title: Imaging Inflammation in Asthma: Real Time, Differential Tracking of Human Neutrophil and Eosinophil Migration in Allergen Challenged, Atopic Asthmatics in Vivo.
abstract: BACKGROUND
  It is important to study differential inflammatory cellular migration, particularly of eosinophils and neutrophils, in asthma and how this is influenced by environmental stimuli such as allergen exposure and the effects of anti asthma therapy.
  
  
  METHODS
  We isolated blood neutrophils and eosinophils from 12 atopic asthmatic human volunteers (Group 1 - four Early Allergic Responders unchallenged (EAR); Group 2 - four Early and Late Allergic Responders (LAR) challenged; Group 3 - four EAR and LAR challenged and treated with systemic corticosteroids) using cGMP CD16 CliniMACS. Cells were isolated prior to allergen challenge where applicable, labelled with (99m)Tc-HMPAO and then re-infused intravenously. The kinetics of cellular influx/efflux into the lungs and other organs were imaged via scintigraphy over 4 h, starting at 5 to 6 h following allergen challenge where applicable.
  
  
  RESULTS
  Neutrophils and eosinophils were isolated to a mean (SD) purity of 98.36% (1.09) and 96.31% (3.0), respectively. Asthmatic neutrophils were activated at baseline, mean (SD) CD11b(High) cells 46 (10.50) %. Isolation and radiolabelling significantly increased their activation to > 98%. Eosinophils were not activated at baseline, CD69(+) cells 1.9 (0.6) %, increasing to 38 (3.46) % following isolation and labelling. Analysis of the kinetics of net eosinophil and neutrophil lung influx/efflux conformed to a net exponential clearance with respective mean half times of clearance 6.98 (2.18) and 14.01 (2.63) minutes for Group 1, 6.03 (0.72) and 16.04 (2.0) minutes for Group 2 and 5.63 (1.20) and 14.56 (3.36) minutes for Group 3. These did not significantly differ between the three asthma groups (p > 0.05).
  
  
  CONCLUSIONS
  Isolation and radiolabelling significantly increased activation of eosinophils (CD69) and completely activated neutrophils (CD11b(High)) in all asthma groups. Net lung neutrophil efflux was significantly slower than that of eosinophils in all asthma study groups. There was a trend for pre-treatment with systemic corticosteroids to reduce lung retention of eosinophils following allergen challenge.
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK ; King's College London, Department of Asthma, Allergy & Respiratory Science, 5th Floor, Tower Wing, Guy's Hospital, London SE1 9RT, UK.
authors.forename: Joanna J
authors.initials: JJ
authors.lastname: Lukawska
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK ; Department of Nuclear Medicine, Guy's and St. Thomas' Hospitals, London SE1 9RT, UK.
authors.forename: Lefteris
authors.initials: L
authors.lastname: Livieratos
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK.
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Sawyer
authors.affiliation: King's College London, Department of Asthma, Allergy & Respiratory Science, 5th Floor, Tower Wing, Guy's Hospital, London SE1 9RT, UK ; Allergy Centre, HK Sanatorium and Hospital, Hong Kong.
authors.forename: Tak
authors.initials: T
authors.lastname: Lee
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK ; Department of Nuclear Medicine, Guy's and St. Thomas' Hospitals, London SE1 9RT, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: O'Doherty
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK ; Division of Chemistry, King's College London, SE1 9RT London, UK.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Blower
authors.affiliation: Department of Nuclear Medicine, Guy's and St. Thomas' Hospitals, London SE1 9RT, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: Kofi
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK ; Department of Nuclear Medicine, Guy's and St. Thomas' Hospitals, London SE1 9RT, UK.
authors.forename: James R
authors.initials: JR
authors.lastname: Ballinger
authors.affiliation: King's College London, Department of Asthma, Allergy & Respiratory Science, 5th Floor, Tower Wing, Guy's Hospital, London SE1 9RT, UK.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Corrigan
authors.affiliation: Department of Nuclear Medicine, Guy's and St. Thomas' Hospitals, London SE1 9RT, UK.
authors.forename: Gopinath
authors.initials: G
authors.lastname: Gnanasegaran
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Sharif-Paghaleh
authors.affiliation: Kings College London, Division of Imaging Sciences and Bioengineering, St. Thomas' Hospital, London SE1 7EH, UK.
authors.forename: Gregory E D
authors.initials: GE
authors.lastname: Mullen
keywords: Allergen challenge; Asthma; Eosinophils; Migration kinetics; Neutrophils; Radioisotope