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The Effect of Bacteriophage Preparations on Intracellular Killing of Bacteria by Phagocytes. J Immunol Res 2015; 2015:482863. [PMID: 26783541 PMCID: PMC4689956 DOI: 10.1155/2015/482863] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 01/21/2023] Open
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.
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Dalmasso M, Hill C, Ross RP. Exploiting gut bacteriophages for human health. Trends Microbiol 2014; 22:399-405. [PMID: 24656964 DOI: 10.1016/j.tim.2014.02.010] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 02/19/2014] [Accepted: 02/21/2014] [Indexed: 12/26/2022]
Abstract
The human gut contains approximately 10(15) bacteriophages (the 'phageome'), probably the richest concentration of biological entities on earth. Mining and exploiting these potential 'agents of change' is an attractive prospect. For many years, phages have been used to treat bacterial infections in humans and more recently have been approved to reduce pathogens in the food chain. Phages have also been studied as drug or vaccine delivery vectors to help treat and prevent diseases such as cancer and chronic neurodegenerative conditions. Individual phageomes vary depending on age and health, thus providing a useful biomarker of human health as well as suggesting potential interventions targeted at the gut microbiota.
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Affiliation(s)
- Marion Dalmasso
- School of Microbiology, University College Cork, Cork, Ireland; Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Colin Hill
- School of Microbiology, University College Cork, Cork, Ireland; Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.
| | - R Paul Ross
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland; Teagasc Biotechnology Centre, Moorepark Food Research Centre, Fermoy, Co. Cork, Ireland
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Burrowes B, Harper DR, Anderson J, McConville M, Enright MC. Bacteriophage therapy: potential uses in the control of antibiotic-resistant pathogens. Expert Rev Anti Infect Ther 2014; 9:775-85. [DOI: 10.1586/eri.11.90] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Mills S, Shanahan F, Stanton C, Hill C, Coffey A, Ross RP. Movers and shakers: influence of bacteriophages in shaping the mammalian gut microbiota. Gut Microbes 2013; 4:4-16. [PMID: 23022738 PMCID: PMC3555884 DOI: 10.4161/gmic.22371] [Citation(s) in RCA: 152] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The human intestinal microbiota is one of the most densely populated ecosystems on Earth, containing up to 10 ( 13) bacteria/g and in some respects can be considered an organ itself given its role in human health. Bacteriophages (phages) are the most abundant replicating entities on the planet and thrive wherever their bacterial hosts exist. They undoubtedly influence the dominant microbial populations in many ecosystems including the human intestine. Within this setting, lysogeny appears to be the preferred life cycle, presumably due to nutrient limitations and lack of suitable hosts protected in biofilms, hence the predator/prey dynamic observed in many ecosystems is absent. On the other hand, free virulent phages in the gut are more common among sufferers of intestinal diseases and have been shown to increase with antibiotic usage. Many of these phages evolve from prophages of intestinal bacteria and emerge under conditions where their bacterial hosts encounter stress suggesting that prophages can significantly alter the microbial community composition. Based on these observations, we propose the "community shuffling" model which hypothesizes that prophage induction contributes to intestinal dysbiosis by altering the ratio of symbionts to pathobionts, enabling pathobiont niche reoccupation. The consequences of the increased phage load on the mammalian immune system are also addressed. While this is an area of intestinal biology which has received little attention, this review assembles evidence from the literature which supports the role of phages as one of the biological drivers behind the composition of the gut microbiota.
