Serum levels of the Th1 promoter IL-12 and the Th2 chemokine TARC are elevated in erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis and correlate with soluble Fas ligand expression. An immunoenzymatic study from the Italian Group of Immunopathology.

BACKGROUND: No data exist as to Th2 chemokines in erythema multiforme (EM) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). OBJECTIVE: To evaluate thymus- and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC) and regulated upon activation, normal T-lymphocyte-expressed and secreted chemokine (RANTES) expression in EM and SJS/TEN and to correlate with the serum levels of the Th1 promoter interleukin (IL)-12 and soluble Fas ligand (sFasL). MATERIALS AND METHODS: IL-12, sFasL, TARC, MDC and RANTES expression were analyzed by ELISA techniques in 31 untreated EM (n = 24) or SJS/TEN (n = 7) patients and in 28 healthy donors (HD). RESULTS: EM and SJS/TEN exhibited significantly higher levels of TARC, IL-12 and sFasL with respect to HD. TARC upregulation paralleled both the IL-12 (p = 0.0225) and sFasL increase (p = 0.0194). CONCLUSIONS: Our results support a role of TARC in the pathophysiology of EM/SJS/TEN and confirm the coexistence of a Th2 response in addition to the predominant Th1 profile.