A sensitive and reliable quantitative immunohistochemistry technique to evaluate the percentage of Trypanosoma cruzi-infected tissue area

Quantification 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.

Palavras-chave

Cardiomyopathy, Cardiac biopsies, Endomyocardial biopsies, Anti-T. cruzi antibodies

URI

https://observatorio.fm.usp.br/handle/OPI/39308

Referências

Bilate AM, 2008, J INFECT DIS, V198, P614, DOI 10.1086/590347
Caldas S, 2012, ACTA TROP, V123, P170, DOI 10.1016/j.actatropica.2012.05.002
Caliari MV, 2002, VIRCHOWS ARCH, V441, P69, DOI 10.1007/s00428-001-0542-4
Cobo ED, 2012, J TROP MED-US, V2012, DOI 10.1155/2012/232646
Ezyaguirre E.J., 2011, DIAGNOSTIC IMMUNOHIS, P58, DOI [10.1016/B978-1-4160-5766-6.00007-8, DOI 10.1016/B978-1-4160-5766-6.00007-8]
Greenfield E.A., 2014, ANTIBODIES LAB MANUA, P2014
Guarner J, 2001, AM J TROP MED HYG, V65, P152, DOI 10.4269/ajtmh.2001.65.152
HIGUCHI MD, 1993, CARDIOVASC PATHOL, V2, P101, DOI 10.1016/1054-8807(93)90021-S
Lewis MD, 2016, TRENDS PARASITOL, V32, P899, DOI 10.1016/j.pt.2016.08.009
Dias JCP, 2016, REV SOC BRAS MED TRO, V49, P3, DOI 10.1590/0037-8682-0505-2016
Portela-Lindoso AAB, 2003, REV SAUDE PUBL, V37, P107, DOI 10.1590/S0034-89102003000100016
Azevedo PHR, 2018, REV SOC BRAS MED TRO, V51, P467, DOI 10.1590/0037-8682-0011-2018
Ferreira JCR, 2019, EXP PARASITOL, V200, P13, DOI 10.1016/j.exppara.2019.03.007
Santoro F, 1987, Rev Soc Bras Med Trop, V20, P91, DOI 10.1590/S0037-86821987000200005
Simões Marcus Vinicius, 2018, Int. J. Cardiovasc. Sci., V31, P173, DOI 10.5935/2359-4802.20180011
YOUNESCHENNOUFI AB, 1988, T ROY SOC TROP MED H, V82, P77, DOI 10.1016/0035-9203(88)90269-6

Coleções

Artigos e Materiais de Revistas Científicas - FM/MPE
Artigos e Materiais de Revistas Científicas - IMT
Artigos e Materiais de Revistas Científicas - LIM/06
Artigos e Materiais de Revistas Científicas - LIM/17
Artigos e Materiais de Revistas Científicas - LIM/38
Artigos e Materiais de Revistas Científicas - LIM/48

Página do item completo