Determination To The Level Of Interleukin And Lymphocyte Subsets In The Bronchoalveolar Lavage Fluid Of The Patients With Sarcoidosis And Extrinsic Allergic Alveolitis

PrefaceThe incidence rate of interstitial lung disease(ILD)increases unceasingly,which has become an important kind of disease threatening human health.SAR,EAA is 2 kinds of comparatively important interstitial lung disease,and its pathogenesis is not completely clear at present,but more and more researches show that cytokine especial inflammatory factor maybe act much importance to the occurrence and development of diseases.Interleukin(IL)is an important inflammatory monocytic factor acting to multiple target cells.IL-4 different to IL-2 is belonged to another type of cytokine.It is thought highly that the proportional disequilibrium of Th1 and Th2 cytokine which may cause the ILD.The idea of this research is expected to realized more completely to the pathogenesis of SAR and EAA through discussing the action of IL-4 and IL-2 to the process of the diseases and their clinical significance.Experimental MaterialInvestigated Objection(l)SAR group:24 patients with SAR,no other interstitial lung disease,through clinical examination,pulmonary function test,blood gas analysis, pulmonary high resolution computerized tomography(HRCT),trans-branchioalveolar douche(BAL)and transbronchial lung biopsy(TBLB).The diagnosis of these patients is in line with non-traumatic standard suggested by both American Thoracic Science(ATS) and Europe Respiration Science(ERS).Before the examination,all the patients are not treated by glucocorticoid hormone and other immuno-suppressive drugs.(2)EAA group: 24 patients with EAA,no other interstitial lung disease,through clinical examination, pulmonary function test,blood gas analysis,pulmonary high resolution computerized tomography(HRCT),trans-branchioalveolar douche(BAL)and transbronchial lung biopsy(TBLB).The diagnosis of these patients is in line with non-traumatic standard suggested by both American Thoracic Science(ATS)and Europe Respiration Science(ERS).Before the examination,all the patients are not treated by glucocorticoid hormone and other immuno-supp-ressive drugs.Experimental instrument:Olympus 260 fibrobronchos-cope,Universal 32R centrifugal apparatus,BIO-RAD enzy-me-labelled meter.Experimental reagent:IL-4 and IL-2 Test Kit are both bought from shanghai JITAI Biology Medicine Company.Experimental Mathod1.Bronchoalveolar lavage is performed by Olympus 260 electron bronchoscope with 5.9mm bore,and then get 3ml venous blood from the elbow immediately.2.BLAF is filtrated by 12 layers carbasus,and then injected into the plastic centrifuge tube disinfected through high pressure.After centrifugated,it is put into sterile dialysis sacke,then soaked in the polyethylene glycol solutions.After 24 hours, Saline is added in(l/10 amount of the BALF),then take the concentration fluid,which is coverde cryopreservatively and reserved.when examination,the supermatant is just taked to estmate the level of IL-4 and IL-2 Centrifugating the venous blood,the supernatant is taked and cryopreservated.3.The level of IL-4 and IL-2 in the blood serum and BALF is estimated through enzyme-linked immunosorbent assay(ELISA)4.Statistic treatment:All the data is indicated as the form of x±s,and t-check is performed.Experiment ResultThe level of IL-4 of the blood serum in the EAA group is higher than in the SAR group.The level of IL-2 of the blood serum in the SAR group was positive correlated with the percentage of neutrophil in the BALF.The level of IL-4 of the BALF in the EAA group was positive correlated with the percentage of macrophage.DiscussionAlthough the pathogenesis of ILD is not completely clear at present,re-cently researchers comprehend the pathogenesis of ILD wider and deeper.Re-search shows that cytokine particularly inflammatory factors maybe act much importance to the occurrence and development of the disease induced by some etiological factors.Now there are more than 20 kinds of cytokine proved to be related to ILD,among them, interleukin is a much important kind of inflammatory mono-cytokine which can influence multiple target cells.IL-4 is a characteristic kind of Th2 cytokine,IL-2 is a important kind of Th1 cytokine.It is thought highly that the proportional disequilibrium of Th1 and Th2 cytokine which may cause the pulmonary fibrosis.The aim of this research is expected to realized more completely to the pathogenesis of ILD through discussing the action of IL-4 and IL-2 to the process of the disease and their clinical significance.Research shows that cytokine such as IL-4,coming from Th2,can enlarge the inflammatory reaction which make the lung structure remodeled,stimulate lung fibroblast hyperplasia with collagen and cellulose deposition increased to lead to basilar membrane of the alveolar wall thickening and diffuse infra-ep-ithelial fibrosis, Research finds that IL-4 is expressed highly in injured alveo-lar epithelial cells,IL-4 is chemokine of fibroblast,which can induce fibroblast to proliferate,increase generation of the extra-cellular collagen,and accelerate the fibrosis through anti-apoptosis. Our outcome shows that the level of IL-4 in the blood serum of SAR group is Lower than EAA group..IL-2 can cause inflammation and attend to immunol-oregulation,produced by activated macrophage,dendrite cell and neutrophil.IL-2 is essential cytokine to Th2 cell growing,and play important role in subgroup differentiation of Th2 cell.IL-2 may make Th1 cell proliferate and differentiate to develop Th1 cytokine,but inhibit Th2 cell.IL-2 may induce activated T cell and NK cell to excrete IFN-r and TNF.The level of IL-4 in the BALF of SAR patients is no obvious different to in the BALF of EAA people,but which in the blood serum is lower than EAA people (p＜0.01).This phenomena illus trate that the change of IL-2 is local but not systemic reaction for ILD patients,meanwhile,it suggests partly that IL-2 can inhibit fibroblast to proliferate and fibrous tissue tissue to generate.Above all,more and more evidence make clear that the proportional disequilibrium of Th1 and Th2 cytokine play important role in the process of ILD,which can lead to alveolar inflammatory injury and plerosis.)Conclusion1.The proportional disequilibrium of Th1 and Th2 cytokine play important role in the process of ILD,which can lead to alveolar inflammatory injury and plerosis.2.For SAR patients,change of cytokine IL-2 is local pulmonary reaction,but change of IL-4 is systemic.