TPI-1 is a potent and selective, orally-active protein tyrosine phosphatases SHP-1 inhibitor with IC50 of 40 nM (0.01 ug/ml).
TPI-1 has limited impact on recombinant MKP1 (IC50> 1 ug/ml) or SHP-2 (IC50 ~ 0.1 ug/ml).
TPI-1 selectively increases SHP-1 phospho-substrates (pLck-pY394, pZap70, and pSlp76) in Jurkat T cells at low nM, does not affect pLck-pY505 or pERK1/2.
TPI-1 induces mouse splenic-IFN-gamma(+) cells, also induces IFN-γ(+) cells in human peripheral blood in vitro.
TPI-1 inhibits the growth of B16 melanoma tumors in mice in a T cell-dependent manner.
