KELLY APARECIDA KANUNFRE
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina
LIM/48 - Laboratório de Imunologia, Hospital das Clínicas, Faculdade de Medicina
LIM/48 - Laboratório de Imunologia, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
- A new Real Time PCR with species-specific primers from Plasmodium malariae/P. brasilianum mitochondrial cytochrome b gene(2020) SANTOS, Emilly Henrique dos; YAMAMOTO, Lidia; DOMINGUES, Wilson; SANTI, Silvia Maria di; KANUNFRE, Kelly Aparecida; OKAY, Thelma SuelyPlasmodium malariae mainly causes asymptomatic submicroscopic parasitemia in the endemic Amazon and non-endemic Atlantic Forest, where the number of cases and transmission of malaria through blood transfusion has increased. This study developed a P. malariae/P. brasilianum Real Time PCR (rtPCR) targeting the cytochrome b oxidase (cytb), a highly repetitive gene (20-150 copies/parasite) that should detect more cases than the 18S rRNA (4-8 copies/parasite) gene-based amplification systems. Cytb from human and non-human Plasmodium species (including P. brasilianum) aligned to the only 20 African P. malariae cytb sequences identified polymorphic regions within which we designed P. malariae species-specific primers. Non-human Plasmodium species, related parasites, anemia-causing microorganisms, normal human DNA and 47 blood bank donors samples that were truly negative to malaria accessed rtPCR specificity. Truly positive samples (n = 101) with species identification by semi-nested, nested or TaqMan PCR, and four samples from the Atlantic Forest that were suspected of malaria but three of them had negative genus TaqMan and 18S rRNA nested PCR. The cloned amplification product used in standard curves determined qPCR detection limit (0.5-1 parasite equivalent/mu L). The 10 positive P. malariae samples among truly positives yielded positive rtPCR results and more importantly, rtPCR detected the four samples suspected of malaria from the Atlantic Forest. The rtPCR specificity was 100%, reproducibility 11.1% and repeatability 6.7%. In conclusion, the proposed rtPCR is fast, apparently more sensitive than all 18S rRNA amplification systems for detecting extremely low parasitemia. The rtPCR is also specific to P. malariae/P. brasilianum species. This new molecular tool could be applied to the detection of P. malariae/brasilianum infections with submicroscopic parasitemias in the context of epidemiological studies and blood bank safety programs.
- A sensitive and reliable quantitative immunohistochemistry technique to evaluate the percentage of Trypanosoma cruzi-infected tissue area(2021) FERREIRA-FILHO, Julio Cesar Rente; BRAZ, Lucia Maria Almeida; ANDRINO, Marcos Luiz Alves; YAMAMOTO, Lidia; KANASHIRO, Edite Hatsumi Yamashiro; SILVA, Ana Maria Goncalves da; KANUNFRE, Kelly Aparecida; OKAY, Thelma SuelyQuantification of parasites in the context of Chagas disease is required to monitor the treatment with benznidazole, disease-associated cardiomyopathies and graft rejection after heart transplantation. As parasitological exams lack sensitivity, Real Time Polymerase Chain Reaction (rt-PCR) has emerged to evaluate the parasite load in blood samples and cardiac biopsies. However, despite its higher sensitivity, rt-PCR does not provide information on the location and distribution of amastigote nests within infected tissues, the characterization of inflammatory infiltrates or changes to tissue architecture. On the contrary, a sensitive immunohistochemistry technique (IHC) could fill these gaps. In the present study, a quantitative IHC exam was standardized and validated by testing adipose and cardiac tissues of experimentally infected mice containing variable parasite load levels of T. cruzi assessed by a sensitive Sybr Green rt-PCR with kDNA primers. Tissues were divided into four groups according to the parasite load: group A100 parasites/50 ng of DNA; group B-10 parasites; group C - around 1 parasite and group D less than 1 parasite/50 ng/DNA. IHC was able to detect T. cruzi in the four groups, even in group D tissues containing fractions of a single parasite/50 ng of DNA sample according to rt-PCR. In conclusion, a highly sensitivity and reliable quantitative immunohistochemistry technique was developed and is proposed to estimate the percentage of T. cruzi-infected tissue area in chagasic patients presenting with cardiomyopathies, as a complementary test to rt-PCR.