Evidence for a disease-promoting effect of Staphylococcus aureus-derived exotoxins in atopic dermatitis.
BACKGROUND
The skin of patients with atopic dermatitis (AD) exhibits a striking susceptibility to colonization with Staphylococcus aureus. Some strains of S aureus secrete exotoxins with T-cell superantigen activity (toxigenic strains), and abnormal T-cell functions are known to play a critical role in AD.


OBJECTIVE
Our purpose was to examine the impact of superantigen production by skin-colonizing S aureus on disease severity.


METHODS
In a cross-sectional study of 74 children with AD, the presence and density of toxigenic and nontoxigenic strains of S aureus was correlated with disease severity. In a subgroup of patients the T-cell receptor Vbeta repertoire of peripheral blood and lesional T cells was investigated and correlated with individual superantigen activity of skin-colonizing S aureus.


RESULTS
Fifty-three percent of children with AD were colonized with toxigenic strains of S aureus producing staphylococcal enterotoxin C, staphylococcal enterotoxin A, toxic shock syndrome toxin-1, staphylococcal enterotoxin B, and staphylococcal enterotoxin D in decreasing frequency. Children colonized with toxigenic S aureus strains had higher disease severity compared with the nontoxigenic and S aureus-negative groups. Patients colonized with toxigenic S aureus exhibited shifts in the intradermal T-cell receptor Vbeta repertoire that correspond to the respective superantigen-responsive T-cell subsets.


CONCLUSIONS
The data demonstrate that S aureus-released exotoxins can modulate disease severity and dermal T-cell infiltration.
Bunikowski
R
R
Charité Campus Virchow-Klinikum, Humboldt University of Berlin, Department of Pediatric Pneumology and Immunology, Berlin, Germany.
Mielke
M E
ME
Skarabis
H
H
Worm
M
M
Anagnostopoulos
I
I
Kolde
G
G
Wahn
U
U
Renz
H
H
D000293:Adolescent; D000942:Antigens, Bacterial / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D003876:Dermatitis, Atopic / Q000276:immunology* / Q000473:pathology; D004768:Enterotoxins / Q000276:immunology; D005083:Exfoliatins / Q000633:toxicity*; D006801:Humans; D007223:Infant; D012720:Severity of Illness Index; D012867:Skin / Q000382:microbiology / Q000473:pathology; D013211:Staphylococcus aureus / Q000254:growth & development / Q000276:immunology; D018089:Superantigens / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000473:pathology
D000942:Antigens, Bacterial; D004768:Enterotoxins; D005083:Exfoliatins; D018089:Superantigens; C031818:enterotoxin B, staphylococcal