title: Frequency of transferrin receptor positive reticulocytes (TF-Ret) in blood as an indicator of total-body radiation exposure: a pilot study in nuclear medicine patients.
abstract: Approximately 3-20% of all reticulocytes in blood of healthy persons are immature and transferrin receptor positive (Tf-Ret). Tf-Ret were measured by flow cytometry in 27 patients treated with three different radiopharmaceuticals labeled with (131)I and in 25 healthy controls. Patients were chronically exposed within 6 days to blood doses from 0.18-1.89 Gy (D6). Typically, two-thirds of D6 was administered within the first day (D1). The study had to be confined to intra-subject investigations due to high biological variability of Tf-Ret counts. A significant radiation-induced decline was found in patients D1 doses that were ≥0.5 Gy. Tf-Ret frequency declined during the first 4 to 5 days of nuclear therapy to about 30-60% of its initial value, and increased in the following 3 days without reaching the initial value. At the time of nadir, the relative frequency of Tf-Ret was more depressed than that of reticulocytes and lymphocytes. The relative Tf-Ret frequency at nadir could be fitted to the equation: %-Tf-Ret=exp-(D1/D(o)). D(o) was found to be 1.0 ± 0.4 Gy (Mean ± SEM). The study shows that Tf-Ret frequency in blood might be a good parameter for estimation of the radiation dose to red marrow.
authors.affiliation: Department of Nuclear Medicine, University of Wuerzburg, Oberduerrbacher Strasse 6, D-97080, Wuerzburg, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Hempel
authors.forename: Heribert
authors.initials: H
authors.lastname: Haenscheid
authors.forename: Johannes
authors.initials: J
authors.lastname: Biko
authors.forename: Maria
authors.initials: M
authors.lastname: Hategan
authors.forename: Franz
authors.initials: F
authors.lastname: Kaiser
authors.forename: Michael
authors.initials: M
authors.lastname: Kreissl
authors.forename: Reinhard
authors.initials: R
authors.lastname: Lorenz
authors.forename: Samuel
authors.initials: S
authors.lastname: Samnick
authors.forename: Andreas
authors.initials: A
authors.lastname: Schirbel
authors.forename: Lali
authors.initials: L
authors.lastname: Varazashvili
authors.forename: Stanislav
authors.initials: S
authors.lastname: Verchenya
authors.forename: Christoph
authors.initials: C
authors.lastname: Reiners
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001853:Bone Marrow / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D005045:Etomidate / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D005260:Female; D005909:Glioblastoma / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011990:Receptors, Transferrin / Q000378:metabolism / Q000528:radiation effects; D017701:Reticulocyte Count; D012156:Reticulocytes / Q000378:metabolism / Q000528:radiation effects; D013964:Thyroid Neoplasms / Q000532:radiotherapy*; D014916:Whole-Body Irradiation
chemical_list: D011990:Receptors, Transferrin; C529450:iodophenyl metomidate; D005045:Etomidate