACVA). Objective. To analyze the microbiological profile of DNA isolated from thrombus of patients with ACVA. Materials and methods. Fifty-seven thrombus samples obtained lifetime from the vessels of patients with ischemic-type ACVA during thrombectomy and thrombaspiration were selected for the study. All patients with ACVA were in the period of coronavirus infection reconvalescence. Twelve blood samples from patients without infectious diseases were used for comparison. Amplification of DNA isolated from biological material was performed using primers specific to the 16S rRNA gene fragment. The obtained PCR products were sequenced by Sanger sequencing method, with subsequent processing of chromatograms in the BCV package. RDP Classifier was used to determine the taxonomic affiliation of DNA sequences. Statistical analysis was performed in the R environment using Pearson's and Fisher's χ2 criteria. Test results were considered significant at p < 0.05. Results. Using the RDP Classifier, the taxonomic affiliation of 16S rRNA gene fragment amplification products were determined for 43 blood and clot samples. DNA of Actinobacteria and Firmicutes taxa were most represented in the clot samples of patients with ACVA. Of the Firmicutes and Proteobacteria taxa, Firmicutes predominated in thrombi, whereas Proteobacteria predominated in blood. The obtained data are consistent with the data on the key role of systemic intestinal inflammation in the pathogenesis of ACVA. Conclusion. DNA fragments of Actinomycetales, Bacillales, and Clostridiales bacteria found in thrombi of patients with ACVA indicate that they can penetrate the damaged epithelial barrier and promote platelet aggregation and thrombus formation, increasing the risk of ischemic stroke. Key words: ischemic stroke, acute cerebral circulatory disorders, bacterial infection, RDP Classifier