Stimulation of Phagocytosis and Production of Antibodies against Canine Herpesvirus Type 1 by Pidotimod (Adimod<sup>TM</sup>)

Abstract

Neutrophils are the most important circulating phagocytes. Circulating monocytes and precursors of tissue macrophages also have the ability to phagocytize. Pidotimod (ADIMOD™) exerts immunostimulatory and immunoregulatory effects through the stimulation and regulation of cellular immune responses by lymphocytes Canine herpesvirus (CHV) mainly affect puppies between the first and second weeks of age, causing high morbidity in the litter. To date, there is only one commercial vaccine in Europe to prevent disease. In this work, inactivated CHV cultures were inoculated in rabbits, adsorbed and not adsorbed to chitosan nanoparticles. Phagocytosis in the presence or absence of specific antibodies was measured. Response of virus neutralizing antibodies was also evaluated. Adimod™ enhanced the nonspecific and specific phagocytotic response. The association of the virus to the nanoparticles increased the phagocytic ability of blood cells; however, Adimod™ alone had a greater effect on phagocytic activity and generated a stronger immune response that corresponded to the increased phagocytosis (p < 0.05). Moreover, the level of neutralizing antibodies was higher and increased more rapidly when Adimod™ was used.