Initial immunological changes as predictors for house dust mite immunotherapy response.

Area of Science:

• Immunology
• Allergy Research
• Immunotherapy Mechanisms

Background:

• Specific immunotherapy (SI) is the sole etiological treatment for allergies, but its mechanisms remain unclear.
• SI is known to modulate T-helper (Th) cell subsets, shifting from Th2 towards Th1/Treg phenotypes.
• The immunological differences underlying patient responses to SI require further investigation.

Purpose of the Study:

• To investigate immunological changes during a 1-year course of Dermatophagoides pteronyssinus (DP) SI.
• To correlate these immunological shifts with clinical outcomes in patients undergoing SI.
• To identify distinct immunological patterns differentiating responders from non-responders.

Main Methods:

• 34 patients with DP allergy received 1 year of subcutaneous immunotherapy (SCIT).
• Patients were categorized as responders or non-responders based on symptom improvement.
• Peripheral blood analysis included flow cytometry for cell phenotypes and cytokine production, mRNA quantification for transcription factors, and serum immunoglobulin measurements.

Main Results:

• 82% of patients demonstrated symptom improvement after 1 year of SCIT.
• Responders exhibited increased serum IgG4 (sIgG4) levels, but no change in Basophil Activation Test (BAT) reactivity.
• Immunological shifts in responders included increased T-BET/FOXP3, nDer p 1-specific Th1/Treg frequencies, and decreased Th2, Th9, and Th17 cells, correlating with cytokine level changes.

Conclusions:

• Significant immunological differences exist between responders and non-responders to DP-SCIT.
• Responders initially presented with lower Th1 and higher Th2, Th9, and Th17 cell frequencies.
• One year of DP-SCIT induced increased sIgG4 production and a shift from Th2 towards Th1/Treg responses in responders.