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Affiliation(s)
- Susan Mills
- Teagasc Food Research Centre; Moorepark; Fermoy, County Cork, Ireland
| | - Fergus Shanahan
- Alimentary Pharmabiotic Centre; University College Cork; National University of Ireland; Cork, Ireland,Department of Medicine; University College Cork; National University of Ireland; Cork, Ireland
| | - Catherine Stanton
- Teagasc Food Research Centre; Moorepark; Fermoy, County Cork, Ireland,Alimentary Pharmabiotic Centre; University College Cork; National University of Ireland; Cork, Ireland
| | - Colin Hill
- Alimentary Pharmabiotic Centre; University College Cork; National University of Ireland; Cork, Ireland,Department of Microbiology; University College Cork; National University of Ireland; Cork, Ireland
| | - Aidan Coffey
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - R. Paul Ross
- Teagasc Food Research Centre; Moorepark; Fermoy, County Cork, Ireland,Alimentary Pharmabiotic Centre; University College Cork; National University of Ireland; Cork, Ireland,Correspondence to: R. Paul Ross,
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Abstract
Although the natural hosts for bacteriophages are bacteria, a growing body of data shows that phages can also interact with some populations of mammalian cells, especially with cells of the immune system. In general, these interactions include two main aspects. The first is the phage immunogenicity, that is, the capacity of phages to induce specific immune responses, in particular the generation of specific antibodies against phage antigens. The other aspect includes the immunomodulatory activity of phages, that is, the nonspecific effects of phages on different functions of major populations of immune cells involved in both innate and adaptive immune responses. These functions include, among others, phagocytosis and the respiratory burst of phagocytic cells, the production of cytokines, and the generation of antibodies against nonphage antigens. The aim of this chapter is to discuss the interactions between phages and cells of the immune system, along with their implications for phage therapy. These topics are presented based on the results of experimental studies and unique data on immunomodulatory effects found in patients with bacterial infections treated with phage preparations.
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56
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Hartley MA, Ronet C, Fasel N. Backseat drivers: the hidden influence of microbial viruses on disease. Curr Opin Microbiol 2012; 15:538-45. [DOI: 10.1016/j.mib.2012.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 05/21/2012] [Indexed: 01/21/2023]
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Casas V, Maloy S. Role of bacteriophage-encoded exotoxins in the evolution of bacterial pathogens. Future Microbiol 2012; 6:1461-73. [PMID: 22122442 DOI: 10.2217/fmb.11.124] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Recent advances in metagenomics research have generated a bounty of information that provides insight into the dynamic genetic exchange occurring between bacteriophage (phage) and their bacterial hosts. Metagenomic studies of the microbiomes from a variety of environments have shown that many of the genes sequenced are of phage origin. Among these genes are phage-encoded exotoxin genes. When phage that carry these genes infect an appropriate bacterial host, the bacterium undergoes lysogenic conversion, converting the bacterium from an avirulent strain to a pathogen that can cause human disease. Transfer of the exotoxin genes between bacteria has been shown to occur in marine environments, animal and human intestines and sewage treatment plants. Surprisingly, phage that encode exotoxin genes are commonly found in environments that lack the cognate bacteria commonly associated with the specific toxin-mediated disease and have been found to be associated with alternative environmental bacterial hosts. These findings suggest that the exotoxin genes may play a beneficial role for the bacterial host in nature, and that this environmental reservoir of exotoxin genes may play a role in the evolution of new bacterial pathogens.
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Affiliation(s)
- Veronica Casas
- Center for Microbial Sciences, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA
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58
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Abstract
Bacteriophage-based medical research provides the opportunity to develop targeted nanomedicines with heightened efficiency and safety profiles. Filamentous phages also can and have been formulated as targeted drug-delivery nanomedicines, and phage may also serve as promising alternatives/complements to antibiotics. Over the past decade the use of phage for both the prophylaxis and the treatment of bacterial infection, has gained special significance in view of a dramatic rise in the prevalence of antibiotic resistance bacterial strains. Two potential medical applications of phages are the treatment of bacterial infections and their use as immunizing agents in diagnosis and monitoring patients with immunodeficiencies. Recently, phages have been employed as gene-delivery vectors (phage nanomedicine), for nearly half a century as tools in genetic research, for about two decades as tools for the discovery of specific target-binding proteins and peptides, and for almost a decade as tools for vaccine development. As phage applications to human therapeutic development grow at an exponential rate, it will become essential to evaluate host immune responses to initial and repetitive challenges by therapeutic phage in order to develop phage therapies that offer suitable utility. This paper examines and discusses phage nanomedicine applications and the immunomodulatory effects of bacteriophage exposure and treatment modalities.
