Oral Peanut Immunotherapy

Our hypothesis is that chronic antigen exposure during peanut oral immunotherapy (OIT) will
induce beneficial changes in the specific immune response, including: 1) anergy of IgE
effector immune cells (e.g., mast cells, basophils) resulting in clinical desensitization; 2)
induction of de novo, long lived (memory) B cell responses that antagonize specific IgE and
confer immune tolerance. The investigators will test this hypothesis in the following
specific aims:

1. Induce desensitization in peanut allergic subjects with peanut OIT and evaluate the
safety of the peanut OIT desensitization protocol.

2. Induce long-standing tolerance in peanut allergic subjects with maintenance peanut OIT
and evaluate the efficacy of allergen-specific testing to predict tolerance.

3. Longitudinally evaluate basophil and mast cell reactivity in subjects receiving peanut
OIT and their relationship to the induction of desensitization.

4. Longitudinally evaluate the allergen-specific B-cell repertoire in subjects receiving
peanut OIT and its relationship to the induction of tolerance.

Inclusion criteria:

1. Diagnosis of peanut allergy by a positive prick skin test to peanut (> 8 mm reaction
wheal) or CAP FEIA >10 and a history of objective clinical symptoms within one hour
after ingestion of peanuts

2. Ability to provide informed consent.

3. Males and females of all ethnic/racial groups between 7 and 21 years who are otherwise
healthy.

Exclusion criteria:

1. Clinical history of a severe anaphylactic reaction known or suspected to be caused by
ingestion of peanut that required treatment with 2 or more administrations of
epinephrine or hospitalization

2. Moderate to Severe Asthma as defined using the Impairment or Risk Criteria of the
current NHBLI Guidelines for the Diagnosis and Management of Asthma
(http://www.nhlbi.nih.gov/guidelines/asthma/)

3. Poorly controlled Asthma as defined using the Control Criteria of the current NHBLI
Guidelines for the Diagnosis and Management of Asthma
(http://www.nhlbi.nih.gov/guidelines/asthma/)

4. Diagnosis of other severe or complicating medical problems

5. Autoimmune or chronic immune or gastrointestinal inflammatory conditions, including
Celiac Disease, Inflammatory Bowel Disease and Eosinophilic Gastrointestinal Disorders

6. Primary Immune Deficiency

7. Use of beta blockers, angiotension converting enzyme inhibitors, or monoamine oxidase
inhibitors

8. Women of childbearing potential who are pregnant, planning to become pregnant, or
breastfeeding

9. Use within the past year of other systemic immunomodulatory treatment, including
allergen immunotherapy, use of biologics with an immune target, including Xolair