Transcriptomic analysis of differential gene expression in staphylococcus aureus-induced pneumonia in pediatrics based on microarray analysis

Staphylococcus aureus is a leading cause of about 80% of infections in humans and up to 60–70% of hospital-acquired infections. Pneumonia is the broad term for a range of disorders that result in infection of the lung parenchyma and are caused by a number of organisms. It is a common disease that affects people from all walks of life. Identification of an etiologic agent for pneumonia is critical in order to provide appropriate therapy and maintain epidemiological records. Study on the transcriptional profiling of patients infected with S. aureus is a pivot to the analysis of differentially expressed gene in the blood of patients infected with S. aureus. This study performed the analysis of gene expression dataset GSE30119 available on the Gene expression Omnibus (GEO) which is based on the hypothesis tested that patient clinical heterogeneity will be reflected in transcriptional profile heterogeneity. The study comprised 143 pediatric patients, with 44 healthy individuals, 81 pneumonia-free, and 18 pneumonia infection patients. We discovered a total of 54 genes related to S. aureus infection and 612 genes associated with Pneumonia. According to Gene Ontology (GO) functional and pathway enrichment studies, the S. aureus infection associated genes are predominantly engaged in the innate immune response, calcium-mediated signaling, Neutrophil extracellular trap formation, Formation of Fibrin Clot (Clotting Cascade). Whereas the genes associated with Pneumonia are enriched in adaptive immune response, inflammatory, Interferon alpha/beta signaling, TCR signaling, Gα(i) signalling events. This study shows differentially expressed genes and their biological activities in relation to S. aureus infection and Pneumonia, and it may provide more light on the underlying molecular mechanisms and possibly important gene signatures in Pneumonia development.