“Imagine a fisherman who gets a bite, but is not strong enough to reel it in alone, so he sounds an alarm that brings others in to help,” analogizes Michael Caterina, M.D., Ph.D., associate professor of biological chemistry, Johns Hopkins University School of Medicine. “That’s similar to what’s happening here: A macrophage receptor will bind to a giant germ it encounters, but not tightly enough to secure it. So TRPV2 on the macrophage acts as an alarm: It tells the other receptors around the macrophage to consolidate in that one place to enhance the local binding of that bacteria.” Credit: Johns Hopkins