scholarly journals Establishing and evaluation of a polymerase chain reaction for the detection of Echinococcus multilocularis in human tissue

2021 ◽  
Vol 15 (2) ◽  
pp. e0009155 ◽  
Author(s):  
Johannes Grimm ◽  
Julian Krickl ◽  
Annika Beck ◽  
Juliane Nell ◽  
Monika Bergmann ◽  
...  

Background Alveolar echinococcosis (AE) is caused by metacestode larva of the tapeworm Echinococcus multilocularis. AE diagnostics currently rely on imaging techniques supported by serology, but unequivocal detection of AE is difficult. Although polymerase chain reaction (PCR)-based methods to detect tapeworm DNA in biopsies have been suggested for several species, no validated protocol adhering to accepted guidelines has so far been presented for AE diagnostics. We herein established a PCR protocol for metacestode biopsies and technically evaluated the method using isolated parasite DNA and cells, biopsies of clinically relevant material, and formalin fixed paraffin-embedded (FFPE) human tissue blocks. We compared the results with an immunochemical (IHC) approach using the monoclonal antibody Em2G11 specific for the antigen Em2 of E. mulitlocularis. Methodology/Principal findings Based on tapeworm 12S rDNA sequences we established and validated a PCR protocol for robust detection of as little as 50 parasite cells per specimen and report 127 cases of positive identification of Echinococcus species in samples from humans and animals. For further validation, we analyzed 45 liver, heart, brain, and soft tissue samples as well as cytological probes of aspirates of FFPE-material from 18 patients with clinically confirmed AE. Of each patient we analyzed (i) fully viable lesions with laminated layer; (ii) tissue with mAbEm2G11-positive small particles of E. multilocularis (spems); (iii) mAbEm2G11-negative tissue adjacent to the main lesion; and (iv) lymph node tissue with mAbEm2G11-positive spems. To identify the areas for the PCR-based approach, we performed IHC-staining with the monoclonal antibody Em2G11. Micro-dissected tissue of these areas was then used for PCR-analysis. 9 of 15 analyzed samples with viable E. multilocularis lesions with laminated layer were positive by PCR. Of this group, all samples preserved for less than 6 years (6/6) were tested positive. 11 of 15 samples of spems and 7 of 9 samples of the control group mAbEm2G11-negative tissue were negative by PCR. We further show that all probes from lymph nodes with spems are PCR negative. Conclusions/Significance We present a sensitive PCR method for the detection of E. multilocularis in human tissue, particularly in fresh biopsy material and tissue blocks stored for less than 5 years. While the diagnostic sensitivity of material containing only spems was higher using IHC, PCR detection was possible in IHC negative liver tissue and in patients with negative serology. Our results support the view that spems do not contain parasitic DNA or viable cells of the parasite. spems thus most probably do not directly contribute to metastasis formation during AE.

2009 ◽  
Vol 27 (36) ◽  
pp. 6094-6100 ◽  
Author(s):  
Lindsey Goff ◽  
Karin Summers ◽  
Sameena Iqbal ◽  
Jens Kuhlmann ◽  
Michael Kunz ◽  
...  

Purpose The randomized First-Line Indolent Trial (FIT) was conducted in patients with advanced follicular lymphoma (FL), to evaluate the safety and efficacy of yttrium-90 (90Y) ibritumomab tiuxetan given as consolidation of complete or partial remission. This study of minimal residual disease was undertaken in parallel, to determine the rate of conversion from bcl-2 polymerase chain reaction (PCR) –detectable to –undetectable status and the corresponding effect on progression-free survival (PFS). Patients and Methods Blood samples from 414 patients (90Y-ibritumomab, n = 208; control, n = 206) were evaluated using real-time quantitative polymerase chain reaction (RQ-PCR); 186 were found to have the bcl-2 rearrangement and were thus eligible for inclusion in the RQ-PCR analysis. Results Overall, 90% of treated patients converted from bcl-2 PCR–detectable to –undetectable disease status, compared with 36% in the control group. Treatment significantly prolonged median PFS in patients converting to bcl-2 PCR-undetectable status (40.8 v 24.0 months in the control group; P < .01, hazard ratio [HR], 0.399). In patients who had bcl-2 PCR-detectable disease at random assignment, treatment significantly prolonged median PFS (38.4 v 8.2 months in the control group; P < .01, HR, 0.293). Conclusion Eradication of PCR-detectable disease occurred more frequently after treatment with 90Y-ibritumomab tiuxetan and was associated with prolongation of PFS.


2006 ◽  
Vol 43 (2) ◽  
pp. 76-80 ◽  
Author(s):  
M. Miterpáková ◽  
D. Antolová ◽  
Z. Ševčíková ◽  
M. Stanko ◽  
A. Dinkel ◽  
...  

