Presenter of 1 Presentation
COMBINING TWO RELATED DNA BIOMARKERS TO STRATIFY PATIENTS FOR PRECISE MEDICINE IN STROKE
Abstract
Background and Aims
CpG-enriched extracellular DNA (exDNA) fragments in plasma belong to signal molecules that bind TLR9 to activate NFkB-mediated inflammaton. Genetic polymorphism of TLR9, the exDNA receptor, associates with multiple organ failure developments and lethal outcomes of post-trauma and sepsis patients. We hypothesize that the genetic variant of TLR9 (rs352162), linked to better proinflammatory signaling in response to DNA ligand, predisposes most to the unfavorable course and outcome of stroke in a cohort of patients exhibiting an increased concentration of exDNA in circulation. Thus, the study aimed to assess whether combining the TLR9 genetic marker and determining the exDNA concentration may better select a cohort of patients in whom exDNA-receptor signaling contributes most to the course of a stroke.
Methods
ExDNA was isolated from plasma of 138 patients with stroke using organic solvents, and SYBR Green determined the concentration. Genotyping of allelic variants of the TLR9 rs352162 gene was performed using a PCR and designed allele-specific tetra primers followed by electrophoretic separation of the products. Statistical significance between groups of patients was performed by the t-test, Fisher test, Mann-Whitney test, and One-way ANOVA.
Results
TLR9 CC carriers exhibited a more severe course of the disease. ExDNA >300 ng/ml associated with increased odds ratio values for infection and 30-day lethality in TLR9 CC-positive stroke patients versus patients with TLR9 CT and TT genotypes (OR=63 vs. OR=6,145, P<0.001 and P=0.007, respectively).
Conclusions
Determining both exDNA concentration and TLR9 genetic polymorphism might aid in selecting patients who may benefit most from inhibitingTLR9 signaling and /or exDNA extracorporeal sorption.