On the expression of cytosolic calcium‐independent phospholipase A2 (88 kDa) in immature and mature myeloid cells and its role in leukotriene synthesis in human granulocytes

FEBS Letters

Runarsson, Gudmundur²  Larsson Forsell, Pontus K.A.¹  Björkholm, Magnus²  Claesson, Hans-Erik¹  Ibrahim, Mirna¹ 

[1] Department of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institute, S-171 77 Stockholm, Sweden;Department of Medicine, Division of Hematology and Infectious Diseases, Karolinska Hospital, S-171 76 Stockholm, Sweden

关键词: Phospholipase A2;    Arachidonic acid;    Leukotriene;    Bromoenol lactone;   

DOI  :  10.1016/S0014-5793(98)00999-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The human calcium-independent phospholipase A₂ (iPLA₂; 88 kDa) has recently been cloned (Larsson, P.K.A., Claesson, H.-E. and Kennedy, B.P. (1998) J. Biol. Chem. 272, 207–214). Here we demonstrate the expression of the human iPLA₂ mRNA and its splice variants in blood progenitor cells, immature leukemic cells and mature granulocytes. Chromatographical resolvable iPLA₂ activity was found in the cytosolic fraction of granulocytes and the activity was inhibited by the iPLA₂ inhibitor bromoenol lactone. This drug also inhibited leukotriene synthesis in human granulocytes, induced by low concentration of calcium ionophore A23187 (0.10–0.15 μM) or opsonized zymosan. These results suggest that iPLA₂ is involved in the regulation of the pool of arachidonic acid destined for leukotriene synthesis in human granulocytes.

【 授权许可】

Unknown