The Ectopic Expression Of LTBR On The SLE's Peripheral Monocyte And It's Mechanism Explore

systemic lupus eythematosus is one typal of many Autogenous immunological diseases, the patients appear many choas of cell regulations, impairment of cell functionals, and the cytokines secrtion are also abnormal, its pathogenesy is not clear so far althougt many research have proceeded, reflect it is a complicated disease. The monocyte have multiple functions in our bodies such as defend infections ,regulate inflammation and induce immunity. After enter the blood stream as quiescent cell, circulating monocyte differentiate further into resident tissue macrophages and this proceed aquired specialized local microenviroment. In some enviroenment, the monocyte also differentiate into dendritic cells. One hallmark character of the monocyte and macrophage systerm is that this systerm have a phagocytosis and subsequent antigen presentation function. In Eightes of last centray there have some scholar raise the hypothesis that the monocyte and macrophage systerm have a defect in phagocytosis in the SLE thus lead accumulation of the apoptotic body and trigger the autoimmune response. Recent studies, however,exploring mainly lupus nephritis suggest an active role of Monocyte/Macrophage in mediating tissue inflammation and injury. So, we think the monocyte and macrophage systerm play an more important role in the pathogenesis of SLE. Moreover, rencent study have find in lupus mouse modle there have high level CXCL13,-one of checkcyte-,which major source is CD11positive macrophages. And early studise have revealed CXCL13 is the LTBR's taget gene. For these reason, we suspect there may be have ectopic expression of LTBR on the surface of monocyte in peripheral blood, if ,it may be have some influence on the SLE'pathogenesis proceed . with regards to this, our study team collected some samples of SLE patients, separate its PBMC in order to detect and analysis its phenotype. Meanwhile, for further explore the mechanism of regulation the expression of LTBR on the surface of monocyte, we use some irritant todo stimulation experiment on the monocyte cell-line. First of all, we obtained SLE and normal volunteer's PBMC by density gradient Centrifugation, then detect the expression level of LTBR on the surface of monocyte use immunofluorescence conjunct antibody. following, we use immunomagnetic beads positive selecte the monocyte and then cultivated the monocyte which source from normal volunteer. In the proceed of cultivate, addition LPS,PMA and dexamethasone to the systerm as irritant. We in order to investigate whether these irritant have some effect on the expression regulation of LTBR. We also detect the mRNA level of LTBR in the monocyte which come from SLE patients and normal volunteer by the method of RT-PCR. When the irritant were added into normal peripheral monocyte cultivate systerm., the same detect were proceed use RT-PCR. Besides,in order to understader more about the mechanism of regulation of the expression of LTBR, we use two kinds LTBR positive monocyte cell-line to study further. This two kinds cell-line were U937 and THP1 monocyte cell-lines, they are both un maturate cells which come from leukemia patients. we added LPS,PMA or dexamethasone to these two cell-lines cultivate systerm. Then We detect the mRNA level and pretain level of LTBR use RT-PCR and FACS respectively.The results of our study indicate that no LTBR was expreeion on the normal peripheral monocyte, which is coincidence with earler study. But to our supprise, LTBR is expression on the SLE's peripheral monocyte, and its expression is at a high level. This result was identified both on mRNA level and pretain level. normal peripheral monocyte still don't express the LTBR moleculer after added LPS, PMA or dexamethasone to its cultivate systerm. These phenomenon demonstrate that the LTBR ectopic expression on the SLE's peripheral monocyte maybe have a more deliplicate reason besides the monocyte activity status. But when we use the monocye cell-line—U937 and THP1, the results were diferent with normal peripheral monocyte, we find with the U937 cell-line, the dexamethasone can elevate the LTBR moleculer expression, while the LPS have no effect on LTBR expression on shis type cell. Interestingly, with the more matuant cell-line—THP1, neither dexamethasone nor LPS have effect on LTBR expression. This phenomenon more like normal peripheral monocyte . these results suggeste us that the expresse regulation of LTBR maybe differrent to same irritant ,dicided by the different growth status. At last but not lest, use PMA stimulate the two monocyte cell-lines, we find the LTBR moleculer appear similar reaction to this irrition. this is a unexpect result because at mRNA level there was not LTBR expression decrease but at pretain level its expression was decrease. The mechanism of this paradox phenomenon we don't explore in our study for some reason. to summarize our study, we find the LTBR moleculer have a ectopic expression on the SLE's peripheral monocyte, this ectopic expression is not simply induced by activity of monocyte or used glucocorticoid in the therapy. On the explore regulation of LTBR moleculer express with normal volunteer peripheral monocyte and two unmatuant monocyte cell-line, we find that LTBR is a regulable moleculer in some way, but this regulation meybe depended on the growth status of the cell.