Cytosolic free Ca2+ concentration was measured and imaged in human neutrophils moving towards a source of formylated peptide in a micropipette held close to the cells. Under these conditions, neutrophils changed shape and displayed chemotaxis without significant or persistent global or localised elevations in cytosolic free Ca2+. A rear-to-front persistent Ca2+ gradient of less than 0.5 nM/micron was present in the migrating neutrophils, until they reached the zone of higher peptide concentration, when an abrupt rise in cytosolic free Ca2+ concentration was triggered and chemotaxis stopped. Small localised rises in cytosolic free Ca2+, which were occasionally observed during neutrophil manoeuvring, were attributed to the effect of local deformation of the neutrophil membrane, since deformation of the membrane with a blunt micropipette caused similar Ca2+ changes. These data suggest that neutrophil chemotaxis towards a source of formylated peptide occurs without significant changes in Ca2+ signalling.

Al-Mohanna
F. A.
,
Hallett
M. B.
(
1988
).
The use of fura2 to determine the relationship between intracellular free Ca2+and oxidase activation in rat neutrophils.
Cell Calcium
8
,
17
26
Al-Mohanna
F. A.
,
Hallett
M. B.
(
1990
).
Actin polymerization in neutrophils is triggered without a requirement for a rise in cytoplasmic free Ca2+.
Biochem. J
266
,
669
–.
Boitano
S.
,
Dirksen
E. R.
,
Sanderson
M. J.
(
1992
).
Intercellular propagation of Ca2+waves mediated by inositol trisphosphate.
Science
258
,
292
298
Boucek
M. M.
,
Snyderman
R.
(
1976
).
Calcium influx requirement for human neutrophil chemotaxis: inhibition by lanthanum chloride.
Science
193
,
905
907
Boulay
F.
,
Tardif
M.
,
Brouchon
L.
,
Vignais
P.
(
1990
).
The human N-formylpeptide receptor. Characterisation of two cDNA isolates and evidence for a new subfamily of G-protein-coupled receptors.
Biochemistry
29
,
11123
11133
Brundage
R. A.
,
Fogarty
K. E.
,
Tuft
R. A.
,
Fay
F. S.
(
1993
).
Chemotaxis of newt eosinophils: calcium regulation of chemotactic response.
Am. J. Physiol
265
,
1527
–.
Davies
E. V.
,
Hallett
M. B.
,
Campbell
A. K.
(
1991
).
Localised superoxide release by neutrophils can be provoked by a cytosolic calcium ‘cloud’.
Immunology
73
,
228
234
Downey
G. P.
,
Chan
C. K.
,
Trudel
S.
,
Grinstein
S.
(
1990
).
Actin assembly in electropermeabilised neutrophils: role of intracellular calcium.
J. Cell Biol
110
,
1975
1982
Gilbert
S. H.
,
Perry
K.
,
Fay
F. S.
(
1994
).
Mediation of chemoattractant-induced changes in [Ca2+]iand cell shape change, polarity and locomotion by InsP3, DAG and protein kinase C in newt eosinophils.
J. Cell Biol
127
,
489
503
Goligorsky
M. S.
(
1988
).
Mechanical stimulation induces Ca2+transients and membrane depolarization in cultured endothelial cells.
FEBS Lett
240
,
59
63
Hallett
M. B.
,
Campbell
A. K.
(
1982
).
Measurement of changes in cytoplasmic free calcium in fused cell hybrids.
Nature
294
,
155
158
Hallett
M. B.
,
Davies
E. V.
,
Campbell
A. K.
(
1990
).
Oxidase activation in individual neutrophils is dependent on the onset and magnitude of the Ca2+signal.
Cell Calcium
11
,
655
663
Hendey
W.
,
Maxfield
F. R.
(
1993
).
Regulation of neutrophil motility and adhesion by intracellular calcium transients.
Blood Cells
19
,
143
164
Howard
T.
,
Chapponnier
C.
,
Yin
H.
,
Stossel
T.
(
1990
).
Gelsolin-actin interactions and actin polymerization in human neutrophils.
J. Cell Biol
110
,
1983
1991
Huang
C. K.
,
Bonak
V. A.
,
Laramee
G. R.
,
Casnellie
J. E.
(
1990
).
Protein tyrosine phosphorylation in rabbit peritoneal neutrophils.
Biochem. J
269
,
431
436
Keller
H. U.
,
Bessis
M.
(
1975
).
Migration and chemotaxis of anucleate cytoplasmic leukocyte fragments.
Nature
258
,
723
724
Lansman
J. B.
,
Hallam
T. J.
,
Rink
T. J.
(
1983
).
Single stretch-activated ion channels in vascular endothelial cells as mechanotransducers?.
Nature
325
,
811
813
Lloyds
D.
,
Brindle
N. J. P.
,
Hallett
M. B.
(
1995
).
Priming of human neutrophils by substance P and TNF-is associated with tyrosine phosphorylation.
Immunology
84
,
220
226
Malawista
S. E.
,
Chevance
A.
(
1982
).
The cytokineplast: purification, stability and functional motile machinery from human polymorphonuclear leukocytes.
J. Cell Biol
95
,
960
973
Marks
P. W.
,
Maxfield
F. R.
(
1990
).
Transient increases in cytosolic free calcium appear to be required for the migration of adherent human neutrophils.
J. Cell. Biol
110
,
43
52
Marks
P. W.
,
Maxfield
F. R.
(
1990
).
Local and global changes in cytosolic free calcium in neutrophils during chemotaxis and phagocytosis.
Cell Calcium
11
,
181
190
Marks
P. W.
,
Hendey
B.
,
Maxfield
F. R.
(
1991
).
Attachment to fibronectin or vitronectin makes human neutrophil migration sensitive to alterations in cytosolic free calcium concentration.
J. Cell Biol
112
,
149
158
Meshulam
T.
,
Proto
P.
,
Diamond
R. D.
,
Melnick
D. A.
(
1986
).
Calcium modulation and chemotactic response: divergent stimulation of neutrophil chemotaxis and cytosolic calcium response by the chemotactic receptor.
J. Immunol
137
,
1954
1960
Murphy
P. M.
(
1994
).
The molecular biology of chemoattractant receptors.
Annu. Rev. Immunol
12
,
593
633
Ng-Sikorgski
J.
,
Andersson
R.
,
Patarroyo
M.
,
Andersson
T.
(
1991
).
Calcium signalling capacity of the CD11b/CD18 integrin on human neutrophils.
Exp. Cell Res
195
,
504
508
Perez
H.
,
Elfman
F.
,
Marde
S.
,
Lobo
E.
,
Elves
H.
(
1989
).
F-met-leu-phe induced chemotaxis of human neutrophils does not require marked changes in cytosolic Ca2+or specific granule discharge.
J. Clin. Invest
83
,
1963
1970
Petersen
M.
,
Williams
J. D.
,
Hallett
M. B.
(
1993
).
Cross-linking of CD11b or CD18 signals release of localised Ca2+from intracellular stores in neutrophils.
Immunology
80
,
157
159
Pozzan
T.
,
Lew
D. P.
,
Wollheim
C. B.
,
Tsien
R. Y.
(
1983
).
Is cytosolic calcium regulating neutrophil functions?.
Science
221
,
663
665
Reis
G. A. D.
,
Persechini
P. M.
,
Ribeiro
J. M. C.
,
Oliveira-Castro
G. M.
(
1979
).
Electrophysiology of phagocytic membranes: II. Membrane potential and induction of hyperpolarization in activated macrophages.
Biochim. Biophys. Acta
552
,
331
340
Sawyer
D. W.
,
Sullivan
J. A.
,
Mandell
G. L.
(
1985
).
Intracellular free calcium localized in neutrophils during phagocytosis.
Science
230
,
663
666
Schiffmann
E.
,
Cocoran
B. A.
,
Wahl
S. M.
(
1975
).
N-Formylmethionyl peptides as chemoattractants for leucocytes.
Proc. Nat. Acad. Sci. USA
72
,
1059
1062
Taylor
D. L.
,
Blinks
J. R.
,
Reynolds
G.
(
1980
).
Contractile basis of ameboid movement. VIII. Aequorin luminescence during ameboid movement, endocytosis and capping.
J. Cell Biol
86
,
599
607
Thelen
M.
,
Dewald
B.
,
Baggiolini
M.
(
1993
).
Neutrophils signal transduction and activation of the respiratory burst.
Physiol. Rev.
73
,
797
822
White
J. R.
,
Naccache
P. H.
,
Molski
J. F. P.
,
Borgeat
P.
,
Sha'afi
R. I.
(
1983
).
Direct demonstration of increased concentration of free calcium in rabbit and human neutrophils following stimulation with chemotactic factors.
Biochem. Biophys. Res. Commun
113
,
44
48
Zigmond
S. H.
,
Slonczewski
J. L.
,
White
M. W.
,
Carson
M.
(
1988
).
Polymorphonuclear leukocyte locomotion is insensitive to lowered cytoplasmic calcium levels.
Cell Motil. Cytoskel
9
,
184
189
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