Subtractive phage display selection for screening and identification of peptide sequences with potential use in serodiagnosis of paracoccidioidomycosis caused by Paracoccidioides brasiliensis.

Abstract

Paracoccidioidomycosis (PCM) is a systemic granulomatous disease endemic in Latin America whose aetiologic agents are the thermodimorphic fungi Paracoccidioides brasiliensis and Paracoccidioides lutzii. Despite technological advances, some problems have been reported for the fungal antigens used for serological diagnosis, and inconsistencies among laboratories have been reported. The use of synthetic peptides in the serological diagnosis of infectious diseases has proved to be a valuable strategy because in some cases, the reactions are more specific and sensitive. In this study, we used a subtractive selection with a phage display library against purified polyclonal antibodies for negative and positive PCM sera caused by P. brasiliensis. The binding phages were sequenced and tested in a binding assay to evaluate its interaction with sera from normal individuals and PCM patients. Synthetic peptides derived from these phage clones were tested in a serological assay, and we observed a significant recognition of LP15 by sera from PCM patients infected with P. brasiliensis. Our results demonstrated that subtractive phage display selection may be useful for identifying new epitopes that can be applied to the serodiagnosis of PCM caused by P. brasiliensis.

SIGNIFICANCE AND IMPACT OF THE STUDY:

Currently, there is no standardized method for the preparation of paracoccidioidomycosis (PCM) antigens, which has resulted in differences in the antigens used for serological diagnosis. Here, we report a procedure that uses subtractive phage display selection to select and identify new epitopes for the serodiagnosis of PCM caused by Paracoccidioides brasiliensis. A synthetic peptide obtained using this methodology was successfully recognized by sera from PCM patients, thus demonstrating its potential use for improving the serodiagnosis of this mycosis. The development of synthetic peptides for the serodiagnosis of PCM could be a promising alternative for the better standardization of diagnoses among laboratories.

• Authors: L da Silva Portes, E S Kioshima, Z P de Camargo, W L Batista, P Xander
• Journal: Letters in applied microbiology (Lett Appl Microbiol) Vol. 65 Issue 5 Pg. 346-353 (Nov 2017) ISSN: 1472-765X [Electronic] England
• PMID: 28796894 (Publication Type: Evaluation Study, Journal Article)
• Copyright: © 2017 The Society for Applied Microbiology.

Chemical References

• Antibodies, Fungal
• Antigens, Fungal
• Peptide Library
• Peptides

Topics

• Antibodies, Fungal (blood)
• Antigens, Fungal (blood, immunology)
• Bacteriophages (genetics, metabolism)
• Humans
• Male
• Middle Aged
• Paracoccidioides (genetics, immunology, isolation & purification)
• Paracoccidioidomycosis (blood, diagnosis, microbiology)
• Peptide Library
• Peptides (genetics, immunology)
• Serologic Tests (instrumentation, methods)