Differential expression of TOB/BTG family members in patients with plaque psoriasis: cross-sectional study

TOB/BTG is a family of antiproliferative proteins that play an important role in the regulation of immune responses, acting as lymphocyte activators and macrophage-mediated cytotoxicity. No previous studies have explored their role in patients with psoriasis. The aim of this study was to characterize the expression of TOB/BTG family and their co-localization in skin from patients with psoriasis. This is an exploratory, observational, and cross-sectional study that included 24 plaque psoriasis patients and 15 controls. Gene expression of TOB/BTG family was determinate by RT-PCR. Protein products of TOB/BTG were evaluated by immunohistochemistry and compared with control skin tissues. Holm-Sidak’s multiple comparisons test was performed. TOB/BTG family mRNA levels and protein expression were significantly decreased in psoriatic skin tissue compared to non-inflammatory control skin tissue. Double-positive cell TOB1/2, BTG1,2 and BTG4/CD16 expressions were found in normal control skin tissues through epidermis and dermis (p < 0.001) and lesser percentage in patients with mild, almost absent in moderate-severe plaque psoriasis. This is the first report of the TOB/BTG family gene and protein expression in skin tissues by a CD16 + subpopulation in plaque psoriasis. TOB/BTG family protein might represent a new therapeutic target among immune-mediated inflammatory diseases.