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A study to evaluate the effect of nootropic drug—Piracetam on DNA damage in leukocytes and macrophages. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2011; 726:66-74. [DOI: 10.1016/j.mrgentox.2011.08.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 08/01/2011] [Accepted: 08/26/2011] [Indexed: 11/17/2022]
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Borysowski J, Wierzbicki P, Kłosowska D, Korczak-Kowalska G, Weber-Dąbrowska B, Górski A. The Effects of T4 and A3/R Phage Preparations on Whole-Blood Monocyte and Neutrophil Respiratory Burst. Viral Immunol 2010; 23:541-4. [DOI: 10.1089/vim.2010.0001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Jan Borysowski
- Department of Clinical Immunology, Transplantation Institute, Warsaw Medical University, Warsaw, Poland
| | - Piotr Wierzbicki
- Department of Clinical Immunology, Transplantation Institute, Warsaw Medical University, Warsaw, Poland
| | - Danuta Kłosowska
- Department of Clinical Immunology, Transplantation Institute, Warsaw Medical University, Warsaw, Poland
| | - Grażyna Korczak-Kowalska
- Department of Clinical Immunology, Transplantation Institute, Warsaw Medical University, Warsaw, Poland
- Department of Immunology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Beata Weber-Dąbrowska
- Laboratory of Bacteriophages, Hirszfeld Institute of Immunology and Experimental Therapy, Wrocław, Poland
| | - Andrzej Górski
- Department of Clinical Immunology, Transplantation Institute, Warsaw Medical University, Warsaw, Poland
- Laboratory of Bacteriophages, Hirszfeld Institute of Immunology and Experimental Therapy, Wrocław, Poland
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61
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Letkiewicz S, Międzybrodzki R, Kłak M, Jończyk E, Weber-Dąbrowska B, Górski A. The perspectives of the application of phage therapy in chronic bacterial prostatitis. ACTA ACUST UNITED AC 2010; 60:99-112. [DOI: 10.1111/j.1574-695x.2010.00723.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Zimecki M, Artym J, Kocięba M, Weber-Dąbrowska B, Borysowski J, Górski A. Prophylactic effect of bacteriophages on mice subjected to chemotherapy-induced immunosuppression and bone marrow transplant upon infection with Staphylococcus aureus. Med Microbiol Immunol 2009; 199:71-9. [DOI: 10.1007/s00430-009-0135-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Indexed: 12/20/2022]
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Letkiewicz S, Miedzybrodzki R, Fortuna W, Weber-Dabrowska B, Górski A. Eradication of Enterococcus faecalis by phage therapy in chronic bacterial prostatitis--case report. Folia Microbiol (Praha) 2009; 54:457-61. [PMID: 19937220 DOI: 10.1007/s12223-009-0064-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 05/27/2009] [Indexed: 10/20/2022]
Abstract
The treatment of three patients suffering from chronic bacterial prostatitis who were qualified for an experimental phage therapy protocol managed at the Phage Therapy Unit in Wrocław is described. They had previously been treated unsuccessfully with long-term targeted antibiotics, autovaccines, and laser biostimulation. Rectal application of phage lysates targeted against Enterococcus faecalis cultured from the prostatic fluid gave encouraging results regarding bacterial eradication, abatement of clinical symptoms of prostatitis, and lack of early disease recurrence.
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Affiliation(s)
- S Letkiewicz
- Urological and Andrological Clinic UROGEN, 42-600, Tarnowskie Góry, Poland.
