Reduction of RANTES expression in lesional psoriatic skin after narrow band ultraviolet therapy: a possible marker of therapeutic efficacy.

Background: The regulated upon activation, normal T cell expressed and secreted (RANTES) production in psoriatic lesions may amplify the inflammation in these lesions. Narrow band ultraviolet B (NB-UVB), a therapeutic modality for psoriasis, affects the expression of inflammatory cytokines and chemokines.
Objective: Our aim was to evaluate RANTES mRNA expression in skin lesions of psoriasis before and after NB-UVB phototherapy.
Methods: This study included 25 psoriatic patients who received 24 sessions of NB-UVB. Skin biopsies were taken before and after phototherapy for real time PCR evaluation of RANTES mRNA.
Results: The relative quantitation values (RQ) of RANTES mRNA expression was significantly reduced after treatment. A significant negative correlation was found between pre-treatment RQ RANTES mRNA expression and post-treatment PASI score. We found a significant negative correlation between dRQ RANTES mRNA expression (difference between RQ RANTES mRNA expression before and after phototherapy) and PASI score after phototherapy. We found significant negative correlations between pre-treatment RQ RANTES mRNA expression and both initial response session number and total NB-UVB dose at the end of phototherapy.
Conclusion: NB-UVB reduces RANTES mRNA expression in psoriatic lesions. Pre-treatment RQ RANTES mRNA expression could be considered as a marker for clinical improvement and NB-UVB phototherapy efficacy.