Immunodiagnosis of Paracoccidioidomycosis due to Paracoccidioides brasiliensis Using a Latex Test: Detection of Specific Antibody Anti-gp43 and Specific Antigen gp43

Autor(es)

dos Santos, Priscila Oliveira ^[1] ; Rodrigues, Anderson Messias ^[1] ; Fernandes, Geisa Ferreira ^[1] ; Marques da Silva, Silvia Helena ^[2] ; Burger, Eva ^[3] ; de Camargo, Zoilo Pires ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Dept Microbiol Immunol & Parasitol, Div Cell Biol, Sao Paulo - Brazil

^[2] Evandro Chagas Inst, Bacteriol & Mycol Div, Ananindeua, Para - Brazil

^[3] Univ Fed Alfenas, Inst Biomed Sci, Alfenas, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLoS Neglected Tropical Diseases; v. 9, n. 2 FEB 2015.
• Citações Web of Science: 5

Resumo

Background Paracoccidioidomycosis (PCM) is a life-threatening systemic disease and is a neglected public health problem in many endemic regions of Latin America. Though several diagnostic methods are available, almost all of them present with some limitations. Method/Principle Findings A latex immunoassay using sensitized latex particles (SLPs) with gp43 antigen, the immunodominant antigen of Paracoccidioides brasiliensis, or the monoclonal antibody mAb17c (anti-gp43) was evaluated for antibody or antigen detection in sera, cerebrospinal fluid (CSF), and bronchoalveolar lavage (BAL) from patients with PCM due to P. brasiliensis. The gp43-SLPs performed optimally to detect specific antibodies with high levels of sensitivity (98.46%, 95% CI 91.7-100.0), specificity (93.94%, 95% CI 87.3-97.7), and positive (91.4%) and negative (98.9%) predictive values. In addition, we propose the use of mAb17c-SLPs to detect circulating gp43, which would be particularly important in patients with immune deficiencies who fail to produce normal levels of immunoglobulins, achieving good levels of sensitivity (96.92%, 95% CI 89.3-99.6), specificity (88.89%, 95% CI 81.0-94.3), and positive (85.1%) and negative (97.8%) predictive values. Very good agreement between latex tests and double immune diffusion was observed for gp43-SLPs (k = 0.924) and mAb17c-SLPs (k = 0.850), which reinforces the usefulness of our tests for the rapid diagnosis of PCM in less than 10 minutes. Minor cross-reactivity occurred with sera from patients with other fungal infections. We successfully detected antigens and antibodies from CSF and BAL samples. In addition, the latex test was useful for monitoring PCM patients receiving therapy. Conclusions/Significance The high diagnostic accuracy, low cost, reduced assay time, and simplicity of this new latex test offer the potential to be commercialized and makes it an attractive diagnostic assay for use not only in clinics and medical mycology laboratories, but mainly in remote locations with limited laboratory infrastructure and/or minimally trained community health workers. (AU)

• Processo FAPESP: 11/07350-1 - Biologia do complexo Sporothrix schenckii: Análise de marcadores moleculares e proteômicos e o papel de moléculas antigênicas e antifúngicas na esporotricose
• Beneficiário: Anderson Messias Rodrigues
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 09/54024-2 - Biologia molecular e proteômica de fungos de interesse médico: Paracoccidioides brasiliensis e Sporothrix schenckii
• Beneficiário: Zoilo Pires de Camargo
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 09/54181-0 - Padronizacao da tecnica de aglutinacao em latex para diagnostico rapido de paracoccidioidomicose: deteccao de anticorpos e antigenos circulantes.
• Beneficiário: Zoilo Pires de Camargo
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/01628-8 - Análise proteômica de isolados de Sporothrix schenckii diferentes entre si quanto à virulência através da técnica de iTRAQ/2-D LC-MS/MS
• Beneficiário: Geisa Ferreira Fernandes Sovegni
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado