低剂量全身照射抑制小鼠癌细胞播散

小鼠受５０，７５，１００和１５０ｍＧｙＸ射线全身照射后２４小时经球后静脉注入Ｌｅｗｉｓ肺癌或Ｂ１６黑色素瘤细胞。注后１４天以计数肺肿瘤结节数为指标，发现受照小鼠癌细胞播散明显低于假照射对照小鼠。Ｌｅｗｉｓ肺癌细胞注入前２４小时接受７５ｍＧｙ全身照射小鼠与注入相同癌细胞数的假照射小鼠比较，发现照后２～６天脾脏ＮＫ细胞活性和ＩＬ－２分泌均增高。提示低剂量辐射可能通过增强免疫反应抑制癌细胞播散。     

Th2 cells as effectors in postirradiation pulmonary damage preceding fibrosis in the rat.

PURPOSE: Radiation-induced pneumonitis and subsequent pulmonary fibrosis are important dose-limiting complications of radiotherapy. Their pathogenesis is known only in part. T-lymphocytes comprise a significant part of the infiltrating cells but little is known about their role. The aim of this study was to define the function of T-lymphocytes during development of postirradiation pneumonitis and pulmonary fibrosis. MATERIALS AND METHODS: Rats received a unilateral lung irradiation of 20 Gy. Kinetics of T-lymphocytes isolated from irradiated and non-irradiated lungs were analysed. Subsequent CD4 depletion experiments were performed to affirm the importance of CD4+ T-cells in the development of lung fibrosis. Finally, the T helper-cell subtype of the T-lymphocytes was analysed by determining the cytokine mRNA by RT-PCR. RESULTS: A selective increase of CD4+ T-cells was observed peaking 4 weeks after irradiation in the irradiated lungs. When rats were depleted of these cells, the postirradiation thickening of parenchyma was significantly reduced as determined by morphometric analysis of lung tissue sections. In addition, it was found that IL-4 mRNA was selectively increased in the CD4+ T-cells isolated from irradiated lungs, which indicates a lymphocyte reactivity dominated by Th2 cells. CONCLUSION: The results suggest a critical role for Th2 CD4+ T-lymphocytes in the pathogenesis of radiation-induced pneumonitis preceding lung fibrosis.     

放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及对Th1/Th2免疫细胞比例的影响

目的 探讨放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及其对辅助性T细胞1(Th1)/Th2细胞比例的影响.方法 建立宫颈癌荷瘤小鼠模型,随机分为荷瘤组和放疗组,每组各10只,另设对照组10只.放疗组进行放疗干预14天,荷瘤组和对照组不治疗.放疗后4、6、8、10、12、14天测量肿瘤体积;末次治疗后,ELISA法测定血清干扰素...     

12周游泳运动对老龄小鼠免疫细胞功能的影响

对游泳１２周后的老龄Ｃ５７ＢＬ／６小鼠脾脏Ｔ细胞对ＣｏｎＡ的增殖反应能力、ＮＫ细胞活性及ＩＬ－１活性进行了研究。结果：（１）与年轻小鼠相比,老龄小鼠Ｔ淋巴细胞对ＣｏｎＡ的增殖能力、ＮＫ细胞活性、ＩＬ－１活性略有下降,但无显著差异（Ｐ＜０．０５）。（２）１２周训练后,隔天训练的老龄鼠Ｔ淋巴细胞对ＣｏｎＡ的增殖反应能力显著升高。（３）每天训练的老龄小鼠Ｔ淋巴细胞的增殖反应能力下降（Ｐ＜０．０５）。（４）１２周的训练没有使ＮＫ亚细胞和ＩＬ－１的活性发生显著性变化。     

不同剂量辐射诱导小鼠胸腺Th1-Th2-Th3型细胞相关基因的功能分析

目的 应用功能分类基因芯片技术,分析高、低剂量全身照射对小鼠胸腺细胞中Th1、Th2及Th3/Tr1各亚型功能相关基因的差异表达,探讨辐射免疫效应的分子机制.方法 健康ICR小鼠按随机数字表法分为低剂量组(0.075 Gy)、高剂量组(2.0 Gy)和假照组,于照射后16 h处死小鼠取胸腺组织,应用细胞因子与炎症反应PCR芯片技术进行Th1-Th2-Th3功能分类芯片分析.结果 低剂量(0.075 Gy)X射线全身照射后小鼠胸腺细胞中有8个基因表达上调,5个基因表达下调;高剂量(2.0 Gy)X射线全身照射后小鼠胸腺细胞中有54个基因表达上调,3个基因表达下调.具体有Th型细胞相关基因、Th2型细胞相关基因、Th3/Tr1型细胞相关基因、Th1/Th2型免疫应答基因以及转录因子相关基因.其中,低剂量辐射诱导胸腺中的Th1型细胞相关基因Stat4和Socs1的表达上调,而对Th2型和Th3/Tr型细胞相关基因IL-4ra、Cebpb、Gata3及Tgfb3下调,最终导致Th1型免疫应答基因Sftpd上调.高剂量辐射均可诱导Th1、Th2和Th3/Tr型细胞相关基因的上调,但Th1型免疫应答基因表达无变化,而Th2型免疫应答相关基因Cd86、IL-18、IL-10以及Irf4上调.结论 低剂量辐射诱导Th1型免疫应答,而高剂量辐射诱导Th2型免疫应答.     

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.     

太极拳运动对中老年女性Th1/Th2平衡影响的机制研究

目的:从细胞因子角度在基因表达水平上探讨太极拳运动前后调节性T细胞(regulatoryT cells,Treg)对辅助性T细胞(helper T cell,Th)亚群Th1/Th2平衡的影响。方法:将自愿参加本实验的34名中老年女性随机分为太极拳组和对照组。太极拳组参加为期32周、每周3次、每次1小时的24式和42式太极拳锻炼;对照组不锻炼,保持原有生活状态。实验前后采集受试者外周血,使用流式细胞术检测Treg细胞数量;使用Real-time PCR定量分析Th1型淋巴细胞相关细胞因子干扰素-γ(Interferon-gamma,IFN-γ)和Th2型淋巴细胞相关细胞因子白介素-4(Interleukin-4,IL-4)、Treg相关细胞因子白介素-10(Interleukin-10,IL-10)和转化生长因子-β(transforming growth factor,TGF-β)以及细胞毒T淋巴细胞相关抗原-4(cytotoxic T lymphocyte-associated antigen-4,CTLA-4)mRNA表达。结果:实验后,太极拳组IFN-γ、TGF-β、CTLA-4和IL-10 mRNA表达量较实验前显著上升(P<0.01),IFN-γ与IL-4 mRNA表达量比值显著上升(P<0.05),Treg细胞占CD4+T细胞比例显著上升(P<0.01)。实验后,对照组除TGF-βmRNA表达下降(P<0.05)外,其他指标变化均无统计学意义。结论:太极拳运动影响外周血Treg细胞数量及相关细胞因子mRNA表达,提高中老年女性Th1/Th2型细胞因子mRNA表达量比值,在基因表达水平上改善老年女性Th1/Th2失衡。     

Irradiated KHYG-1 retains cytotoxicity: potential for adoptive immunotherapy with a natural killer cell line

PURPOSE: To evaluate gamma-irradiation on KHYG-1, a highly cytotoxic natural killer (NK) cell line and potential candidate for cancer immunotherapy. METHODS AND MATERIALS: The NK cell line KHYG-1 was irradiated at 1 gray (Gy) to 50 Gy with gamma-irradiation, and evaluated for cell proliferation, cell survival, and cytotoxicity against tumor targets. RESULTS: We showed that a dose of at least 10 Gy was sufficient to inhibit proliferation of KHYG-1 within the first day but not its cytolytic activity. While 50 Gy had an apoptotic effect in the first hours after irradiation, the killing of K562 and HL60 targets was not different from non-irradiated cells but was reduced for the Ph + myeloid leukemia lines, EM-2 and EM-3. CONCLUSIONS: gamma-irradiation (at least 10 Gy) of KHYG-1 inhibits cell proliferation but does not diminish its enhanced cytolytic activity against several tumor targets. This study suggests that KHYG-1 may be a feasible immunotherapeutic agent in the treatment of cancers.     

