Quantification of annexin I in subcellular fractions of human neutrophils reveals an exclusive cytosolic localisation

Cell Biol Int. 2001;25(10):963-9. doi: 10.1006/cbir.2001.0760.


Annexin I is an abundant cytosolic protein in human neutrophils. Besides its intracellular location, annexin I is found as an extracellular protein and the pathway for secretion has been of interest since the protein lacks a signal sequence for secretion. It was recently shown that annexin I is stored in the secretory gelatinase granules of human neutrophils, suggesting that the protein might be released through a granule mobilisation and fusion process resembling classical secretion. In this study we have determined the intracellular localisation of annexin I in human neutrophils using subcellular fractionation, protein separation by SDS-PAGE and immunoblotting, and show that virtually all annexin I is localised in the cell cytosol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Annexin A1 / analysis*
  • Cells, Cultured
  • Cytosol / chemistry
  • Humans
  • Immunoblotting
  • Neutrophils / chemistry*
  • Subcellular Fractions / chemistry


  • Annexin A1