Effects of nickel on eosinophil survival.
BACKGROUND
Accessories, watches, coins and other items containing metal sometimes cause contact dermatitis and metal allergy. Among metals, nickel in alloys is ionized by sweat on the surface of the skin and exhibits particularly marked irritancy and allergenicity. Although eosinophils play important roles in allergy, the effects of nickel on eosinophils have not been elucidated.


METHODS
Eosinophils were prepared from the peritoneal cavity in rats immunized with Ascaris suum extract. Purified rat eosinophils were incubated in the presence of various kinds of metals including nickel. The viability of eosinophils was analyzed using a flow cytometer.


RESULTS
When rat eosinophils were incubated for 3 days in the presence of nickel chloride at 30-1,000 microM, the viability of eosinophils was decreased in a concentration-dependent manner. Nickel chloride at 300 muM significantly increased the percentage of annexin V+ PI- eosinophils. The population of annexin V+ PI- eosinophils was also increased by nickel sulfate, cobalt chloride and zinc sulfate. The binding of nickel ions to eosinophils was detected by flow cytometer.


CONCLUSIONS
Nickel ions bind to eosinophils and decrease the viability of eosinophils through the induction of apoptosis. Nickel ions may exhibit activity which modifies the function of eosinophils in allergy.
Ishihara
Kenji
K
Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512, Japan. ishihara@mx.ibaraki.ac.jp
Goi
Yoshiaki
Y
Hong
Jang Ja
JJ
Seyama
Toshio
T
Ohtsu
Hiroshi
H
Wada
Hiroshi
H
Ohuchi
Kazuo
K
Hirasawa
Noriyasu
N
D000818:Animals; D017209:Apoptosis; D001249:Asthma / Q000139:chemically induced / Q000276:immunology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004804:Eosinophils / Q000187:drug effects* / Q000276:immunology; D009532:Nickel / Q000276:immunology / Q000494:pharmacology*; D051381:Rats
C022838:nickel chloride; D009532:Nickel