IL-21 expression during sublingual immunotherapy for allergic rhinitis

Area of Science:

• Immunology
• Allergology
• Biochemistry

Background:

• Allergic rhinitis (AR) involves immunoglobulin E (IgE)-mediated inflammation.
• Interleukin-21 (IL-21) influences immune cells and IgE production.
• Understanding IL-21's role in AR is crucial for treatment.

Purpose of the Study:

• To investigate Interleukin-21 (IL-21) expression changes after sublingual immunotherapy (SLIT) in allergic rhinitis (AR) patients.
• To assess the correlation between IL-21, immunoglobulin E (IgE), and Th2 cytokines.
• To evaluate IL-21 as a potential biomarker for SLIT efficacy.

Main Methods:

• Fifty AR patients received standardized house dust mite (HDM) allergen extract via SLIT.
• Serum IL-21, Th2 cytokines, and IgE levels were quantified using ELISA.
• Statistical analyses compared pre- and post-treatment levels and assessed correlations.

Main Results:

• SLIT significantly decreased serum IL-21, Th2 cytokines, and IgE levels after 3 years.
• Effective SLIT responders showed greater reductions compared to non-responders.
• IL-21 levels correlated positively with IL-4 and IgE.

Conclusions:

• Sublingual immunotherapy (SLIT) downregulates IL-21 and Th2 cytokine expression in AR.
• IL-21 shows potential as a predictive biomarker for SLIT effectiveness in AR patients.
• This study highlights IL-21's involvement in the immunomodulatory effects of SLIT.