title: Rapid diagnosis of vitamin D-dependent rickets type II by use of phytohemagglutinin-stimulated lymphocytes.
abstract: The interactions of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] with phytohemagglutinin (PHA)-stimulated lymphocytes from normal subjects and three patients with vitamin D-dependent rickets (DDR) type II were investigated. Impaired nuclear uptake and normal cytosol binding of [3H]1,25-(OH)2D3 were observed with PHA-stimulated lymphocytes of these patients as with their cultured skin fibroblasts. Furthermore, the incorporation of [14C]thymidine into PHA-stimulated lymphocytes of the patients was not reduced by 1,25-(OH)2D3, which is known to inhibit proliferation of various cells. These findings suggest that 1,25-(OH)2D3 receptors are reduced or absent in patients with DDR type II. Thus, the capacities of cytosol binding and nuclear uptake of 1,25-(OH)2D3 in PHA-stimulated lymphocytes seem to reflect those of endo-organs such as the intestine and bone. These findings show that a test of the effect of 1,25-(OH)2D3 on thymidine incorporation into PHA-stimulated lymphocytes is useful for rapid diagnosis of DDR type II.
mesh_terms: D002117:Calcitriol / Q000494:pharmacology; D002467:Cell Nucleus / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007015:Hypophosphatemia, Familial / Q000175:diagnosis*; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000378:metabolism; D010835:Phytohemagglutinins; D018167:Receptors, Calcitriol; D011987:Receptors, Steroid / Q000378:metabolism; D012867:Skin / Q000378:metabolism; D013936:Thymidine / Q000097:blood
chemical_list: D010835:Phytohemagglutinins; D018167:Receptors, Calcitriol; D011987:Receptors, Steroid; D002117:Calcitriol; D013936:Thymidine