Reduction of Peanut Reactivity and Immune Modulation With Anti-IgE Therapy

The study aims to characterize the pathways involved in the allergic response, primarily in food allergy; specifically peanut allergy. We will also study non-allergic donors as well as patients with atopic disorders, primarily as control subjects. All eligible study participants will have documented elevated total IgE levels, peanut positivity or another antigen/allergen specific elevated IgE (ie common indoor/outdoor allergens) prior to being enrolled in the study. Our study will focus on allergic as well as non-allergic individuals. We plan on collecting samples from a total of 60 patients during one time point (peanut allergic individuals, non-atopic/allergic individuals, atopic individuals-other than peanut allergy). We believe that such a pilot study represents the ideal approach to identify effective therapeutic interventions and to simultaneously better understand the underlying mechanistic properties involved in the allergy cascade. We plan to obtain a detailed history prior to enrollment as well as objective data (ie SPT as well as Immunocap testing results). There will be 3 study groups and studies will be performed on approximately 20 peanut allergic patients, 20 non-allergic controls, and 20 allergic/atopic (non-peanut allergic, but allergic to indoor/outdoor allergen) individuals. There will be one blood draw required at each visit (weeks 0, 4, 8). Each blood draw will require 105 ml of whole blood to be collected in ten heparinized 10-mL tubes and one EDTA tube. We plan to assess the levels of total IgE and IgG as well as antigen specific IgG and IgE in the peripheral blood of patients. We will specifically perform ELISA testing that detects these levels. We will also perform in vitro CD4+ T cell proliferation assays. For this purpose, patients' peripheral T cells will be isolated with a combination of magnetic beads and flow cytometric sorting.

Inclusion criteria

for Groups 1-3:

Group 1: Peanut allergic individuals (n=20)

• 18-65 years of age
• Positive ImmunoCAP test (Optional)
• Documented elevated total IgE levels, peanut positivity or another antigen/allergen specific elevated IgE (ie common indoor/outdoor allergens)
• Experienced at least one of the following symptoms within 60 minutes of exposure:

• Skin-related symptom (i.e., hives and edema)
• Respiratory-related symptom (i.e., wheezing, throat tightness, repetitive coughing, and dyspnea)
• Gastrointestinal-related symptom (i.e., vomiting and diarrhea)

Group 2: Allergic/atopic individuals (not allergic to peanut; n=20)

• 18-65 years of age.
• Positive ImmunoCAP test (Optional)
• Documented elevated total IgE levels or an indoor/outdoor antigen/allergen (other than peanut) specific elevated IgE (ie common indoor/outdoor allergens).
• Experienced at least one of the following symptoms within 60 minutes of exposure:

• Skin-related symptom (i.e., hives and edema).
• Respiratory-related symptom (i.e., wheezing, throat tightness, repetitive coughing, and dyspnea).
• Gastrointestinal-related symptom (i.e., vomiting and diarrhea)

Group 3: Non-allergic individuals (healthy controls; n=20)

• 18-65 years of age.
• Negative ImmunoCAP test (Optional)
• Documented absence or low total IgE levels, or negativity for an antigen/allergen specific elevated IgE (ie common indoor/outdoor allergens).
• Has not experienced at least one of the following symptoms within 60 minutes of exposure to a particular substance:

• Skin-related symptom (i.e., hives and edema).
• Respiratory-related symptom (i.e., wheezing, throat tightness, repetitive coughing, and dyspnea).
• Gastrointestinal-related symptom (i.e., vomiting and diarrhea)

Exclusion criteria

for Groups 1-3:

• Prior therapy with anti-IgE
• Steroid use greater than 10 mg/d prednisone or equivalent 30 days prior to enrollment
• Any immunosuppressive drug use within 3 months prior to screening (mycophenolate mofetil, hydroxychloroquine, azathioprine, methotrexate, leflunomide, rituximab, cyclophosphamide, intravenous immunoglobulin, plasmapheresis)
• Ongoing chronic infection (viral, bacterial or fungal) including known HIV, Hepatitis B/C
• Acute infection receiving any antibiotics within 30 days prior to screening
• Probiotics (greater than estimated 109 cfu or organisms per day) within 30 days prior to enrollment (with the exception of fermented beverages, milks or yogurts).
• Malignancy within one year prior to screening (with the exception of non-metastatic squamous or basal cell skin carcinomas and cervical carcinoma if received curative surgical treatment)
• Known illicit drug or alcohol abuse
• Pregnancy