Intracellular and Extracellular Labile Iron Pools

  • Z. Ioav Cabantchik
  • Or Kakhlon
  • Silvina Epsztejn
  • Giulianna Zanninelli
  • William Breuer
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 509)


Labile forms of iron present in biological systems are defined as ionic Fe complexes that are redox active. They comprise a heterogeneous population of organic anions (phosphates and carboxylates), poly-functional ligands (i.e. chelates, siderophores and polypeptides) or surface components of membranes (e.g. phospholipid head groups) or extracellular matrix (e.g. glycans and sulfonates), which bind both forms of iron (II and III). Collectively, they define the respective labile iron pools (LIP), which can be of cellular (CLIP) or extracellular (ECLIP) nature. Operationally, those pools are characterized in terms of their propensity to engage in redox-cycling in an oxygenated environment and/or following pro-oxidant challenges. Methodologically, CLIP and ECLIP can be assessed in terms of iron reactivity and/ or the ability of the metal to undergo chelation by high affinity binding siderophores or chelators. Therapeutically, the LIPs are the immediate targets of chelators designed to reduce iron load in the entire organism, with emphasis on organs of accumulation such as the liver.


Iron Overload Hereditary Hemochromatosis Serum Iron Concentration Labile Iron Pool Metal Sensor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic/Plenum Publishers, New York 2002

Authors and Affiliations

  • Z. Ioav Cabantchik
    • 1
  • Or Kakhlon
    • 1
  • Silvina Epsztejn
    • 1
  • Giulianna Zanninelli
    • 1
  • William Breuer
    • 1
  1. 1.Alexander Silberman Institute of Life SciencesHebrew UniversityJerusalemIsrael

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