Interleukin-1β stimulates galectin-9 expressions in human astrocytes

Galectin-9 is an eosinophil chemoattractant produced by activated T lymphocytes. We have addressed expression of galectin-9 in normal human astrocytes in culture. Expression of galectin-9 mRNA and protein were examined by reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescent staining. Interleukin-1 beta (IL-1 beta) was found to enhance the galectin-9 expression in time- and concentration-dependent manners. Galectin-9 protein was detected in the membrane fi-action, 105 000 x g precipitate, and immunofluorescent staining revealed diffuse cellular and perinuclear distributions. Dexamethasone pretreatment almost completely suppressed the production. We conclude that astrocytes produce galectin-9 in response to the stimulation with IL-1 beta, and this may contribute to inflammatory reactions in the CNS. NeuroReport 12:3755-3758 (C) 2001 Lippincott Williams & Wilkins.