Soluble B7-H3 elevations in hospitalized children with Mycoplasma pneumoniae pneumonia

Kukoamine A Improves Mycoplasma pneumoniae Pneumonia by Regulating miR-222-3p/Superoxide Dismutase 2

Mycoplasma pneumoniae pneumonia (MPP) represents a common respiratory disease in children patients. Kukoamine A (KuA) is a spermine alkaloid found in the Chinese herb Cortex Lycii radices, which has a variety of pharmacological properties. However, no study has been reported on the role of KuA in MPP. Exosomes, a type of lipid bilayer-enclosed extracellular vesicles, can be delivered to the target cells, where they regulate function and physiology. With the use of human alveolar basal epithelial cells (HABECs) as an in vitro model, in this study, we sought to characterize the changes in levels of superoxide dismutase 2 (SOD2) and proinflammatory cytokines including IL-6 and TNF-α in HABECs in response to exosomes, which were isolated from peripheral blood serum of MPP patients. We found that, compared to normal, MPP patients exhibited a significant up-regulated miR-222-3p. Further, exosomal miR-222-3p downregulated SOD2 activity but promoted nuclear NF-κB activity and expression of IL-6 and TNF-α in HABECs, ultimately leading to an oxidative stress condition. Interestingly, such stimulating effects were attenuated by the pretreatment of KuA. This study suggests a critical role possessed by KuA in MPP by regulating the miR-222-3p/SOD2 axis, which represents a promising strategy for the treatment of MPP.

Related Markers for the Precision Diagnosis of Complex Appendicitis in Children

Acute appendicitis is the most common surgical emergency in children. Despite the high incidence rate of appendicitis, it is sometimes misdiagnosed or missed. Complex appendicitis (CA) in children is characterized by a critical condition, several complications, and high mortality. Precision distinguishing between simple appendicitis and CA correctly is key to choosing appropriate treatment. A safe, cheap, rapid, extensive and accurate diagnostic marker of appendicitis will be of great significance for emergency general surgeons to treat suspected CA. Many studies have investigated possible diagnostic markers for the diagnosis of CA in children. In this study, studies related to CA in children in recent years are summarized, and the related markers and scoring system for the diagnosis of CA in children are summarized.

Identification of Pan-Cancer Biomarkers Based on the Gene Expression Profiles of Cancer Cell Lines

There are many types of cancers. Although they share some hallmarks, such as proliferation and metastasis, they are still very different from many perspectives. They grow on different organ or tissues. Does each cancer have a unique gene expression pattern that makes it different from other cancer types? After the Cancer Genome Atlas (TCGA) project, there are more and more pan-cancer studies. Researchers want to get robust gene expression signature from pan-cancer patients. But there is large variance in cancer patients due to heterogeneity. To get robust results, the sample size will be too large to recruit. In this study, we tried another approach to get robust pan-cancer biomarkers by using the cell line data to reduce the variance. We applied several advanced computational methods to analyze the Cancer Cell Line Encyclopedia (CCLE) gene expression profiles which included 988 cell lines from 20 cancer types. Two feature selection methods, including Boruta, and max-relevance and min-redundancy methods, were applied to the cell line gene expression data one by one, generating a feature list. Such list was fed into incremental feature selection method, incorporating one classification algorithm, to extract biomarkers, construct optimal classifiers and decision rules. The optimal classifiers provided good performance, which can be useful tools to identify cell lines from different cancer types, whereas the biomarkers (e.g. NCKAP1, TNFRSF12A, LAMB2, FKBP9, PFN2, TOM1L1) and rules identified in this work may provide a meaningful and precise reference for differentiating multiple types of cancer and contribute to the personalized treatment of tumors.

