人血白细胞黏附分子表达及黏附能力与辐射剂量的关系

目的观察人离体外周血白细胞^60Coγ射线照射后24h内黏附分子的表达及单个核细胞黏附功能与照射剂量间的关系。方法人外周静脉血经0、2、4和6Gy γ射线照射后，用流式细胞术检测照后0、6、12和24h不同黏附分子（CD11a、CD11b、CD18、CD29、CD49d、CD54）的表达。用细胞黏附方法测定照后6、12和24h单个核细胞对不同底物的黏附情况。结果粒细胞、单核细胞CD29的表达在照后6h，2和4Gy组升高，在其他时间点各剂量照射组表现为下降；单个核细胞对底物IgG的黏附能力在照后6、12和24h的各个剂量组均表现为增强。结论外周血细胞黏附分子表达和黏附能力与照射剂量具有较好的量效关系。     

大鼠γ线照射后单个核细胞的黏附及迁移功能研究

细胞黏附分子（cell adhesion molecules，CAMs）为一类调节细胞与细胞间、细胞与细胞外基质间相互结合和起黏附作用的糖蛋白，在胚胎发育和分化、炎性反应和创伤愈合免疫应答、肿瘤扩散与转移等许多生理和病理过程中发挥重要生物学功能。近年来的研究表明，肿瘤患者在接受一定剂量的放疗后，血液及肿瘤周围组织CAMs表达及其介导的黏附功能发生改变，这种改变与照射剂量存在良好的量效关系。这些     

人参皂苷Re对肿瘤坏死因子-α诱导的白细胞活化的抑制作用及机制

目的研究人参皂苷Re对肿瘤坏死因子-α诱导的白细胞活化的作用及其机制。方法提取并培养人外周血中性白细胞,用酶标仪和流式细胞仪体外观察肿瘤坏死因子-α(20 ng/ml)对中性白细胞黏附相关指标MPO的分泌以及白细胞表面黏附分子CD11b和CD18的表达的诱导作用,同时观察肿瘤坏死因子-α(20 ng/ml)对中性白细胞跨内皮细胞迁移的诱导作用,并测定不同浓度人参皂苷Re对以上变化的影响。结果人参皂苷Re可以剂量依赖性地明显抑制肿瘤坏死因子-α诱导的黏附于内皮细胞表面白细胞MPO的分泌和黏附分子CD11b、CD18的表达,明显抑制肿瘤坏死因子-α诱导的中性白细胞跨内皮细胞的迁移。结论人参皂苷Re可以抑制由肿瘤坏死因子-α诱导的白细胞的活化,包括白细胞与内皮细胞的黏附和游出,该作用与抑制白细胞表面黏附分子CD11b和CD18的表达相关。     

血透对尿毒症患者外周血中性粒细胞黏附分子表达的影响

 目的 观察血透时外周血中性粒细胞黏附分子(cell adhesion molecules, CAMs)CD62L、CD11a、CD11b、CD54表达的变化规律,以及不同透析膜对上述细胞黏附分子表达的影响.方法 实验分为血透组和健康对照组,同时血透组又分为铜仿膜组和聚砜膜组;流式细胞仪检测各组外周血中性粒细胞黏附分子CD62L、CD11a、CD11b、CD54的表达.结果 血透组中性粒细胞CD11b表达明显升高,CD62L和CD54表达明显降低;透析不久后,可见2透析组CD11b表达明显上调,CD62L和CD54表达下调.透析结束时CD11b、CD62L及CD54恢复透析前水平;CD11a变化不明显;铜仿膜组CD11b表达较聚砜膜组明显上调(P<0.05).结论 维持性血透可影响中性粒细胞的活性,使细胞表面黏附分子的表达发生规律变化,从而影响尿毒症患者的免疫力,可能增加了感染的机会.黏附分子表达与使用的透析膜的生物相容性相关.     

