[Histamine release properties of human basophils in response to various stimuli].
OBJECTIVE
To investigate the effects of protease activated receptor-2 (PAR-2) agonist, heparin and other stimuli on histamine release from human basophils.


METHODS
Peripheral blood mononuclear cells (PBMCs) were separated by density gradient centrifugation. The PBMCs were then resuspended in complete Hank's balanced salt solution (HBSS) and challenged with various stimulating agents. Histamine level in samples was determined by ELISA.


RESULTS
10 mg/L trypsin could induce histamine release from basophils. However, its stimulatory effect on basophils was weaker than that of anti-IgE, calcium ionophore (CI), F-Met-Leu-Phe (FMLP), C5a and substance P. PAR-2 agonist SLIGKV-NH(2) failed to activate basophils. Heparin, C5 and adenosine did not induce any histamine release at concentrations tested, but heparin enhanced histamine release induced by C5a and substance P.


CONCLUSIONS
Trypsin, anti-IgE, CI, FMLP, C5a and substance P can induce histamine release from baosophils, but PAR-2 agonist can not. Heparin can greatly enhance the ability of C5a and substance P to stimulate histamine release, which may be a novel mechanism of amplification of basophil activation signal.
Allergy and Inflammation Research Institute, Medical College, Shantou University, Shantou 515031, China.
Wei
W
Zhu
Shao-heng
SH
He
Zi-xia
ZX
Lin
Yi-ling
YL
Fu
D000818:Animals; D001491:Basophils / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism*; D006493:Heparin / Q000494:pharmacology; D006636:Histamine Release / Q000187:drug effects* / Q000276:immunology; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology
D006493:Heparin