Studies Of The Role Of Folate Recepter In Megaloblastic Anemia MDS, And Leukemia

The physiologic process of folic acid, including absorbing, transporting, and metabolism, were mediated by a specific binding protein-folate binding protein (FBP). The FBP can be separated into soluble forms (sFBP) and membrane-bound forms (mFBP) . The soluble FBP are found in serum, cerebrospid fluid and cytoplasma, called as sFR, but membrane-associated FBP, which are found in various types of cells, are divited into two kinds , folate receptor(FR) and reduced folate carrier(RFC) in recently. FR have a high-affinity to folic acid and RFC have a more-affinity to reduced folate compounds, such as 5-formyltetrahydrofolate and MTX. The RFC is only found on human placenta and neoplastic cells, and were regarded as a expression products of fetal cell.In the past two decades immence amount of data have demonstrated to be high levels of sFR in serum of megaloblastic anemia and leukemia, and shown to be two kind FBPs of FR and RFC on leukemic cells, but the significance of RFC are unknown completely. Leukemic cell were shown that RFC can increase tranport of folic acid to meet the needs of proliferotic cells in vitro. The MTX- resistant cell lines had a defective transport of MTX and decreased expression of the folate recepter. Myelodysplastic syndromes(MDS) , as a disease of dyspoiestic hematopoietic stem cell, have a disturbance of DNA synthesis, cells differentiation and some leukemic characterization. It's marrow cell display like megaloblastic change, so we postulated that folate receptor have a difference of both quantitative and quanlititive in niegalolbastic anemia, MDS and lenkemia. We measured the serum sFR and membrane-associated FR of...