Disclosed is a monoclonal antibody that specifically binds an epitope within amino acids 71-80 of the human IAP (integrin-associated protein) and is an antagonist of IAP to SHPS-1 (Src homology 2 domain-containing protein tyrosine phosphatase substrate 1) binding. Also disclosed is a method of inhibiting IGF-1 actions in a subject by the use of the antibody.