The Effect of Bacteriophage Preparations on Intracellular Killing of Bacteria by Phagocytes

Abstract

Intracellular killing of bacteria is one of the fundamental mechanisms against invading pathogens. Impaired intracellular killing of bacteria by phagocytes may be the reason of chronic infections and may be caused by antibiotics or substances that can be produced by some bacteria. Therefore, it was of great practical importance to examine whether phage preparations may influence the process of phagocyte intracellular killing of bacteria. It may be important especially in the case of patients qualified for experimental phage therapy (approximately half of the patients with chronic bacterial infections have their immunity impaired). Our analysis included 51 patients with chronic Gram-negative and Gram-positive bacterial infections treated with phage preparations at the Phage Therapy Unit in Wroclaw. The aim of the study was to investigate the effect of experimental phage therapy on intracellular killing of bacteria by patients' peripheral blood monocytes and polymorphonuclear neutrophils. We observed that phage therapy does not reduce patients' phagocytes' ability to kill bacteria, and it does not affect the activity of phagocytes in patients with initially reduced ability to kill bacteria intracellularly. Our results suggest that experimental phage therapy has no significant adverse effects on the bactericidal properties of phagocytes, which confirms the safety of the therapy.

Phages and Immunomodulation

“…The effect of phage therapy on IKB has been studied by Jończyk-Matysiak et al [31]. As could be expected, IKB of patients prior to therapy was generally reduced while the therapy did not cause further reduction in IKB of a standard Escherichia coli B strain.…”

Pf Bacteriophage and Their Impact on Pseudomonas Virulence, Mammalian Immunity, and Chronic Infections

“…There are also suggestions that some species of phage may promote the opsonization of bacteria by adhering to the bacterial surface and acting as a target for antibody binding (157). In addition, there are reports that phages may be induced when their bacterial host is phagocytosed, lysing the bacteria and promoting clearance (149,158). Together, these data suggest that lytic phages may promote opposite effects on bacterial clearance compared to Pf.…”

Phage Therapy: Combating Infections with Potential for Evolving from Merely a Treatment for Complications to Targeting Diseases

“…Our data on monitoring phagocytosis by neutrophils and monocytes of patients on phage therapy suggest that the therapy may instead correct existing deficiencies in phagocyte functions (see above). In fact, we have shown that phages – both in vitro and in vivo – do not adversely affect the ability of phagocytes to kill bacteria – both standard strains as well as specific pathogens isolated from patients ( Jończyk-Matysiak et al, 2015 ). Also, phages do not impair migratory activity of human phagocytes in vitro ( Kurzępa, 2011 ), whereas they may markedly diminish tissue infiltration with those cells at the foci of inflammation ( Górski et al, 2006a ; Miernikiewicz et al, 2016 ).…”