Changes in T .lymphocyte subsets after severe traumatic brain inJury

BACKGROUND： Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE： To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN： A comparative observation. SETTINGS： Department of Neurosurgery, Longgang District Buji People＇s Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS： All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People＇s Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score （GCS） was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group （GCS ranged 14- 15 points）, including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS： （1） The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. （2） The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES： Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS： Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. （1） Changes of T lymphocyte subsets： At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group （t =2.77 - 3.26, P 〈 0.01）, and began to recover at 7 days, which were significantly different from those in the control group （t = 2.06 - 2.24, P 〈 0.05）, and generally recovered to the normal levels at 14 days （P 〉 0.05）. （2） Conditions of pulmonary infections： At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% （22/30）, 0, x2=37.29, P 〈 0.01]. CONCLUSION： Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period （within 7 days）, and they are easily to be accompanied by pulmonary infections.     

A Comparative Study on the Effect of BCG-PSN and Thymopeptides on T-lymphocyte Subsets of Normal and Immunosuppressed Mice

Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c…     

高原地区健康老年人重返平原后外周血T细胞亚群变化的观察

用单克隆抗体测定了移居高原的老年人重返平原后的T细胞亚群的变化结果:①移居西宁(2260m)组、天峻(3000m)组在西宁所测的OKT_3、OKT_4、OKT_8及OKT_4/OKT_8值与在苏州所测的当地老年人无差异。②移居西宁组急返平原后OKT_3、OKT_8水平明显低于返回平原后居住一年以上者(以下简称返回组)(P<0.01～0.001)但OKT_4/OKT_8无差异。③返回组与世居苏州老年人相比,前者OKT_3、OKT_4、OKT_8及OKT_4。OKT_8增高,其中OKT_3、OKT_4增高明显(P<0.01～0.02),作者认为长期移居高原返回平原后T细胞亚群也可能存在一“脱适应”阶段,即机体重新调整重新平衡的一种形式,这一阶段可能需一年以上。     

Thymic stromal cell specialization and the T-cell receptor repertoire

Ten years ago, we proposed a model for thymus function in which thymic epithelial cells are primarily responsible for imprinting major histocompatibility complex (MHC)-restricted specificity, and bone marrow-derived macrophages or dendritic cells are responsible for the induction of self-tolerance. Since then, transgenic and knockout models have allowed for a dissection of thymic stromal components in vivo, leading to a new understanding of their specialized functions. We have determined that with regard to class II-restricted CD4 T-cell development, two distinct subsets of thymic epithelium help shape the repertoire: Cortical epithelium appears solely responsible for positive selection, whereas a fucose-bearing subset of medullary epithelium is specialized for negative selection. This absolute separation of positive and negative selection into two distinct spatial and temporal compartments leads to a much simpler view of the process of repertoire selection. Finally, a novel view of the function of the thymic medulla is discussed.     

休克期大面积切痂对严重烧伤大鼠细胞免疫功能影响的研究

目的 观察休克期大面积切痂对严重烧伤大鼠细胞免疫功能的影响，探索改善烧伤后机体免疫功能紊乱的有效方法。方法 将大鼠分成休克期切痂组（A组）、常规切痂组（B组）和正常对照组（C组）。A、B组造成30％TBSAⅢ度烫伤，C组不烫伤。A组伤后第6h、B组伤后第4d切痂，并于伤后第1、5、9d各活杀10只，取材送检，观察其免疫指标的变化。结果 （1）A、B组与C组比较：A、B组烫伤大鼠各时相点CD3^＋T细胞变化不大（P〉0．05），但CD4^＋T细胞、CD4^＋／CD8^＋比值明显下降、CD8^＋T细胞增高（P〈0．05或P〈0．01）。NK细胞活性明显下降（P〈0．05或P〈0.01），外周血CD25^＋T淋巴细胞表达及经活化后脾脏CD25^＋T淋巴细胞表达明显下降（P〈0．05或P〈0．01）。（2）A组与B组比较：A组CD4^＋T细胞、CD4^＋／CD8^＋比值明显升高、CD8^＋T细胞降低（P〈0．05或P〈0．01），NK细胞活性明显升高（P〈0．05或P〈0．01），外周血CD25^＋T淋巴细胞表达及经活化后脾脏CD25^＋T淋巴细胞表达均明显升高（P〈0．05或P〈0．01）。结论 （1）大鼠烫伤后细胞免疫状况发生了明显变化。（2）休克期切痂可以改善烫伤大鼠T淋巴细胞亚群分布，提高NK细胞活性，增加外周血CD25^＋T淋巴细胞的表达。提高经活化后脾脏CD25^＋T淋巴细胞数。从而改善烫伤大鼠伤后机体的细胞免疫功能。     

A monoclonal antibody (RH1-38) which inhibits multiple systems of cell-mediated cytotoxicity--II. Evidence that the epitope recognized is involved in a late step in the cytolytic mechanism