Deregulated Expression of miR-483-3p Serves as a Diagnostic Biomarker in Severe Pneumonia Children with Respiratory Failure and Its Predictive Value for the Clinical Outcome of Patients

Severe pneumonia in children is a group of inflammatory diseases of respiratory tract caused by pathogenic microorganisms. Increasing evidence suggested the crucial effects of microRNA on inflammatory diseases. This study aimed to reveal the expression and role of miR-483-3p in the serum of children with severe pneumonia, and to explore the effect of miR-483-3p on the biological function of lipopolysaccharide (LPS)-induced MRC-5 cells. MRC-5 cells were disposed with LPS to construct an in vitro pneumonia cell model. The relative expression level of miR-483-3p was measured by qRT-PCR. ROC curve was used to evaluate the diagnostic value of miR-483-3p in severe pneumonia. The Kaplan-Meier curve was performed to test the characteristics of survival distribution of different miRNA classifications. Cell viability and apoptosis were performed by CCK-8 assay and flow cytometry. IL-1β, TNF-α, and IL-6 were detected by ELISA. Luciferase reporter gene assay and western blot analysis were performed to detect the interaction between miR-483-3p and IGF-1. The expression of serum miR-483-3p in severe pneumonia patients was higher than in controls. The AUC value of the ROC curve was 0.919, indicating that miR-483-3p had diagnostic value for severe pneumonia. The survival curve showed that patients with high expression of miR-483-3p had higher mortality. Cell viability and apoptosis assay showed that overexpression of miR-483-3p suppressed cell proliferation and promoted apoptosis. And upregulation of miR-483-3p promoted generation of inflammatory cytokines. Luciferase report gene assay and western blot assay both illustrated that IGF-1 might be the target gene of miR-483-3p. Serum miR-483-3p can be used as a biomarker for the diagnosis of severe pneumonia. High expression of miR-483-3p promoted the development of severe pneumonia.

sB7H3 in Children with Acute Appendicitis: Its Diagnostic Value and Association with Histological Findings

Background

Several efforts have been made to find out a valuable marker to assist the diagnosis and differentiation of gangrenous/perforated appendicitis. We aimed to determine the diagnostic capacity of soluble B7H3 (sB7H3) in acute appendicitis (AA) and its accuracy as a predictor of the severity of appendicitis.

Methods

182 children were allocated into four groups as follows: control group (CG, 90), simple appendicitis (SA, 12), purulent appendicitis (PA, 49), and gangrenous appendicitis (GA, 31). Prior to appendectomy, blood was collected and sent for analysis of routine examination and cytokines (sB7H3 and TNF-α). We compared values of all measured parameters according to histological findings. Furthermore, we assigned AA patients into the nonperforated appendicitis group and the perforated appendicitis group. The diagnostic effects of significant markers were assessed by ROC curves.

Results

Only the levels of CRP, FIB, and sB7H3 had a remarkable rising trend in AA-based groups, while differences in the levels of CRP and FIB between simple appendicitis and purulent appendicitis were not statistically significant. In addition, sB7H3 was found as the only marker in children with AA, which was markedly associated with the degree of histological findings of the appendix. Furthermore, sB7H3 had a high diagnostic value in predicting AA and complex appendicitis (PA+GA) in children. However, the diagnostic performance of sB7H3 for distinguishing PA from GA was not remarkable. Additionally, only the levels of CRP and sB7H3 were statistically different between the nonperforated appendicitis group and the perforated appendicitis group. The diagnostic performance of CRP and sB7H3 could not merely predict perforation of AA in children; however, the diagnostic performance was improved after combination.

Conclusions

sB7H3 could be used as a valuable marker to predict the presence of AA and complex AA in children. However, the diagnostic value of sB7H3 to predict gangrenous/perforated appendicitis was not found to be remarkable. The combination of sB7H3 and CRP might improve the prediction of perforated appendicitis.

B7-H3 Immune Checkpoint Protein in Human Cancer

B7-H3 belongs to the B7 family of immune checkpoint proteins, which are important regulators of the adaptive immune response and emerging key players in human cancer. B7-H3 is a transmembrane protein expressed on the surface of tumor cells, antigen presenting cells, natural killer cells, tumor endothelial cells, but can also be present in intra- and extracellular vesicles. Additionally, B7-H3 may be present as a circulating soluble isoform in serum and other body fluids. B7-H3 is overexpressed in a variety of tumor types, in correlation with poor prognosis. B7-H3 is a promising new immunotherapy target for anti-cancer immune response, as well as a potential biomarker. Besides its immunoregulatory role, B7-H3 has intrinsic pro-tumorigenic activities related to enhanced cell proliferation, migration, invasion, angiogenesis, metastatic capacity and anti-cancer drug resistance. B7-H3 has also been found to regulate key metabolic enzymes, promoting the high glycolytic capacity of cancer cells. B7-H3 receptors are still not identified, and little is known about the molecular mechanisms underlying B7-H3 functions. Here, we review the current knowledge on the involvement of B7-H3 in human cancer.

