The fatty acid-binding heterocomplex FA-p34 formed by S100A8 and S100A9 is the major fatty acid carrier in neutrophils and translocates from the cytosol to the membrane upon stimulation

Exp Cell Res. 1999 Mar 15;247(2):410-21. doi: 10.1006/excr.1998.4382.


Since no data are available concerning fatty acid (FA) transport in neutrophils we studied the presence of possible FA carriers. The kFA-p34 complex, composed of S100A8 and S100A9, has been implicated in the intracellular transport of arachidonic acid and its precursors in human keratinocytes. Here, we show that FA-p34 is the major FA carrier in human neutrophils (nFA-p34). The complex is highly expressed in resting neutrophils (2.65% of cytosolic proteins) and translocates to the membrane fraction upon stimulation with opsonized zymosan. Comparison of purified nFA-p34 with kFA-p34 shows that both complexes are composed of nearly the same subunits and possess similar binding properties for oleic acid. Densitometrical analyses of 2D gels show that n and kFA-p34 contain twice as much S100A8 and S100A9 suggesting an estimated stoichiometry of (S100A8)2S100A9. A method is described allowing to distinguish n and kFA-p34 from S100A8/S100A9 homo- and heteromer complexes that are devoid of FA-binding properties. After solvent extraction, we find by GC analysis linoleic acid as major endogenous ligand of purified kFA-p34. Our results suggest that nFA-p34, might be involved in the shuttling of unsaturated FA between the cytosol and the plasma membrane of neutrophils.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Differentiation / metabolism*
  • Biological Transport
  • Calcium-Binding Proteins / metabolism*
  • Calgranulin A
  • Calgranulin B
  • Carrier Proteins / metabolism*
  • Cell Membrane / metabolism
  • Cytosol / metabolism
  • Electrophoresis, Gel, Two-Dimensional
  • Electrophoresis, Polyacrylamide Gel
  • Fatty Acids, Unsaturated / metabolism*
  • Humans
  • Immunoblotting
  • Ligands
  • Neutrophils / metabolism*
  • Rabbits
  • S100 Proteins / metabolism*


  • Antigens, Differentiation
  • Calcium-Binding Proteins
  • Calgranulin A
  • Calgranulin B
  • Carrier Proteins
  • Fatty Acids, Unsaturated
  • Ligands
  • S100 Proteins