7th International Chemistry Symposium "SIQ 2019" -7th Conference "Chemical Sciences"

7th International Chemistry Symposium

SIQ 2019

Síntesis de conjugados de polisacáridos capsulares de Streptococcus pneumoniae a análogos de α-galactosilceramida

Streptococcus pneumoniae is one of the fundamental causes of pneumonia, meningitis, otitis and sepsis worldwide. The main strategy to prevent these diseases is based on immunization with conjugate vaccines, where the capsular polysaccharide (CPs) is covalently linked to a carrier, usually a protein. These vaccines manage to induce powerful immune responses and generate immunological memory against the bacteria. Nowadays, the main aim is to improve the pharmacological properties of the conjugates and avoid the so-called "epitope overload effect" by replacing the carrier protein with molecules with adjuvant activity in the structure of the vaccine antigen. Alpha galactosylceramide (α-GalCer) is a glycolipid with adjuvant properties, capable of generating a powerful immune response by activating the iNKT cells. In this work, we describe the conjugation of capsular polysaccharides of S. pneumoniae to novel synthetic α-GalCer analogues as carriers; using reported conjugation methodologies, such as reductive amination, peptide coupling and multicomponent reactions such as Passerini 3-component reaction and Ugi 4-component reaction. The obtained conjugates were characterized by high-performance liquid chromatography and colorimetric methods. The identity and antigenicity of the obtained conjugates were determined by techniques such as quantitative 1H-RMN and DotBlot. The conjugates type CPs-α-GalCer-TT are immunogenic, and are able to induce an immune response type IgG similar to that generated by the conjugates containing TT. This work constitutes the first report of the employment of novel α-GalCer analogs conjugated to both PsCs of S. pneumoniae and a carrier protein as TT.

Streptococcus pneumoniae is one of the fundamental causes of pneumonia, meningitis, otitis and sepsis worldwide. The main strategy to prevent these diseases is based on immunization with conjugate vaccines, where the capsular polysaccharide (CPs) is covalently linked to a carrier, usually a protein. These vaccines manage to induce powerful immune responses and generate immunological memory against the bacteria. Nowadays, the main aim is to improve the pharmacological properties of the conjugates and avoid the so-called "epitope overload effect" by replacing the carrier protein with molecules with adjuvant activity in the structure of the vaccine antigen. Alpha galactosylceramide (α-GalCer) is a glycolipid with adjuvant properties, capable of generating a powerful immune response by activating the iNKT cells. In this work, we describe the conjugation of capsular polysaccharides of S. pneumoniae to novel synthetic α-GalCer analogues as carriers; using reported conjugation methodologies, such as reductive amination, peptide coupling and multicomponent reactions such as Passerini 3-component reaction and Ugi 4-component reaction. The obtained conjugates were characterized by high-performance liquid chromatography and colorimetric methods. The identity and antigenicity of the obtained conjugates were determined by techniques such as quantitative 1H-RMN and DotBlot. The conjugates type CPs-α-GalCer-TT are immunogenic, and are able to induce an immune response type IgG similar to that generated by the conjugates containing TT. This work constitutes the first report of the employment of novel α-GalCer analogs conjugated to both PsCs of S. pneumoniae and a carrier protein as TT.

About The Speaker

Dayan Viera Barredo

Lic. Dayan Viera Barredo

IFV - Instituto Finlay de Vacunas Flag of Cuba
Practical Info
English (US)
Not defined
30 minutes
Not defined
Authors
Yanira mendez gomez
Ana rodriguez humpierre
Dayan viera barredo
Vicente vérez bencomo
Abel zanuy reguera
Aldrin vasco milán
Barbara baró bicet
Raine garrido arteaga
Daniel garcía rivera
Dagmar garcía rivera
Lic. Dayan Viera Barredo
Keywords
conjugados
pneumoniae
α-galactosilceramida