Leukotriene B4 receptor 2

Leukotriene B₄ receptor 2, also known as BLT2, BLT2 receptor, and BLTR2, is an Integral membrane protein that is encoded by the LTB4R2 gene in humans and the Ltbr2 gene in mice.

Discovered several years after the leukotriene B₄ receptor 1 (BLT1), BLT2 receptor binds leukotriene B₄ (LTB₄) with far lower affinity than the BLT1 receptor does and therefore has been termed the low affinity LTB₄ receptor. Sometime after its initial discovery, the BLT2 receptor was shown to bind and become activated by several other arachidonic acid metabolites, one of which, 12-hydroxyheptadecatrienoic acid (12-HHT), has 10- to 100-fold higher affinity for it than does LTB₄; 12-HHT fails to bind or activate BLT1 receptors. While BLT2 receptors have some actions similar to BLT1 receptors, they have other actions which clearly oppose those of BLT1 in regulating inflammation and allergic responses; BLT2 receptors also have actions that extend beyond those of BLT1 receptors. Laboratory, animal, and other pre-clinical studies suggest that BLT2 receptors may be involved not only in inflammation and allergy but also in human cancer.