Q:

8/20/2013
I have a patient who works as a director of a zoo that specializes in big cats, African antelope, and giraffes. She also has clinical allergic reactions to these animals that she must physically interact with on a daily basis. As such, it is limiting her efficacy at work. We are currently exploring antihistamine use for her which may be sufficient.

However, she is interested in an immunotherapy option as well. I would expect that cat immunotherapy could be helpful for the big cats, but I am unaware of any other animal extracts that may be effective/cross reactive for antelope or giraffe in the literature. I don't believe such allergens have been extracted or identified from these animals. Are you aware of any research in this area? Thank you for your time.

A:

Thank you for your inquiry.

As you can see from the abstract copied below, cross-reactivity has been demonstrated between allergens found in domestic cats and “big cats.” Thus there is at least some rational in trying immunotherapy.

J Allergy Clin Immunol. 1990 Jul;86(1):107-16.
Evidence for a Fel d I-like molecule in the "big cats" (Felidae species).
de Groot H, van Swieten P, Aalberse RC.
Source
Central Laboratory, The Netherlands Red Cross Blood Transfusion Service, Amsterdam.
Abstract
In this study, we investigated the cross-reactivity pattern of IgE and IgG4 antibodies to the major feline allergen, Fel d I. We studied the IgE and IgG4 response of 11 cat-allergic patients against Fel d I-like structures in eight members of the Felidae family: ocelot, puma, serval, siberian tiger, lion, jaguar, snow leopard, and caracal. Hair from these "big cats" was collected, extracted, and used in a RAST system and histamine-release test. By means of a RAST-inhibition assay with affinity-purified Fel d I from cat dander, it was established that, in the Felidae species, a Fel d I equivalent is present that reacts with IgE and IgG4 antibodies. We found that all patients had cross-reacting IgE antibodies to seven of the Felidae tested; no IgE antibodies reactive with the caracal were found. Eight of 10 patients with IgG4 antibodies directed to cat dander also had IgG4 antibodies directed to several Felidae species, including the caracal. However, the correlation between the IgE and the IgG4 antibody specificity was low, indicating that, in the case of Fel d I IgE and IgG4, antibodies do not necessarily have the same specificity.

Thank you again for your inquiry and we hope this response is helpful to you.

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology