Identification of new potential autoantigens involved in the development of experimental autoimmune prostatitis

MOTRICH, RD; DROUOT, L; BRESER, ML; SANCHEZ, L; BOYER, O; RIVERO, VE

Los Cocos, Cordoba

Congreso; LXI Reunión Científica de la SAI; 2013

Sociedad Argentina de Inmunologia

Chronic Non Bacterial Prostatitis is a highly prevalent disease of unclear etiology and empiric treatment. Autoimmunity has been proposed as a cause. Aged NOD and NOD-AIRE-/- mice develop autoimmune prostatitis spontaneously. Using a proteomic approach we aimed to identify new prostate autoantigens recognized by the immune response of these animals. Mouse prostate protein extracts were separated by two-dimensional gel electrophoresis (PI: pH:3-10). Proteins were transferred to nitrocellulose membranes and blotted against serum samples from aged male NOD (Group P1), NOD-AIRE -/- (Group P2) and young adult NOD mice (Group C) as controls. Immunoreactive bands were isolated from gels and subjected to mass spectrometry analysis. Three positive immunoreactive bands were detected when assaying serum samples of animals from Groups P1 and P2. Mass spectrometry analyses identified bands as 3 proteins that are androgen-dependent and normally expressed in the adult mouse prostate: (1) Transgelin, which belongs to the SVSII protein family, is a cytoskeleton protein normally expressed in prostate epithelial cells and downregulated in prostate cancer; (2) Seminal Vesicle Secretory protein 4 (SVS4), which also belongs to the SVSII protein family, is a component of seminal plasma and whose orthologous human protein Semenogelin 1 is recognized by the immune response from chronic prostatitis patients; and (3) Peroxiredoxin 1, a chaperon protein involved in the induction of prostate inflammation, secreted by prostate tumor cells and an endogenous ligand of TLR4 that induces the secretion of TNF-alpha, Il-6 and HIF-1-mediated VEGF. In this work, we identified three new autoantigens recognized by the immune response of animals that spontaneously develop autoimmune prostatitis. The identification of new autoantigens potentially relevant for the humane disease is important for the improvement of the current understanding of the physiopathology and for the development of effective new therapies.