Intervention with Polyvalent Bacterial Lysate Modulates T Helper Cell Subsets in Polish Children with Grass...

Area of Science:

• Immunology
• Allergology
• Pediatrics

Background:

• Allergic rhinitis (AR) significantly impacts children's quality of life.
• Bacterial lysates (BLs) show promise in AR treatment, but their immunomodulatory effects require further elucidation.
• Understanding the immune system's response to BLs is crucial for optimizing AR management.

Purpose of the Study:

• To assess the immunomodulatory effects of sublingually administered polyvalent mechanical BL (PMBL) in children with grass pollen-induced AR.
• To evaluate changes in T helper (Th) cell-associated transcription factors and cytokines following PMBL treatment.
• To investigate the impact of PMBL on Th1, Th2, Th10, Th17, and Treg-like immune responses.

Main Methods:

• A randomized, double-blind, placebo-controlled trial (NCT04802616) was utilized.
• Children aged 5-17 with grass pollen-AR received either sublingual PMBL or placebo over three cycles.
• Peripheral blood mononuclear cells were analyzed via flow cytometry before and after the pollen season to assess immune marker expression.

Main Results:

• The PMBL group showed increased T-bet, E4BP4, FoxP3, IFN-γ, and IL-10, with decreased GATA3 and IL-4.
• The placebo group exhibited increased GATA3, RORγT, and IL-4, with decreased T-bet.
• Compared to placebo, the PMBL group demonstrated higher Th1, Th10, and Treg markers, and lower Th2 and Th17 markers.

Conclusions:

• Sublingual PMBL effectively modulates Th cell transcription factors and cytokines in pediatric grass pollen-AR.
• PMBL treatment promotes Th1, Th10, and Treg-like immune responses.
• The findings suggest a reduction in Th2-associated allergic activity with PMBL administration.