Chimeric synthetic peptides as diagnostic tools : a novel IgM-specific immunoassay for the diagnosis of toxoplasmosis : Driving innovation towards next-generation IgM immunoassays

Ripoll Pastor, Greta

Chimeric synthetic peptides as diagnostic tools : a novel IgM-specific immunoassay for the diagnosis of toxoplasmosis : Driving innovation towards next-generation IgM immunoassays

Document Type

Doctoral thesis
Published Version

Author

Ripoll Pastor, Greta

Director

Andreu Martínez, David
Llevadot i Esquerda, Roser

Publication Date

2021-05-10

Pages

177 p.

Citation

Ripoll Pastor, G. Chimeric synthetic peptides as diagnostic tools : a novel IgM-specific immunoassay for the diagnosis of toxoplasmosis : Driving innovation towards next-generation IgM immunoassays. 2021. handle: http://hdl.handle.net/10803/671697

This citation was generated automatically.

Doctoral program

Programa de doctorat en Biomedicina

Abstract

Serologic tests detecting anti- T. gondii IgM are the gold standard for the diagnosis of acute toxoplasmosis. Nevertheless, most commercial kits are based on lysate antigens obtained from tachyzoites grown in mice or tissue culture which present inherent limitations in terms of performance, providing erroneous results to the physicians thus hindering patient management and requiring stringent regulation. In this context, peptide-based antigens have emerged as an attractive alternative to overcome several of such issues. In this thesis we focused on designing and synthetizing a novel T. gondii IgM-specific chimeric peptide that was used to develop a chemiluminescent immunoassay for the detection of anti-T. gondii IgMs. Additionally, we aimed to assess mouse monoclonal humanized chimeric antibodies as an alternative source to the human positive plasma-derived samples that are currently used to produce reference materials, such as calibrators and controls. Along with its specific results, this thesis provides a set of innovative technologies to discover IgM-specific sequences translating them into robust antigens, to optimize immunoassay formulations, and to replace the current supply-chain of reference materials.
Les proves serològiques que detecten IgMs contra T. gondii són referents en el diagnòstic de la toxoplasmosi aguda. No obstant, la majoria de kits comercials es basen en lisats antigènics obtinguts de taquizoïts cultivats en ratolins o cultius tissulars, els quals presenten limitacions inherents en termes de rendiment, proporcionant resultats erronis als metges, dificultant per tant el maneig dels pacients i exigint una rigorosa regulació. En aquest context, els antígens basats en pèptids resulten una alternativa atractiva per a superar alguns d’aquests problemes. En aquesta tesi ens hem centrat en el disseny i síntesi d’un nou pèptid quimèric específic per la detecció de IgM contra T. gondii, que hem utilitzat per a desenvolupar un immunoassaig quimioluminescent per a la detecció d’IgMs contra T. gondii. A més, la tesi ha tingut com a objectiu avaluar una font alternativa a les mostres positives derivades del plasma humà que actualment s’utilitzen per produir materials de referència com són els calibradors i controls. Més enllà dels resultats, aquesta tesi proporciona un compendi de tecnologies innovadores per descobrir seqüències IgM específiques, traduint-les en antígens fiables, optimitzar la formulació dels immunoassaigs, substituir l’actual cadena de subministrament de materials de referència.

Keywords

Synthetic peptides, Biomaterials, Immunoassay performance, Toxoplasmosis diagnosis, IgM contra T gondii, Pèptids sintètics, Biomaterials, Rendiment immunològic, Diagnòstic de la toxoplasmosi, Anti-T. gondii IgM