The Serum Value of NO and IL-17 were Increased in Children with Influenza A Viral Pneumonia.

BACKGROUND

Influenza A virus can cause severe respiratory infection in children and even result in immune system dysfunction. The aim of this study is to examine the clinical value of peripheral blood lymphocytes and serum nitric oxide (NO) and cytokines in children with influenza A viral pneumonia.

METHODS

Thirty children hospitalized with confirmed influenza A viral pneumonia and 30 healthy controls were enrolled in this study. The blood samples were collected from all the children and anti-coagulated with EDTA. The peripheral blood lymphocyte subsets were analyzed by flow cytometry. Griess assay were performed to calculate serum NO and nitrite (NO2-) levels. The serum concentrations of IFN-γ and IL-17 were measured by ELISA.

RESULTS

The serum levels of NO, NO2-, and IL-17 were significantly higher in children with influenza A viral pneumonia than controls (p < 0.01), while the level of IFN-γ had no significant difference (p = 0.515). Additionally, the patients had significantly lower percentages of peripheral blood CD3+, CD3+CD4+ T lymphocytes, and CD56+CD16+ natural killer (NK) cells than controls (p < 0.05), while CD3+CD8+ and CD4-CD8- (double negative, DN) T lymphocytes did not differ significantly (p > 0.05). Correlation analysis suggests that the serum NO level is positively correlated with IL-17 (p < 0.05).

Conclusions

The increased levels of NO and IL-17 may be related to dysregulated lymphocytes' immune response in children with influenza A viral pneumonia. These abnormalities may be the main cause of inflammatory lung damage, and thus have significant prognostic value.