Biological standardization of pollen allergens from India

Area of Science:

• Allergen standardization
• Immunology
• Pollen allergy research

Background:

• Allergen standardization is crucial for effective immunotherapy.
• Western allergens are standardized by biological potency, but Indian allergens lack this.
• Pollen allergies are prevalent in India, necessitating standardized extracts.

Purpose of the Study:

• To standardize two key Indian pollen allergens, Ricinus communis and Holoptelea integrifolia, using biological methods.
• To establish biological units for these pollen extracts, enabling accurate dosing for immunotherapy.
• To address the lack of standardized Indian pollen allergens in clinical practice.

Main Methods:

• Followed established protocols (Dreborg and Grimmer, 1983) for allergen standardization.
• Conducted skin prick tests on 15 allergic patients using serial dilutions of Ricinus communis and Holoptelea integrifolia pollen extracts.
• Utilized 50% glycerinated buffer and histamine dihydrochloride as negative and positive controls, respectively.

Main Results:

• Skin test wheal size decreased systematically with increasing allergen dilution.
• Mean relative wheal diameters (% of histamine reaction) indicated dose-dependent responses for both allergens.
• Determined histamine equivalent concentrations: 1:17 for Ricinus communis and 1:22 for Holoptelea integrifolia per 1,000 Biological Units (BU).

Conclusions:

• Successfully standardized Ricinus communis and Holoptelea integrifolia pollen extracts using biological methods.
• The established Biological Units (BU) provide a basis for quantitative allergen immunotherapy with Indian pollens.
• This standardization is a critical step towards improving the diagnosis and treatment of pollen allergies in India.