Background A growing number of severe pneumonia (MPP) cases have already been reported recently. and could reach 50 to 80% before regional outbreak [1, 2]. MPP is referred to as gentle and self-limited usually; however, increasingly more serious and even fatal instances of MPP with serious complications such as for example pulmonary necrosis and chronic interstitial fibrosis have already been reported lately [3C5]. Macrolide-resistant and extreme immunological inflammation are generally within serious MPP  also. Therefore, it is vital for pediatricians to identify serious MPP early, address it promptly, and stop the development of the condition effectively. However, the system and etiology of severe MPP are largely unknown. Based on published hypotheses, severe MPP is considered as a hyper-immune response that originates from repeated or longer lasting childhood MP infections in the lung ; further, severe MPP can be an overactive innate immune response such as macrophage activation via heterodimerization of Toll-like receptors two and six of the bronchoepithelial cells to lipoproteins . With ELISA and real-time quantitative PCR techniques, researchers have found that the cell-mediated immune response plays an important role in the pathogenesis of MPP [9C11] but the role of humoral-mediated immune response in moderate and severe MPP is still unclear. High-throughput RNA sequencing technology, so called next-generation sequencing, revolutionarily enhanced our understanding around the complexity of eukaryotic transcriptome [12, 13]. It has several key advantages including being independent around the predetermined genome sequences, highly accurate in detecting gene expression with very wide dynamic detection ranges with low background. Thus, RNA sequencing is not only useful to precisely determine gene expression profiles but also particularly powerful to detect novel transcription variants via alternative splicing . In the present study, we observed the transcriptome of bronchoalveolar lavage fluid (BALF) from children with moderate MPP and severe MPP. The large sum of novel information around BIBR 953 the gene expression profiles as well as novel transcripts through alternative splicing would provide not only insights into the pathogenesis of severe MPP but also as basis for the development of biomarkers and therapeutic targets. Methods Study subjects The current study was conducted at the First Hospital of Jilin University (Changchun City, Jilin Province, Peoples Republic of China). Six newly diagnosed children (three male and three female) with acute stage of MPP admitted to our hospital were recruited [see Additional file 1: Table S1]. All of the children enrolled in this study had no recurrent severe or unusual infections and had no inflammatory disorders or autoimmunity. Therefore, based on the published diagnostic criteria, they had no history of common variable immunodefiency (CVID) . After admission to Rabbit Polyclonal to IL18R. our hospital, the known degrees of immunoglobulins in the bloodstream of the kids have been examined; the known degrees of IgG, IgA, and IgM have been discovered within regular range released for kids [see Additional document 2: Body S1] . Lymphocyte information in the peripheral bloodstream of the kids have been analyzed also, the cell percentage and amounts of T cells, B cells, and organic killer cells have been discovered within regular range [discover Additional document 3: Desk S2] . As a result, the enrolled kids have been excluded from having CVID, autosomal recessive agammaglobulinemia , or high IgM symptoms . All small children didn’t have got neglected metabolic/congenital systemic diseases. The medical diagnosis of pneumonia was predicated on scientific manifestations (cough, fever, productive or dry sputum, dyspnea, unusual breathing sound, radiological pulmonary abnormalities). The medical diagnosis of (MP) infections was predicated on positive results of serologic test (MP-IgM test 1:40) and positive results of MP DNA (>500 copy/L) in BALF with real-time quantitative PCR. MP was the only pathogen identified in all the MPP subjects. The moderate and severe community-acquired pneumonia was defined based on BIBR 953 the criteria described [17, 18]. Mild group was defined as fever <38.5?C at any age, tachypnea but respiratory rate <70 breaths/min at age <3?years old or <50 breaths/min at age 3?years old, normal food-intake, and BIBR 953 no dehydration. Severe group was defined as fever BIBR 953 38.5?C at any age, breathless with respiratory rate 70 breaths/min at age <3?years old or 50 breaths/min at age 3?years old (excluding the reason why of fever and cry), cyanosis, marked retractions, anorexia, and dehydration. The created informed consents had been obtained by caution givers of most.