Towards the establishment of a consensus real-time qPCR to monitor Trypanosoma cruzi parasitemia in patients with chronic Chagas disease cardiomyopathy: A substudy from the BENEFIT trial
Establishment of a consensus real-time qPCR to compare Trypanosoma cruzi burden in blood of chronic cardiomyopathy Chagas disease patients from the BENEFIT clinical trial. [Display omitted] ► We established a SYBR Green real-time qPCR assay to quantify T. cruzi load in blood. ► Chronic Chagas cardio...
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| creator | Moreira, Otacilio C. Ramírez, Juan David Velázquez, Elsa Melo, Myllena F. A. Dias Lima-Ferreira, Carolina Guhl, Felipe Sosa-Estani, Sergio Marin-Neto, Jose Antonio Morillo, Carlos A. Britto, Constança |
| description | Establishment of a consensus real-time qPCR to compare Trypanosoma cruzi burden in blood of chronic cardiomyopathy Chagas disease patients from the BENEFIT clinical trial. [Display omitted]
► We established a SYBR Green real-time qPCR assay to quantify T. cruzi load in blood. ► Chronic Chagas cardiomyopathy patients from the BENEFIT trial were evaluated. ► The median parasitic load found in Brazilian patients was 0.1 parasite equivalents/mL. ► Chronic Chagas disease patients from Colombia and Argentina yielded parasitemia values roughly 20 times higher than patients from Brazil. ► qPCR is useful to detect and quantify low parasite burden in chronic Chagas disease.
Quantitative real-time PCR (qPCR) is an accurate method to quantify Trypanosoma cruzi DNA and can be used to follow-up parasitemia in Chagas disease (CD) patients undergoing chemotherapy. The Benznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) study is an international, multicenter, randomized, double-blinded and placebo-controlled clinical trial to evaluate the efficacy of benznidazole (BZ) treatment in patients with chronic Chagas cardiomyopathy (CCC). One important question to be addressed concerns the effectiveness of BZ in reducing overall parasite load in CCC patients, even in the absence of parasitological cure. This report describes the evaluation of multiple procedures for DNA extraction and qPCR-based protocols aiming to establish a standardized methodology for the absolute quantification of T. cruzi DNA in Guanidine-EDTA blood (GEB) samples. A panel of five primer sets directed to the T. cruzi nuclear satellite DNA repeats (Sat-DNA) and to the minicircle DNA conserved regions (kDNA) was compared in either SYBR Green or TaqMan systems. Standard curve parameters such as, amplification efficiency, coefficient of determination and intercept were evaluated, as well as different procedures to generate standard samples containing pre-established T. cruzi DNA concentration. Initially, each primer set was assayed in a SYBR Green qPCR to estimate parasite load in GEB samples from chronic Chagas disease patients. The results achieved from Bayesian transmutability analysis elected the primer sets Cruzi1/Cruzi2 (p=0.0031) and Diaz7/Diaz8 (p=0.0023) coupled to the QIAamp DNA Kit extraction protocol (silica gel column), as the most suitable for monitoring parasitemia in these patients. Comparison between the parasite burden of 150 GEB samples of BENEFIT patients from Argentina, Brazil |
| doi_str_mv | 10.1016/j.actatropica.2012.08.020 |
| format | Article |
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► We established a SYBR Green real-time qPCR assay to quantify T. cruzi load in blood. ► Chronic Chagas cardiomyopathy patients from the BENEFIT trial were evaluated. ► The median parasitic load found in Brazilian patients was 0.1 parasite equivalents/mL. ► Chronic Chagas disease patients from Colombia and Argentina yielded parasitemia values roughly 20 times higher than patients from Brazil. ► qPCR is useful to detect and quantify low parasite burden in chronic Chagas disease.
Quantitative real-time PCR (qPCR) is an accurate method to quantify Trypanosoma cruzi DNA and can be used to follow-up parasitemia in Chagas disease (CD) patients undergoing chemotherapy. The Benznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) study is an international, multicenter, randomized, double-blinded and placebo-controlled clinical trial to evaluate the efficacy of benznidazole (BZ) treatment in patients with chronic Chagas cardiomyopathy (CCC). One important question to be addressed concerns the effectiveness of BZ in reducing overall parasite load in CCC patients, even in the absence of parasitological cure. This report describes the evaluation of multiple procedures for DNA extraction and qPCR-based protocols aiming to establish a standardized methodology for the absolute quantification of T. cruzi DNA in Guanidine-EDTA blood (GEB) samples. A panel of five primer sets directed to the T. cruzi nuclear satellite DNA repeats (Sat-DNA) and to the minicircle DNA conserved regions (kDNA) was compared in either SYBR Green or TaqMan systems. Standard curve parameters such as, amplification efficiency, coefficient of determination and intercept were evaluated, as well as different procedures to generate standard samples containing pre-established T. cruzi DNA concentration. Initially, each primer set was assayed in a SYBR Green qPCR to estimate parasite load in GEB samples from chronic Chagas disease patients. The results achieved from Bayesian transmutability analysis elected the primer sets Cruzi1/Cruzi2 (p=0.0031) and Diaz7/Diaz8 (p=0.0023) coupled to the QIAamp DNA Kit extraction protocol (silica gel column), as the most suitable for monitoring parasitemia in these patients. Comparison between the parasite burden of 150 GEB samples of BENEFIT patients from Argentina, Brazil and Colombia, prior to drug/placebo administration, was performed using Cruzi1/Cruzi2 primers in a SYBR Green approach. The median parasitemia found in patients from Argentina and Colombia (1.93 and 2.31 parasite equivalents/mL, respectively) was around 20 times higher than the one estimated for the Brazilian patients (0.1 parasite equivalents/mL). This difference could be in part due to the complexity of T. cruzi genetic diversity, which is a factor possibly implicated in different clinical presentations of the disease and/or influencing parasitemia levels in infected individuals from different regions of Latin America. The results of SYBR Green qPCR assays herein presented prove this methodology to be more cost efficient than the alternative use of internal fluorogenic probes. In addition, its sensitivity and reproducibility are shown to be adequate to detect low parasitemia burden in patients with chronic Chagas disease.</description><identifier>ISSN: 0001-706X</identifier><identifier>EISSN: 1873-6254</identifier><identifier>DOI: 10.1016/j.actatropica.2012.08.020</identifier><identifier>PMID: 22982466</identifier><language>eng</language><publisher>Netherlands: Elsevier B.V</publisher><subject>Antiprotozoal Agents - administration & dosage ; Argentina ; BENEFIT ; blood ; Brazil ; Cardiac chronic Chagas disease ; cardiomyopathy ; Chagas Cardiomyopathy - drug therapy ; Chagas Cardiomyopathy - parasitology ; Chagas disease ; chemotherapy ; clinical trials ; Colombia ; DNA primers ; DNA, Protozoan - genetics ; DNA, Protozoan - isolation & purification ; Double-Blind Method ; Drug Monitoring - methods ; Drug Monitoring - standards ; genetic variation ; Humans ; kinetoplast DNA ; Molecular diagnosis ; Molecular Diagnostic Techniques - methods ; Molecular Diagnostic Techniques - standards ; monitoring ; Nitroimidazoles - administration & dosage ; parasite load ; Parasite Load - methods ; Parasite Load - standards ; parasitemia ; Parasitemia - drug therapy ; Parasitemia - parasitology ; parasites ; Parasitology - methods ; Parasitology - standards ; patients ; Placebos - administration & dosage ; quantitative polymerase chain reaction ; Randomized Controlled Trials as Topic ; Real-time PCR ; Real-Time Polymerase Chain Reaction - methods ; Real-Time Polymerase Chain Reaction - standards ; Reproducibility of Results ; satellite DNA ; Sensitivity and Specificity ; silica gel ; Specimen Handling - methods ; Trypanosoma cruzi ; Trypanosoma cruzi - isolation & purification</subject><ispartof>Acta tropica, 2013-01, Vol.125 (1), p.23-31</ispartof><rights>2012 Elsevier B.V.</rights><rights>Copyright © 2012 Elsevier B.V. All rights reserved.</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c485t-15547e4aa38deb955a9cd316966ef5f3f4cfb82770524dc860c6777d482516ce3</citedby><cites>FETCH-LOGICAL-c485t-15547e4aa38deb955a9cd316966ef5f3f4cfb82770524dc860c6777d482516ce3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://www.sciencedirect.com/science/article/pii/S0001706X12003063$$EHTML$$P50$$Gelsevier$$Hfree_for_read</linktohtml><link.rule.ids>314,776,780,3537,4010,27900,27901,27902,65306</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/22982466$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Moreira, Otacilio C.</creatorcontrib><creatorcontrib>Ramírez, Juan David</creatorcontrib><creatorcontrib>Velázquez, Elsa</creatorcontrib><creatorcontrib>Melo, Myllena F. A. Dias</creatorcontrib><creatorcontrib>Lima-Ferreira, Carolina</creatorcontrib><creatorcontrib>Guhl, Felipe</creatorcontrib><creatorcontrib>Sosa-Estani, Sergio</creatorcontrib><creatorcontrib>Marin-Neto, Jose Antonio</creatorcontrib><creatorcontrib>Morillo, Carlos A.</creatorcontrib><creatorcontrib>Britto, Constança</creatorcontrib><title>Towards the establishment of a consensus real-time qPCR to monitor Trypanosoma cruzi parasitemia in patients with chronic Chagas disease cardiomyopathy: A substudy from the BENEFIT trial</title><title>Acta tropica</title><addtitle>Acta Trop</addtitle><description>Establishment of a consensus real-time qPCR to compare Trypanosoma cruzi burden in blood of chronic cardiomyopathy Chagas disease patients from the BENEFIT clinical trial. [Display omitted]
► We established a SYBR Green real-time qPCR assay to quantify T. cruzi load in blood. ► Chronic Chagas cardiomyopathy patients from the BENEFIT trial were evaluated. ► The median parasitic load found in Brazilian patients was 0.1 parasite equivalents/mL. ► Chronic Chagas disease patients from Colombia and Argentina yielded parasitemia values roughly 20 times higher than patients from Brazil. ► qPCR is useful to detect and quantify low parasite burden in chronic Chagas disease.
Quantitative real-time PCR (qPCR) is an accurate method to quantify Trypanosoma cruzi DNA and can be used to follow-up parasitemia in Chagas disease (CD) patients undergoing chemotherapy. The Benznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) study is an international, multicenter, randomized, double-blinded and placebo-controlled clinical trial to evaluate the efficacy of benznidazole (BZ) treatment in patients with chronic Chagas cardiomyopathy (CCC). One important question to be addressed concerns the effectiveness of BZ in reducing overall parasite load in CCC patients, even in the absence of parasitological cure. This report describes the evaluation of multiple procedures for DNA extraction and qPCR-based protocols aiming to establish a standardized methodology for the absolute quantification of T. cruzi DNA in Guanidine-EDTA blood (GEB) samples. A panel of five primer sets directed to the T. cruzi nuclear satellite DNA repeats (Sat-DNA) and to the minicircle DNA conserved regions (kDNA) was compared in either SYBR Green or TaqMan systems. Standard curve parameters such as, amplification efficiency, coefficient of determination and intercept were evaluated, as well as different procedures to generate standard samples containing pre-established T. cruzi DNA concentration. Initially, each primer set was assayed in a SYBR Green qPCR to estimate