Overexpression of ITGB3 in Peripheral Blood Mononuclear Cells of Relapsing-Remitting Multiple Sclerosis Patients

Multiple sclerosis (MS), the most prevalent chronic inflammatory, demyelinating and neurodegenerative disease of the central nervous system in young adults, exhibits marked sexual dimorphism, with a 3:1 female-to-male ratio, but more severe symptoms and greater neurological damage in males. Increasing attention has focused on identifying circulating molecules that reflect inflammatory activity within the central nervous system and could clarify the mechanisms underlying MS. Pleiotrophin (PTN), a cytokine implicated in autoimmune and neurological diseases, is significantly elevated in patients with relapsing-remitting MS (RRMS). To explore the potential contribution of PTN and its receptors to neuroinflammatory signaling, we quantified the mRNA expression of PTN receptors in peripheral blood mononuclear cells from RRMS patients compared to untreated RRMS patients and healthy control subjects. We further performed an in silico molecular docking and molecular dynamics analysis to assess the possible functional significance of PTN-receptor interactions. Our results show a significant overexpression of integrin subunit beta-3 (ITGB3) mRNA in peripheral blood mononuclear cells from RRMS patients compared to healthy control subjects. Molecular docking shows that PTN could binds to the metal ion-dependent adhesion site domain of ITGB3 via Mg²⁺/Ca²⁺-mediated stabilization and has a higher binding affinity than fibrinogen, the canonical endogenous ligand. These findings suggest that ITGB3 could be a dynamically regulated integrin receptor in RRMS that may participate in PTN-driven neuroinflammatory pathways in peripheral blood immune cells, influenced by disease stage, sex, and immunotherapy. While our results support the biological plausibility of PTN-ITGB3 engagement, they remain hypothesis-generating and require functional validation. The integration of molecular expression data and computational modeling underscores the potential involvement of ITGB3 as a possible participant in MS and warrants further investigation of its clinical and mechanistic role.