The diagnostic value of serological tests and real-time polymerase chain reaction in children with acute Mycoplasma pneumoniae infection

Background

This study set out to evaluate the clinical significance and diagnostic effectiveness of serological tests and real-time polymerase chain reactions (RT-PCR) in children of different age groups and disease durations infected with Mycoplasma pneumoniae (MP).

Methods

Pediatric patients with lower respiratory tract infection (LRTI) confirmed by polymerase chain reaction (PCR) were enrolled and subjected to bronchoalveolar lavage fluid PCR (BALF-PCR) for MP infection. The diagnostic values of the serum immunoglobulin M (IgM) test, paired sera immunoglobulin G (IgG) test, RT PCR applied to nasopharyngeal aspirates (NPA-PCR), and combined IgM and NPA-PCR test were evaluated.

Results

When BALF PCR was used as the gold standard, the MP positivity rate of combined IgM and NPA PCR was 78.85%in children aged 3–5 years. The positivity rates of IgM, NPA PCR, and combined IgM and NPA PCR in children older than 5 years were 71.21%, 72.72%, and 84.85%, respectively. The detection rate of combined IgM and NPA PCR was consistent with BALF PCR (Kappa =0.727). The MP positivity rates of combined IgM and NPA PCR at 1–2 weeks was as high as 91.11%, and was consistent with the BALF PCR (Kappa =0.756). Moreover, the positivity rates of IgM or NPA PCR at 2-3 weeks were 63.16%, and were consistent with each other (Kappa =0.771).

Conclusions

Combined IgM and NPA PCR is the optimal test to confirm MP infection among children aged 3–5 years in cases with a disease duration of less than2 weeks, and either NPA PCR or IgM is recommended for children older than 5 years with a disease duration of 2–3 weeks.

Keywords

Mycoplasma pneumoniae pneumonia (MPP); diagnosis; children; age; disease duration

High expression of miR-222-3p in children with Mycoplasma pneumoniae pneumonia

Objectives

Mycoplasma pneumoniae is a leading cause of community-acquired pneumonia in children. However, its mechanism of pathogenesis is not fully understood, and microRNAs might play a role. This study aimed to explore the microRNA-222-3p (miR-222-3p) expression and its possible role in children with M.pneumoniae pneumonia (MPP).

Methods

Thirty-six children with MPP and twenty-seven age-matched controls from Children’s Hospital of Soochow University were enrolled in this study. MiR-222-3p and cluster of differentiation 4 (CD4) mRNA were detected using real-time PCR in children’s peripheral blood plasma samples. THP-1 cells and mice were stimulated with M.pneumoniae lipid-associated membrane proteins(LAMPs).

Results

Children with MPP had significantly higher levels of miR-222-3p and lower levels of CD4 in peripheral blood plasma (P <  0.05). Additionally, Sixteen children with MPP complicated with pleural effusion had higher miR-222-3p levels than those without pleural effusion. MiR-222-3p or CD4 in THP-1 cells increased or decreased, respectively, in a dose dependent manner after LAMP stimulation. In LAMP-stimulated mice massive inflammatory cells infiltrates surrounded the bronchioles, and miR-222-3p increased in the bronchoalveolar lavage fluid. In conclusion, miR-222-3p was highly expressed in children with MPP, especially those with pleural effusion.

Conclusion

Small sample studies showed that M.pneumoniae or its LAMPs could increase miR-222-3p and decrease CD4 in macrophages,both in vitro and vivo.Thus, miR-222-3p might be an MPP biomarker for the diagnosis and prognosis.