parasite load in GEB samples from chronic Chagas disease patients. The results achieved from Bayesian transmutability analysis elected the primer sets Cruzi1/Cruzi2 (p=0.0031) and Diaz7/Diaz8 (p=0.0023) coupled to the QIAamp DNA Kit extraction protocol (silica gel column), as the most suitable for monitoring parasitemia in these patients. Comparison between the parasite burden of 150 GEB samples of BENEFIT patients from Argentina, Brazil and Colombia, prior to drug/placebo administration, was performed using Cruzi1/Cruzi2 primers in a SYBR Green approach. The median parasitemia found in patients from Argentina and Colombia (1.93 and 2.31 parasite equivalents/mL, respectively) was around 20 times higher than the one estimated for the Brazilian patients (0.1 parasite equivalents/mL). This difference could be in part due to the complexity of T. cruzi genetic diversity, which is a factor possibly implicated in different clinical presentations of the disease and/or influencing parasitemia levels in infected individuals from different regions of Latin America. The results of SYBR Green qPCR assays herein presented prove this methodology to be more cost efficient than the alternative use of internal fluorogenic probes. In addition, its sensitivity and reproducibility are shown to be adequate to detect low parasitemia burden in patients with chronic Chagas disease.</description><subject>Antiprotozoal Agents - administration & dosage</subject><subject>Argentina</subject><subject>BENEFIT</subject><subject>blood</subject><subject>Brazil</subject><subject>Cardiac chronic Chagas disease</subject><subject>cardiomyopathy</subject><subject>Chagas Cardiomyopathy - drug therapy</subject><subject>Chagas Cardiomyopathy - parasitology</subject><subject>Chagas disease</subject><subject>chemotherapy</subject><subject>clinical trials</subject><subject>Colombia</subject><subject>DNA primers</subject><subject>DNA, Protozoan - genetics</subject><subject>DNA, Protozoan - isolation & purification</subject><subject>Double-Blind Method</subject><subject>Drug Monitoring - methods</subject><subject>Drug Monitoring - standards</subject><subject>genetic variation</subject><subject>Humans</subject><subject>kinetoplast DNA</subject><subject>Molecular diagnosis</subject><subject>Molecular Diagnostic Techniques - methods</subject><subject>Molecular Diagnostic Techniques - standards</subject><subject>monitoring</subject><subject>Nitroimidazoles - administration & dosage</subject><subject>parasite load</subject><subject>Parasite Load - methods</subject><subject>Parasite Load - standards</subject><subject>parasitemia</subject><subject>Parasitemia - drug therapy</subject><subject>Parasitemia - parasitology</subject><subject>parasites</subject><subject>Parasitology - methods</subject><subject>Parasitology - standards</subject><subject>patients</subject><subject>Placebos - administration & dosage</subject><subject>quantitative polymerase chain reaction</subject><subject>Randomized Controlled Trials as Topic</subject><subject>Real-time PCR</subject><subject>Real-Time Polymerase Chain Reaction - methods</subject><subject>Real-Time Polymerase Chain Reaction - standards</subject><subject>Reproducibility of Results</subject><subject>satellite DNA</subject><subject>Sensitivity and Specificity</subject><subject>silica gel</subject><subject>Specimen Handling - methods</subject><subject>Trypanosoma cruzi</subject><subject>Trypanosoma cruzi - isolation & purification</subject><issn>0001-706X</issn><issn>1873-6254</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2013</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNqNks1u1DAUhSMEokPhFcDs2GSwnfhn2JVoCpUqQDCV2Fl3HKfxKImnvg7V8Gg8HS5TEDtYWVf6zvXRObcoXjK6ZJTJ17sl2AQphr23sOSU8SXVS8rpg2LBtKpKyUX9sFhQSlmpqPx6UjxB3OWJK8EfFyecrzSvpVwUPzbhFmKLJPWOOEywHTz2o5sSCR0BYsOEbsIZSXQwlMmPjtx8aj6TFMgYJp9CJJt42MMUMIyZj_N3T_YQAX1yowfipzwmnzciufWpJ7aPWWhJ08M1IGk9OkBHbLbhw3gIme4Pb8gZwXmLaW4PpIth_GXw7frD-vxiQ1L0MDwtHnUwoHt2_54WV-frTfO-vPz47qI5uyxtrUUqmRC1cjVApVu3XQkBK9tWTK6kdJ3oqq623VZzpajgdWu1pFYqpdpac8GkddVp8eq4dx_DzZwzMqNH64YBJhdmNDlUrpiupPo3ygRTlNW0zujqiNoYEKPrzD76EeLBMGruWjY781fL5q5lQ7XJLWft8_tv5u3o2j_K37Vm4MUR6CAYuI4ezdWXvEHki9BCCpGJ5ki4nNw376JBmzuyrvXR2WTa4P_DyE_kZ8tP</recordid><startdate>201301</startdate><enddate>201301</enddate><creator>Moreira, Otacilio C.