Experimental Study On The Related Immunoregulation Function Of Dendritic Cell In Peripheral Blood With Acitretin

Objective：Dendritic cells (DCs) are specialized antigen presenting cell(APCs) that bridge innate and adaptive immunity in mammals. These cells arethe only APCs that activate the" initial" immune response and stimulate theproliferation of T lymphocytes. They play an important role in initiated theimmune responses and immune regulation.Retinoids (retinoc acid, RA) are the derivatives of the natural and syntheticvitamin A, including a variety of isomers. Such as13CIS retinoic acid(13-cis-retinoic acid,13-cRA), all-trans retinoic acid (all-trans retinoic,ATRA),9CIS retinoic acid (9-cis-retinoic acid,9-cRA) and also.They areable to influence the proliferation, growth and differentiation of epithelial cells,to regulation morphological changes of a variety of cells and to participateapoptosis of cells. Other, they act on the sebaceous glands and influencedifferentiation of sebaceous gland epithelial cell in vitro. So they are effectivetherapeutic and chemopreventive agents for some skin diseases. In recentyears some research found that they have a very strong immunomodulatoryrole. Acitretin as the second generation of retinoic acid drug, chemical name isall trans-9-(4-methoxy-2,3,6-three methyl phenyl)-3,7-two methyl2,4,6,8-four main clinical azelaic acid, are used in the treatment of variousskin diseases such as psoriasis, keratotic skin disease.we have done a preliminary study about the effect of Acitretin on thedendritic cells from the peripheral blood of nomal human. Aim is the explorewhether the mechanism of regulation human immune system includingobserved the morphology of dendritic cells, test the surface markersCD83, CD86of DCs by FCM and the expression of IL-12by ELISA and thecapability of DC s to stimulate the proliferation of T lymphocytes byallogeneic mixed lymphocyte reaction. They can provide experimental results for the treatment of autoimmune diseases.Methods:1Cell CultureThe peripheral blood mononucleae cells (PBMCs)from10healthypeoples were isolated and cultured in RPMI-1640medium supplemented with15%FCS and in presence of rhIL-4and rhGM-CSF in a atmosphere5%CO2at37℃for7days. The RPMI-1640medium supplemented with15%FCS,100u/ml penicillin and100u/ml streptomycin.2The surface marker CD83of DCs were assayed by FCM.The DCs were divided in three groups, including control group,and twodosing groups treated with acitretin of different concentration respectively. Atthe desired time after treatment the surface markers of CD83in differentgroups was detected by FCM.3The surface marker CD86of DCs were assayed by FCM.The DCs were divided in three groups, including control group,and twodosing groups treated with acitretin of different concentration respectively.Atthe desired time after treatment the surface markers of CD86in differentgroups was detected by FCM.4The morphological changes of DCs were observed by the reversemicroscopy after the treatment of different groups.5Effects of different concentration of acitretin on the the secretedproduction of IL-12by DCs at12hours were measured by ELISA.The DCs were divided in three groups, incluing control group, and twodosing groups treated with acitretin of different concentration respectively. Atthe desired time after treatment the content of IL-12in cell culturesupernatantwas detected by ELISA.6The capability of DC to stimulate the proliferation of T lymphocytes wasevaluated by allogeneic mixed lymphocyte reaction.The proliferation capacities of allogeneic mixed lymphocytes treated witheach group cells were detected by MTT.7Statistic analysis: Data wre analyzed by spss13.0for windows, using paired-samples t-test,with significance of difference standard a=0.05.Results:1To detect the changes of surface markers CD83of DCs in different groupsby FCM.The expreesion of the surface markers CD83of DCs in the acitretin groupsafter12hours were significantly higher than the control group.The volume ofCD83in the three groups were42.55±10.58,52.93±12.87,59.80±12.47respectively. There has significantly difference among the acitretin groups (p＜0.05)2To detect the changes of surface markers CD86of DCs in different groupsby FCM.The expreesion of the surface markers CD86of DC in the acitretin groupsafter12hours were significantly higher than that in the control group.Thevolume of CD86in the three groups were42.55±10.58,52.93±12.87,59.80±12.47respectively. There were significant difference between theacitretin groups.(p＜0.05)3To observe the morphology of DC by the reverse microscopy.Control group：DCs morphological inregular,a few cells growth withadherence,most cells growth with suspension; To observe the morphology ofDCs by the reverse microscopy. Before the each group of cells treated withacitretin for12hours, the cells growth with adherence were reduced and thecells growth with suspension were increased, And with the increase of theconcentration of acitretin the phenomenon of growth with suspension wasmore obviously.4To detect the production of IL-12secreted by DCs with ELISAThe expreesion of the production of IL-12secreted by DCs in the acitretingroups after12hours were significantly higher than that in the controlgroup.The secretory volume of IL-12in the three groups were57.49±10.63,67.24±10.55,72.89±10.18respectively. There has significantlydifference among the acitretin groups(p＜0.05).5The proliferation capacities of allogeneic mixed lymphocytes stimulated by each cells of group were detected by MTT.The proliferation capacities of allogeneic mixed lymphocytes were higer inthe acitretin groups than in the control group (p﹤0.05),but there were nosignificant differences between the acitretin groups.Conclusion:1Acitretin is able to significantly stimulate the expression of CD83andCD86of DCs.2Acitretin can enhanced the proliferation capacity of allogeneic mixedlymphocytes.3Acitretin can significantly promote the secrected production of IL-12byDCs.4Acitretin can improve the ability of DCs introduced antigen presenting andpromote DCs differentiation into mature.