Plasma soluble B7-H3 levels for severity evaluation in pediatric patients with Mycoplasma pneumoniae pneumonia

Seeking for the novel biomarkers for Mycoplasma pneumoniae pneumonia (MPP) could be not only helpful for disease diagnosis but also useful for treatment efficacy monitoring. The aim of present study was to evaluate the role of plasma soluble B7-H3 (sB7-H3) in MPP diagnosis and treatment efficacy prediction, and involvement of B7-H3 in MPP disease course. A total of 108 MPP patients and 40 control subjects were recruited into this study for changes of sB7-H3 levels in MPP. In addition, a mouse model of MPP was also established for confirmation of the involvement of sB7-H3 in MPP in vivo. Significantly increased levels of sB7-H3 were found in both mild and severe MPP patients compared to control patients. Moreover, significantly increased level of sB7-H3 was also found in severe MPP patients compared to mild subjects. The ROC curve showed sB7-H3 had severity prediction capacity in mild and severe MPP. Plasma sB7-H3 correlated positively with IFN-r and GM-CSF in mild or severe MPP patients. Moreover, significantly increased level of plasma sB7-H3 level were found in acute phase MPP patients compared to control subjects, whereas significantly decreased level of plasma sB7-H3 was found in recovery phase MPP patients compared to acute phase patients. In addition, decreased levels of sB7-H3 were found in mice from Dexamethasone group compared to LAMP group. Plasma sB7-H3 level might serve as biomarker for severity MPP prediction and treatment efficacy evaluation. Furthermore, direct involvement of B7-H3 was confirmed in vivo during the MPP disease course.

The role of miR-29c/B7-H3/Th17 axis in children with Mycoplasma pneumoniae pneumonia

Background

Mycoplasma pneumoniae (M. pneumoniae) is one of the most common causes of community-acquired pneumonia in children. Recent studies demonstrated that the incidence of severe or fatal M. pneumoniae was gradually increasing, which may be related to the excessive inflammation. However, the exact pathogenesis of excessive inflammation in Mycoplasma pneumoniae pneumonia(MPP) is still unclear. This study aimed to reveal the role of miR-29c/B7-H3/Th17 axis in children with MPP.

Methods

Children hospitalized in Respiratory Department during Jan. 2014 to Dec. 2015 were enrolled. All children enrolled was confirmed with MP infection using real-time PCR and ELISA. Children were excluded if they were co-infected with other pathogens. A total of 52 children with MPP and 26 controls were enrolled. miR-29c expression in monocytes of children with MPP was determined by real-time PCR and soluble B7-H3 (sB7-H3) and IL-17 were determined by ELISA, and explore their clinical significance. miR-29c overexpression and silencing technology and luciferase reporter assay were performed to confirm whether B7-H3 is the direct target of miR-29c. The levels of transcription factor ROR-γt in CD4+ T cells and cytokine IL-17A in supernatant were detected after stimulated by different concentrations of B7-H3 fusion protein in vitro.

Results

Of all 52 children with MPP, the mean age of the children were 77 ± 33 months, and 23 cases were male accounting for 44.2%. Nineteen cases had pleural effusion accounting for 36.5%. Children with MPP had significantly lower level of miR-29c and higher level of sB7-H3 and IL-17 compared to controls (both P < 0.05). The level of miR-29c significantly increased during convalescent phase compared to that of acute phase while sB7-H3 and IL-17 significantly decreased during convalescent phase (both P < 0.05). There was a positive correlation between the level of sB7-H3 and IL-17 in children with MPP during acute-stage (r = 0.361,P = 0.009). Children with MPP combined with pleural effusion had significantly higher level of sB7-H3 compared to those without pleural effusion (9952.3 ± 3065.3 vs. 7449.7 ± 2231.5, pg/ml), and the levels of sB7-H3 was positively correlated with the number of days of fever. The level of miR-29c was negatively correlated with M. pneumoniae specific IgG, IgM level. High concentrations of B7-H3(15μg/ml) could enhance ROR-γt expression and increase IL-17A. Functional studies based on luciferase reporter assay and immunofluorescence staining suggested that B7-H3 is the direct target of miR-29c, and miR-29c silencing or overexpression could up- or down-regulate the expression of B7-H3 in THP-1 cells.

Conclusions

The axis of miR-29c/B7-H3/Th17 plays a vital role in children with MPP through excessive inflammation. miR-29c and B7-H3 may be the new target for the prevention and treatment of MPP, and may be the novel and potential biomarkers for the assessment of prognosis.

