Changes in lymphocyte subsets and serum IFN-γ levels in children with toxoplasma infection

Abstract:

Objective To study the changes and significance of lymphocyte sunsets and serum interferon-γ (IFN-γ) levels in children with toxoplasma infection. Methods Thirty-four children who were newly diagnosed with toxoplasma infection (TOX-IgM⁺ group) between January 2011 and April 2014, 12 children who had ever been diagnosed with toxoplasma infection (TOX-IgG⁺ group), and 54 healthy children (control group) were enrolled. The percentages of CD4⁺, CD8⁺, CD19⁺ and NK cells in peripheral blood lymphocytes were detected by flow cytometry. Serum levels of IFN-γ were measured using ELISA. Results The percentages of CD4⁺ cells and the CD4⁺/CD8⁺ ratio in the TOX-IgM⁺ group were significantly lower than in the TOX-IgG⁺ and control groups, while the percentages of CD8⁺ and NK cells and serum IFN-γ levels were significantly higher than in the other two groups (P<0.05). The TOXIgG⁺ group had higher serum IFN-γ levels than the control group (P<0.05). There was a positive correlation between the percentage of CD8⁺ cells and serum IFN-γ levels in the TOX-IgM⁺ group (r=0.756; P<0.05). Conclusions CD4⁺, CD8⁺ and NK cells may play important roles in the resistance against toxoplasma infection by promoting the secretion of cytokines.