Effects Of Titanium Ions On KCa3.1 Channel Of Jurkat T Lymphocytes

OBJECTIVE:To observe the expression of KCa3,1 channels after Titanium ions effects of T lymphocytes and the changes of cell membrane potential and intracellular calcium ion before and after blocking KCa3.1 channels,and investigated the possible mechanism of KCa3.1 channel in the activation of T lymphocytes by titanium ions.METHODS:1.Jurkat T lymphocytes were cultured in vitro and pre-activated with phytohemagglutinin（PHA）.The CCK8 method was used to examine the effect of different concentrations of titanium ions on the proliferation of activated T lymphocytes.2.Jurkat T lymphocytes were cultured in vitro with or without phytohemagglutinin（PHA）pre-stimulation and exposed to 0μmol/L、25μmol/L、50μmol/L and 100μmol/L titanium ions for 12h.Real-time PCR was used to detect the expression of KCa3.1 channel.Flow cytometry was used to detect the changes of membrane potential and calcium concentration of Jurkat T lymphocytes before and after TRAM-34 was blocked.RESULTS:1.titanium ions increased the value of pre-activated Jurkat T lymphocytes with increasing titanium ion concentration.（P<0.05）.2.25μmol/L,50μmol/L,100μmol/L titanium ions were cultured for 12hours with PHA（-）Jurkat T lymphocytes.There was not statistically significant at KCa3.1mRANA expression on 25μmol/L,50μmol/L,100μmol/L titanium ions（P﹥0.05）.25μmol/L,50μmol/L,100μmol/L titanium ions were cultured for12 hours with PHA（+）Jurkat T lymphocytes.There was statistically significant at KCa3.1mRANA expression on 25μmol/L,50μmol/L,100μmol/L titanium ions（P﹤0.05）.3.The difference of membrane potential was not statistically significant compared with control group in 50μmol/L titanium ions group after KCa3.1channel was blocked（P>0.05）,and there was statistically significant of membrane potential between pre-blocked group and non-blocked group（P﹤0.05）.The membrane potential of 50μmol/L titanium ions pre-activated T lymphocyte group was significantly significant compared with control group（P<0.05）.The comparison between TRAM-34（+）and TRAM-34（-）groups was statisticallysignificant（P<0.05）.ThedifferenceofintracellularCa²⁺concentration was statistically significant compared with control group in50μmol/L titanium ions group after KCa3.1 channel was blocked（P﹤0.05）,and there was not significant of intracellular Ca²⁺concentration between pre-blocked group and non-blocked group（P>0.05）.The intracellular Ca²⁺concentration of 50μmol/L titanium ions pre-activated T lymphocyte group was significantly significant compared with control group（P<0.05）.The comparison between TRAM-34（+）and TRAM-34（-）groups was statistically significant（P<0.05）.CONCLUSIONS:1.Titanium ions within 100μmol/L can increase the proliferation of activated Jurkat T lymphocytes.2.Titanium ions can cause changes in Jurkat T lymphocytes in the expression of KCa3.1 channels.3.The KCa3.1 channel can regulate the calcium ion concentration and membrane potential of activated Jurkat T cells to a certain extent.