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Reactividad de los linfocitos T infiltrados con antígenos microbianos en la enfermedad de Crohn
U Pirzer1, A Schönhaar, B Fleischer
1First Department of Medicine, University of Mainz, Germany.
Lancet (London, England)
|November 16, 1991
Resumen
Las células T en el intestino inflamado de la enfermedad de Crohn pierden su falta de respuesta normal a los antígenos microbianos. Esto sugiere que estos linfocitos T pueden impulsar la inflamación intestinal crónica al reaccionar a las bacterias intestinales.
Área de la Ciencia:
- Inmunología Inmunología.
- Gastroenterología y Gastroenterología.
- Biología celular Biología celular.
Sus antecedentes:
- Los linfocitos T (células T) en el intestino generalmente no responden a los antígenos microbianos y recuerdan los antígenos in vitro.
- Las células T de la sangre periférica, sin embargo, montan fuertes respuestas inmunes a estos mismos antígenos.
- Esta diferencia sugiere un mecanismo regulador especializado para las células T intestinales.
Objetivo del estudio:
- Para investigar la capacidad de respuesta de las células T de la mucosa intestinal en pacientes con enfermedad de Crohn.
- Para determinar si la falta de respuesta normal de las células T intestinales se mantiene en el intestino inflamado.
Principales métodos:
- Se recogieron linfocitos T de la sangre periférica y la mucosa intestinal (inflamatoria y no inflamatoria) de 6 pacientes con enfermedad de Crohn.
- Células T estimuladas in vitro con varios antígenos microbianos.
- Se evaluó la proliferación de células T como una medida de la respuesta inmune.
Principales resultados:
- Las células T de la mucosa intestinal normal no respondieron a los antígenos microbianos, de acuerdo con la fisiología conocida.
- Las células T de la mucosa intestinal inflamada exhibieron una respuesta proliferativa similar a las células T derivadas de la sangre periférica.
- Esto indica que la falta de respuesta a los antígenos luminales se pierde en las lesiones intestinales inflamadas.
Conclusiones:
- La falta de respuesta fisiológica a los antígenos luminales se anula en las lesiones intestinales inflamadas de los pacientes con enfermedad de Crohn.
- Los linfocitos T infiltrados en las lesiones de la enfermedad de Crohn pueden mediar la inflamación crónica al encontrarse con antígenos intestinales.
- Esta pérdida de tolerancia contribuye a la comprensión de la patogénesis de la enfermedad de Crohn.
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