Secretion of neutrophil attractant/activation protein by lipopolysaccharide-stimulated lung macrophages determined by both enzyme-linked immunosorbent assay and N-terminal sequence analysis

Am Rev Respir Dis. 1990 Mar;141(3):683-8. doi: 10.1164/ajrccm/141.3.683.


Alveolar macrophages contribute to acute pulmonary inflammation by secretion of neutrophil chemoattractants. We determined if one of these attractants is neutrophil attractant/activating protein (NAP-1), which is secreted by blood monocytes stimulated by lipopolysaccharide (LPS). Alveolar macrophages were stimulated in tissue culture with 10 micrograms/ml LPS. Culture fluids collected at 24 h were assayed for both neutrophil chemotactic activity and the concentration of NAP-1 as determined by a sandwich ELISA. The concentration of NAP-1 in culture fluid to LPS-stimulated macrophages was 860 +/- 40 ng/ml (SEM for six normal subjects). NAP-1 in fluid of unstimulated macrophages was 40 +/- 15 ng/ml. We confirmed the presence of NAP-1 in culture fluid of LPS-stimulated lung macrophages by immunoaffinity and HPLC-CM column purification. The HPLC-CM elution profile of macrophage NAP-1 was identical to that of monocyte NAP-1, and the N-terminal sequence of the protein in one of the isolated peaks corresponded to that of monocyte-derived NAP-1 beta. Two lines of evidence show that NAP-1 does not account for all neutrophil chemotactic activity in culture fluid of 24-h, LPS-stimulated macrophages. At a dilution of culture fluid that elcited the same chemotactic response as a known concentration of pure NAP-1, the concentration of culture fluid NAP-1 was only one-tenth that of pure NAP-1. (ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Cells, Cultured
  • Chemotactic Factors / analysis
  • Chemotactic Factors / isolation & purification
  • Chemotactic Factors / metabolism*
  • Chemotaxis, Leukocyte
  • Chromatography, High Pressure Liquid
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Interleukin-8
  • Interleukins / analysis
  • Interleukins / metabolism
  • Lipopolysaccharides / pharmacology*
  • Lung / cytology*
  • Macrophages / metabolism*
  • Male
  • Monocytes / metabolism
  • Peptides / analysis
  • Peptides / isolation & purification
  • Peptides / metabolism*


  • Chemotactic Factors
  • Interleukin-8
  • Interleukins
  • Lipopolysaccharides
  • Peptides