Suppression of Inhaled Particle Cytotoxicity by Pulmonary Surfactant and Re-Toxification by Phospholipase: Distinguishing Properties of Quartz and Kaolin

Details

• Personal Author:
  Castranova, Vincent ; Green FHY ; Hathaway P ; Keane MJ ; Regad ED ; Vallyathan V ; Wallace WE Jr.
• Description:
  Inhaled particle contact with pulmonary surfactant in the hypophase lining pulmonary alveoli was modelled in vitro by exposing two respirable sized dusts, kaolin and silica quartz, to lecithin, a major component of pulmonary surfactant, emulsified in physiological saline. Lecithin adsorbs to the dusts upon incubation at 37 degrees-C and suppresses their cytotoxicity as measured by pulmonary macrophage and erythrocyte assays, suggesting that pulmonary surfactant provides a defence system against prompt cell membrane lysis by inhaled dusts. Subsequent pulmonary macrophage phagocytosis and lysosomal enzyme digestion of the coated dusts was modelled in vitro by incubation with phospholipase A2 for one hour. With increasing lipase activity, silica haemolytic potential was restored to native silica levels. Kaolin was retoxified to levels far in excess of native kaolin haemolytic potential Elution, thin layer chromatography and phosphate assay of treated dusts indicate that most lecithin on silica is digested to lysolecithin and desorbed, silica retoxification being due to surface and adherent lysolecithin effects. Most lecithin on kaolin is not digested in the same time; that which is, results in adherent lysolecithin which is responsible for the kaolin retoxification. Digestion with phospholipases A2 and C together produces only weakly retoxified kaolin. Results suggest that surface adsorption properties which control the adherence of prophylactic surfactant distinguish the pathogenic potentials of quartz, kaolin and mixed dust. [Description provided by NIOSH]
• Subjects:
  Cells, Cultured Cytotoxins Dust Lung Occupational Health Respiratory System Safety Surface-Active Agents
• Keywords:
  Cell-cultures Cell-function Cellular-function Cytotoxic-effects Pulmonary-clearance Pulmonary-function Respirable-dust Surfactants
• ISBN:
  0080341853
• ISSN:
  0003-4878
• Publisher:
  Pergamon Press
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DRDS - Division of Respiratory Disease Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  291-298
• Volume:
  32
• NIOSHTIC Number:
  nn:20032630
• Citation:
  Ann Occup Hyg, Inhaled Particles VI 1988 Dec; 32(Suppl 1):291-298
• CAS Registry Number:
  Kaolin (CAS RN 1332-58-7) ; Quartz (SiO2) (CAS RN 14808-60-7)
• Editor(s):
  Dodgson J; McCallum RI; Bailey MR; Fisher DR
• Federal Fiscal Year:
  1989
• Peer Reviewed:
  True
• Source Full Name:
  Annals of Occupational Hygiene, Inhaled Particles VI
• Supplement:
  1
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:57a705214cc1430be0a5970a8acdb5debe34f79e20f007d1a67a054b61e7be158278681a02fce8c4820c3c5b53a5230ffc8830c868707032f55114f1125abf95
• Download URL:
  https://stacks.cdc.gov/view/cdc/186533/cdc_186533_DS1.pdf
• File Type:
  [PDF - 490.98 KB ]