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.

The Klagsbrun lab has also purified N-arginine dibasic convertase, a receptor for HB-EGF that mediates cell migration. Dr. Klagsbrun's other interests include the role of semaphorins as inhibitors of tumor angiogenesis and metastasis, the characterization of tumor-derived endothelial cells, the function of growth factors and receptors in the developing zebrafish embryo, and protein phosphorylation in growth factor/receptor-mediated signaling pathways.