Vol 6, No 4 (2016)
- Year: 2016
- Published: 06.12.2016
- Articles: 15
- URL: https://iimmun.ru/iimm/issue/view/27
- DOI: https://doi.org/10.15789/2220-7619-2016-4
Full Issue
REVIEWS
«CANDIDATUS MIDICHLORIA MITOCHONDRII»: A NEW MEMBER OF ORDER RICKETTSIALES, ENDOSYMBIONT OF IXODES RICINUS TICK
Abstract
«Candidatus Midichloria mitochondrii» is the sheep tick Ixodes ricinus endosymbiont. This unique bacteria can occupy and persist within the mitochondria of animals. I. ricinus is an important vector of human pathogens in natural focal of infections. «Candidatus M. mitochondrii» found in the intermembrane space of mitochondria and in the cytoplasm of ovarian cells in 100% females of I. ricinus. The bacteria contain flagella in the salivary glands of ticks. «Candidatus M. mitochondrii» has two groups of unique genes for the members of the order Rickettsiales (cbb3 cytochrome oxidase and flagellin), which allows it to play an important role in embryogenesis of the I. ricinus ticks and cause seroconversion in 58% of patients after ticks bloodsucking. This bacterium formed MALOs group (midichloria and like organisms) with genetically closely related organisms which demonstrated a association with a wide range of host from arthropods to ciliates, amoebae, sponges, fish and various animals and humans. Now there is no data about replication the «Candidatus M. mitochondrii» in humans and pathogenicity of this microorganism. Although a high percentage of seropositive samples obtained from patients after bloodsucking of I. ricinus in anamnesis, this bacterium cannot yet be regarded as responsible for the pathology as known human pathogenic from order Rickettsi-ales (Rickettsia, Anaplasma and Ehrlichia spp.). Needed to reconsider the attitude to an immune response to the saliva of I. ricinus, taking into account the potential impact of «Candidatus M. mitochondrii». It is considered highly possible role of this bacterium in the immune response and immunomodulation in humans with bloodsucking of I. ricinus in anamnesis. DNA of «Candidatus M. mitochondrii» was the first time detected in I. ricinus ticks from European part of Russia.
EFFECT BY INTESTINAL MICROBIOM ON THE PROGRESSION OF VIRAL HEPATITIS
Abstract
According to the modern concepts an intestinal microbiome has a significant effect on the functioning of the whole body including the immune system, digestive tract and liver in particular. This review displays current understanding of the intestinal microbiome impacting on the progression of chronic viral hepatitis caused by HCV- and HBV-infection, as well as changes in bowel microbiocenosis features depending on the duration of chronic process in the liver. It is indicated that chronic hepatitis to cirrhosis progression is accompanied by Bifidobacterium and strains of lactic acid (Lactobacillus, Pediococcus, Leuconostoc, Weissella) number decreasing and overgrowth of opportunistic species such as Enterococcaceae, Veillonellaceae, Enterobactericeae, Candida spp., Clostridia spp. This phenomena caused by PAMPs entry into the bloodstream including various types of toxins playing a role in liver immune inflammation processes progression. Thus patients with HBV and HCV infection are increased the number of CD4+, CD25+ in the blood and liver significantly, FOXP3+ Treg cell providing an immunosuppressive effect, and the function of specific CD8 lymphocytes is reduced and insufficient leveling virus significantly. Microbial imbalance has a negative effect on the biosynthesis of bile acids and sterolbiom functioning of our body as a result of changes in the balance between Bacteroides/Firmicutes, overgrowth of pathogenic and opportunistic Enterobacteriaceae, Veillonellaceae, Alcaligeneaceae and Porphyromonadaceae, Clostridium cluster XIVa, Helicobacter spp. and Clostridium difficile. These toxins formation and various carcinogenic metabolites from these strains leads to the inflammation development in the intestines and as a consequence to the progression of the inflammatory process in the liver. In turn, the reduction in the bacteria number producing short-chain fatty acid contributes to intestinal colonization by pathogenic representatives Gracilicutes (Salmonella, Shigella, enterohaemorrhagic E. coli) and Firmicutes (Clostridia), the toxins having a direct toxic effect on the liver. It is examined a little-studied question about a possible cofactor effect of enteric viruses (rotavirus, adenovirus, poliovirus type 1, Coxsackie virus, ECHO) and bacteria (Shigella, Salmonella, diarrheagenic E. coli, C. jejuni) on the progression of chronic hepatitis. In view of the above, it is necessary to study in further detailed the influence of the intestinal microbiome on the progression of chronic hepatitis HBV/HCV etiology in order to develop a comprehensive approach to treatment and reduce the risk of adverse outcomes in patients.
