Tyrosine Protein Kinase Receptors (Tek, Tie-1, and Tie-2) Antibodies

M= Mouse; R=Rat; H=Human; Rb=Rabbit; G=goat; B=Bovine, MO=Monkey; P=pig; CT= near C-terminus; NT=near N-terminus; Internal=Middle of protein. EC=extracellular; CP=cytoplasmic domains *


TIEs (Tek) General Information

Embryonic vascular system undergoes a series of complex, highly regulated series of events involving differentiation, migration and association of primitive endothelial cells. This process is termed vasculogenesis. A further remodeling of the primitive vascular system forms the mature cardiovascular system. This process is known as angiogenesis (sprouting of new capillary vessels from pre-existing vasculature). The development of primordia of the heart and large vessels, primary capillary networks in the embryo and the extraembryonic structures in the yolk sac. Angiogenesis accounts for the formation of vasculature into previously avascular organs such as brain and kidney. Angiogenic activity in the adult is required during the normal tissue repair, and for the remodeling of the female reproductive organs (ovulation and placental development). Certain pathological conditions, such as tumor growth and diabetic retinopathy, also require angiogenesis. The genetic and molecular mechanism that influence angiogenesis has only recently begun to be studied and identified. Study of tumor angiogenesis has led to the identification of several proteins including basic fibroblast growth factor (bFGF) and vascular endothelial growth factor. VEGF acts by interacting with a family of largely endothelial-specific receptor tyrosine kinases that includes VEGFR-1 (flt-1), VEGFR-2 (flk-1/KDR), and VEGFR-3/Flt-4. Disruption of VEGFRs interferes with differentiation of endothelial cells and it is lethal for the embryo.

Another families of receptor tyrosine kinases TIE1 and TIE 2 or Tek have also been identified in vascular endothelium and hematopoietic cells. Mice lacking TIE 1 or TIE 2 are lethal. Ties may represent the earliest endothelial cell lineage marker and may regulate the endothelial cell proliferation, differentiation, and proper patterning during vasculogenesis. TIEs appear to be acting downstream of the VEGFRs. In order to delineate the mechanism of actions of the Tie receptors, novel cloning techniques have been used to identify their natural ligands.

ADI has produced highly specific antibodies to Ang-1 and Ang-2 and their receptors (Tie-1 and Tie-2) using specific peptide sequences. In addition, purified recombinant VEGFs, antibodies to VEGFs, and their receptors are also available. The control peptides, used for immunization, are also available to determine specificity of antibodies.