Imbalanced anti-H1N1 immunoglobulin subclasses and dysregulated cytokines in hospitalized pregnant women with 2009 H1N1 influenza and pneumonia in Shenyang, China

Influenza virus can cause an acute respiratory illness of variable intensity. In our study, we describe the clinical and immunological characteristics of pregnant and nonpregnant women who were hospitalized with 2009 H1N1 influenza and pneumonia in Shenyang, China, from November 2009 to January 2010. Forty-two female patient infected with H1N1 were divided into groups according to pregnancy. Clinical data were collected. Cytokines and anti-H1N1 IgG subclasses were detected. We observed significant lymphopenia, hypoproteinemia, reduced CD4+T cell counts and CD4+/CD8+ ratios, reduced anti-H1N1 IgG subclasses IgG2 and IgG3 constituent ratios, elevated C reactive protein and interleukin-10 levels with regard to nonpregnant H1N1 group. Compared with the healthy pregnant group, the pregnant H1N1 group showed elevated aspartate aminotransferase and glutamic alanine aminotransferase levels, an increased interferon-gamma and interleukin-10 levels and reduced anti-H1N1 IgG subclasses IgG2, IgG3 and IgG4 combination ratios. There was a statistically significant association between imbalanced anti-H1N1 immunoglobulin subclasses and dysregulated cytokines in pregnant women with H1N1 infection.