ORIGINAL ARTICLES
THE NEW METALL-BETA-LACTAMASE’S INHIBITOR EFFICACY IN A MODEL SYSTEM IN VITRO
Abstract
The Enterobacteriaceae antibiotics resistance depends on a combination of several mechanisms, such as the beta-lactamases overproduction, the microbial cell reduction outer membrane permeability (usually associated with loss of protein porin), the presence of efflux systems. Particularly noteworthy are the metallo-beta-lactamases (MBL) whose presence causes resistance of gram-negative microorganisms to all beta-lactam antibiotics (in some cases except aztreonam). Currently there are no MBL inhibitors permitted for use in the clinic. The effective inhibitors search for carbapenem-resistant bacteria’ MBL authorized for use in the clinic and reinforcing effects of carbapenems, served as the basis for the present study. The work was carried out in three stages: 1) creating a model system using a standard enzyme reagent metallo-beta-lactamase P. aeruginosa recombinant expressed in E. coli, to evaluate the increasing of minimal inhibitory concentrations (MIC) of carbapenems against previously sensitive Gram-negative microorganisms strains in vitro;
2) evaluation of MBL promising inhibitors in the presence of the same standard enzyme reagent; 3) evaluation of the ability of the identified inhibitors increase the carbapenems effects against clinical isolates of Gram-negative microorganisms producing MBL, in terms of the their MIC and fractional inhibitory concentration index (FIC index). The checkerboard array was modified to evaluate the combined use of carbapenems and potential MBL inhibitor — a drug from the group of bisphosphonates — etidronic acid. Using a standard enzyme reagent metallo-beta-lactamase P. aeruginosa recombinant expressed in E. coli, we created a model system that allows to assess the prospects of new inhibitors MBL gram-negative microorganisms. A dose-dependent effect of increasing the meropenem level MIC from reagent MBL quantity in a model system against previously antibiotic sensitive reference strains of microorganisms was revealed. MBL enzyme inactivation was noted in the presence of even small doses of bisphosphonate, in the tests the appearance of logarithmic phase of P. aeru ginosa ATCC 27853 growth was shown delayed up to 12 hours compared to the control. In this case the maximum dose of etidronic acid 50 000–100 000 μg/ml completely inhibited the MBL, there was no a log phase microbe’s growth due to the effect of meropenem on the reference level of sensitivity (2 μg/ml). The synergistic effect (FIC index < 0.5) of combined meropenem with etidronic acid use was identified against clinical isolates Gram-negative microorganisms resistant to carbapenems and producing MBL, wherein the enhancing action of the antibiotic was more 8–512 times compared with the initial MIC levels.
