Study Of The Adjusting Mechanism Of NK92-MI Cell By Norepinephrine

Objective: With the development of society,the change of environment and the accelerating of people life rhythm,stress has become a threat to human health that can not be ignored.Which makes more and more researches focus on neuroendocrine-immune regulation.Norepinephrine is an important neurotransmitters and hormones,and plays an important role in neural signal transduction in the brain.Natural killer cells is one of the important component of the body’s natural immune system.NK cells can be recruited to the sites of inflammation to play anti-infection role under the function of chemokines in infection body.NK cells recognise target cells and non-target cells through the signal of inhibition receptor or activation receptor.NK cells can establish tolerance for autologous cells,recognize and kill allogeneic cells,autologous cells infected by microbiorgnisms or tumor cells.NK cells can destroy target cells with perforin and granzyme,without special sensitization,NK cell play an important role in body anti-infection and anti-tumor process.Cytokines produced by NK cells can interact with other immune cells and produce antigen-specific immune response.NK cells is also a bridge between natural immunity and acquired immunity.NK cell can be as a therapeutic target for autoimmune diseases.At present,researches about the role of NK cells and the changes of the functional of NK cell in the nerve-endocrine-immune network system attract more and more people’s interest.At present,researchers paid little attention to the role of norepinephrine（NE）in the neuro-endocrine-the immune network.Although some literatures shows that NE has certain regulatory role on NK cells,but many mechanisms are not very clear.In this study,we used non-IL-2 dependent cell line NK92-MI as research system,detect NK92-MI cell’s killing rate and the kill-media（perforin and granzyme-B）and IFN-γexpressions,receptor expression,and the regulation of cell function in NK92-MI signal transduction to reveal the internal mechanism of NE on NK cell killing function and regulation.Results: 1.There was a significant difference in the kill rate of NK92-MI cell after treated with NE in a certain concentration range(10^-12～10^-6M)in 4 hours,12 hours,24 hours,36 hours,48 hours（P<0.01）,except 10^-10 M 4h hours（P<0.05）.2.There was a significant difference in the apoptosis rate of NK92-MI cell after treated with NE in a certain concentration range(10^-12～10^-6M)in 4 hours（P<0.01）.3.There was a significant low expression levels of NK92-MI cell killing-media（perforin and granzyme B）after treated with NE（P<0.01 of P<0.05）.The relationship between apoptosis and perforin,granzyme B m RNA expression was negatively correlated.4.There was a significant low expression levels of NK92-MI cell activation receptor（NKp44,NKp46,NKp30,NKG2D）and inhibitory receptors（NKG2A）m RNA after treated with NE in a certain concentration range(10^-12～10^-6M)in 24h（P<0.01）.5.There was a significant low expression levels of NK92-MI cell molecules of the membrane activation receptors（NKp44,NKp46,NKp30,2B4,NKp80,NKG2D）,inhibitory receptors（NKG2A,KIR3DL1）after treated with NE in a certain concentration range(10^-12～10^-6M)in 24hours（P<0.01）.6.There was a significant high kill rate of NK92-MI cell after treated with α receptor antagonist（phentolamine）,β1 receptor antagonist（CGP20712A）,β2receptor antagonist（ICI118551）,PKA inhibitor（Rp-8-Br-c AMP）first and then with NE（P<0.01）.7.There was a significant high expression levels of NK92-MI cell killing-media（perforin and granzyme B）m RNA after treated with α receptor antagonist（phentolamine）,β1 receptor antagonist（CGP20712A）,β2 receptor antagonist（ICI118551）first and then with NE（P<0.01）.8.There was a significant high expression levels of NK92-MI cell activated receptor（NKp44,NKp46,NKp30,NKG2D）and inhibitory receptors（NKG2A）m RNA after treated with α receptor antagonist（phentolamine）,β1receptor antagonist（CGP20712A）,β2 receptor antagonist（ICI118551）first and then with NE.There was a significant high expression levels of NK92-MI celactivated receptor（NKp44,NKp46,NKp30,NKG2D）m RNA with three kind of receptor antagonist,and inhibitory receptors（NKG2A）m RNA with β2 receptor antagonist（ICI118551）（P<0.01）,inhibitory receptors（NKG2A）m RNA with α receptor antagonist（phentolamine）,β1receptor antagonist（CGP20712A）（P<0.05）.9.There was a significant high expression levels of NK92-MI cell killing-media IFN-γ after treated with β2 receptor antagonist（ICI118551）first and then with NE.With 0.1μM β2 receptor antagonist（ICI118551）（P<0.05）and 0.3μM,1.0μM（P<0.01）.10.There was a significant low expression levels of NK92-MI cell intracellular c AMP after treated with β2 receptor antagonist（ICI118551）first and then with NE.With 0.3μM β2 receptor antagonist（ICI118551）（P<0.05）and1.0μM（P<0.01）.11.There was a significant high protein expression levels of NK92-MI cell killing-media（perforin and granzyme B）after treated with β2 receptor antagonist（ICI118551）first and then with NE and low expression levels of CREB and p-CREB.With 0.3μM and 1.0μM β2 receptor antagonist（ICI118551）,there was a significant high protein expression levels of perforin and CREB and p-CREB（P<0.01）.With 0.3μM β2receptor antagonist（ICI118551）,there was a significant high protein expression levels of granzyme B（P<0.05）and 1.0μM（P<0.01）.12.There was a significant high kill rate of NK92-MI cell after treated with PKA inhibitor（Rp-8-Br-c AMP）first and then with NE（P<0.01）.Conclusion: 1.A certain rang concentration of NE inhibit NK92-MI cell killing-medium（perforin and granzyme B）,IFN-γ and killing activated receptors expression level through inducing NK92-MI cell apoptosis to.2.NE regulates the killing activity of NK cells by activating a variety of receptor pathways such as alpha receptor,beta 1 receptor and beta 2 receptor in NK cells at the same time,in which the role of beta 2 receptor is the most significant.3.NE inhibit NK92-MI cell mainly through theβ2-AR/c AMP/PKA/p-CREB signal pathway.