Composition of Bacteriophages for Therapeutic and Prophylactic Use in Monkeys.

Keeping rhesus monkeys as laboratory animals requires timely prevention and treatment of infections, including diseases of bacterial etiology. Based on our own studies of the microflora of healthy and sick monkeys, as well as analysis of published reports, we identified clinically significant representatives of pathogenic and opportunistic bacteria: E. coli, Staphylococcus aureus, Klebsiella spp., Proteus spp. The isolates of these bacterial species and genera circulating in monkeys kept in the enclosure were isolated, four virulent bacteriophage strains with a wide spectrum of lytic activity against these isolates were selected and newly isolated. The composition based on virulent bacteriophage strains was tested on monkeys with assessment of its safety and its dynamics of detection of phage-specific DNA.

Bacteriophage Cocktail Effectively Prolonging the Shelf-Life of Chilled Fish.

We developed a technological accessory bacteriophage-based preparation and a method for phage-mediated bioprocessing for elimination of pathogenic microorganisms from the surface of fresh fish and for prolongation of the shelf-life of chilled hydrobionts. Specimens of rainbow trout (Salmo irideus) served as the objects of the study carried out at a fish-processing plant in the Republic of Karelia. The specimens were decontaminated by a bacteriophage cocktail containing six original virulent phage strains characterized by their pheno- and genotypical properties. A new method of biodecontamination (plunging the rainbow trout for 30 sec into a solution of bacteriophage cocktail (bacteriophage titers ≥108 PFU/ml) delayed bacterial degradation of hydrobionts by 3 days. The use of the new method for decontamination of food half-products - phage-mediated bioprocessing - promoted preservation of the initial ecological purity, nutritive value, and taste of the products and prolonged their shelf-life in comparison with the actual standards.

Phagebiotics in treatment and prophylaxis of healthcare-associated infections.

We have developed a phagebiotic composition using 8 virulent bacteriophages (2 strains of each species) which are able to lyse Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. The unique character of the developed composition is ensured by particular properties of each bacteriophage comprising the preparation, including their range of lytic activity toward specific bacterial pathogens, morphology of their plaques, cycle of their development, restriction profile of their DNAs, specificity of their genomes (based on complete genome sequencing), and other properties. The preparation did not produce any signs of acute or chronic intoxication in the experimental animals. Therapeutic and prophylactic efficiency of the phagebiotic composition was demonstrated in the prevention and treatment of the experimental acute K. pneumoniae infection in mice. The investigations have shown that the preparation possesses a high therapeutic efficiency and is highly competitive with ciprofloxacin which is very effective against the infective strain K. pneumoniae. Our small-scale clinical trial was aimed to evaluate therapeutic effectiveness of the phagebiotic composition in an epidemiological emergency situation in an intensive care unit, caused by multi-resistant strains of Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa. Seventy nine per cent of the initial samples from 14 patients' endotracheal aspirate, blood and urine were contaminated. Twenty-four hours after the 3-day phage therapy (20 ml of cocktail at a titer for each phage 108 pfu/ml were introduced intragastrically through a tube once a day) contamination level dropped to 21%. Hence the obtained results enabled us to create a new phagebiotic composition that may be used as an alternative to antibiotics to treat these healthcare-associated infections.