芍药苷对辐射内皮细胞起保护作用的机制

目的观察芍药苷对辐射损伤内皮细胞保护作用的分子机制。方法 10Gy60Coγ照射前1h给予内皮细胞芍药苷,采用逆转录聚合酶链反应、免疫组化以及免疫印迹等方法检测细胞间黏附分子1、血管细胞黏附分子1的表达。结果人脐静脉内皮细胞经10Gy60Coγ照射后与正常组细胞相比,活性氧,丙二醛水平明显上升,谷胱甘肽,超氧化物歧化酶水平明显降低,黏附分子mRNA与蛋白的表达明显升高;随着芍药苷给药浓度的变化,加药组细胞中活性氧,丙二醛水平逐渐降低,谷胱甘肽,超氧化物歧化酶水平逐渐升高;免疫组化的结果显示芍药苷可降低辐射引起的黏附分子的表达,逆转录聚合酶链式反应检测显示芍药苷可降低辐射引起的黏附分子的mRNA的表达,Westernblot检测显示芍药苷可降低辐射引起的黏附分子的蛋白表达水平。分子信号通路的研究表明,芍药苷通过影响JNK通路进一步抑制激活物蛋白1与目的基因的结合。结论芍药苷通过抑制JNK细胞核激酶-激活物蛋白通路进而抑制黏附分子表达,这可能是芍药苷对辐射损伤内皮细胞保护作用的分子机制。     

细胞粘附分子的电离辐射效应研究进展

细胞粘附分子是调节细胞间及细胞与细胞外基质相互作用的一类膜型或跨膜糖蛋白，其作用涉及细胞的粘附、迁移、分化和信号转导。正常组织或肿瘤组织受电离辐射后会导致细胞粘附分子表达的改变。照射方式不同，受照组织不同，粘附分子的表达也不同，有些粘附分子的表达与受照剂量存在良好的量效关系。受照后，粘附分子的改变具有作为一种新的辐射生物剂量仪的潜能。     

细胞粘附分子的电离辐射效应研究进展

细胞粘附分子是调节细胞间及细胞与细胞外基质相互作用的一类膜型或跨膜糖蛋白,其作用涉及细胞的粘附、迁移、分化和信号转导。正常组织或肿瘤组织受电离辐射后会导致细胞粘附分子表达的改变。照射方式不同,受照组织不同,粘附分子的表达也不同,有些粘附分子的表达与受照剂量存在良好的量效关系。受照后,粘附分子的改变具有作为一种新的辐射生物剂量仪的潜能。     

当归注射液对辐射损伤小鼠骨髓细胞黏附分子表达及增殖周期的影响

目的探讨当归注射液对辐射损伤小鼠骨髓有核细胞黏附分子表达及增殖周期的影响。方法BALB/c小鼠随机分为3组:正常组、照射组和当归注射液预防组。正常组:即未经照射组。照射组:于照射前3d起给予10ml·kg-1·d-1无菌生理盐水腹腔注射。当归注射液预防组:于照射前3d起给予腹腔注射当归注射液2·5g·kg-1·d-1。于照射后第7天断颈处死小鼠,取出股骨,计数骨髓单个核细胞。经流式细胞仪分别检测骨髓单个核细胞黏附分子CD49d和CD49e及G0/G1期细胞百分率和周期蛋白D2表达水平。结果与正常组比较,照射组造血细胞明显减少,骨髓有核细胞黏附分子CD49d和CD49e表达明显下降,G0/G1期细胞百分率明显增加,而细胞周期蛋白D2表达水平明显降低,当归注射液预防组能增加骨髓单个核细胞计数,明显提高细胞黏附分子CD49d和CD49e的表达,降低G0/G1期细胞百分率,提高细胞周期蛋白D2的表达水平。结论当归注射液能通过提高细胞黏附分子表达水平,刺激细胞周期蛋白D2的表达促进造血细胞的增殖。     

辐射对EL-4、J774A.1细胞CD2、CD48表达的影响

目的　通过时程及量效研究观察不同剂量X射线照射对EL 4和J774A 1细胞株中表面分子CD2、CD4 8的影响。方法　采用荧光免疫流式细胞术检测蛋白表达的变化。结果　 (1)EL 4细胞CD2分子表达结果显示 ,0 0 75GyX射线照射后CD2合成在照射后 4h即开始升高 ,至 8～ 16h达峰值 (P <0 0 5～ 0 0 1) ,2Gy照射后则从照射后 4h开始下降 ,至 8h达最低点 (P <0 0 1) ,一直持续较低至 4 8h恢复 ;8h量效结果显示 ,在低剂量区 0 0 5 0 ,0 0 75Gy使CD2表达上调 ,而高剂量范围中 1,2Gy使CD2表达下调。 (2 )J774A 1细胞CD4 8分子表达结果显示 ,0 0 75GyX射线照射后CD4 8合成在照射后 2h即开始升高 ,至 4h达峰值 (P <0 0 5 ) ,随后急剧下降 ,8h恢复至假照射水平 ,16～4 8h下降明显低于假照射水平 (P <0 0 5 ) ,2Gy照射后则从照射后 2h开始下降 ,至 8h达最低点(P <0 0 1) ,随后有所恢复 ,但直至 4 8h仍未能恢复至假照射水平。 4h量效结果显示 ,在低剂量区0 0 5 0 ,0 0 75 ,0 10 0Gy使CD4 8表达上调 ,而高剂量范围中 1～ 6Gy均使CD4 8表达下调 (P <0 0 5～0 0 1)。结论　X射线照射可引起CD2、CD4 8不同的辐射效应 ,两者的相互作用体现出低剂量辐射具有不同于高剂量辐射的兴奋效应。     

