title: Iraq dust is respirable, sharp, and metal-laden and induces lung inflammation with fibrosis in mice via IL-2 upregulation and depletion of regulatory T cells.
abstract: OBJECTIVE
  Determine whether surface dust grab samples taken from a large military base in Iraq are toxic and respirable.
  
  
  METHODS
  X-ray diffraction for mineral content, x-ray fluorescence for elemental content, in vivo mouse dust challenges for assessment of histological changes, bronchoalveolar lavage for cytokines, polarizing light microscopy for crystals in lung tissue, and Fluorescence Activated Cell Sorting for cell surface and intracellular markers were utilized.
  
  
  RESULTS
  Camp Victory, Iraq dust taken during wartime contains respirable particles 2.5 microns in size, constituting particulate matter air pollution. Dust particles are angular and have sharp edges. Trace metals (including titanium) calcium and silicon are present. Mice with airway instillation of dust have polarizable crystals in lung and septate inflammation. Regulatory T cells (CD4⁺CD25⁺FOXP3⁺) are decreased in thymus and spleen. Interleukin-2 (IL-2) is upregulated in bronchoalveolar lavage.
  
  
  CONCLUSIONS
  Respirable Iraq dust leads to lung inflammation in mice similar to that seen in patients with polarizable crystals, which seem to be titanium.
authors.affiliation: From the Departments of Medicine (Drs Szema and Hamidi) and Pathology (Drs Liu and Golightly and Mr Rueb), Stony Brook University School of Medicine, Stony Brook, NY; Department of Geosciences (Dr Reeder and Ms Schmidt), Stony Brook University, Stony Brook, NY; and New York University Department of Occupational and Environmental Medicine (Dr Harrington), New York.
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Szema
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Reeder
authors.forename: Andrea D
authors.initials: AD
authors.lastname: Harrington
authors.forename: Millicent
authors.initials: M
authors.lastname: Schmidt
authors.forename: Jingxuan
authors.initials: J
authors.lastname: Liu
authors.forename: Marc
authors.initials: M
authors.lastname: Golightly
authors.forename: Todd
authors.initials: T
authors.lastname: Rueb
authors.forename: Sayyed A
authors.initials: SA
authors.lastname: Hamidi
mesh_terms: D000818:Animals; D001718:Birefringence; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D002118:Calcium / Q000032:analysis; D004391:Dust / Q000032:analysis / Q000276:immunology*; D019570:Inhalation Exposure / Q000009:adverse effects*; D007376:Interleukin-2 / Q000378:metabolism*; D007493:Iraq; D018655:Lymphocyte Count; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D058749:Military Facilities; D052638:Particulate Matter / Q000737:chemistry / Q000276:immunology / Q000633:toxicity; D011014:Pneumonia / Q000209:etiology / Q000473:pathology*; D011658:Pulmonary Fibrosis / Q000209:etiology / Q000473:pathology*; D012825:Silicon / Q000032:analysis; D013154:Spleen / Q000473:pathology; D050378:T-Lymphocytes, Regulatory; D013950:Thymus Gland / Q000473:pathology; D014025:Titanium / Q000032:analysis; D015854:Up-Regulation
chemical_list: D004391:Dust; D007376:Interleukin-2; D052638:Particulate Matter; D014025:Titanium; D002118:Calcium; D012825:Silicon