Symptomatic dermographism (factitious urticaria)--passive transfer experiments from human to monkey

Area of Science:

• Dermatology
• Immunology
• Allergy

Background:

• Dermographism, or skin writing, is a condition where stroking the skin causes urticarial wheals.
• The underlying mechanisms of passive transfer in dermographism are not fully understood.

Purpose of the Study:

• To investigate the feasibility of passive transfer of dermographism from human patients to non-human primates.
• To explore potential animal models for studying dermographism.

Main Methods:

• Passive transfer experiments were conducted on three monkey species: Macaca mulatta, Macaca nemestrina, and Macaca fascicularis.
• Human serum from patients with various urticaria types (severe symptomatic dermographism, cholinergic urticaria, chronic idiopathic urticaria) and normal subjects was intradermally injected.
• Dermographism was assessed 24 hours post-injection using a calibrated dermographometer and Evans blue dye.

Main Results:

• Positive dermographism responses were observed in Macaca nemestrina after injection with serum from severe symptomatic dermographism patients.
• One positive response was successfully reproduced in Macaca fascicularis one month later.
• A faint response was noted with serum from a normal subject, suggesting minimal non-specific reactivity.

Conclusions:

• These findings demonstrate the possibility of passive transfer of dermographism from humans to monkeys.
• This study establishes a potential non-human primate model for further research into the pathogenesis of dermographism.