用荧光原位杂交技术建立~(60)Coγ射线诱发人外周血淋巴细胞染色体易位率剂量效应曲线及易位的持续性研究

目的　研究不同剂量6 0 Coγ射线诱发人外周血淋巴细胞染色体易位率和辐射剂量间的剂量效应关系以及观察易位率在同一剂量、不同时相点的变化。方法　采用荧光原位杂交技术和连续Giemsa法 ,用 4号和 7号全染色体探针分析 0、0 2 5、0 5、0 75、1和 2Gy6 0 Coγ射线离体照射诱发人外周血淋巴细胞染色体易位率 ,同时对两个剂量点进行 5 2和 72h培养 ,比较其易位率。结果　易位率和辐射剂量间的量效关系可以用一个二次多项式方程Y =0 0 0 30 0 0 134D 0 0 16 5D2 来描述 ;易位率在 5 2和 72h培养时差异无显著性。结论　易位率和辐射剂量间存在良好的量效关系 ,可作为进行早先照射剂量重建的理论依据     

UVB-irradiated T-cells undergoing apoptosis lose L-selectin by metalloprotease-mediated shedding

Abstract. Purpose : L-selectin (CD62L) is a prerequisite for leucocyte adhesion to endothelial cells of blood vessels and consequently for transmigration. Its expression on the cell surface therefore regulates the ability of lymphocytes to enter lymph nodes, to re-enter blood vessels or to invade tissues at sites of inflammation. The aim of this study was to determine the expression of CD62L on apoptotic lymphocytes after UVB irradiation. Materials and methods : Peripheral blood mononuclear cells (PBMC) were isolated from peripheral blood of normal healthy volunteers. Cells were stimulated with phorbol myristate acetate (PMA) and ionomycin for activation. Apoptosis in peripheral T-cells and Jurkat cells was induced by irradiation with UVB (120 mJ/cm2). In addition, T-cells or Jurkat cells were cultured for the indicated time with anti-Fas antibody CH11. The CH11-induced apoptosis was inhibited by the pan-caspase inhibitor zVAD-fmk. For detection of apoptosis, cells were analysed by cytofluorometry for morphological changes typical for apoptosis. The reliability of the apoptotic cell gate was confirmed by staining with FITClabelled annexin-V in the presence of propidium iodide (PI). For FACS analysis of CD62L expression on the cell-surface immunofluorescence was performed using FITC-conjugated anti-CD62L and PE-conjugated anti-CD3 antibodies. Soluble CD62L (sCD62L) in the cell supernatants was measured by standard ELISA technique. Assays were performed in the presence and absence of metalloprotease inhibitor KB8301. Results : PBMC from healthy volunteers undergoing apoptosis following UVB irradiation selectively shed CD62L, whereas the expression of the lineage-specific marker CD3 showed only minor changes. Shedding was blocked by the hydroxamic acid-based metalloprotease inhibitor KB8301. When Jurkat cells were treated with the caspase inhibitor zVAD-fmk, anti-CD95 antibodies did not induce apoptosis, and the expression of CD62L remained unaltered. Conclusion : UVB or ionizing radiation induce apoptosis in lymphocytes. The loss of CD62L is associated with apoptosis and will influence lymphocyte tra Ýcking and, by excluding them from CD62L-mediated adhesion and tissue invasion, might contribute to the regulation of inflammation.     