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64
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Zimecki M, Artym J, Kocieba M, Weber-Dabrowska B, Borysowski J, Górski A. Effects of prophylactic administration of bacteriophages to immunosuppressed mice infected with Staphylococcus aureus. BMC Microbiol 2009; 9:169. [PMID: 19686585 PMCID: PMC2741470 DOI: 10.1186/1471-2180-9-169] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Accepted: 08/17/2009] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Bacteriophages can be successfully applied to treat infections caused by antibiotic-resistant bacteria. Until now no attempts have been undertaken to treat infections in immunosuppressed patients with phages. In this work we investigated the prophylactic efficacy of specific bacteriophages in CBA mice treated with cyclophosphamide (CP) and infected with Staphylococcus aureus. RESULTS High numbers of bacterial colony-forming units in the organs as well as elevated tumor necrosis factor and interleukin-6 serum concentrations in CP-treated and S. aureus-infected mice were significantly lowered upon application of phages. The phages markedly increased the percentage of circulating neutrophils and immature cells from the myelocytic and lymphocytic lineages in CP-treated, S. aureus-infected mice as well as of myelocytes and immature neutrophils in the bone marrow. In addition, phages stimulated in such mice generation of specific agglutinins against S. aureus. CONCLUSION Application of specific phages to immunosuppressed mice prior to infection with S. aureus proved very effective, suggesting a potential benefit of phage therapy in immunocompromised patients experiencing bacterial infections.
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Affiliation(s)
- Michał Zimecki
- Institute of Immunology and Experimental Therapy, Polish Academy of Science, Wrocław, Poland.
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65
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Kurzepa A, Dabrowska K, Skaradziński G, Górski A. Bacteriophage interactions with phagocytes and their potential significance in experimental therapy. Clin Exp Med 2009; 9:93-100. [PMID: 19184327 PMCID: PMC7088290 DOI: 10.1007/s10238-008-0027-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Accepted: 12/02/2008] [Indexed: 11/05/2022]
Abstract
Bacteriophages are among the most numerous creatures on earth and they are omnipresent. They are thus in constant natural contact with humans and animals. However, the clinical and technological use of bacteriophages has also become more frequent, which is why all aspects of phage-mammal interactions need to be explored. Bacteriophages are able to interact with mammalian phagocytes. They may inhibit the phagocytosis of bacteria, but they may also undergo phagocytosis themselves. The ability of bacteriophages to reduce reactive oxygen species production by polymorphonuclear leukocytes in the presence of bacteria or their endotoxins was also confirmed. Studies show that the high immunogenicity of bacteriophages may also be employed in anti-tumor treatment. The present knowledge of phage interactions with cellular components of the mammalian immune system is sparse and insufficient, especially considering the increasing interest in the application of these viruses in human life. We believe that continuation of such research is indispensable.
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Affiliation(s)
- Aneta Kurzepa
- L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. Weigla 12, 53-114 Wrocław, Poland.
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66
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Verma V, Harjai K, Chhibber S. Characterization of a T7-like lytic bacteriophage of Klebsiella pneumoniae B5055: a potential therapeutic agent. Curr Microbiol 2009; 59:274-81. [PMID: 19484297 DOI: 10.1007/s00284-009-9430-y] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Accepted: 05/08/2009] [Indexed: 10/20/2022]
Abstract
Characterization of bacteriophages to be used prophylactically or therapeutically is mandatory, as use of uncharacterized bacteriophages is considered as one of the major reasons of failure of phage therapy in preantibiotic era. In the present study, one lytic bacteriophage, KPO1K2, specific for Klebsiella pneumoniae B5055, with broad host range was selected for characterization. As shown by TEM, morphologically KPO1K2 possessed icosahedral head with pentagonal nature with apex to apex head diameter of about 39 nm. Presence of short noncontractile tail (10 nm) suggested its inclusion into family Podoviridae with a designation of T7-like lytic bacteriophage. The phage growth cycle with a latent period of 15 min and a burst size of approximately 140 plaque forming units per infected cell as well as a genome of 42 kbps and structural protein pattern of this bacteriophage further confirmed its T7-like characteristics. Phage was stable over a wide pH range of 4-11 and demonstrated maximum activity at 37 degrees C. After injection into mice, at 6 h, a high phage titer was seen in blood as well as in kidney and urinary bladder, though titers in kidney and urinary bladder were higher as compared to blood. Phage got cleared completely in 36 h from blood while from kidneys and urinary bladder its clearance was delayed. We propose the use of this characterized phage, KPO1K2, as a prophylactic/therapeutic agent especially for the treatment of catheter associated UTI caused by Klebsiella pneumoniae.
