Interferon Responses in Eczema Herpeticum

The investigators hypothesize that defective IFNγ responses in peripheral blood mononuclear
cells (PBMCs) from ADEH+ patients results from aberrant pattern recognition receptors (PRR)
signaling in antigen-presenting cells (APCs) resulting in low level production of IL-12, an
essential cytokine for IFNγ generation. This study will compare results from 40 ADEH+, 40
ADEH-, and 40 non-atopic participants.

Study procedures will typically be completed in one visit; however, participants may be
asked to return for additional unscheduled visit(s) occurring as frequently as every 3
months for the duration of the study to provide an additional blood sample for further
characterization of immune mechanisms leading to reduced IFNγ responses in ADEH+.

Participant Inclusion Criteria:

Participants who meet all of the following criteria are eligible for enrollment:

- have a history of AD with or without a history of Eczema Herpeticum (EH) as diagnosed
using the Atopic Dermatitis Research Network (ADRN) Standard Diagnostic Criteria OR

--are non-atopic as diagnosed using the ADRN Standard Diagnostic Criteria

- are willing to sign the informed consent form or whose parent or legal guardian is
willing to sign the informed consent form (age appropriate) prior to initiation of
any study procedure

- are willing to sign the assent form, if age appropriate.

Participant Exclusion Criteria:

Participants who meet any of the following criteria are not eligible for enrollment:

- have a history of any systemic illness (e.g., immunodeficiency disorders such as
human immunodeficiency virus [HIV] or lupus erythematosus) other than the condition
being studied

- have an active systemic malignancy, excluding uncomplicated non-melanoma skin cancer

- have any skin disease other than AD that might compromise the stratum corneum barrier
(e.g., bullous disease, psoriasis, cutaneous T cell lymphoma [also called Mycosis
Fungoides or Sezary syndrome], dermatitis herpetiformis, Hailey-Hailey, or Darier's
disease)

- have a first degree relative already enrolled in the study

- are determined not to be eligible in the opinion of the Investigator.

Participants who meet any of the following criteria are not eligible for enrollment but
may be reassessed:

- have active eczema herpeticum at the Enrollment Visit

- have taken systemic immunosuppressive drugs including cyclosporine or oral steroids
within 30 days of the Enrollment Visit

- have a fever >/= 38.5 ºC (101.3 ºF) at the Enrollment Visit.