Shift from Th2 to Th1 response in immunotherapy with venoms.

Area of Science:

• Immunology
• Allergy Research
• T-cell immunology

Background:

• T lymphocytes regulate immune responses, including antibody production and mast cell activity.
• Immune tolerance in allergen-specific immunotherapy (SIT) may involve altered T-helper 2 (Th2) and T-helper 1 (Th1) responses.

Purpose of the Study:

• To compare T lymphocyte function in Hymenoptera venom allergy patients versus healthy controls.
• To monitor T lymphocyte function during SIT in allergy patients.

Main Methods:

• Peripheral blood mononuclear cells (PBMCs) from 11 patients and 7 controls were stimulated with allergen (Ag) and mitogens.
• Cytokine release (IL-2, IFN-γ, IL-4, IL-5) was measured.
• T lymphocyte function was assessed before, during, and after rush SIT.

Main Results:

• Allergy patients initially showed a Th2-dominant response (higher IL-4, lower IFN-γ) to Ag stimulation compared to controls' Th1 response.
• Rush SIT significantly increased spontaneous IFN-γ release in patients.
• After 6 months of SIT, patient PBMC responses normalized, resembling those of healthy controls.

Conclusions:

• SIT effectively modulates T lymphocyte responses in Hymenoptera venom allergy, shifting from Th2 towards a Th1 profile.
• This cytokine profile normalization during SIT contributes to the development of immune tolerance.
• Understanding these T-cell dynamics is crucial for optimizing allergy immunotherapy strategies.