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Affiliation(s)
- Vivek Verma
- Department of Microbiology, Panjab University, Chandigarh, 160014, India
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67
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A retrospective analysis of changes in inflammatory markers in patients treated with bacterial viruses. Clin Exp Med 2009; 9:303-12. [PMID: 19350363 DOI: 10.1007/s10238-009-0044-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 02/25/2009] [Indexed: 12/19/2022]
Abstract
Bacteriophages are increasingly considered an alternative to antibiotics for the treatment of bacterial infections. Clinical improvement may be associated with a lowering of inflammatory markers during the antibiotic treatment of bacterial infections. Some experimental data suggest that phage treatment may have anti-inflammatory properties. We present a retrospective analysis of C-reactive protein (CRP) serum concentration, erythrocyte sedimentation rate (ESR), and white blood cell count (WBC) measured in patients with chronic, symptomatic, antibiotic therapy-resistant bacterial infections who qualified for phage treatment within the protocol "Experimental Phage Therapy of Antibiotic Therapy-Resistant Infections, Including MRSA Infections". Data collected from 37 patients with osteomyelitis (with or without metal implants or joint endoprosthesis) or skin and soft tissue or lower respiratory tract infection induced by, in the majority of cases, S. aureus were analyzed. Phage preparations (natural phage lysates) were administered orally (one 10-ml ampoule three times daily after neutralization of gastric juice with 10 ml of dihydroxyaluminium sodium carbonate) and/or locally (one ampoule two times daily for wet compresses or irrigation of a fistula). No significant changes in mean serum levels of CRP measured after 5-8 days of phage administration were observed compared with the baseline CRP levels measured before therapy (35.7 vs. baseline 38.6 mg/l, n = 11). However, a significant decrease in mean CRP values measured later, between days 9 and 32, was noted (16.1 vs. baseline 23.3 mg/l, n = 26, P < 0.05). Similar tendencies were observed in the changes in mean WBC values, but mean ESR in the patients before, in the early phase, and later during therapy did not change significantly. This is the first report suggesting that the application of phage preparations may probably influence and diminish the inflammatory reaction that accompanies bacterial infection.
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68
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Letarov A, Kulikov E. The bacteriophages in human- and animal body-associated microbial communities. J Appl Microbiol 2009; 107:1-13. [PMID: 19239553 DOI: 10.1111/j.1365-2672.2009.04143.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Felix d'Herelle first demonstrated, about 90 years ago, the presence of bacteriophages in human and animal body microbiota. Our comprehension of the impact of naturally occurring bacteriophages on symbiotic bacteria, and of their role in general homeostasis of macro-organism, nevertheless remains quite fragmentary. Analysis of data in various human- and animal body-associated microbial systems on phage occurrence, diversity, host specificity and dynamics, as well as host occurrence, specificity and dynamics, suggests that mechanisms which stabilize phage-bacteria coexistence are not identical for either different species or different body sites. Regulation by phage infection instead probably depends on specific physical, chemical and biological conditions, e.g. pH, nutrient densities, host prevalence, relation to mucosa and other surfaces and presence of phage inhibiting substances. In some animal species intestinal bacteriophages thus appear to exert significant selective pressure over at least some resident bacterial populations, resulting in phages playing important roles in the self-regulation of these microbial systems while at the same time contributing to maintenance of bacterial diversity (i.e. 'killing the winner'). Emerging data additionally suggest that bacteriophage particles could play roles in regulating the immune reactions of the macro-organism. Alternatively, for many systems links between phages and community characteristics have not been established.
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Affiliation(s)
- A Letarov
- Winogradsky Institute of Microbiology RAS, Moscow, Russia.
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