HUMAN PAPILLOMA VIRUS IMMUNOGEN CREATION ON THE BASE OF CHIMERIC RECOMBINANT PROTEIN L2E7
Abstract
The cervical cancer is one of the most common diseases in world. This malignancy is the seventh highest prevalence oncological disease worldwide and the second highest prevalence oncological disease of women in the world. Meanwhile women need to be infected by human papilloma virus (HPV) is absolutely necessary for it further evolution, HPV DNA was found in 99.97% cases of disease. Except cervical cancer, HPV cause 85% of rectal cancer, 50% of the vulva, vagina and penis cancers, 20% of oropharyngeal cancer and 10% of larynx and esophagus cancers. In 2009, 14 000 women were diagnosed with cervical cancer in Russia. The growth in morbidity was 19% (in comparison with 1999). The most effective recognised measure for almost each infection prophylaxis is a vaccination. Two human papilloma virus vaccines are available in Russia nowadays — Gardasil and Cervarix, produced in Belgium and the Netherlands respectively. Cervarix is a bivalent vaccine based on virus-like particles (VLP) of two types. Recombinant major capsid proteins L1 HPV 16 and HPV 18 express in baculovirus expression system and self-assembled into virus-like particles (about 70 percent of cervical cancers are caused by HPV 16 and HPV 18). VLP of each strain produced in different baculovirus vectors and then combined in single drug. Gardasil is like Cervarix with few exceptions. Producing organisms are fungi S. cerevisiae in this case, and this vaccine contains low-risk HPV 6 and HPV 11 VLP. Thus, Gardasil is quadrivalent HPV-6/11/16/18 vaccine. These vaccines are very effective in averting infection of disease and don’t have significant side-effects, however they have some disadvantages. Firstly, they have a high price because of necessity of their expression in eukaryotic cells. Secondly, they are strain-specific, so vaccines are completely effective only for virus’s strains which are represented in the vaccine. Thirdly, it`s the absence of therapeutic (treatment of established infection) value of stated vaccines. According to information from literature, N-terminus of the L2 protein can induce non strain-specific neutralizing antibody that protects organism from papillomavirus challenge. E7 protein is a virus oncogene, its function is unlimited proliferation of infected cells that cause malignization in chronic course of disease. This protein is a very attractive target for therapeutic vaccines because of its necessity both for virus life cycle and sustenance of malignant phenotype in cancer cells. So, in this research the design of immunogen on the base of proteins HPV L2 and E7 is selected, vaccine on the base of which will avoid the disadvantages of Gardasil and Cervarix listed above. The stain-producer of protein on the base of cells E. coli was created. The protein was purified in denaturing reducing conditions by metal-affine chromatography and refold by sequential remove of urea and 2-mercaptoethanol.
MEASLES VIRUS IMMUNITY LEVEL STUDY IN PARTICULAR POPULATION GROUPS OF THE REPUBLIC OF GUINEA WITHIN THE FRAMEWORK OF GLOBAL MEASLES ELIMINATION PROGRAM. REPORT 1
Abstract
Measles remains one of the main reasons for child mortality in developing countries and periodically leads to the emergence of large outbreaks in different countries. This problem became especially urgent after WHO accepted the strategic plan to fight against measles. The plan has set the goal to decrease measles on a global scale. In 2010–2011 the large outbreaks of measles were registered on the African continent: in the Democratic Republic of Congo in the south of Africa, in Nigeria and in some other African countries. In the Republic of Guinea vaccination against measles is carried out singly to children aged 9 months. In 2014–2015 the increase of measles incidence was noted. Materials and methods. Using ELISA 22 blood serum samples of healthy adult Guineans aged 24–71 and 136 blood serum samples received from children and adults — the patients of hospital in the town of Kindi (Republic of Guinea) have been examined. The clinical samples were received in 2015–2016. The following test systems were used: the test systems produced by Euroimmun Medizinische Labordiagnostika AG (Germany): «Anti-Measles Virus ELISA (IGM)», «Anti-Measles Virus ELISA (IgG)»; «Avidity: Anti-Measles Virus ELISA (IgG)», and also ELISA Vector-Best IgM-measles test system (Russia). Results and discussion. Only one out of 22 examined healthy individuals hasn’t revealed IgG-antibodies to measles virus. The quantitative titre test of IgG-antibodies, and also their avidity among other 21 individuals testify experiencing measles in the recent or remote past. Having examined 116 blood serum samples of hospital patients in Kindi for IgM-measles-antibodies, the measles case with a 2.5-year-old child has been retrospectively revealed. Having examined 130 blood serum samples for IgG-antibodies to measles virus, 12.3% of seronegative to measles individuals have been revealed. All examined individuals aged 23 and older were seropositive to measles virus, and 60% of them had high antibody titres. The antibodies to measles virus were absent or were defined in low titres among 76.2% of people under 22, which can demonstrate violations of planned child vaccination due to the Ebola outbreak. In order to decrease the risk of emergence of large measles outbreaks in the areas, free from Ebola virus transmission, WHO recommends to conduct mass anti-measles vaccination campaigns.