UVB-irradiated T-cells undergoing apoptosis lose L-selectin by metalloprotese-mediated shedding

PURPOSE: L-selectin (CD62L) is a prerequisite for leucocyte adhesion to endothelial cells of blood vessels and consequently for transmigration. Its expression on the cell surface therefore regulates the ability of lymphocytes to enter lymph nodes, to re-enter blood vessels or to invade tissues at sites of inflammation. The aim of this study was to determine the expression of CD62L on apoptotic lymphocytes after UVB irradiation. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from peripheral blood of normal healthy volunteers. Cells were stimulated with phorbol myristate acetate (PMA) and ionomycin for activation. Apoptosis in peripheral T-cells and Jurkat cells was induced by irradiation with UVB (120 mJ/cm2). In addition, T-cells or Jurkat cells were cultured for the indicated time with anti-Fas antibody CH11. The CH11-induced apoptosis was inhibited by the pan-caspase inhibitor zVAD-fmk. For detection of apoptosis, cells were analysed by cytofluorometry for morphological changes typical for apoptosis. The reliability of the apoptotic cell gate was confirmed by staining with FITC-labelled annexin-V in the presence ofpropidium iodide (PI). For FACS analysis of CD62L expression on the cell-surface immunofluorescence was performed using FITC-conjugated anti-CD62L and PE-conjugated anti-CD3 antibodies. Soluble CD62L (sCD62L) in the cell supernatants was measured by standard ELISA technique. Assays were performed in the presence and absence of metalloprotease inhibitor KB8301. RESULTS: PBMC from healthy volunteers undergoing apoptosis following UVB irradiation selectively shed CD62L, whereas the expression of the lineage-specific marker CD3 showed only minor changes. Shedding was blocked by the hydroxamic acid-based metalloprotease inhibitor KB8301. When Jurkat cells were treated with the caspase inhibitor zVAD-fmk, anti-CD95 antibodies did not induce apoptosis, and the expression of CD62L remained unaltered. CONCLUSION: UVB or ionizing radiation induce apoptosis in lymphocytes. The loss of CD62L is associated with apoptosis and will influence lymphocyte trafficking and, by excluding them from CD62L-mediated adhesion and tissue invasion, might contribute to the regulation of inflammation.     

新型四物胶囊对辐射损伤小鼠造血功能的影响

目的评价新型四物胶囊对60Coγ射线所致小鼠造血功能损伤的影响,为该药的临床研究提供参考依据。方法采用2.5 Gy60Coγ射线全身照射,照后连续给药7 d。正常组和模型组给予等体积的蒸馏水,新型四物胶囊高、中、低剂量（20.0、10.0、5.0 g.kg-1）组分别在照前、照后第1、4、7、11、14、17、23天检测外周血象,同时在照后第7天进行CD34＋细胞检测、骨髓造血祖细胞集落培养。结果新型四物胶囊各剂量在造模后7 d提高CD34＋细胞数,促进CFU-GM增殖,同时高剂量还促进CFU-E、BFU-E及CFU-Mix增殖;第7～14天显著升高白细胞与血小板数。结论新型四物胶囊可有效改善60Coγ射线对小鼠所致的造血损伤,提高骨髓造血功能,进而促进外周血各组分恢复正常。     

低剂量辐射对脐血的免疫刺激作用

目的：探讨低剂量辐射对脐血T淋巴细胞膜分子表达，IL－2分泌及LAK细胞体外抗肿瘤活性的影响。方法：新鲜分离的脐血淋巴细胞及LAK前体细胞接受低剂量γ射线照射，分别用直接免疫荧光标记流式细胞术，MTT法及3H-TdR释放实验检测T淋巴细胞膜分子的表达，IL－2分泌的LAK体外杀伤肿瘤靶细胞（K562，HL－60）活性。结果：（1）62mGyγ射线照射后，脐血淋巴细胞CD3，TCR／CD3复合物，CD4，CD8分子表达显著上调，且均在4－24h，人随时间推移而逐步增强，CD4／CD8比值无显著性变化；（2）62mGy γ射线照射后，脐血单个核细胞上清IL－2活性随培养时间推多逐渐增强，不同时间点比较差异均有显著性（P＜0．05）；（3）脐血LAK细胞对K562和HL－60的杀伤活性与成人外周血相比差异无显著性（P＞0．05），接受低剂量辐射的脐血LAK细胞对K562和HL－60的细胞毒性显著高于非照射组（P＜0．01），结论：低剂量辐射可促进脐血T淋巴细胞的成熟，活化和信号的转导及IL－2的分泌，增强脐血LAK杀伤肿瘤靶细胞的细胞毒活性，从而可能在脐血移植中加速免疫功能重建，增强移植物抗白血病效应。     