Serum Tumor Necrosis Factor-α and Interferon-γ Levels in Pediatric Mycoplasma pneumoniae Pneumonia: A Systematic Review and Meta-Analysis

Background

Mycoplasma pneumoniae pneumonia (MPP) is one of the most common forms of community-acquired pneumonia in children. The objective of this study was to explore potential changes in levels of serum tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) associated with pediatric MPP.

Methods

This protocol has been registered (PROSPERO 2017: CRD42017077979). A literature search was performed in October 2017 using PubMed, Embase, the Cochrane Library, and other Chinese medical databases to identify studies. The meta-analysis was performed using Review Manager 5.3 software. Random-effect models were used to estimate mean differences (MDs) and 95% confidence intervals (CIs) of cytokine levels.

Results

Twelve studies were included in the meta-analysis, encompassing 2,422 children with MPP and 454 healthy control children. Serum TNF-α levels were significantly higher in children with MPP compared with healthy children (MD = 22.5, 95% CI = 13.78–31.22, P < 0.00001), and there was significant heterogeneity across studies (I² = 100%, P < 0.00001). Subgroup analyses showed no evidence for a difference in serum TNF-α levels between children with refractory and nonrefractory MPP. Serum IFN-γ levels did not significantly differ in children with MPP compared with healthy children (MD = 4.83, 95% CI = −3.27–12.93, P=0.24).

Conclusions

Our meta-analysis showed that serum TNF-α and IFN-γ levels were significantly elevated and unchanged, respectively, in pediatric MPP. Because infection by different pathogens has variable effects on serum TNF-α and IFN-γ levels, the finding could be helpful in developing novel diagnostic methods.

Reduced sB7-H3 Expression in the Peripheral Blood of Systemic Lupus Erythematosus Patients

Both membrane-bound and soluble forms of costimulatory molecules play important roles in immune-regulatory networks. B7-H3, a member of the B7 family, has been found with aberrant expression in tumors and infectious disease. However, the significance of sB7-H3 expression in systemic lupus erythematosus (SLE) has not been investigated. Using the peripheral blood of 78 SLE patients, we established a comprehensive database containing clinical data and relevant laboratory tests. We found that sB7-H3 expression in SLE patients was significantly lower compared with the healthy individuals. In addition, sB7-H3 levels in the patients were positively correlated with the disease activity as indicated by SLE disease activity index score, rashes, fever, and inflammatory cytokines. Moreover, sB7-H3 was associated with the counts of red blood cells and hemoglobin. Our findings suggest that sB7-H3 might counteract the aberrant immune response and potentially serve as a monitoring indicator of disease progression and therapeutic target in SLE treatment.

Screening and Identification of APOC1 as a Novel Potential Biomarker for Differentiate of Mycoplasma pneumoniae in Children

Background: Although Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia (CAP) in children, the currently used diagnostic methods are not optimal. Proteomics is increasingly being used to study the biomarkers of infectious diseases. Methods: Label-free quantitative proteomics and liquid chromatography-mass/mass spectrometry were used to analyze the fold change of protein expression in plasma of children with MP pneumonia (MPP), infectious disease control (IDC), and healthy control (HC) groups. Selected proteins that can distinguish MPP from HC and IDC were further validated by enzyme-linked immunosorbent assay (ELISA). Results: After multivariate analyses, 27 potential plasma biomarkers were identified to be expressed differently among child MPP, HC, and IDC groups. Among these proteins, SERPINA3, APOC1, ANXA6, KNTC1, and CFLAR were selected for ELISA verification. SERPINA3, APOC1, and CFLAR levels were significantly different among the three groups and the ratios were consistent with the trends of proteomics results. A comparison of MPP patients and HC showed APOC1 had the largest area under the curve (AUC) of 0.853, with 77.6% sensitivity and 81.1% specificity. When APOC1 levels were compared between MPP and IDC patients, it also showed a relatively high AUC of 0.882, with 77.6% sensitivity and 85.3% specificity. Conclusion: APOC1 is a potential biomarker for the rapid and noninvasive diagnosis of MPP in children. The present finding may offer new insights into the pathogenesis and biomarker selection of MPP in children.

