Human Immunity Against Staphylococcus Aureus Skin Infection

The incidence of community-associated (CA) staphylococcal infections, especially those caused
by methicillin-resistant Staphylococcus aureus (MRSA), has increased dramatically in recent
years. Skin and soft tissues are the primary site for most of these infections, and skin or
mucosal colonization increases the risk of disseminated disease. Many patients without
apparent underlying immune dysfunction suffer from recurrent and persistent skin infections
with MRSA. Additionally, patients with conditions such as atopic dermatitis and Hyper IgE (or
Job s) Syndrome (HIES) are disproportionately affected. Although underlying host molecular
defects responsible for some of these predisposing conditions have been uncovered in recent
years (e.g. STAT3 mutations in HIES), the skin immune response to S. aureus infections has
not been elucidated in either healthy controls or susceptible populations. In this protocol,
we will perform exploratory evaluations of anti-staphylococcal immune responses in healthy
subjects, subjects with STAT3 mutations, and otherwise healthy subjects with a history of
recurrent staphylococcal skin infections. An additional group of subjects with other
underlying conditions of interest may be included.

The primary objective of this research is to perform in vivo and ex vivo challenges with
killed bacteria through the use of the skin blister model and keratinocyte cultures to
evaluate skin immune responses. Occasionally, a commensal fungi, such as Candida species may
also be used. We will use three experimental approaches to complete this objective: 1)
evaluation of in vivo responses in skin blisters to killed microbe exposure, 2) ex vivo
evaluation of anti-microbial responses through derivation of keratinocyte cultures from skin
blisters or biopsies, and 3) evaluation of function and immune-stimulatory ability of
commensal organisms.

Specifically, a suction blister device will be used to induce a skin blister on the forearm.
The tops of the blisters will be removed, and solutions of killed S. aureus, commensal
coagulase-negative staphylococcal species, or other Gram-negative commensals as well as
commensal fungi, such as Candida species will be applied to the blisters to stimulate
inflammatory responses. The blister fluid will then be collected at various time points over
24 hours for laboratory analysis. Baseline skin and/or nasal swabs, skin biopsies, and blood
draws will also be performed (The skin and nasal swabs may be performed at the screening or
baseline visit.). Pediatric participants may be enrolled for baseline skin and/or nasal
swabs. All research procedures will be performed at the National Institutes of Health
Clinical Center. We anticipate that the research will provide critical new information on the
human skin immune response to S. aureus that has direct relevance for the development of
vaccines, diagnostics, and therapeutics.

- INCLUSION CRITERIA:

Participants must either:

1. Have documentation of a proven or suspected immune defect or a history of invasive
infection or recurrent (2 or more) skin infections with S. aureus (patient
population); or

2. Not have evidence of an immune defect or history of invasive or recurrent S. aureus
infections (healthy volunteers).

- Participants must be between 2 and 65 years old (inclusive).

- Participants must be willing to allow storage of blood, DNA, RNA, bacterial and
fungal cultures, and other tissue samples for future research. Some research
blood may not be required of healthy volunteers, except at the discretion of the
Principal Investigator (PI).

EXCLUSION CRITERIA:

The following exclusion criteria apply to all participants:

- Current chemotherapy or underlying malignancy.

- Current oral steroids.

- Individuals with any condition that, in the opinion of the investigator,
contraindicates participation in the study will be excluded.

The following exclusion criteria apply to adult participants in the blister portion of the
study (Arm 1) only:

- Viral hepatitis B or C. Test results, including those from an outside facility or lab,
within the prior 6 months will be accepted.

- HIV positive. Test results, including those from an outside facility or lab, within
the prior 6 months will be accepted.

- Individuals on anticoagulant or anti-platelet therapy (other than aspirin or NSAIDs as
described in the protocol).

- Pregnancy.