IL-9 can refer to:
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Interleukin 9
Interleukin 9, also known as IL-9, is a pleiotropic cytokine (cell signalling molecule) belonging to the group of interleukins. IL-9 is produced by variety of cells like mast cells, NKT cells, Th2, Th17, Treg, ILC2, and Th9 cells in different ...
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Illinois' 9th congressional district
The 9th congressional district of Illinois covers parts of Cook, Lake, and McHenry counties as of the 2021 redistricting which followed the 2020 census. All or parts of Chicago, Evanston, Glenview, Skokie, Morton Grove, Niles, Northfield, ...
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Illinois Route 9
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