Please use this identifier to cite or link to this item: https://www.arca.fiocruz.br/handle/icict/6894
Title: Anti-Leishmania chagasi immunoglobulin G3 detected by flow cytometry for early cure assessment in American visceral leishmaniasis
Authors: Gomes, Izabelle Teixeira
Carvalho, Sílvio Fernando Guimarães de
Rocha, Roberta Dias Rodrigues
Magalhães, Vanessa Peruhype
Dietze, Reynaldo
Martins Filho, Olindo Assis
Lemos, Elenice Moreira
Affilliation: Universidade Federal do Espírito Santo. Núcleo de Doenças Infecciosas. Laboratório de Leishmanioses. Vitória, Espírito Santo, Brazil/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Biomarcadores de Diagnóstico e Monitoração. Belo Horizonte, MG, Brazil
Universidade Estadual de Montes Claros. Montes Claros, MG, Brazil
Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Biomarcadores de Diagnóstico e Monitoração. Belo Horizonte, MG, Brazil
Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Biomarcadores de Diagnóstico e Monitoração. Belo Horizonte, MG, Brazil
Universidade Federal do Espírito Santo. Núcleo de Doenças Infecciosas. Laboratório de Leishmanioses. Vitória, Espírito Santo, Brazil
Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Biomarcadores de Diagnóstico e Monitoração. Belo Horizonte, MG, Brazil
Universidade Federal do Espírito Santo. Núcleo de Doenças Infecciosas. Laboratório de Leishmanioses. Vitória, Espírito Santo, Brazil
Abstract: We have previously reported a novelflowcytometric based methodology to access the reactivity of seric anti-live (FC-ALPA) andfixed (FC-AFPA)L. chagasiIgG antibodies applicable for cure assessment after specific therapy of VL. Both, FC-ALPA-IgGand FC-AFPA-IgGare promising targets to be used for early cure assessment. However, ourfinding suggested that further refinements were still required to improve the performance of FC-AFPA IgG for early cure assessment inVL. In the present investigation, we have established and evaluated the performance of FC-AFPA-IgG1/IgG2/IgG3/IgG4 aiming to increase theperformance indexof the previously reported for FC-AFPA-IgG. Thedatawas expressedaspercentageoffluorescent positiveparasites after incubationof pre-fixedL. Chagasi promastigotes with the test sera samples and additionof second-step FITC-labeled anti-human IgG subclasses conjugates. The analysis of anti-L. chagasi IgG reactivity in polled será samples from VL patients demonstrated that, before the etiological treatment, the IgG subclass profile was characterized by IgG1NIgG3 with the absence of IgG2 and IgG4 at the specifics era dilution tested. Following the establishment of specific PPFP cut-off-edges to segregate negative and positive results (PPFP of 50% for FC-AFPA-IgG1 and PPFP of 40% for FC-AFPA-IgG3), the analysis of IgG1 and IgG3 reactivity demonstrated good performance for early cure assessment in VL. The analysis of individual samples indicated that despite at 2 mAT, most treated VL patients (81%) still displayed positive results in FC-AFPA-IGg1 analysis, an increased fraction of treated patients (76%) presentednegative inFC-AFPA-IgG1 analysis at 6 mAT. Interestingly, thedata from FC-AFPA-IgG3demonstratedanoutstandingperformance of thismethod toearly cure assessment inVLwith increased frequency of treated patients displaying negative results at 2 mAT (90.5%) aswell as at 6 mAT (95.2%). The analysis of likelihood ratio (LR) further confirmed the remarkable performance of FC-AFPA-IgG3 as an early complementary biomarker useful to monitor the post-therapeutic cure in human VL.
Keywords: Leishmania chagasi
IgG3 Flow cytometry
Cure assessment
Visceral leishmaniasis
Issue Date: 2010
Publisher: Elsevier
Citation: GOMES, Izabelle Teixeira et al. Anti-Leishmania chagasi immunoglobulin G3 detected by flow cytometry for early cure assessment in American visceral leishmaniasis. J Immunol Methods. 2010 Aug 31;360(1-2):76-83.
DOI: 10.1016/j.jim.2010.06.011
Copyright: restricted access
Appears in Collections:MG - IRR - Artigos de Periódicos

Files in This Item:
File Description SizeFormat 
51.2010.pdf1.04 MBAdobe PDFThumbnail
    Request a copy



FacebookTwitterDeliciousLinkedInGoogle BookmarksBibTex Format mendeley Endnote DiggMySpace

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.