Michael Klagsbrun has made major contributions to the field of growth factors and their receptors, particularly those that regulate the vascular system. He is credited with the first purifications of basic fibroblast growth factor (FGF-2), a potent angiogenesis factor, and of heparin-binding EGF-like growth factor (HB-EGF).

More recently, Dr. Klagsbrun's laboratory has purified several growth factor receptors. One of these, neuropilin, is a novel receptor for the angiogenesis factor VEGF that was originally described as a receptor for semaphorin, a molecule involved in regulating the direction of neuronal growth. These studies have suggested that similar molecular mechanisms regulate angiogenesis and neuronal guidance, both of which are networking processes.