Chil3 (YM1) antibody mouse specific - HS-442 008

Chitinase-like protein 3 (Chil3), commonly referred to as YM1, is a rodent-specific secreted glycoprotein that belongs to the chitinase-like protein (CLP) family, sharing structural similarity with true chitinases but lacking enzymatic activity. It is predominantly expressed by alternatively activated (M2) macrophages, eosinophils, and neutrophils in mice, particularly under type 2 immune conditions such as allergic inflammation, parasitic infection, and tissue repair (1). Chil3 / YM1 expression is strongly induced by IL-4 and IL-13, hallmark cytokines of Th2-driven responses. Alongside Arginase-1 (Arg1) and Fizz1 (Retnla), Chil3 / YM1 is commonly used as a biomarker of M2 macrophage polarization in murine models (2). In healthy adult mice, Chil3 / YM1 is constitutively expressed in alveolar macrophages and neutrophils in the lung and in immature neutrophils in the spleen and bone marrow (1). Its isotype Chil4 / YM2 shows a different expression pattern and is mainly expressed in the stomach (3). In the central nervous system microglia can also induce Chil3 / YM1 expression under specific inflammatory conditions, e.g. after stroke (4).