GENETIC VARIANTS OF HEPATITIS B VIRUS IN PRIMARY DONORS IN ASTANA, KAZAKHSTAN
Abstract
The prevalence of one of the hepatotropic virus, hepatitis B virus (HBV) remains a serious global health problem. Since hepatitis B is transmitted through contact with blood or other fluids of an infected person, blood safety is one of the major public health issues in regions with high virus prevalence. Observed in recent years the trend to a shift in the prevalence of various genotypes of HBV in different geographical areas due to immigration from regions of the world with a high incidence of hepatotropic viruses, makes doctors and epidemiologists to pay close attention to the epidemiological situation in neighboring countries. The aim of our work was to study the characteristics of the genetic structure of the HBV in primary donors in Astana, Kazakhstan. A total of 30 blood plasma samples from newly diagnosed hepatitis B (HBsAg+) of Astana. HBV DNA was detected in 27 samples out of 30. Based on the phylogenetic analysis of the isolates showed that among patients examined HBV identified mainly D genotype, which is the most common genotype of HBV in Central Asia. Thus HBV subtype predominant D1 (85,2%) compared to the HBV subtype D2 (3,7%) and subtype D3 (7,4%), in a single sample was detected HBV genotypes A subtype A1. High similarities identified isolates previously described in Iran, Sudan, Mongolia, Tunisia suggest numerous independent, perhaps mutual, the importation of the virus in the country, including in the major migration waves. First detected at the territory of Kazakhstan HBV subtype A1, uncharacteristic for the region, as well as subtypes D2 and D3, which have a high similarity with the nucleotide sequences of HBV in Russia, show cases of importation of the virus from other countries. Identification of the propagation and the role of «imported» genotypes of HBV virus in circulation may be essential for regions where the prevalence of hepatotropic viruses is high, and the genome structure and the way of their distribution sufficiently studied.
NASAL MUCOUS MEMBRANE MICROFLORA IN PATIENTS WITH POLYPOUS RHINOSINUSITIS
Abstract
Nasal mucous membrane microbiocenosis Research amongst patients with polypous rhinosinusitis is conducted. Patients with polypous rhinosinusitis (PRS, n = 58) aged from 18 till 64 years and group of control (n = 156). For an microflora assessment of nasal mucous membrane during an exacerbation of a disease carried out crops of microorga nisms on nutrient differential and diagnostic agars. When studying the microflora received from nasal mucous membrane 407 cultures of microorganisms at PRS were revealed. In control group of 174 microorganisms cultures are revealed. Among isolates were established 6 genera of 9 species of bacteria at PRS against 6 genera and 8 species in group of control. Microflora quantitative structure research of nasal mucous membrane at PRS of rather control group considerable prevalence of the microorganisms belonging to the sorts Staphylococcus and Streptococcus, and also to Enterobacteriaceae was revealed. It is also revealed increase S. pneumoniae. When determining specific accessory of the microorganisms relating to the Staphylococcus genera in PRS group concerning control the increase in total number of the strains of S. aureus relating to coagulase-positive and S. haemolyticus, S. epidermidis relating to coagulase-negative staphylococcus was established. A big variety the coagulase-negative of Staphylococcus is also revealed: S. epidermidis, S. haemolyticus, S. hominis, S. cohnii, S. capitis, S. hyicius and S. xylosus. In control group of such types as S. capitis and S. hyicius it isn’t revealed. Thus at a polypous rhinosinusitis nasal mucous membrane the expressed dysbacteriosis takes place. The analysis of frequency of occurrence of the microorganisms belonging to different childbirth showed that in PRS group bacteria of the sort Streptococcus and this Nesseria, and also S. pneumoniae, S. pyogenes were most often allocated concerning control. The frequency prevalence analysis of the gene ra Staphylococcus related bacteria, allocated from nasal mucous membrane showed high detection percent as the coagulase-positive of Staphylococcus which to treat golden staphylococcus, and the coagu-lase-negative staphylococcus, such as S. epidermidis, S. haemolyticus, S. hominis, S. cohnii, S. capitis, S. hyicius and S. xylosus in PRS group concerning control. The carried-out analysis virulent and the persistent of properties of Staphylococcus revealed features of the enzymatic device defining the clinical course of a disease: staphylococcus, it is long vegetative on a mucous membrane of a nose change the properties towards increase of resistance to bactericidal influence of natural resistance that probably tells them additional selective benefits at development of inflammatory process.
