Methods: Peripheral blood mononuclear cells (PBMCs) from healthy (n=10) and current asthmatic
children (n=10) (based on Global Initiative for Asthma guidelines) were stained with 30 metal-conjugated antibodies for surface and intracellular targets. Plasma total IgE levels were measured. Pyrosequencing of the FoxP3 gene at 10 different CpG sites was also performed.
Results: T cell subsets (Tr1, Treg, Th1, Th2, Th17, TCRgd) were identified using both Flow-Jo and 2
dimensional display using viSNE. Methylation at 4 CpG sites in the promoter region was negatively correlated with the percentage of Tr1 cells (CpG -146, p<.01; CpG-133, p<.01; CpG -127, p<.03; CpG -83, p<.02). IgE level negatively correlated with percentage of Treg cells (p<.05). In addition, there was a trend for asthmatics to have fewer Tr1 cells than healthy controls (p<.08).
Conclusions: This study is the first to our knowledge to identify of all of these T cell subsets using mass cytometry. Analysis at a single-cell level