Assessment of plasma B7-H3 levels in pediatric patients with different degrees of surgical stress

Background

Surgical stress initiates a series of host hormone, metabolism and immune responses, which predominantly affect the homeostatic mechanism of patients with major surgery. B7-H3 is a co-stimulatory molecule and has been shown to participate in both adaptive and innate immune responses. In this study we evaluated the clinical significance of plasma B7-H3 levels in pediatric patients with different types of operation and degrees of surgical stress.

Methods

A total of 48 children received pediatric general and cardiac surgery were recruited into this study. Based on the surgical stress scoring, children were divided into moderate stress (n = 14) and severe stress (n = 34) groups. Plasma B7-H3 levels were assessed at selected time points: before surgery, immediately after surgery, at day 1, day 3, and day 7 after surgery. Correlations between plasma B7-H3 levels and surgical stress scores were also examined.

Results

Plasma B7-H3 levels were significantly decreased in all 48 pediatric patients after surgery compared to the B7-H3 level before surgery (p < 0.01). Children with general surgery showed significant decreases in plasma B7-H3 immediately after surgery, and at day 3 and day 7 after surgery (p < 0.05, p < 0.01), whereas children with cardiac surgery showed reduced plasma B7-H3 immediately after surgery and at day 3 after surgery (p < 0.05). Plasma B7-H3 in cardiac surgery group was dropped much lower than that in general surgery group at day 1 (p < 0.05) and day 3 (p < 0.01) after surgery. Significantly reduced plasma B7-H3 was observed in the severe stress group, but not in the moderate stress group, immediately after surgery and at day 3 after surgery (p < 0.05), and severe stress group had significantly lower plasma B7-H3 levels than moderate stress group at day 1, day 3, and day 7 after surgery (p < 0.05). Furthermore, plasma B7-H3 levels at day 1 (p = 0.01) and day 3 (p = 0.025) after surgery correlated negatively with surgical stress scores.

Conclusions

Plasma B7-H3 levels were decreased significantly in children subjected to pediatric general and cardiac surgery, which is closely associated with the severity of surgical stress. The negative correlation of plasma B7-H3 levels at day 1 and day 3 after surgery with surgical stress scoring implicates that the plasma B7-H3 level might be a useful biomarker for monitoring stress intensity during pediatric surgery.

Increased concentrations of soluble B7-H3 and interleukin 36 in bronchoalveolar lavage fluid of Children with Mycoplasma pneumoniae pneumonia

Background

The purpose of this study is to explore the correlations of interleukin 36 (IL-36) and Soluble B7-H3 (sB7-H3) levels in bronchoalveolar lavage fluid (BALF) with clinical characteristics and laboratory findings.

Methods

A total of 35 children with M. pneumnoiae pneumonia (MPP) and 15 control subjects were enrolled. BALF concentrations of sB7-H3 and IL-36 were detected using enzyme-linked immunosorbent assays and clinical profiles of children with MPP were obtained.

Results

Children with MPP had significantly higher levels of sB7-H3 and IL-36 compared to control subjects (both P < 0.05). Meanwhile, children with pleural effusion had significantly higher levels of sB7-H3 and IL-36 compared to children without pleural effusion (both P < 0.05). BALF concentration of sB7-H3 was strongly associated with concentration of IL-36 (r = 0.796, P < 0.0001) and sB7-H3 was correlated with duration of fever (r = 0.427, P = 0.11) and length of stay (r = 0.345, P = 0.043). Both concentrations of sB7-H3 and IL-36 were significantly decreased in convalescent phase after treatment (both P < 0.05).

Conclusion

Both soluble B7-H3 and IL-36 may play an important role in pathogenesis of M. pneumoniae infection and sB7-H3 could be useful as a prognostic predictor or biomarker of MPP.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1555-6) contains supplementary material, which is available to authorized users.