粒细胞集落刺激因子对急性辐射损伤小鼠中枢及外周血淋巴细胞亚群重建的影响

目的 观察粒细胞集落刺激因子(G-CSF)对急性辐射损伤小鼠中枢及外周血淋巴细胞亚群重建的影响.方法 雌性BALB/c小鼠60只经6 Gy照射后随机分为照射组、G-CSF+照射组.G-CSF+照射组小鼠给与重组人G-CSF 100μg·kg-1·d-1皮下注射,连续14 d,照射组小鼠给与等体积磷酸盐缓冲液(PBS)皮下注射,连续14 d,另设空白对照组小鼠20只.照后7、14、21和28d颈部脱臼处死小鼠,取出胸腺制成单个核细胞悬液,使用流式细胞仪检测胸腺CD4+CD8+、CD4+CD8-、CD4-CD8+、CD4-CD8-细胞亚群的比例.使用全血细胞计数仪进行外周血白细胞计数及淋巴细胞绝对值测定,流式细胞仪检测照后14、28、60 d外周血淋巴细胞亚群比例,CCK-8法检测脂多糖(LPS)、刀豆蛋白A(ConA)刺激后脾脏淋巴细胞增殖指数.结果 照后7 d胸腺CD4+CD8+细胞比例降至最低,14 d出现反弹,21 d再次下降,以后逐渐恢复.照后28 d G-CSF+照射组CD4+CD8+细胞比例恢复正常并高于照射组(t=12.22,P＜0.05).照后21 d G-CSF+照射组CD4-CD8+细胞比例亦明显高于照射组(t=3.77,P＜0.05).照后7 d外周血白细胞及淋巴细胞绝对值降至最低,照后14和60 d,G-CSF+照射组CD3+CD8+T细胞比例明显高于照射组(t=4.31,5.78,P＜0.05),但两组间CD3+CD4+T细胞比例在各时间点无明显差异.G-CSF+照射组B淋巴细胞比例在照后14 d明显低于照射组(t=7.3,P＜0.05),但很快恢复,照后28和60 d两组B淋巴细胞比例差异无统计学意义.照后14 d,G-CSF+照射组脾脏淋巴细胞对LPS、ConA刺激的增殖指数分别为照射组的4.37和2.98倍.结论 G-CSF可促进照后胸腺细胞亚群的恢复,提高外周血淋巴细胞数量,调节外周血淋巴细胞亚群比例,提高淋巴细胞增殖功能,促进急性辐射损伤后中枢及外周免疫重建.

Abstract：

Objective To investigate the effects of recombinant human granulocyte colonystimulating factor(G-CSF) on central and peripheral lymphocyte subset reconstitution after a sublethal dose of irradiation. Methods Sixty female BALB/c mice were given a 6.0 Gy γ-ray total body irradiation (TBI) and randomly divided into 2 equal groups. The mice in G-CSF + TBI group were injected subcutaneously with recombinant human G-CSF 100 μg·kg-1·d-1 for 14 d and the mice in TBI group were injected subcutaneously with the same volume of phosphate buffered solution (PBS) once daily for 14 d. 7,14,21, and 28 d later the mice were killed and their thymus were taken out to prepare of the mononuclear cell suspension to analysis the percentage of thymic CD4 + CD8 + double positive, CD4 +CD8 - single positive, CD4 - CD8 + single positive and CD4 - CD8 - double negtive cells by flow cytometry. Peripheral blood samples were collected from the caudal vein twice a week, and the white blood cell(WBC) counts and absolute number of lymphocytes were assessed by automatic hemocyte analyzer. 14,28, and 60 d later blood samples were collected from angular vein to examine the peripheral lymphocyte subsets by flow cytometry. Cell counting kit-8 was used to detect lipopolysaccharide (LPS) or concanavalin A (ConA) stimulated splenic lymphocyte proliferation. Results The percentage of thymic CD4 + CD8 +double positive cells decreased 7 d after irradiation, rebounded at 14 d, decreased again at 21 d, and then got a permanent recovery. 28 d after irradiation the percentage of thymic CD4 + CD8 + double positive cells in the G-CSF + TBI group recovered to normal and was significantly higher than that of the TBI group (t =12. 22, P < 0. 05). 21d after irradiation the percentage of thymic CD4-CD8 + single positive cells of the G-CSF + TBI group was significantly higher than that of the TBI group (t = 3.77, P < 0. 05). The peripheral WBCs and lymphocytes decreased to the lowest levels 7 d after irradiation and then gradually increased, however, WBCs and lymphoeytes of the G-CSF + TBI group began to recover earlier and faster than the TBI group. The proportion of CD3 + CD8 + T cells of the G-CSF + TBI group was significantly higher than that of the TBI group 14 and 60 d after irradiation (t =4. 31,5.78, P <0.05). But there was no significant difference in the proportion of CD3 + CD4 + T cells between the two groups. The proportion of B lymphoeytes of the G-CSF + TBI group was significantly lower than that of the TBI group 14 d after irradiation(t =7.30, P <0.05), but it recovered quickly, and there were no significant differences in the proportion of B lymphoeytes between the two groups 28 and 60 d after irradiation. The proliferation indexes of splenic lymphocytes in response to LPS and ConA in the G-CSF + TBI group were 4. 37 and 2.98 times higher than those in the TBI group 14 d after irradiation. Conclusions G-CSF could accelerate the recovery of central and peripheral lymphocyte subsets, raise the absolute number of lymphocytes, and enhance their proliferative function, which contributes to the central and peripheral immune reconstitution after acute irradiation.     

