Serological response to pgp3 protein in animal and human chlamydial infections

Donati, Manuela; Laroucau, Karine; Storni, Elisa; Mazzeo, Costanza; Magnino, Simone; Francesco, Antonietta Di; Baldelli, Raffaella; Ceglie, Letizia; Renzi, M.; Cevenini, Roberto

doi:10.1016/j.vetmic.2008.09.037

Cited by 20 publications

(14 citation statements)

References 19 publications

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“…These studies have used the multiplex bead array platform (Bio-rad, Hercules, California) to detect antibodies against Pgp3 and CT694, antigens thought to be highly immunogenic [25]. Because this platform is costly, technically complex and unlikely to be found in most laboratories in resource-limited regions, alternative, simpler methods of antibody detection have been proposed [22,26]. …”

Section: Introductionmentioning

confidence: 99%

Defining Seropositivity Thresholds for Use in Trachoma Elimination Studies

et al. 2017

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BackgroundEfforts are underway to eliminate trachoma as a public health problem by 2020. Programmatic guidelines are based on clinical signs that correlate poorly with Chlamydia trachomatis (Ct) infection in post-treatment and low-endemicity settings. Age-specific seroprevalence of anti Ct Pgp3 antibodies has been proposed as an alternative indicator of the need for intervention. To standardise the use of these tools, it is necessary to develop an analytical approach that performs reproducibly both within and between studies.MethodologyDried blood spots were collected in 2014 from children aged 1–9 years in Laos (n = 952) and Uganda (n = 2700) and from people aged 1–90 years in The Gambia (n = 1868). Anti-Pgp3 antibodies were detected by ELISA. A number of visual and statistical analytical approaches for defining serological status were compared.Principal FindingsSeroprevalence was estimated at 11.3% (Laos), 13.4% (Uganda) and 29.3% (The Gambia) by visual inspection of the inflection point. The expectation-maximisation algorithm estimated seroprevalence at 10.4% (Laos), 24.3% (Uganda) and 29.3% (The Gambia). Finite mixture model estimates were 15.6% (Laos), 17.1% (Uganda) and 26.2% (The Gambia). Receiver operating characteristic (ROC) curve analysis using a threshold calibrated against external reference specimens estimated the seroprevalence at 6.7% (Laos), 6.8% (Uganda) and 20.9% (The Gambia) when the threshold was set to optimise Youden’s J index. The ROC curve analysis was found to estimate seroprevalence at lower levels than estimates based on thresholds established using internal reference data. Thresholds defined using internal reference threshold methods did not vary substantially between population samples.ConclusionsInternally calibrated approaches to threshold specification are reproducible and consistent and thus have advantages over methods that require external calibrators. We propose that future serological analyses in trachoma use a finite mixture model or expectation-maximisation algorithm as a means of setting the threshold for ELISA data. This will facilitate standardisation and harmonisation between studies and eliminate the need to establish and maintain a global calibration standard.

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Section: Introductionmentioning

confidence: 99%

Defining Seropositivity Thresholds for Use in Trachoma Elimination Studies

et al. 2017

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“…trachomatis. The literature describes various antigenic proteins of the pathogen, including cell wall proteins; however, the most immunogenic is the major outer membrane protein, the plasmid protein Pgp3, as well as HSP-60 and HSP-70 are the most immunogenic ones [10][11][12][13][14]. Manufacturers of commercial diagnostic kits usually use only one type of antigen to detect antibodies by certain test-kit [15][16][17].…”

Section: Resultsmentioning

confidence: 99%

Development and characterization of highly informative ELISA for the detection of IgG and IgA antibodies to Сhlamydia trachomatis

Galkin¹,

Gorshunov²,

Besarab³

et al. 2018

Ukr.Biochem.J

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The goal of this work was developing of highly informative an enzyme-linked immunosorbent assay (elISa) for the detection of IgG and Iga antibodies against to Chlamydia trachomatis, as well as comparative characterization of developed assay using standardized control materials. The study was conducted using: monoclonal antibodies (Mcabs) to human Iga and IgG; recombinant Ch. trachomatis proteins-Pgp3, major outer membrane protein (MOMP); two panels of characterized sera and four reference elISa kits. The study of immunochemical activity of peroxidase conjugates of Mcabs was performed in comparison with conjugates of commercial analogues: anti-IgG Mcab 2a11 and anti-Iga Mcab aD3. about half of the conjugates from the received McAbs panel were more active compared to the reference antibody conjugates. It was quite justified to use the conjugates of antibodies that interact with different antigenic determinants. When IgG antibodies were detected to MOMP, it was justified 1.14-1.56 times more; when IgA antibodies were detected to MOMP, it was justified 1.16-1.37 times more. ELISA for detecting IgG/IgA antibodies to MOMP and Pgp3 of Ch. trachomatis were evaluated using appropriately described serum panels OCO-42-28-313-00 and OCO-42-28-314-00. Comparative studies of the developed elISa for the detection of IgG and Iga antibodies to the MOMP and Pgp3 of Ch. trachomatis showed their prominent advantage over the commercial analogues, which more clearly demonstrates the difference in the ratio of average values of optical density of positive and negative samples of the described panel of sera: this indicator for commercial kits was 1.36-3.59 times less.

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“…Experiments using urogenital isolates of C. trachomatis with plasmids where CDS5 has been deleted revealed significantly reduced bacterial burdens in the genital tracts of mice, mimicking the properties of the plasmid-free (P -) strains (Liu et al 2014;Ramsey et al 2014). As most patients infected with C. trachomatis produce an antibody response to PGP3 (Bas et al 2001b;Comanducci et al 1994;Donati et al 2009;Ghaem-Maghami et al 2003;Goodhew et al 2012;Wills et al 2009), these properties make PGP3 an ideal antigen for detecting anti-C. trachomatis antibodies for use in ELISA formats for both diagnosis and seroprevalence.…”

Section: Accepted Manuscriptmentioning

confidence: 98%

“…Previous studies that used ELISA or multiplex assay to detect prior C. trachomatis exposure used PGP3 derived from various serovars of C. trachomatis, including L1 (Wills et al 2009) and a urogenital strain, D (Bas et al 2001a;Comanducci et al 1994;Donati et al 2009;Ghaem-Maghami et al 2003;Goodhew et al 2012). PGP3 from urogenital serovars D and E and PGP3 from the LGV serovar L1 vary by nine amino acids with different hydrophobic/hydrophilic characteristics (S1 appendix).…”

Section: Accepted Manuscriptmentioning

confidence: 99%