Atopic dermatitis (AD) is a chronic skin disorder characterized by recurrent viral skin infections. A small subset of patients with AD suffer from disseminated viral infections, e.g., eczema herpeticum (ADEH+), after herpes simplex infection (HSV) or eczema vaccinatum (EV) after smallpox vaccination. Interferon gamma (IFNγ) plays a critical role in the innate and acquired immune responses by activating macrophages, enhancing natural killer cell activation, and promoting T cell differentiation, as well as regulating B cell isotype switching to immunoglobulin (Ig) G2a. Recent studies have demonstrated that IFNγ generation was significantly decreased after stimulation with HSV ex vivo. The purpose of this study is to determine if deficient IFNγ induction leads to susceptibility to HSV infection in ADEH+ patients.
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+.
Study Type
OBSERVATIONAL
Enrollment
84
National Jewish Health
Denver, Colorado, United States
Expression of IFNγ and Interleukin-12 (IL-12), in response to stimulation with Herpes Simplex Virus 1 (HSV-1), Vaccinia Virus (VV), and Pattern Recognition Receptors (PRR) agonists
Protein and messenger ribonucleic acid (mRNA) levels of IFNγ, and the IFN-γ promoting cytokine, IL-12, produced by Cluster of Differentiation 14 (CD14+) monocytes in response to stimulation with HSV-1, VV, and various PRR agonists
Time frame: Day 1
Cell surface expression of Major Histocompatibility complex (MHC) class I and class II and co-stimulatory molecules on CD14+ cells in response to IFNγ and Interferon-alpha (IFNα) stimulation
Time frame: Day 1
Production of IL-18 and IFNα protein and mRNA by CD14+ cells following stimulation with HSV-1, VV, or PRR agonists
Time frame: Day 1
Production of IFNγ protein by Cluster of Differentiation 8 (CD8+) T cells in response to stimulation with recombinant human cytokines including but not limited to IL-12, IL-18, and IFNα
Time frame: Day 1
Protein expression of IFNγ receptor and IFNα/β receptor on CD14+ cells
Time frame: Day 1
Immunodominant HSV-1 peptide repertoires
Analysis of immunodominant HSV-1 peptide repertoires with related Human Leukocyte Antigen (HLA) in ADEH+, ADEH-, and non-atopic participants
Time frame: Day 1
High-throughput gene expression profiling to analyze ribonucleic acid (RNA) from HSV-1 stimulated and sham stimulated CD14+ monocytes
Global transcriptional response of CD14+ monocytes to stimulation with HSV-1 as evaluated by GeneChip Profiling
Time frame: Day 1
Production of protein and RNA of IFN family members and any related pro- or anti-inflammatory cytokines/chemokines in response to stimulation of PBMCs or purified monocytes
IFN family members include IFNα, Interferon beta (IFNβ), and IFNγ. Related pro- or anti-inflammatory cytokines/chemokines include, but are not limited to IL-29 and IL-10
Time frame: Day 1
Expression of MHC and co-stimulatory molecules on CD14+ cells in response to stimulation with HSV-1, VV, or PRR agonists
Time frame: Day 1
Viral titer of VV as determined by plaque assay following incubation of virus with PBMCs
Time frame: Day 1
Gene expression profiles and gene variant profiles of PBMCs stimulated with HSV-1 as assayed by RNA-seq
Time frame: Day 1
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