低剂量率裂变中子照射对大鼠外周血淋巴细胞亚群的影响

目的 探讨低剂量率中子长期照射对大鼠外周血细胞亚群的影响。方法 96只雄性大鼠分为对照组和照射组,照射组每天用低剂量率中子²⁵²Cf(吸收剂量率为0.35 mGy/h)照射20.5h,在照射的第14、28、42、56和70天(累积剂量分别为0.1、0.2、0.3、0.4和0.5 Gy)及停止照射后第35天各取8只大鼠,用血细胞计数仪检测大鼠外周血WBC、用流式细胞仪检测外周血CD4⁺CD3⁺、 CD8⁺CD3⁺、CD45RA⁺/CD161α⁺亚群的变化。结果 累积剂量为0.3、0.4及0.5 Gy时WBC明显低于对照组(P<0.05),停止照射后35 d,WBC显著低于对照组(P<0.01);累积剂量为0.1、0.3、0.4、0.5 Gy及停止照射后35 d,外周血CD4⁺CD3^-细胞比例显著高于对照组(P<0.01或<0.05);累积剂量为0.2和0.3 Gy时CD8⁺CD3^-细胞比例显著高于对照组(P<0.05或P<0.01)。而累积剂量为0.1 Gy时的CD4⁺CD3⁺细胞比例及0.1和0.2 Gy时的CD8⁺CD3⁺细胞比例明显高于同一天对照组(P<0.01或<0.05)。另外,低剂量率中子长期照射可使累积剂量为0.2~0.3 Gy的外周血NK细胞(CD161α⁺ CD45RA^-)显著升高,累积剂量为0.1~0.5 Gy及停止照射后35 d照射组的外周血B细胞(CD161α^- CD45RA⁺)比例明显下降。结论 低剂量率裂变中子长期照射可使外周血淋巴细胞TCR基因突变,使大鼠外周血WBC减少,淋巴细胞中B细胞减少,NK细胞细胞比例升高,这种变化在停止照射后一段时间仍可能难以恢复。     

HLA-DR/CD14在外周血单核细胞中的表达及其临床意义

目的 探讨外周血单核细胞表面HLA-DR/CD14的表达率及其临床意义.方法 收集2008年4月-2009年4月的住院患者140例,其中ICU急重症疾病组101例,其他疾病组39例,以同期20名健康体检者为正常对照组,应用流式细胞术检测各组外周血单核细胞表面HLA-DR/CD14表达率,并测定急重症疾病组C反应蛋白(C...     

Lymphocyte subsets and their H2AX phosphorylation in response to in vivo irradiation in rats

Abstract

Purpose: The objective of the study was to investigate differences in the radiosensitivity of rat peripheral blood lymphocyte subsets identified by expression of surface clusters of differentiation markers (CD3, CD4, CD8, CD45RA, CD161) after whole-body in vivo gamma-ray irradiation and to assess their individual histone H2AX phosphorylation as an early cell response to irradiation.

