Comparison of cytokine expression profiles in infants with a rhinovirus induced lower respiratory tract infection with or without wheezing: a comparison with respiratory syncytial virus.

Purpose: The aim of this study was to evaluate whether infants with rhinovirus (RV) infection-induced wheezing and those with respiratory syncytial virus (RSV) infection-induced wheezing have different cytokine profiles in the acute stage.

Methods: Of the infants with lower respiratory tract infection (LRTI) between September 2011 and May 2012, 88 were confirmed using reverse transcription polymerase chain reaction and hospitalized. Systemic interferon-gamma (IFN-γ), interleukin (IL)-2, IL-12, IL-4, IL-5, IL-13, and Treg-type cytokine (IL-10) responses were examined with multiplex assay using acute phase serum samples.

Results: Of the 88 patients, 38 had an RV infection (RV group) and 50 had an RSV infection (RSV group). In the RV group, the IFN-γ and IL-10 concentrations were higher in the patients with than in the patients without wheezing (=0.022 and =0.007, respectively). In the RSV group, the differences in IFN-γ and IL-10 concentrations did not reach statistical significance between the patients with and the patients without wheezing (=0.105 and =0.965, respectively). The IFN-γ and IL-10 concentrations were not significantly different between the RV group with wheezing and the RSV group with wheezing (=0.155 and =0.801, respectively), in contrast to the significant difference between the RV group without wheezing and the RSV group without wheezing (=0.019 and =0.035, respectively).

Conclusion: In comparison with RSV-induced LRTI, RV-induced LRTI combined with wheezing showed similar IFN-γ and IL-10 levels, which may have an important regulatory function.