Synthetic thymic hexapeptide in the correction of alterations of antibacterial immune defense and normalization of the profile of proinflammatory cytokines in immunocompromized Children with local unlimited acute peritonitis

The study of dysregulatory disorders of the immune system underlying the immunopathogenesis of severe purulent-inflammatory diseases (PIDs) is important for development of new therapeutic tactics of restoring antibacterial defense. Acute peritonitis (AP) is a severe PID of the abdominal cavity, the course of which are dependent on the treatment, cytokine balance and adequate functioning of the immunity. Objective: to evaluate the modulating effects on the immune system and the levels of proinflammatory cytokines of the synthetic thymic hexapeptide, active substance of Imunofan, included in the complex postoperative treatment (CPOT) of immunocompromised children with local AP. Clinical and immunological examination of 20 immunocompromised children aged 5–12 years with local AP was carried out before (study group 1, SG1) and after (study group 1a, SG1a) CPOT including synthetic thymic hexapeptide (Arginyl-alpha-AspartylLysyl-Valyl-Tyrosyl-Arginine, НР), alongside 20 conditionally healthy children (comparison group, SG). The content of T and B lymphocytes, natural killer cells (NK), levels of serum pro-inflammatory cytokines IL-1β, IL-6, TNFα, IL-8, IL-18, phagocytic and microbicidal activity of neutrophils (NG) were assessed. In SG1, before treatment, a decrease in the number of T lymphocytes, T helpers, CTL-lymphocytes, NK and an increase in the level of B lymphocytes was revealed. Defects in the effector functions of NG were determined: impaired bacterial antigen killing and decreased NADPH oxidase activity. It was established that in case of AP in immunocompromised children, the cytokine profile is characterized by overproduction of studied proinflammatory and neutrophil-associated cytokines. After complex treatment including immunomodulatory therapy, there was a restoration of the content of T lymphocytes, T helper cells, TCTL lymphocytes, an increase in the number of NK and decrease in the level of B lymphocytes. In addition, regression of the levels of inflammatory, including neutrophil-associated, cytokines and emergence of effector functions of NG due to restoration of NADPH oxidases activity, was noted. Thus, the restoration of immunological parameters in AP leads to earlier regression of the purulent-inflammatory process in the abdominal cavity and to the absence of postoperative complications. The clinical and immunological effects of the immunomodulatory therapy program with inclusion of the drug based on HP determines the feasibility of its use in the postoperative period in immunocompromised children with local AP.