The differential gene expressions of rat mucosa colonized with single or multi-species of MRSA or PA were studied using RNA-sequencing of total transcriptome.

The differential gene expressions of rat mucosa colonized with single or multi-species of MRSA or PA were studied using RNA-sequencing of total transcriptome. In multi-species in-vitro biofilms PA partially inhibited SA growth. However, no significant inhibition of MRSA was detected during in-vivo colonization of multi-species in rat bullae. A total of 1797 genes were significantly (p < 0.05) differentially expressed in MRSA or PA or MRSA+PA colonized rat middle ear mucosa with respect to the control. The poly-microbial colonization of MRSA and PA induced the differential expression of a significant number of genes that are involved in immune response, inflammation, signaling, development, and defense; these were not expressed with single species colonization by either MRSA or PA. Genes involved in defense, immune response, inflammatory response, and developmental process were exclusively up-regulated, and genes that are involved in nervous system signaling, development and transmission, regulation of cell growth and development, anatomical and system development, and cell differentiation were down-regulated after multi-species inoculation.本研究通过全转录组RNA测序（RNA-sequencing），分析了单一或多菌种（耐甲氧西林金黄色葡萄球菌（Methicillin-resistant Staphylococcus aureus, MRSA）、铜绿假单胞菌（Pseudomonas aeruginosa, PA））定植的大鼠黏膜的差异基因表达情况。在多菌种体外生物被膜中，PA可部分抑制金黄色葡萄球菌（Staphylococcus aureus, SA）的生长。然而，在多菌种定植的大鼠中耳鼓泡体内模型中，未检测到对MRSA的显著抑制作用。与对照组相比，MRSA单独定植、PA单独定植或MRSA与PA联合定植的大鼠中耳黏膜中，共有1797个基因呈现显著差异表达（P < 0.05）。MRSA与PA的多菌种定植可诱导大量参与免疫应答、炎症反应、信号传导、发育及防御过程的基因发生差异表达；而MRSA或PA单独定植时，此类基因均未出现表达变化。多菌种接种后，参与防御、免疫应答、炎症反应及发育过程的基因均呈特异性上调；而参与神经系统信号传导、发育与传递、细胞生长与发育调控、解剖结构与系统发育以及细胞分化的基因则呈下调表达。