Altered chromatin landscape in circulating T follicular helper and regulatory cells following grass pollen subcutaneous and sublingual immunotherapy.

Background: Allergen-specific immunotherapy is a disease-modifying treatment that induces long-term T-cell tolerance.

Objective: We sought to evaluate the role of circulating CXCR5PD-1 T follicular helper (cT) and T follicular regulatory (T) cells following grass pollen subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) and the accompanying changes in their chromatin landscape.

Methods: Phenotype and function of cT cells were initially evaluated in the grass pollen-allergic (GPA) group (n = 28) and nonatopic healthy controls (NAC, n = 13) by mathematical algorithms developed to manage high-dimensional data and cell culture, respectively.