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La alfa 4 beta 7 integrina media la unión de los linfocitos a la dirección vascular de la mucosa con la MAdCAM-1-1
C Berlin1, E L Berg, M J Briskin
1Department of Pathology, Stanford University, California 94305.
Cell
|July 16, 1993
Resumen
La integrina alfa 4 beta 7 de los linfocitos se une a la addressina vascular de la mucosa, MAdCAM-1, que guía las células inmunes al intestino. Esta interacción es crucial para que los linfocitos se dirijan a los tejidos de la mucosa.
Área de la Ciencia:
- Inmunología Inmunología.
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La addressina vascular mucosa (MAdCAM-1) se expresa por las venas de la mucosa.
- MAdCAM-1 dirige el tráfico de linfocitos hacia los parches de Peyer y la lámina intestinal propia.
- La integrina alfa 4 beta 7 de los linfocitos está implicada en la localización de los parches de Peyer.
Objetivo del estudio:
- Para identificar el receptor de MAdCAM-1 en los linfocitos.
- Para investigar el papel de la integrina alfa 4 beta 7 en la unión a MAdCAM-1.
- Para dilucidar los mecanismos moleculares de los linfocitos que se dirigen a los sitios de la mucosa.
Principales métodos:
- Inhibición mediada por anticuerpos de la unión de los linfocitos a MAdCAM-1.
- Análisis de las interacciones entre linfocitos y MAdCAM-1 utilizando transfectantes MAdCAM-1.
- Investigando el efecto de la activación de la integrina en la afinidad de unión.
Principales resultados:
- La integrina alfa 4 beta 7 de los linfocitos es un receptor directo para MAdCAM-1.
- Los anticuerpos a las cadenas alfa 4 y beta 7 inhiben la unión, mientras que los anticuerpos anti-LFA-1 no lo hacen.
- MAdCAM-1 es un ligando preferente para alfa 4 beta 7 en comparación con VCAM-1.
Conclusiones:
- La interacción entre alfa 4 beta 7 y MAdCAM-1 es selectiva.
- Esta interacción juega un papel crítico en la orientación de los linfocitos hacia los tejidos de la mucosa.
- Los hallazgos proporcionan información sobre la base molecular de la inmunidad de la mucosa.
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