Effects of recombinant fusion protein interleukin-18 on expression of immune-inflammatory factors in mice infected with Staphylococcus aureus / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To observe the effects of recombinant fusion protein interleukin (IL)-18 on the expression of immune-inflammatory factors in the mice infected with Staphylococcus aureus (SA), and to investigate the mechanism of action of IL-18 in defense of SA infection in vivo.</p><p><b>METHODS</b>A total of 40 specific pathogen-free female BLAB/c mice were randomly divided into four groups: control, SA infection, immunized, and intervention. A mouse model of SA infection was established by nasal inoculation with SA liquid. The immunized group and the intervention group were intranasally given IL-18 before SA modeling, and then the SA infection group and the intervention group received the nasal inoculation with SA liquid; the control group was treated with phosphate buffered saline instead. The levels of IL-4, interferon (IFN)-γ, tumor necrosis factor (TNF), granulocyte colony-stimulating factor (G-CSF), IgM in the serum and bronchoalveolar lavage fluid (BALF) of mice were measured by enzyme-linked immunosorbent assay. The expression of macrophage inflammatory protein (MIP)-1α mRNA and MIP-2β mRNA in the lung tissue of mice were determined by real-time fluorescent quantitative PCR.</p><p><b>RESULTS</b>Compared with the control group, the SA infection group and the immunized group had significantly higher levels of IL-4, G-CSF, and IgM in the serum and BALF and expression of MIP-1α mRNA and MIP-2β mRNA in the lung tissue (P<0.05); the SA infection group had a significantly lower level of IFN-γ and a significantly higher level of TNF in the serum and BALF (P<0.05); the immunized group had a significantly higher level of IFN-γ in the serum and BALF (P<0.05). Compared with the SA infection group, the intervention group had significantly higher levels of IL-4, IFN-γ, G-CSF, and IgM in the serum and BALF and expression of MIP-1α mRNA in the lung tissue. In contrast, the intervention group showed a significantly lower level of TNF in the serum and BALF and expression of MIP-2β mRNA in the lung tissue (P<0.05). All the above indicators in the intervention group were significantly higher than those in the control group (P<0.05), except the serum level of IFN-γ.</p><p><b>CONCLUSIONS</b>In the mice infected with SA, the recombinant fusion protein IL-18 by mucosal immunity can affect inflammatory factors in the serum and BALF and the expression of MIP-1α mRNA and MIP-2β mRNA in the lung tissue to promote the anti-infective immune response and enhance the ability to clear pathogens.</p>

Clinical analysis of immune function changes in children with bronchial pneumonia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate changes in serum complement, immunoglobulins and lymphocyte subsets in children with common and severe bronchial pneumonia, and the role of immune function testing in bronchial pneumonia.</p><p><b>METHODS</b>Twenty children with common bronchial pneumonia, 20 with severe bronchial pneumonia and 20 healthy children (as controls) were enrolled in this study. Immunization rate scattering turbidimetry and six-color flow cytometry were used to detect changes in serum levels of IgA, IgG and IgM, complement C3 and C4 and CD3(+), CD4(+), CD8(+), CD16(+), CD56(+) and CD19(+) cells.</p><p><b>RESULTS</b>The IgA levels of children with common and severe pneumonia were significantly lower than in the control group (P<0.05). The IgG level of children with severe pneumonia was significantly lower than in the control group (P<0.05). There were no significant differences in the levels of IgM and complement C3 and C4 between the two pneumonia groups and the control group (P>0.05). Compared with the controls, the children with severe pneumonia showed significantly lower CD4(+) and CD3(+) counts (P<0.05) and a significantly higher CD19(+) count (P<0.05), and the CD16(+) and CD56(+) counts of children with severe pneumonia were significantly lower than in the controls and in children with common pneumonia (P<0.05). There were no differences in CD8(+) count and CD4(+)/CD8(+) ratio between the two pneumonia groups and the control group (P>0.05).</p><p><b>CONCLUSIONS</b>Immune dysfunction exists in children with bronchial pneumonia, especially those with severe pneumonia. Changes in immune function are correlated with the severity of pneumonia. Immune function testing in children with pneumonia has important clinical significance.</p>

Urinary leukotrience E(4) level in children with asthma / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Cysteinyl leukotriene (CysLTs) plays an important role in airway inflammation and remodeling in asthma. Measurement of urinary leukotriene E(4) (LTE(4)) is a sensitive and noninvasive method of assaying total body CysLTs level. This study aimed to evaluate the clinical significance of urinary leukotriene E(4) (LTE(4)) in childhood asthma.</p><p><b>METHODS</b>Sixty children with acute asthma were randomly divided into montelukast (leukotriene receptor antagonist) treatment and conventional treatment groups (n = 30 each). Urinary LTE(4) levels were measured using ELISA and the airway resistance Rint was assessed by the lung function instrument at the acute and the convalescence phases. Twenty healthy children were used as the control group.</p><p><b>RESULTS</b>Urinary LTE(4) levels in asthmatic children at the acute and the convalescence phases were significantly higher than those in the control group (p<0.01). The urinary LTE(4) levels at the convalescence phase were significantly reduced compared with those at the acute phase in asthmatic children (p<0.01). More significantly decreased urinary LTE(4) levels were noted in the montelukast treatment group than the conventional treatment group at the convalescence phase (p<0.01). In the acute phase, there was no correlation between urinary LTE4 level and Rint in asthmatic children.</p><p><b>CONCLUSIONS</b>Urinary LTE(4) level is significantly increased in children with acute asthma. Urinary LTE(4) is a useful marker for the diagnosis of asthma and can be as a predictor of asthma control and marker of susceptibility to treatment with leukotriene receptor antagonists.</p>