KCs are characterized by specific surface proteins such as Clec4f (C‐type lectin domain family 4, member f) and Vsig4 (V‐set and immunoglobulin domain containing 4).1, 2, 3, 4 These surface markers distinguish KCs from other hepatic macrophages, which may have lost or have yet to acquire these KC markers. The gene discussed is CLEC4F; the disease is dry eye syndrome.