Serum protein electrophoretic profile changes in West Nile virus-naturally infected horses

•Serum protein electrophoretic profiles were determined in WNV-infected horses.•Horses with encephalitis had higher α2-globulin than asymptomatic and naïve horses.•Asymptomatically infected horses were characterized by higher γ-globulin.•Naïve horses had lower total protein and globulin levels than infected horses.•Albumin-to-globulin ratios were significantly lower in horses with encephalitis. Serum protein electrophoresis (SPE) is widely used to evaluate protein changes associated with several pathologies, aiming to assist clinical diagnosis. This study determines, for the first time, SPE profile changes in West Nile virus-naturally infected horses. Sixty horses with different clinical and infection status (encephalitis, asymptomatic infection, and immunologically naïve) were included. Total protein concentrations were determined via an automated biuret method and SPE was performed using a cellulose acetate membrane-based automated system. Statistical analysis revealed significantly higher total protein between both infected horse groups (encephalitis, asymptomatic) and naïve controls. Horses with encephalitis had higher globulin and α2-globulin levels than the other two groups (asymptomatic, naïve), along with lower albumin percentage and albumin-to-globulin ratio. Furthermore, γ-globulin levels were significantly higher in asymptomatically infected compared to control horses. These findings highlight the diagnostic value of SPE profile determination, assisting the clinicians, and providing the grounds for further research.