Should we measure serum or plasma lead concentrations?
Serum or heparin plasma separated from blood samples collected via venous phlebotomy with or without vacuum are appropriate medium to assess Pb concentrations, independently of the sample standing time.
TNF-alpha suppresses erythropoiesis by inhibiting the generation of GPA+ cells derived from CD34+ cells as well as by inhibiting the proliferative capacity of GPA+ cells. Although the presence of TNFRs does not directly indicate that the receptor(s) mediates death signaling, altered expression of TNFRs depending on the level of maturation may imply altered sensitivities to TNF-alpha in various stage of erythroid progenitors.