tokens: Three cell lines established from patients with VDDR-II ( Rh- VDR , Sh- VDR , and Ab- VDR ) showed no specific binding of 1 , 25 ( OH ) 2D3 to a receptor and treatment of the cultured cells with 1 , 25 ( OH ) 2D3 did not stimulate production of 24 , 25-dihydroxy-vitamin D3 ( 24 , 25 ( OH ) 2D3 ) , a response which is diagnostic of the presence of a functional 1 , 25 ( OH ) 2D3 receptor .