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La regulación de la migración de leucocitos mediante la activación de la molécula de adhesión leucocitaria-1 (LAM-1)
O Spertini1, G S Kansas, J M Munro
1Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, Massachusetts.
Nature
|February 21, 1991
Resumen
La afinidad de la molécula de adhesión de leucocitos-1 (LAM-1) aumenta tras la activación, controlando la migración de leucocitos a los tejidos durante las respuestas inmunes. Esto explica cómo diferentes tipos de leucocitos migran específicamente.
Área de la Ciencia:
- Inmunología Inmunología.
- Biología celular Biología celular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La migración de leucocitos a los tejidos es crucial para la defensa del huésped contra los patógenos y la inflamación.
- La molécula de adhesión de leucocitos-1 (LAM-1) media la unión de los leucocitos a las células endoteliales, guiando a los linfocitos a los ganglios linfáticos y a los neutrófilos a los sitios inflamatorios.
- El mecanismo que controla la migración de leucocitos específicos del linaje a través de LAM-1, a pesar de la expresión compartida, sigue sin estar claro.
Objetivo del estudio:
- Investigar cómo se controlan las diferencias específicas del linaje en la migración de leucocitos.
- Determinar el papel de la modulación de afinidad LAM-1 en el tráfico de leucocitos.
Principales métodos:
- Se evaluó la afinidad de LAM-1 para su ligando, PPME, en linfocitos y neutrófilos activados y no activados.
- Estudió la unión dependiente de LAM-1 de los linfocitos a las venas endoteliales altas después de la activación por estímulos fisiológicos.
Principales resultados:
- La activación de leucocitos por estímulos específicos del linaje aumentó significativamente la afinidad LAM-1 por el ligando de carbohidratos PPME.
- La activación de los linfocitos aumentó la unión mediada por LAM-1 a las venas endoteliales altas.
Conclusiones:
- Los cambios transitorios en la afinidad LAM-1 después de la activación de leucocitos regulan directamente la migración de leucocitos.
- La modulación de la afinidad LAM-1 proporciona un mecanismo para controlar el tráfico de leucocitos específico del linaje durante las respuestas inmunes.
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