Trypanosoma cruzi : Evaluation of PCR as a Laboratory Tool to Follow up the Evolution of Parasite Load

• Published in: Iranian journal of parasitology Vol. 11; no. 3; pp. 389 - 395
• Main Authors: Ferraz, Fabiana Nabarro, Aleixo, Denise Lessa, Gruendling, Ana Paula, Gomes, Mônica Lúcia, Toledo, Max Jean de Ornelas, DE Araújo, Silvana Marques
• Format: Journal Article
• Language: English
• Published: Iran Tehran University of Medical Sciences 01.07.2016
• Subjects: Colleges & universities; Deoxyribonucleic acid; Dilution; DNA; Genetic testing; kDNA fragments; Laboratories; Parasite load; Parasites; PCR; Protozoa; Short Communication; Trypanosoma cruzi; Brazil; kDNA fragments; PCR; Parasite load; Trypanosoma cruzi
• ISSN: 1735-7020

The study evaluated qualitative PCR, primers 121-122 as a tool to follow up evolution parasite load of . The study was conducted at the State University of Maringa, in 2015. Step 1, dilutions 1/10 were performed from -Y strain to obtain preparations of 50,000-0.05 parasites/mL from which DNA were extracted, quantified, and amplified. Step 2, the extracted DNA in the dilutions 5-0.05 parasites/mL was re-diluted 1/10, 1/100, 1/1000, quantified, and amplified. Polyacrylamide gels were photographed and thicknesses of the 330 bp kDNA fragments were measured. Step 1, in the dilutions 50,000-50 parasites/mL kDNA fragments had same thickness and, dilutions 5-0.05 parasites/mL showed progressive decrease in thicknesses and staining intensity of the 330 bp fragments. Step 2, demonstrated that dilutions of five (re-dilutions 1/10 and 1/100) and 0.5 (1/10) parasites/mL produced similar thicknesses of the 330 bp fragments obtained in Step 1. However, very dilute DNA samples make difficult to reproduce the fragments thicknesses. PCR, despite its limitations, was able to detect progressive decrease in thicknesses/staining intensity of kDNA fragments in the dilutions 5-0.05 parasites/mL. Hence, has the potential to be used to follow-up evolution of parasite load, not by quantifying the number of parasites, but by dynamic evolution of the fragments thicknesses during etiological treatment.