</creator><creator>Ramírez, Juan David</creator><creator>Velázquez, Elsa</creator><creator>Melo, Myllena F. A. Dias</creator><creator>Lima-Ferreira, Carolina</creator><creator>Guhl, Felipe</creator><creator>Sosa-Estani, Sergio</creator><creator>Marin-Neto, Jose Antonio</creator><creator>Morillo, Carlos A.</creator><creator>Britto, Constança</creator><general>Elsevier B.V</general><scope>6I.</scope><scope>AAFTH</scope><scope>FBQ</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7X8</scope><scope>C1K</scope><scope>F1W</scope><scope>H95</scope><scope>H97</scope><scope>L.G</scope><scope>M7N</scope></search><sort><creationdate>201301</creationdate><title>Towards the establishment of a consensus real-time qPCR to monitor Trypanosoma cruzi parasitemia in patients with chronic Chagas disease cardiomyopathy: A substudy from the BENEFIT trial</title><author>Moreira, Otacilio C. ; Ramírez, Juan David ; Velázquez, Elsa ; Melo, Myllena F. A. 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Dias</creatorcontrib><creatorcontrib>Lima-Ferreira, Carolina</creatorcontrib><creatorcontrib>Guhl, Felipe</creatorcontrib><creatorcontrib>Sosa-Estani, Sergio</creatorcontrib><creatorcontrib>Marin-Neto, Jose Antonio</creatorcontrib><creatorcontrib>Morillo, Carlos A.</creatorcontrib><creatorcontrib>Britto, Constança</creatorcontrib><collection>ScienceDirect Open Access Titles</collection><collection>Elsevier:ScienceDirect:Open Access</collection><collection>AGRIS</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>MEDLINE - Academic</collection><collection>Environmental Sciences and Pollution Management</collection><collection>ASFA: Aquatic Sciences and Fisheries Abstracts</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) 1: Biological Sciences & Living Resources</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) 3: Aquatic Pollution & Environmental Quality</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) Professional</collection><collection>Algology Mycology and Protozoology Abstracts (Microbiology C)</collection><jtitle>Acta tropica</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Moreira, Otacilio C.</au><au>Ramírez, Juan David</au><au>Velázquez, Elsa</au><au>Melo, Myllena F. A. Dias</au><au>Lima-Ferreira, Carolina</au><au>Guhl, Felipe</au><au>Sosa-Estani, Sergio</au><au>Marin-Neto, Jose Antonio</au><au>Morillo, Carlos A.</au><au>Britto, Constança</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Towards the establishment of a consensus real-time qPCR to monitor Trypanosoma cruzi parasitemia in patients with chronic Chagas disease cardiomyopathy: A substudy from the BENEFIT trial</atitle><jtitle>Acta tropica</jtitle><addtitle>Acta Trop</addtitle><date>2013-01</date><risdate>2013</risdate><volume>125</volume><issue>1</issue><spage>23</spage><epage>31</epage><pages>23-31</pages><issn>0001-706X</issn><eissn>1873-6254</eissn><abstract>Establishment of a consensus real-time qPCR to compare Trypanosoma cruzi burden in blood of chronic cardiomyopathy Chagas disease patients from the BENEFIT clinical trial. [Display omitted]
► We established a SYBR Green real-time qPCR assay to quantify T. cruzi load in blood. ► Chronic Chagas cardiomyopathy patients from the BENEFIT trial were evaluated. ► The median parasitic load found in Brazilian patients was 0.1 parasite equivalents/mL. ► Chronic Chagas disease patients from Colombia and Argentina yielded parasitemia values roughly 20 times higher than patients from Brazil. ► qPCR is useful to detect and quantify low parasite burden in chronic Chagas disease.
