Las células tumorales liberan antioxidantes para frenar el ataque de los linfocitos T
Un estudio de la Universidad de Cambridge y OHSU publicado el 3 de septiembre identificó un mecanismo clave de evasión inmune:
- Dependencia de ROS: Los linfocitos T CD8+ citotóxicos requieren pequeñas concentraciones de especies reactivas de oxígeno (ROS) como señal activadora para desencadenar su capacidad lítica antitumoral.
- "Asfixia" inmunitaria por PRDX1: Los tumores contrarrestan este ataque secretando masivamente peroxirredoxina 1 (PRDX1), un antioxidante natural que depura los ROS del microambiente e inactiva a los linfocitos T.
- Implicancia clínica: El bloqueo de PRDX1 restauró la eficacia de la inmunoterapia en modelos resistentes. Además, el hallazgo aporta una explicación biológica directa a por qué los suplementos antioxidantes masivos han fallado o empeorado los desenlaces en ensayos oncológicos.
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