The cellular immunophenotype expression of influenza A virus and influenza B virus infection in children.

Background: The innate immune response is the primary defense against influenza virus infection.
Methods: This is a prospective study carried out in children <18 years of age who were diagnosed with influenza A or influenza B infection. Demographic and clinical data, laboratory findings and cell immunophenotypes on first presentation were compared.
Results: With respect to immunophenotype, influenza A infection resulted in a higher fraction of CD14 ⁺ and CD4 ⁺ IL-17A ⁺ cells compared to children infected with influenza B. By contrast, influenza B infection resulted in a comparatively higher percentage of double-negative CD4 ^- CD8 ^- lymphocyte subsets. Influenza A infection was associated with comparatively higher percentages of CD4 ⁺ CD25 ^high Foxp3 ⁺ and CD4 ⁺ CD25 ^low Foxp3 ⁺ cells. By contrast, the percentage of CD8 ⁺ CD25 ^high and CD8 ⁺ CD25 ^low cells was similar among patients with influenza A infection and influenza B infection.
Conclusions: An improved understanding of the fraction of regulatory T cells with influenza virus infections may provide further understandings on immune responses.
Competing Interests: Declaration of Competing Interest No potential conflict of interest was reported by the author(s).
(Copyright © 2020 Elsevier Inc. All rights reserved.)