CVI
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Neves, A. R.
Right arrow Articles by Blotta, M. H. S. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Neves, A. R.
Right arrow Articles by Blotta, M. H. S. L.
Clinical and Diagnostic Laboratory Immunology, September 2003, p. 802-807, Vol. 10, No. 5
1071-412X/03/$08.00+0     DOI: 10.1128/CDLI.10.5.802-807.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

Negative Immunodiffusion Test Results Obtained with Sera of Paracoccidioidomycosis Patients May Be Related to Low-Avidity Immunoglobulin G2 Antibodies Directed against Carbohydrate Epitopes

Andréia R. Neves,1 Ronei L. Mamoni,1 Cláudio L. Rossi,1 Zoilo P. de Camargo,2 and Maria Heloísa S. L. Blotta1*

Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas,1 Discipline of Cellular Biology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil2

Received 9 December 2002/ Returned for modification 13 February 2003/ Accepted 21 March 2003

Immunodiffusion (ID) is the serologic test most frequently used for the diagnosis and posttherapy follow-up of patients with paracoccidioidomycosis (PCM). The ID test is highly specific (100%), but its sensitivity is relatively low (90%), leading to false-negative results. The aim of this study was to determine the profiles of antibodies in sera from patients with proven PCM and with negative results in the ID test (IDneg) versus positive results in the ID test (IDpos). We analyzed 46 sera from patients with active PCM for total immunoglobulin G (IgG) and IgG subclass responses to Paracoccidioides brasiliensis gp43 antigen (treated or not treated with sodium metaperiodate) by enzyme-linked immunosorbent assay and immunoblotting. Immunoblotting showed that both IDneg and IDpos sera recognized predominantly the gp43 fraction of the P. brasiliensis antigen used in the ID test. IDneg sera contain low-avidity antibodies, low levels of specific IgG (total) and IgG1, and high levels of IgG2 compared with IDpos sera. The antibodies present in IDneg sera were predominantly directed against carbohydrate epitopes, since treatment with sodium metaperiodate resulted in a significant decrease in antibody reactivity. These data suggest that the lack of reactivity of sera from PCM patients in the ID test may be related to the production of low-avidity IgG2 antibodies directed against carbohydrate epitopes.

* Corresponding author. Mailing address: Department of Clinical Pathology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), P.O. Box 6111, 13083-970 Campinas, São Paulo, Brazil. Phone: 55-19-37889453. Fax: 55-19-37889434. E-mail: heblotta{at}fcm.unicamp.br.

Clinical and Diagnostic Laboratory Immunology, September 2003, p. 802-807, Vol. 10, No. 5
1071-412X/03/$08.00+0     DOI: 10.1128/CDLI.10.5.802-807.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Antimicrob. Agents Chemother. Clin. Microbiol. Rev. Infect. Immun.
J. Clin. Microbiol. J. Virol. ALL ASM JOURNALS

Copyright © 2003 by the American Society for Microbiology. All rights reserved.