Effects Of IKKβ Mutation On Function And Signal Pathway Of Regulatory B Cells

BACKGROUNDRegulatory B cells(Breg)are B cell subpopulations with immunosuppressive function,which are involved in the maintenance of immune homeostasis and play an important regulatory role in various immunopathological processes.However,there are different subsets of Breg,which still lack the unique marker to distinguish them from the effector B cells,and there are few studies on the related signaling pathways that affect Breg function.IKKβ has important effects on the progression of various diseases such as diabetes and cancer as an important kinase in the NF-κB inflammation signaling pathway.However,it does not only plays an important role in the inflammatory response,but also closely related to the regulatory function of immune cells.IKKβ can affect the expression and function of Treg,and plays an important role in maintaining splenic B cells follicular cells and marginal cells.At present,the effect of IKKβ on regulatory B cell function remains unknown.OBJECTIVEThis study is to observe and analyze the effect of IKKβ kinase activity on Breg function and signal pathway,to explore the signaling mechanism that affects Breg activation,discover new Breg related molecules and signaling pathways,then further explore the relationship between Breg and TKKβ kinase and disease,and provide a theoretical basis for future clinical treatment.METHODSIn the present study,IKKβ mutations and the control mice were used to isolate splenic B cells.Flow cytometry was used to compare the expression of different subpopulations of Breg and its functional molecule IL-10.By co-culturing different B cell subpopulations with T cells,comparing the difference in in vitro inhibitory function.Detecting the inhibition of inflammatory response in vivo by adoptively transfusing Breg cells into C57BL/6 mice.Then discovering new molecules capable of affecting Breg function through transcriptome differential analysis.The results were validated by different means.Finally,new molecules were investigated using antibody blocking methods to detect the effect on Breg function.RESULTS1.The proportion of different Breg subpopulations and the expressions of IL-10 were significantly increased after increase of IKKβ kinase activity.2.The ability of different Breg subpopulations to inhibit T cell proliferation,activation and secretion of inflammatory factors were significantly increased after increase of IKKβ kinase activity.3.Breg could significantly inhibit the inflammatory response in vivo in CHS mice after increase of IKKβ kinase activity.4.The expression of Breg related moleculers such as CD9,CDld,Cr2 and IL-10.Nrp2 were increased in CD9+ Breg after IKKβ mutation through transcriptome analysis.5.The expression of Nrp2 in B cell subsets with regulatory function was significantly increased.Blocking Nrp2 affected Breg to exert its inhibitory function.CONCLUSIONThe proportion,number and expression of IL-10 in different subpopulations of Breg were all increased,and their in vitro and in vivo inhibitory functions were also significantly enhanced after the increase of IKKβ kinase activity.Their functional enhancement may be related to the increase of Nrp2 expression.Studies have revealed that IKKβ is associated with Breg function,which plays an important role in B cell immune regulation.