AbstractInfection with the larval stage of Echinococcus multilocularis was diagnosed in musk rat (Ondatra zibethicus) in the Slovak Republic. At necropsy, massively enlarged liver with numbers of abscess-like lesions up to 1.5 cm in diameter was found. Histological examination shoved the presence of typical multivesicular cysts with multiple protoscoleces and typical laminated layer. Polymerase chain reaction confirmed the diagnosis. According to our knowledge, this is the first documentation of Echinococcus multilocularis in naturally infected rodent in territory of the Slovak Republic.


LWT ◽  
2015 ◽  
Vol 63 (1) ◽  
pp. 714-719 ◽  
Author(s):  
Sahilah Abd Mutalib ◽  
Nursheila Mustafa Muin ◽  
Aminah Abdullah ◽  
Osman Hassan ◽  
Wan Aida Wan Mustapha ◽  
...  

Author(s):  
Jun-Hyung Lim ◽  
Sang Hwan Nam ◽  
Jongwoo Kim ◽  
Nam Hoon Kim ◽  
Gun-Soo Park ◽  
...  

Abstract In this study, a three-stage bioaerosol sampler with a sampling flow rate of 170 L/min was designed and fabricated for sampling the bioaerosols released during human breathing and coughing, and its performance was evaluated. The sampler was constructed using a cyclone separator with a cutoff size of 2.5 µm as a preseparator, a multi-nozzle virtual impactor with a cutoff size of 0.34 µm as an aerosol concentrator, and a BioSampler, which is a commercial product, for collecting bioaerosols in a collection fluid. The collection efficiency of the sampler was evaluated through simulations and experiments. Only particles with sizes of 0.1-4 µm were selectively collected in the collection fluid. Bacteriophage bioaerosols were sampled using the developed sampler and ACD-200 Bobcat sampler, which is a commercial product. The amounts of collected bacteriophages were compared using the polymerase chain reaction (PCR) technique. The sampling performance of the developed sampler was similar to that of the ACD-200 Bobcat sampler. Moreover, the developed sampler showed its ability to sample bioaerosols of a specific size-range and collect them directly in a collection fluid for the PCR analysis. Therefore, the developed sampler is expected to be useful for indoor environmental monitoring by effectively sampling the bioaerosols released indoors during human breathing and coughing.


2018 ◽  
Vol 48 (6) ◽  
Author(s):  
Marcelo Marques da Silveira ◽  
Stéfhano Luis Cândido ◽  
Karin Rinaldi dos Santos ◽  
Maerle Oliveira Maia ◽  
Roberto Lopes de Souza ◽  
...  

ABSTRACT: Sepsis is characterized by the presence of organ dysfunction secondary to the dysregulated systemic inflammatory response associated with an infection, and has high mortality rates. Traditional diagnostic techniques based on non-microbiological isolation are time-consuming and may delay treatment. Thus, this study aimed to compare bacterial and fungal broad-range polymerase chain reaction (PCR) and blood culture for diagnosis of sepsis in dogs. Blood samples from 88 dogs with suspected sepsis were analyzed by blood culture, and PCR to detect bacterial and fungal DNA. On blood culture, 20 (22.7%) samples tested positive for bacterial isolates; however, none tested positive for fungi. Through PCR analysis, bacterial DNA was detected in 46 (52.3%) animals, whereas fungal DNA was present in one (1.1%) sample. Our results showed that PCR-based testing has important diagnostic value for canine blood infections because it has a shorter turnaround time and higher sensitivity than traditional blood culture.


2015 ◽  
Vol 53 (4) ◽  
pp. 345-352
Author(s):  
Y.B. Zheng ◽  
Y. Zhao ◽  
L.Y. Yue ◽  
P. Lin ◽  
Y.F. Liu ◽  
...  

Background: DNA methylation has been implicated in the pathogenesis of allergy and atopy. This study aimed to identify whether DNA methylation also plays an important role in the pathogenesis of nasal polyps (NP). Methodology: NP tissues were obtained from 32 patients with chronic rhinosinusitis with bilateral NP. Biopsies of inferior turbinate mucosa (ITM) were taken from 18 patients who underwent rhinoseptoplasty (control group). The methylated genes, which were detected by DNA methylation microarray, were validated by methylation-specific polymerase chain reaction, bisulphite sequencing, real-time polymerase chain reaction and immunohistochemistry. Results: DNA methylation microarray identified 8,008 CpG islands in 2,848 genes. One hundred and ninety-eight genes were found to have a methylated signal in the promoter region in NP samples compared with ITM samples. The four top genes that changed, COL18A1, EP300, GNAS and SMURF1, were selected for further study. The methylation frequency of COL18A1 was significantly higher in NP samples than in ITM samples. Conclusions: DNA methylation might play an important role in the pathogenesis of NP. Promoter methylation of COL18A1 was found to be significantly increased in NP tissues, further studies are necessary to confirm the significance of these epigenetic factors in the mechanisms underlying the development or persistence of NP.


