Blood Samples for the Study of Peanut, Tree Nut and Other Food Allergies

Inclusion Criteria:

This protocol is to draw blood for a variety of related studies of food allergy. For this reason, we will list each group of subjects and the inclusion criteria for that group.

1. De-identified sera or plasma from patients who have undergone Oral ImmunoTherapy (OIT) for peanut allergy. These samples already exist.

   * Inclusion criteria:

     1. patients have been enrolled in a controlled trial of OIT for peanuts, and had at least one oral challenge.
     2. Age 1-75.
2. De-identified samples from patients who are undergoing clinically indicated food challenges for peanut allergy.

   * Inclusion criteria:

     1. concern regarding possible allergy to peanuts,
     2. age 1-75,
     3. plan to undergo a clinically indicated challenge with peanuts.
3. Patients with peanut allergy.

   * Inclusion criteria:

     1. excellent history of a systemic reaction to peanuts,
     2. age 6-75.
4. Patients with other food allergies (especially tree nuts).

   * Inclusion criteria:

     1. excellent history of a systemic reaction to tree nuts or other foods,
     2. age 6-75.
5. Normal controls.

   * Inclusion criteria:

     1. no known food allergies,
     2. recent ingestion of peanuts without difficulty, and
     3. age 6-75.

Exclusion Criteria:

1. Any known significant medical or psychiatric diagnosis
2. Use of an investigational drug within 30 days
3. Use of omalizumab (anti-IgE; Xolair) within 6 months