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El desencadenamiento del receptor tipo peaje de una respuesta antimicrobiana humana mediada por vitamina D
Philip T Liu1, Steffen Stenger, Huiying Li
1Department of Microbiology, Immunology, and Molecular Genetics, University of California at Los Angeles, Los Angeles, CA 90095, USA.
Science (New York, N.Y.)
|February 25, 2006
Resumen
La activación del receptor Toll-like (TLR) en los macrófagos humanos aumenta la vitamina D, mejorando el péptido antimicrobiano catelicidina para combatir el Mycobacterium tuberculosis. Los niveles más bajos de vitamina D en ciertas poblaciones se correlacionan con una mayor susceptibilidad a la tuberculosis.
Área de la Ciencia:
- Inmunología Inmunología.
- Microbiología Microbiología.
- Ciencias de la Nutrición Ciencias de la Nutrición
Sus antecedentes:
- Los receptores tipo peaje (TLR) activan la inmunidad innata contra las bacterias intracelulares.
- El óxido nítrico media la actividad antimicrobiana inducida por TLR en los macrófagos murinos, pero no humanos.
- El papel de la vitamina D en la inmunidad innata humana contra Mycobacterium tuberculosis sigue siendo objeto de investigación.
Objetivo del estudio:
- Investigar el mecanismo de la actividad antimicrobiana inducida por TLR en los macrófagos humanos.
- Para explorar el papel de la vitamina D en la inmunidad innata mediada por TLR contra Mycobacterium tuberculosis.
- Examinar la asociación entre los niveles de vitamina D, la inducción de catelicidina y la susceptibilidad a la tuberculosis.
Principales métodos:
- Activación de los receptores de tipo Toll (TLR) en los macrófagos humanos.
- Medición del receptor de vitamina D y la expresión génica de la vitamina D-1-hidroxilasa.
- Evaluación de la inducción de catelicidina y la matanza de Mycobacterium tuberculosis.
- Análisis de los niveles de 25-hidroxivitamina D y la inducción del ARN mensajero de catelicidina en suero humano.
Principales resultados:
- La activación de TLR regula al alza el receptor de vitamina D y la expresión génica de la vitamina D-1-hidroxilasa en los macrófagos humanos.
- Esto condujo a la inducción del péptido antimicrobiano catelicidina y la matanza mejorada de Mycobacterium tuberculosis intracelular.
- Se observaron niveles bajos de 25-hidroxivitamina D y una inducción ineficiente del ARN mensajero de catelicidina en sueros de individuos afroamericanos, que han aumentado la susceptibilidad a la tuberculosis.
Conclusiones:
- Existe un vínculo entre los receptores de tipo Toll (TLR) y la inmunidad innata mediada por la vitamina D.
- La vitamina D juega un papel crucial en la respuesta de los macrófagos humanos a la Mycobacterium tuberculosis.
- Las variaciones en la producción de vitamina D entre las poblaciones humanas pueden influir en la susceptibilidad a infecciones microbianas como la tuberculosis.
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