Transcriptome analyses of Staphylococcus aureus grown in platelet concentrates with focus on virulence

Bacterial contamination of platelets is the major cause of post-transfusion septic reactions. Bacteria are introduced into the donated blood during venipuncture and are present predominantly in platelet concentrates as this product is susceptible to bacterial proliferation due to their storage conditions. Skin and mucosa flora including the super bug Staphylococcus aureus are predominant platelet contaminants. Despite all the strategies implemented to mitigate the risk of transfusing platelets contaminated with bacteria, Staphylococcus aureus often escapes detection causing septic transfusion reactions. Missed detection of this organism during platelet screening is attributed to slow growth and formation of aggregates that adhere to platelets and platelet bags. I hypothesize that aggregate formation by Staphylococcus aureus in platelets results in increased pathogenicity and antibiotic resistance which are harmful to platelet recipients. My PhD proposal aims to investigate gene expression of Staphylococcus aureus when grown in platelets. Using microbiological, biochemical and molecular biology techniques, I will validate the gene expression results. Ultimately, my investigation will shed light on the factors contributing to missed detection of Staphylococcus aureuswith the long-term goal of improving the safety of transfusable blood components. My PhD project relates to the research priority of 'Minimizing the adverse effects of blood product transfusion'.

RAMIREZ-ARCOS, Sandra

Canadian Blood Services

Graduate Fellowship Program

Ontario

$122,000