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Invasion of Human Cells by a Bacterial Pathogen
Published on: March 21, 2011
Streptococcus pneumoniae se ancla a las células humanas activadas por el receptor del factor de activación
D R Cundell1, N P Gerard, C Gerard
1Laboratory of Molecular Infectious Diseases, Rockefeller University, New York, New York 10021-6399, USA.
Nature
|October 5, 1995
Resumen
Streptococcus pneumoniae utiliza el receptor del factor de activación plaquetaria (PAF) para las infecciones virulentas. Dirigirse a este receptor con antagonistas puede ofrecer una nueva estrategia terapéutica contra las enfermedades neumocócicas como la neumonía y la meningitis.
Área de la Ciencia:
- Microbiología Microbiología.
- Inmunología Inmunología.
- Interacciones patógeno-anfitrión.
Sus antecedentes:
- Streptococcus pneumoniae causa enfermedades invasivas graves como la neumonía, la sepsis y la meningitis.
- Muchas personas asintomáticamente albergan neumococos en la nasofaringe, lo que resalta la necesidad de comprender los factores que diferencian la colonización de la enfermedad invasiva.
Objetivo del estudio:
- Investigar los mecanismos moleculares que distinguen el transporte asintomático de las infecciones invasivas por Streptococcus pneumoniae.
- Para identificar las interacciones huésped-patógeno que dictan el resultado de la enfermedad.
Principales métodos:
- Se investigó la orientación bacteriana de los receptores de las células huésped durante la activación inflamatoria.
- Se utilizan antagonistas específicos de los receptores para bloquear la adhesión e invasión bacteriana.
- Se evaluó la adhesión bacteriana a través de la interacción de la fosforilcolina con el receptor de PAF.
Principales resultados:
- La activación inflamatoria redirige la orientación neumocócica hacia el receptor del factor de activación plaquetaria (PAF, por sus siglas en inglés).
- Sólo las cepas virulentas de neumococos activan el receptor de PAF.
- La unión de la fosforilcolina bacteriana al receptor de PAF mejora la adherencia y promueve la invasión de varios tipos de células humanas.
Conclusiones:
- La activación del receptor PAF por Streptococcus pneumoniae virulento es un paso crítico en la enfermedad invasiva.
- Los antagonistas de los receptores de FAP pueden inhibir la adherencia y la invasión neumocócicas in vitro e in vivo.
- Los antagonistas de los receptores de FAP representan una vía terapéutica potencial para el tratamiento de las infecciones neumocócicas.
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