title: Measurement of the pulmonary vascular granulocyte pool.
abstract: We have developed a technique for measuring the pulmonary granulocyte pool (PGP) as a fraction of the whole body total blood granulocyte pool (TBGP). The technique "captures" a dose of 99mTc-labeled granulocytes in a region of interest (ROI) over the lung during first pass by integrating an input time-activity curve from an ROI over the pulmonary artery, superior vena cava, or right ventricle. The ratio of the estimated first-pass count rate and the count rate in the same lung ROI after equilibration of the cells between the circulating and pulmonary pools (15-30 min) represents the PGP/TBGP. The technique was validated in eight subjects by using 99mTc-labeled macroaggregated human serum albumin. With corrections for background and injected doses, the ratios of first-pass granulocyte-to-macroaggregated human serum albumin count rates given by the three input ROIs were close to unity [superior vena cava 0.98 +/- 0.079 (SD), right ventricle 1.01 +/- 0.070, and pulmonary artery 0.97 +/- 0.073]. Significant increases in PGP/TBGP were demonstrated in systemic inflammation. Thus, in patients with inflammatory bowel disease, it was 0.22 +/- 0.07 (n = 7) compared with 0.08 +/- 0.01 (n = 5) in control subjects. It was also elevated in patients with systemic vasculitis (0.34 +/- 0.07; n = 5), in transplant recipients (0.33 +/- 0.08; n = 5), and in patients with osteomyelitis (0.15 +/- 0.06; n = 4). We conclude that this is a valid technique for quantifying the PGP that is expanded in several conditions associated with systemic inflammation.
authors.affiliation: Department of Radiology, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom.
authors.forename: W Y
authors.initials: WY
authors.lastname: Ussov
authors.forename: A M
authors.initials: AM
authors.lastname: Peters
authors.forename: D M
authors.initials: DM
authors.lastname: Glass
authors.forename: R D
authors.initials: RD
authors.lastname: Gunasekera
authors.forename: J M
authors.initials: JM
authors.lastname: Hughes
mesh_terms: D001783:Blood Flow Velocity; D003952:Diagnostic Imaging; D006086:Graft vs Host Disease / Q000097:blood / Q000175:diagnosis; D006098:Granulocytes / Q000000981:diagnostic imaging* / Q000473:pathology / Q000502:physiology; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000097:blood / Q000175:diagnosis; D007958:Leukocyte Count; D008168:Lung / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000378:metabolism; D010019:Osteomyelitis / Q000097:blood / Q000175:diagnosis; D011651:Pulmonary Artery / Q000000981:diagnostic imaging* / Q000378:metabolism; D011877:Radionuclide Imaging; D013668:Technetium Tc 99m Aggregated Albumin; D014683:Vena Cava, Superior / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin