External calcium-dependent, F-actin-independent and pertussis toxin-insensitive novel neutrophil locomotion induced by a mAb.
We previously demonstrated that a mAb to human neutrophils, designated 3H9, which was established by screening for inhibition of neutrophil adherence to plastic plates containing fetal bovine serum, enhanced both n-formyl-methionyl-leucyl-phenylalanine (FMLP)-induced chemotaxis and random migration of neutrophils. In the present study, we examined the mechanisms of 3H9-induced enhancement of neutrophil locomotion in the phagokinetic track assay. 3H9-induced neutrophil locomotion maintained a straight path which was different from the track resulting from FMLP-stimulated locomotion. This 3H9-induced migration required extracellular Ca2+. beta 2-Integrin activation was a prerequisite for the increase in cytosolic free calcium induced by 3H9 treatment. However, stimulation by 3H9 did not induce an increase in F-actin, even after CD18 activation. Signal transduction after molecular recognition by 3H9 was not mediated by pertussis toxin-sensitive, heterotrimeric G proteins. These results suggest that 3H9 enhances neutrophil migration by mechanisms which are different from those involved in usual chemoattractant-induced migration. Neutrophil surface molecules recognized by 3H9 may play a crucial role in the regulation of transendothelial migration of leukocytes.
Suzuki
H
H
Department of Immunology and Parasitology, Yamagata University School of Medicine, Japan.
Takei
H
H
Ohtake
K
K
Watanabe
T
T
Sendo
F
F
D000199:Actins / Q000378:metabolism / Q000494:pharmacology*; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D018821:CD18 Antigens / Q000502:physiology; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology*; D002465:Cell Movement / Q000187:drug effects / Q000276:immunology*; D006801:Humans; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D037342:Pertussis Toxin; D011108:Polymers / Q000378:metabolism; D012680:Sensitivity and Specificity; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
D000199:Actins; D000911:Antibodies, Monoclonal; D018821:CD18 Antigens; D011108:Polymers; D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin; D002118:Calcium