Provided are drugs for preventing and treating autoimmune diseases or allergic diseases, drugs for preventing and treating diseases involving Th17 cells and cell inhibitors for Th17 cells that comprise anti-Embigin antibodies, particularly anti-Embigin antibodies that have cell-inhibiting activity or cell inhibition-inducing activity. Also provided are agents for detecting Th17 cells that comprise anti-Embigin antibodies, a simple assay method for Th17 cells that uses same, a method for selectively and efficiently delivering drugs to Th17 cells using anti-Embigin antibodies, and a system for delivering drugs to Th17 cells.