Quantitative real-time PCR (qPCR) is an accurate method to quantify Trypanosoma cruzi DNA and can be used to follow-up parasitemia in Chagas disease (CD) patients undergoing chemotherapy. The Benznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) study is an international, multicenter, randomized, double-blinded and placebo-controlled clinical trial to evaluate the efficacy of benznidazole (BZ) treatment in patients with chronic Chagas cardiomyopathy (CCC). One important question to be addressed concerns the effectiveness of BZ in reducing overall parasite load in CCC patients, even in the absence of parasitological cure. This report describes the evaluation of multiple procedures for DNA extraction and qPCR-based protocols aiming to establish a standardized methodology for the absolute quantification of T. cruzi DNA in Guanidine-EDTA blood (GEB) samples. A panel of five primer sets directed to the T. cruzi nuclear satellite DNA repeats (Sat-DNA) and to the minicircle DNA conserved regions (kDNA) was compared in either SYBR Green or TaqMan systems. Standard curve parameters such as, amplification efficiency, coefficient of determination and intercept were evaluated, as well as different procedures to generate standard samples containing pre-established T. cruzi DNA concentration. Initially, each primer set was assayed in a SYBR Green qPCR to estimate parasite load in GEB samples from chronic Chagas disease patients. The results achieved from Bayesian transmutability analysis elected the primer sets Cruzi1/Cruzi2 (p=0.0031) and Diaz7/Diaz8 (p=0.0023) coupled to the QIAamp DNA Kit extraction protocol (silica gel column), as the most suitable for monitoring parasitemia in these patients. Comparison between the parasite burden of 150 GEB samples of BENEFIT patients from Argentina, Brazil and Colombia, prior to drug/placebo administration, was performed using Cruzi1/Cruzi2 primers in a SYBR Green approach. The median parasitemia found in patients from Argentina and Colombia (1.93 and 2.31 parasite equivalents/mL, respectively) was around 20 times higher than the one estimated for the Brazilian patients (0.1 parasite equivalents/mL). This difference could be in part due to the complexity of T. cruzi genetic diversity, which is a factor possibly implicated in different clinical presentations of the disease and/or influencing parasitemia levels in infected individuals from different regions of Latin America. The results of SYBR Green qPCR assays herein presented prove this methodology to be more cost efficient than the alternative use of internal fluorogenic probes. In addition, its sensitivity and reproducibility are shown to be adequate to detect low parasitemia burden in patients with chronic Chagas disease.</abstract><cop>Netherlands</cop><pub>Elsevier B.V</pub><pmid>22982466</pmid><doi>10.1016/j.actatropica.2012.08.020</doi><tpages>9</tpages><oa>free_for_read</oa></addata></record> |
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| ispartof | Acta tropica, 2013-01, Vol.125 (1), p.23-31 |
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| recordid | cdi_proquest_miscellaneous_1272718367 |
| source | MEDLINE; Elsevier ScienceDirect Journals |
| subjects | Antiprotozoal Agents - administration & dosage Argentina BENEFIT blood Brazil Cardiac chronic Chagas disease cardiomyopathy Chagas Cardiomyopathy - drug therapy Chagas Cardiomyopathy - parasitology Chagas disease chemotherapy clinical trials Colombia DNA primers DNA, Protozoan - genetics DNA, Protozoan - isolation & purification Double-Blind Method Drug Monitoring - methods Drug Monitoring - standards genetic variation Humans kinetoplast DNA Molecular diagnosis Molecular Diagnostic Techniques - methods Molecular Diagnostic Techniques - standards monitoring Nitroimidazoles - administration & dosage parasite load Parasite Load - methods Parasite Load - standards parasitemia Parasitemia - drug therapy Parasitemia - parasitology parasites Parasitology - methods Parasitology - standards patients Placebos - administration & dosage quantitative polymerase chain reaction Randomized Controlled Trials as Topic Real-time PCR Real-Time Polymerase Chain Reaction - methods Real-Time Polymerase Chain Reaction - standards Reproducibility of Results satellite DNA Sensitivity and Specificity silica gel Specimen Handling - methods Trypanosoma cruzi Trypanosoma cruzi - isolation & purification |
| title | Towards the establishment of a consensus real-time qPCR to monitor Trypanosoma cruzi parasitemia in patients with chronic Chagas disease cardiomyopathy: A substudy from the BENEFIT trial |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-05T09%3A25%3A47IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Towards%20the%20establishment%20of%20a%20consensus%20real-time%20qPCR%20to%20monitor%20Trypanosoma%20cruzi%20parasitemia%20in%20patients%20with%20chronic%20Chagas%20disease%20cardiomyopathy:%20A%20substudy%20from%20the%20BENEFIT%20trial&rft.jtitle=Acta%20tropica&rft.au=Moreira,%20Otacilio%20C.&rft.date=2013-01&rft.volume=125&rft.issue=1&rft.spage=23&rft.epage=31&rft.pages=23-31&rft.issn=0001-706X&rft.eissn=1873-6254&rft_id=info:doi/10.1016/j.actatropica.2012.08.020&rft_dat=%3Cproquest_cross%3E1272718367%3C/proquest_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=1151701404&rft_id=info:pmid/22982466&rft_els_id=S0001706X12003063&rfr_iscdi=true |