2021 ◽  
Vol 6 (2) ◽  
pp. 115-124
Author(s):  
V. Zyuzin ◽  
◽  
O. Tuzova ◽  
U. Frenkel ◽  
Muntian L. ◽  
...  

The purpose of the study. The article covers the issues of genotyping of listeria by polymerase chain reaction (PCR) and its epidemiological significance. It is known that molecular genetic methods allow to detect specific microbial pathogens, virulence markers, antimicrobial resistance genes faster and with greater sensitivity than traditional culture methods. Therefore, the development of detection methods and genotyping by polymerase chain reaction (PCR) is relevant. Materials and methods. For the detection and genotyping of Listeria, the technology of DNA chips is becoming increasingly important, which can significantly expand the possibilities of molecular detection. Chip technology can be used to simultaneously identify a whole range of pathogenic microorganisms, to determine genetic virulence markers, the relationship to antibiotics, subtyping, as well as to determine the quality of microorganisms in samples. A simplified version of DNA chip technology is multiplex (numerical) PCR, which is used to detect and genotype listeria. Studies have shown that to detect Listeria spp. using a polymerase chain reaction, it is advisable to use the gene iap (invasive associated protein), known for 6 species of listeria, which encodes a protein P 60 that is common to all species of listeria, including L.murrayi. Computer analysis revealed areas with 100% homology, from which primers were selected for PCR detection of all types of listeria. Areas of genomes characterized by 100% homology were selected for further analysis and labeling of primer sets. The sequences of the constructed primers List 1 and List 2 allowed to identify 6 species of Listeria (L. monocytogenes, L. innocua, L. ivanovii, L. grayi, L. seeligeri, L. welshimeri). Increasing the length of the primer leads to the increasing of specificity of PCR analysis. The greater the length of the primer, the smaller the specific gravity of one error of the unpaired nucleotide. The degree of primer homology is a key parameter that indicates the "quality" of a set of primers. Results and discussion. It is established that a significant disadvantage of the vast majority diagnosed using PCR test systems is the lack of internal control of amplification. The negative result of PCR analysis may be due to the absence in the clinical material of a fragment of the Listeria genome, and the fact that the PCR product was not synthesized for other reasons. They may be as the following ones: operator errors, erroneously determined reaction mixture concentrations and PCR temperature parameters. False-negative results can also be caused by factors that inhibit thermostable DNA polymerase. In its turn, such inhibition of the enzyme responsible for amplification is caused by a very large amount of DNA - template, pre-treatment of clinical samples. It has been shown that 80% of clinical specimens contain a substance that inhibits DNA polymerase. Therefore, it is necessary to use internal control, the positive result of the reaction of which indicates the successful amplification, that is the absence of false positive results. Conclusion. There are several reasons why the accuracy of PCR analysis does not reach 100%. Accuracy depends on the technology (variety) of PCR - the method used (ordinary or fluorescent), detection of amplicons, PCR homogeneous or nested, nested in one test tube or in two test tubes, as well as the level of quality of the survey (primarily on the technical parameters of the amplifier). The test systems used can be used for PCR detection and are recommended as standard primer sets for the detection and cross-species testing of listeria, which is important for the timely implementation of appropriate anti-epidemic measures in listeriosis


2019 ◽  
Vol 62 (1) ◽  
pp. 125-133 ◽  
Author(s):  
Mengli Zhao ◽  
Huitong Zhou ◽  
Jon G. H. Hickford ◽  
Hua Gong ◽  
Jiqing Wang ◽  
...  

Abstract. Keratin-associated proteins (KAPs) are a structural component of cashmere fibre, and variation in some KAP genes (KRTAPs) has been associated with a number of caprine fibre traits. In this study, we report the identification of KRTAP15-1 in goats. Sequence variation in the gene was detected using the polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) technique in 250 Longdong goats, and six variants (named A to F) containing eight single nucleotide polymorphisms (SNPs) were identified. Five of the SNPs were non-synonymous and would lead to putative amino acid changes. Reverse-transcription polymerase chain reaction (RT-PCR) analysis revealed that KRTAP15-1 was expressed in secondary hair follicles but not in heart tissue, liver tissue, lung tissue, kidney tissue or the longissimus dorsi muscle. Despite being rich in cysteine, the caprine KAP15-1 protein possesses a high content of serine and moderate content of glycine and phenylalanine. Association analyses revealed that KRTAP15-1 variant A was associated with decreased mean fibre diameter (MFD), and this effect appeared to be dominant; while variant C was found to be associated with increased MFD, the effect being recessive. The findings suggest that caprine KRTAP15-1 is highly polymorphic and that variation in this gene affects cashmere MFD.


Sign in / Sign up

Export Citation Format

Share Document