The microanatomy of calcium stores in human neutrophils: Relationship of structure to function

E.J. Pettit, E.V. Davies and M.B. Hallett

Molecular Signalling Group, Department of Surgery, University of Wales College of Medicine, Cardiff, U.K.

Offprint requests to: Dr. Elizabeth J . Pettit, Molecular Signalling Group, Department of Surgery, University of Wales College of Medicine, Heath Park, Cardiff CF4 4XN, UK

Summary. As changes in cytosolic free Ca²⁺ play key roles in coupling responses in neutrophils, it is important to locate and identify Ca²⁺ storage sites within these cells. Here, recent data is presented which highlights the functional link between microanatomical structure and cell signalling function. Fluorescent optical probes for cytosolic free Ca²⁺ have been used, together with organelle specific markers. We present evidence from conventional fluorescence microscopy, together with ratiometric and confocal laser scanning fluorescence microscopy, which pin-points two cellular locations for Ca²⁺ within the neutrophil; one within the nuclear lobes, and the other towards the cell periphery. Knowledge of these two locations provides a clear insight into how signalling in this cell type is regulated and provides a framework for explaining how specific stimuli act to produce specific responses. Histol Histopathol 12, 479-490 (1997)

Key words: Neutrophils, Calcium stores, Confocal microscopy, Microanatomy, Ca²⁺ signalling

DOI: 10.14670/HH-12.479