Materials and methods: The relative representations of CD45RA B-lymphocytes, CD161 natural killer cells (NK cells), CD3CD4 T-lymphocyte subset and CD3CD8 T-lymphocyte subset in the rat peripheral blood were studied 24–72 hours after irradiation in a dose range of 0–5 Gy. Their intracellular H2AX phosphorylation (γ-H2AX) after 4 Gy and 9 Gy whole-body in vivo irradiation was assessed by multicolour flow cytometry.

Results: We determined the linear dose response of radioresistant CD161 NK cells (24 h), both radiosensitive T-lymphocyte subsets (24 h) and CD45RA B-lymphocytes (72 h) after in vivo irradiation. CD45RA B-lymphocytes showed the highest radiosensitivity and we observed pronounced H2AX phosphorylation which remained expressed in these cells for over 4 h after irradiation.

Conclusion: The combination of the surface immunophenotyping together with intracellular detection of γ-H2AX offers the possibility to assess the absorbed dose of ionizing irradiation with high sensitivity post irradiation and could be successfully applied to biodosimetry.     

细胞因子治疗4.5Gyγ射线照射比格犬造血损伤的机制初探

目的 探讨多种细胞因子配伍应用治疗4.5 Gy γ射线照射比格犬造血系统损伤的作用及可能机制。方法 16只比格犬均给予4.5 Gy ⁶⁰Co γ射线全身照射,随机分为照射对照、综合对症和细胞因子3组。细胞因子组在综合对症支持治疗的基础上应用rhG-CSF、rhIL-11和rhIL-2联合治疗,采用流式细胞术检测外周血中CD34+细胞含量、有核细胞周期及凋亡比例。结果 4.5 Gy γ射线照射犬外周血中CD34+细胞含量在照射后1 d明显下降(照射对照组和综合对症组分别为照前值的61.3%和52.1%),G₀/G₁期有核细胞比例增加(分别为99.27%和99.49%),且凋亡率(分别为26.93%和21.29%)和坏死率(分别为3.27%和4.14%)明显升高(与照前值比较, P<0.05);而经过细胞因子治疗后,外周血中CD34+细胞含量在照射后1 d即明显升高(为照前值的135.6%),G₀/G₁期有核细胞比例(99.71%)进一步增加,其凋亡率(5.66%)和坏死率(1.60%)明显低于照射对照和综合对症组。结论 本研究的细胞因子组合可能通过动员骨髓中CD34+细胞到外周血,使细胞周期阻滞在G₀/G₁期,减少细胞凋亡,从而促进极重度骨髓型急性放射病犬造血功能的恢复。     

Activation of immunological network by chronic low-dose-rate irradiation in wild-type mouse strains: analysis of immune cell populations and surface molecules

PURPOSE: To analyse the effects of chronic whole body low-dose-rate irradiation on the immune system in various wild-type mouse strains in comparison with the effects from acute high-dose-rate irradiation. MATERIALS AND METHODS: Wild-type mouse strains (C57BL/6, BALB/c, C3H/He, DBA/1, DBA/2 and CBA) were observed after chronic low-dose-rate gamma irradiation at 1.2 mGy hour(-1) by intensive analysis of immune cell populations and their various surface molecules, together with antibody-producing activity both with and without immunization by sheep red blood cells (SRBC). The cell surface functional molecules [cluster of differentiation (CD) 3, CD4, CD8, CD19, CD45R/B220, intercellular adhesion molecule (ICAM)-1, Fas, natural killer (NK)-1.1, chemokine [C-X-C motif] receptor 4 (CXCR4) and chemokine [C-C motif] receptor 5 (CCR5)] and activation molecules [thymocyte-activating molecule (THAM), CD28, CD40, CD44H, CD70, B7-1, B7-2, OX-40 antigen, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), CD30 ligand and CD40 ligand] were studied in the bone marrow, thymus, spleen, lymph nodes and peripheral blood by flow cytometry. RESULTS: By chronic low-dose-rate irradiation alone, CD4+ T cells and CD8 molecule expression increased significantly by a maximum of 30%, while CD40+ B cells decreased significantly. Increases of CD4+ T cells, CD40+ B cells and anti-SRBC antibody-producing cells by immunization were significantly enhanced by continuous low-dose-rate irradiation at 1.2 mGy hour(-1). CD3- CD4+ T cells, representative of abnormal immune cells, were absent in the chronically low-dose-rate-irradiated mice, while a dose-dependent increase of these cells was found in acutely high-dose-rate-irradiated mice given the same total doses. CONCLUSION: Chronic low-dose-rate radiation activated the immune system of the whole body.