pneumoniae-infected human alveolar epithelial carcinoma A549 cell secretome, in an effort to provide a better view of host-pathogen interaction and identify novel molecules/biomarkers check details for M. pneumoniae infection. As reported here, we have identified 113 proteins affected by M. pneumoniae infection. Furthermore, we evaluated the clinical application of one identified protein, IL-33, as a “proof of concept” example, and the result showed that it could help to distinguish M. pneumoniae pneumonia (MPP) patients from non-M. pneumoniae patients. Results Label-free quantitative shotgun proteomic analysis of cell secretome

upon M. pneumoniae XAV-939 solubility dmso infection The study design is outlined in Figure 1. Both cell viability and apoptosis

assay revealed that serum free medium (SFM) did not significantly affect cell integrity and secretion capacity within 24 h (see Additional files 1 and 2: Figures S1 and S2), and thus serum-free culture for 24 h was chosen as the time point for secretome collection. Figure 1 Workflow chart of the experimental design. Based on the LC-MS/MS data, 233 proteins were identified in control A549 cells, with 187 being identified from all three biological replicates (see Additional file 3: Figure S3A), indicating a relatively good reproducibility. Similarly, 237 proteins were identified in M. pneumoniae-infected A549 cells, with 199 being identified from all three biological replicates (see Additional file 3: Figure S3B). Thus, a total of 256 proteins were identified, among which 214 proteins were detected in both groups, with 19 and 23 proteins being uniquely secreted by control cells and M. selleck kinase inhibitor pneumoniae-infected cells, respectively (see Additional file 3: Figure S3C). Complete protein identification lists for control and M. pneumoniae-infected cells were provided in Additional files 4 and 5: Datasheet S1 and Table S1. For

the selleckchem identified proteins, label-free quantitative comparison performed by DeCyder™ MS Differential software revealed that 113 proteins were significantly affected by M. pneumoniae infection (fold difference ≥1.5 or ≤0.67) (see Additional file 6: Table S2). Specifically, there were 65 up-regulated and 48 down-regulated proteins in M. pneumoniae-infected A549 cells, among which 10 were uniquely expressed in M. pneumoniae-treated A549 and 9 in control A549 cells. For all 113 differential proteins, the number of peptides for each protein used for quantification varied from 1 to 13. Among them, 33 proteins were quantified on the basis of two or more peptides, with average coefficient of variation (CV) of the fold changes for peptides as 16.80% (range from 0.00% to 39.21%, see Additional file 6: Table S2), demonstrating a rational reproducibility of the quantitative data. The rest 80 proteins were quantified with only one peptide by the DeCyder software. Validation of proteins with changed expression during M.