SHORT COMMUNICATIONS
MICROBIOLOGICAL METHODS APPLICATION EXPERIENCE IN THE SEVERE INJURIES INFECTIOUS COMPLICATIONS
Abstract
Modern clinical medicine and surgery problems are associated with infections complications after medical care. In recent years, surgery has made substantial progress related to the new organizational approaches and medical technology specialized medical care to the wounded and injured. However, these gains are offset by a high rate of infectious complications that require finding effective measures emerging infectious complications timely diagnosis and their prevention. Clinical manifestations are often nosocomial in patients with severe injuries and are largely determined by the influence of clinical and pathogenetic risk factors. Such infectious complications require a comprehensive assessment, including microbiological testing. The main causative agents of infectious complications in surgical hospitals are S. aureus, K. pneumoniae, P. aeruginosa, Acinetobacter spp., which can cause bloodstream infections, soft tissue, respiratory and urinary tract infections, especially in debilitated and immunocompromised patients and patients in intensive care units. These micro organisms are dangerous to patients and medical staff, as they can survive for a long time in the hospital environment, as well as to spread from patient to patient in violation of isolation restrictive measures and requirements for hygiene of medical workers hands. Clinical patterns of infection associated with medical care for severe injuries are to the possibility of serial and parallel development, both in different and in the same time frame of local, visceral and generalized infection with prevalence of combined forms of patients surgical hospital with a high risk of nosocomial infection against the background of factors, diagnostic and treatment process and hospital environment, introduction of the agent. Early etiological diagnosis allows timely assign empirical causal treatment and arrange for infection control to prevent the spread of microorganisms in the hospital. The use of chromogenic (fluorogenic) environments in the study samples of clinical material at the stage of primary seeding makes it possible to obtain rapid response (18–24 h). Microbiological monitoring in the diagnosis of infectious complications in patients with severe injuries and epidemiological surveillance for infections associated with medical care can detect agents capable of becoming the leading pathogens, form stable intra and inter group associations and change the nature of the infection on persistence type superinfection and reinfection, as well as the features of the multi year and intra change frequency allocation pathogens.
OPEN ENDED RESULTS OF ACUTE DIARRHEA AGENT DETECTION TO VERIFY DIAGNOSIS IN ADULT CASES
Abstract
In 264 adult acute diarrhea cases with moderate course it was analyzed both symptoms and agents detected by different methods: in 91 cases (examined in the period of shigellosis high incidence level) — by culture and serologic (specific antibodies detection) methods to detect Shigella spp. and Salmonella spp. plus ELISA method to detect rotavirus antigen in feces; in 173 cases (examined in the period of shigellosis low incidence level) — by above mentioned methods plus PCR based method. Data obtained in the period of shigellosis high incidence level have shown that there has been no significant difference in clinical scores (including colitis frequency) between cases positive only for rotavirus antigen and those positive both for rotavirus antigen and Shigella spp. culture. That let suspect that acute diarrhea had been likely to be caused by association of rotavirus with any bacterial agent undetected by the methods used. PCR-based diagnostic method additionally used (in the period of shigellosis low incidence level) resulted in detection of Campylobacter spp. accounted for campilobacteriosis as mono infection in 20,8% cases and as mixed infection (in association with other enteropatho-gens) — in 4% cases. In cases with colitis the additional usage of PCR-based diagnostic method resulted in Salmonella spp. and Campylobacter spp. detection in every third case, Shigella spp. and agent association detection — in every fifth case. The target analysis of enteropathogens detected in 15 cases positive for rotavirus (examined in the period of shigellosis low incidence level) has shown that in 6 of them there has been detected association of rotavirus with other agents predominantly bacterial ones (in 5 of 6 cases). So, the PCR method might be quite useful to broaden the spectrum of detected enteropathogens in adult acute diarrhea cases especially in those with colitis syndrome available.
