hapten

Full Definition

A low-molecular-weight substance that cannot independently trigger an immune response but becomes antigenic when conjugated to a carrier protein. In pediatric immunology, haptens are particularly important in understanding drug allergies, where medications act as haptens by binding to endogenous proteins to form immunogenic complexes. Common pediatric examples include penicillin allergies and contact sensitization to metals in jewelry or medical devices.

Usage

Usage note: Always singular form; plural is 'haptens', not 'haptenes'.

In Context

• "Penicillin acts as a hapten, requiring conjugation with host proteins to elicit an allergic response." — immunology textbook
• "The nickel hapten-protein complex was identified as the cause of the patient's contact dermatitis." — allergy consultation note