A monoclonal antibody (RH1-38) which blocks multiple systems of cell-mediated cytotoxicity was functionally characterized. RH1-38 specifically blocks, in the absence of complement, natural killer (NK) activity (K562 targets) without any effect on NK-K562 conjugate formation. Kinetic studies suggested that the antibody blocks a step that occurs 30-120 min after effector populations are mixed with target cells. Single-cell cytotoxicity assays in agarose, combined with standard 51Cr release assays and Michaelis-Menten analysis revealed that RH1-38 markedly decreases Vmax and the number of active NK cells, again without any effect on the number of target-binding cells. The maximum recycling capacity was usually decreased, but in some experiments unchanged, in the presence of the monoclonal antibody. RH1-38 inhibited equally well whole peripheral blood mononuclear leukocytes (PBML), Percoll-fractionated lymphocytes enriched for NK activity, and interferon (IFN)-boosted NK activity. PBML exposed to RH1-38 and then washed mediated depressed NK activity which was partially reversed by subsequent treatment with IFN. These studies are most consistent with the hypothesis that RH1-38 inhibits a step late in the NK cytolytic mechanism rather than through an effect on conjugate formation. The primary effect is probably not on the IFN-generating or boosting mechanism, but a secondary effect on IFN-related mechanisms cannot be ruled out. Inhibition through an effect on a small lymphocyte modulator of NK activity is also unlikely but not rigorously excluded. Thus, RH1-38 appears to inhibit NK activity through a direct effect on NK effector cells, probably by interfering with a cell-surface molecule which is important in the expression of NK activity. The companion paper demonstrates that this monoclonal antibody immunoprecipitates a molecule which is very similar or identical to the LFA-1 antigen. Thus, RH1-38 recognizes either a novel epitope on the LFA-1 molecule or alternatively a distinct, functional killer cell surface molecule. The epitope appears to be involved in a late step in the cytolytic mechanism, possibly part of the effector cell lytic machinery.     

脑出血后的病理改变与T淋巴细胞反应

目的:探讨脑出血血肿周围局部病理改变及细胞免疫机制。方法:用免疫组化方法及组织HE染色法观察20只大鼠尾壳核脑出血24 h,3天、7天血肿周围区域的组织病变及CD3 、CD8 T淋巴细胞的分布形式和表达时程。结果:①在脑出血后24 h血肿周围即可见明显血管源性水肿,大量炎性细胞浸润,以中性粒细胞为主,少量散在淋巴细胞、小胶质细胞、星形细胞、少突胶质细胞弥漫浸润;出血3天、7天以淋巴细胞、巨噬细胞浸润为主,小胶质细胞、星形细胞、少突胶质细胞增生明显,双侧半球皮层下和血管周围出现小胶质细胞结节;②出血灶周围CD3 和CD8 T淋巴细胞浸润在出血后24 h已可见,出血后3天组和出血后7天组,CD3 和CD8 阳性细胞数明显高于出血后24 h组。结论:①脑出血期以中性粒细胞反应为主,以后以淋巴细胞反应为主,胶质细胞反应在出血后24 h已发生,持续一周以上;②CD3 、CD8 阳性细胞的出现提示它们参与了出血后脑损伤的病理过程,在出血7天内, CD3 和CD8-阳性细胞反应呈增强趋势。     

冠心病患者治疗前后血清SOD、ET及T淋巴细胞亚群水平

目的:探讨了冠心病患者治疗前后血清SOD、ET及T淋巴细胞亚群水平。方法:分别应用放免法和单克隆抗体法对42例冠心病患者进行了血清SOD、ET及T淋巴细胞亚群水平检测,并与35名正常健康人作比较。结果:冠心病患者在治疗前血清ET水平显著地高于正常人组(P<0.01),而SOD和CD4/CD8比值明显地低于正常人组(P<0.01),经治疗后一个月则与正常人组比较差异无显著性(P>0.05)。结论:检测冠心病患者血清SOD、ET及T淋巴细胞亚群水平对判断病情及其预后均具有一定的临床实用价值。     

A monoclonal antibody (RH1-38) which inhibits multiple systems of cell-mediated cytotoxicity--I. Identification of a novel epitope on a killer cell surface bimolecular complex important in the cytotoxic response

This paper presents the initial characterization of a mouse monoclonal antibody (RH1-38) which blocks, in the absence of complement, three different systems of cell-mediated cytotoxicity. This monoclonal antibody markedly inhibits cytotoxicity mediated by human natural killer cells, a monocyte-like cell [phorbol myristate acetate (PMA) stimulated HL-60], and cytotoxic T-lymphocytes generated in a mixed leukocyte reaction. RH1-38 is not nonspecifically toxic to cells since antibody-dependent cellular cytotoxicity was not inhibited and viability as assessed by trypan blue exclusion was not affected. Inhibition is specific since control hybridoma culture supernatants, parent (NS-1) ascites supernatant, monoclonal anti-HLA and normal mouse IgG were not significantly inhibitory. In the NK system, the inhibitory effect appears to be due to binding of monoclonal antibody to effector cell surface since exposure of targets to antibody followed by washing yielded no inhibition of killing. Inhibition requires the antigen-binding portion of the antibody molecule and thus appears to be related to steric hindrance of an effector cell surface molecule which is important in the expression of cell-mediated cytotoxicity. Immunoprecipitation of surface-radioiodinated membranes from PMA-stimulated HL-60 cells and analysis on sodium dodecyl sulfate-polyacrylamide gels revealed a bimolecular complex (195,000 and 125,000 daltons) without significant change under reducing conditions. Control immunoprecipitates yielded no peaks of activity. This monoclonal antibody should serve as a useful probe of the function and biochemistry of a killer cell surface antigen important in the expression of cell-mediated cytotoxicity. Since RH1-38 inhibits cytotoxicity mediated by at least three apparently unrelated effector cells, the relevant antigen may be part of a common mechanistic step. As the companion paper demonstrates, this monoclonal antibody does not affect the conjugation step, but appears to block a late step in the NK cytolytic mechanism. Thus, RH1-38 recognizes either an epitope district from previously-described anti-LFA-1 antibodies or alternatively recognizes a distinct functional killer cell surface molecule.