THE INFLUENCE OF PATHOGENETIC THERAPY ON THE LEVER OF CYTOKINES IN PATIENTS WITH ACUTE BRUCELLOSIS
Abstract
The purpose of the study was to determine the level of proinflammatory cytokines: IL-12, IL-8 and IFNγ, neopterin and lipopolysaccharide-binding protein in the serum of patients with acute brucellosis before and after antibiotic therapy. The clinical data from 32 patients with laboratory-confirmed diagnosis — “acute brucellosis” admitted to the diagnosis, treatment and examination of occupational diseases brucellosis GBUZ SC “City Clinical Hospital No. 2”, the city of Stavropol were used in the study. The concentrations IL-12, IL-8, IFNγ cytokines and acute-phase proteins in serum was determined by ELISA. In the acute phase of brucellosis infection (before treatment) had high levels of pro-inflammatory cytokines IL-8 and IFNγ, but despite holding a course of antibiotic treatment in the serum of patients with preserved high levels of IL-8, indicative of active inflammation in the absence of clinical manifestations. IL-12 level, a key cytokine in the initiation of lymphocyte-dependent immune response was lower than in the control group. Evaluation of the cytokine status (IL-8, IL-12, IL-18) and proteins of acute inflammation phase (neopterin and lipopolysaccharide-binding protein) will provide valuable information for monitoring the effect of pharmacotherapy of acute brucellosis. Indicators of lipopolysaccharide-binding protein and neopterin in the serum of patients with brucellosis should be considered as a marker of inflammatory activity and as a predictor of outcome of acute brucellosis.
METHODS
COMPARATIVE EVALUATION OF CULTURE MEDIA FOR PATHOGEN ISOLATION OF PURULENT BACTERIAL MENINGITIS
Abstract
The State Research Center for Applied Microbiology and Biotechnology has designed two nutrient media — chocolate agar and PBM-agar to isolate pathogens of purulent bacterial meningitis (PBM). In our previous research using collected microbial strains the media were shown to be highly susceptible and to provide the growth of Neisseria meningiti-dis, Streptococcus pneumoniae and Haemophilus influenzae strains, when inoculated with microbial suspensions containing single cells. When isolating Haemophilus influenzae, meningococci, and pneumococci the use of selective additives in both media assures selective isolation of required microorganisms, inhibiting contaminants. The objective of this research was to assess the media in bacteriological tests of clinical samples collected from the upper and lower respiratory tract in humans. The bacteriological plating of throat smear specimens (n = 90) from children and adults at the age of 0 to 66 with disorder of the upper respiratory tract on chocolate agar, PBM-agar and on a control medium in the absence of selective additives resulted in the equal amount of microbial cultures isolated. Of 154 isolated cultures 2, 23 and 9 were attributed to Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae, respectively. The plating of throat smears (n = 10) from healthy people at the age of 30 to 55 on the analyzable and control media in the presence of additives allowed us to selectively isolate Haemophilus influenzae and Streptococcus pneumoniae cultures without a quantitative loss, with contaminants inhibited. By their growth characteristics chocolate agar and PBM-agar were highly competitive with reference media being used in clinical practice for isolating main causative agents of purulent bacterial meningitis.
RAPID URINE SCREENING FOR BACTERIURIA IN CHILDREN USING MICROBIOLOGY ANALYZER, COMBINING PHOTOMETRIC AND COHERENT FLUCTUATION NEPHELOMETRIC METHODS
Abstract
One of the most widespread microbiological analyses in clinical practice is urine culture, and up to 80% of urine samples turn out to be negative. In this study we demonstrate applicability of coherent fluctuating nephelometry (CFN) method for rapid urine screening and negative samples identification for the purpose of reducing the workload of microbiological laboratory. 205 urine samples were tested by conventional culture method (CCM) and using CFN-analyzer. The agreement between CCM and CFN was 87.8%. Compared to CCM, CFN demonstrated sensitivity — 94.5%, specificity — 85.3%, negative predictive value — 97.7%, positive predictive value — 70.3%. In this study CFN-analyzer allowed to identify 85.3% of negative urine samples (63.9% of all tested samples) within 4 hours, and 94.5% of positive samples were retained for later CCM. Moreover none of samples with count ≥ 104 CFU/ml was omitted.