Role of the Mycoplasma pneumoniae/Interleukin-8/Neutrophil Axis in the Pathogenesis of Pneumonia

Neutrophil infiltration is the characteristic pathological feature of M. pneumoniae pneumonia (MPP). This study aimed to explore the associations among neutrophil activity, clinical presentation, and role of the M. pneumoniae/interleukin-8 (IL-8)/neutrophil axis in the pathogenesis of MPP. A total of 42 patients with MPP were prospectively enrolled in the study. Neutrophil activity, including matrix metalloproteinase-9 (MMP-9), myeloperoxidase (MPO), and neutrophil elastase (NE), were measured. Clinical information was collected for all patients and control group. In vitro, IL-8 production was measured at different time points after M. pneumoniae infection of bronchial epithelial cells, and neutrophil activity was analyzed after IL-8 stimulation. The percentage of neutrophil in the bronchoalveolar lavage fluid was higher in the group of patients with high levels of M. pneumoniae DNA than in those with low levels of M. pneumoniae DNA (P < 0.05). IL-8, MMP-9, and NE in patients with MPP significantly increased compared with controls and decreased after treatment (P < 0.05). MPO and MMP-9 were associated with duration of fever (r = 0.332, P < 0.05) and length of stay (r = 0.342, P < 0.05), respectively. In vitro, M. pneumoniae induced IL-8 production by bronchial epithelial cells in a time dependent manner. MPO, MMP-9 and NE production by neutrophils significantly increased compared with medium controls after IL-8 stimulation. In summary, the M. pneumoniae/IL-8/neutrophil axis likely plays a vital role in the pathogenesis of MPP.

Decreased Interleukin-10 Responses in Children with Severe Mycoplasma pneumoniae Pneumonia

Several cytokines may play roles in the immunological pathogenesis of mycoplasmal pneumonia caused by Mycoplasma pneumoniae. In this study, we investigated serum cytokine profiles in children with mycoplasmal pneumonia. The serum levels of interleukin (IL)-8, IL-10, and IL-18 were examined using ELISA kits in 34 patients with M. pneumoniae infection (Group 1, 11 with severe mycoplasmal pneumonia; Group 2, 13 with mild mycoplasmal pneumonia; Group 3, 10 with asthma) and 32 age-matched, non-infected controls. The serum levels of IL-8, IL-10, and IL-18 increased significantly in patients with mycoplasmal pneumonia compared with those in controls (P<0.01). The serum levels of IL-10 decreased significantly in Group 1 compared with those in Group 2 (P<0.01). The serum levels of IL-18 increased significantly in Group 1 compared with those in Group 2 (P<0.01). The serum levels of IL-10 and IL-18 decreased significantly in 10 M. pneumoniae-infected patients with asthma compared with those in 24 M. pneumoniae-infected patients without asthma (P<0.01). We examined the level of interleukins (IL-8, IL-10 and IL-18) after the patients started therapy. The data showed that IL-18 were lower after therapy (P<0.01). Collectively, our data suggested that these cytokines may be involved in the pathogenesis of mycoplasmal pneumonia.

Detection of human bocavirus in nasopharyngeal aspirates versus in broncho-alveolar lavage fluids in children with lower respiratory tract infections

To compare the presence of human bocavirus (HBoV) in nasopharyngeal aspirates (NPA) versus broncho-alveolar lavage fluids (BAL) in children with lower respiratory tract infections (LRTIs), as revealed by real-time PCR, in order to confirm the diagnostic validity of NPA samples. A retrospective 5-year study was performed from 2009 to 2014 in 1,194 patients under the age of 17 years (mean age of 3 years) that were diagnosed with LRTIs and from whom both NPA and BAL were obtained. Clinical and demographic data were recorded, and NPA and BAL samples were analyzed for HBoV-positivity by real-time PCR. Of the 1,194 patients enrolled, 65 (5.4%) patients had HBoV detected from NPA, and 61 (5.1%) had HBoV detected from BAL. For HBoV, there was a significant association between the NPA and BAL samples (P < 0.001), but the diagnostic validity was relatively low (kappa = 0.414). When real-time PCR-positivity for HBoV in BAL was used as a reference for diagnosis, NPA had a good specificity and better positive predictive validity in male patients or those younger than 3 years of age. NPA has a similar yield and a good specificity for diagnosis of LRTIs with HBoV compared to BAL. The best diagnostic validity for NPA was detected in male patients or those younger than 3 years old.