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 γ 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.     

Modulation of immune response by the acute and chronic exposure to high altitude

PURPOSE: The chronic exposure at high altitude (HA) represents an ideal model for evaluating the in vivo effects of hypobaric hypoxia. Taking advantage of the EV-K2-CNR Pyramid, this study was designed to evaluate whether acute and chronic hypoxia differently modulates the in vivo immune responses. METHODS: The study includes 13 healthy female moderately active volunteers participating to the Italian HA project EV-K2-CNR. Peripheral blood lymphocytes, collected at sea level and at HA in the Pyramid Laboratory of CNR, Nepal (5050 m), were immunologically characterized by flow cytometry and a series of molecular and functional analyses. RESULTS: Flow cytometric analyses showed that: a) CD3+ T lymphocytes significantly decreased during both acute and chronic exposure to HA, b) T-cell fall was totally due to CD4+ T-cell reduction, c) B lymphocytes were not influenced by the exposure to HA, and d) natural killer (NK) cells significantly increased during acute and chronic exposure. The evaluation of the Th1/Th2 pattern demonstrated a significant decrease of the expression of the Th1 cytokine interferon-gamma (IFN-gamma) by circulating T cells during acute and chronic exposure to HA. The expression by T cells of CXCR3, a chemokine receptor typically expressed by Th1/Tc1 cells, paralleled the decrease of IFN-gamma. On the contrary, the expression of IL-4 was not conditioned by the exposure to HA. Finally, functional studies showed a significant reduction of the proliferative activity in response to mitogen (PHA) both in acute and chronic HA exposure. Despite the increased number of NK cells, NK cytotoxic activity was not influenced by the HA exposure. CONCLUSIONS: Our results indicate that the in vivo exposure to HA leads to an impairment of the homeostatic regulation of Th1/Th2 immune balance that potentially could favor long-term immunological alterations and increase the risk of infections.     

Treg分化对放射性肺损伤的影响

目的 探讨调节性T细胞（Treg）的分化对放射性肺损伤的影响及其作用机制。 方法 建立Treg抑制小鼠模型,按随机数字表法将C57BL/6小鼠分成4组:空白对照组、单纯照射组、照射+免疫球蛋白G（IgG）组和照射+CD25组,每组12只,除空白对照组外其余3组小鼠给予单次20 Gy X射线全胸照射,照射+IgG组和照射+CD25组小鼠每周腹腔注射IgG抗体和CD25抗体。分别于照射后第4周和第8周各处死小鼠6只,采用流式细胞术检测小鼠肺组织内CD25+Foxp3+Treg（Foxp3:叉头样转录因子3）的百分比以鉴定模型是否建立成功;采用Western blot法检测单纯照射组小鼠肺组织内神经纤毛蛋白1（NRP1）的表达;采用免疫荧光法检测每组小鼠肺组织内CD25+NRP1+Treg的百分比;拍照并观察每组小鼠皮肤的损伤情况,采用苏木精-伊红染色法检测小鼠肺组织的病理学改变;采用酶联免疫吸附测定法检测每组小鼠肺组织内转化生长因子β1（TGF-β1）、白细胞介素（IL）-17A、干扰素γ（IFN-γ）、IL-2和IL-4的水平变化。两组间比较采用独立样本t检验。 结果 流式细胞术检测结果显示,照射后第4周和第8周,单纯照射组小鼠肺组织内CD25+Foxp3+Treg百分比[（1.73±0.04）%、（2.13±0.15）%]均较空白对照组[（1.14±0.02）%、（1.70±0.06）%] 明显升高,差异均有统计学意义（t=?26.680、?4.545,P=0.000、0.010）,抑制Treg后,第4周和第8周时照射+CD25组小鼠肺组织内CD25+Foxp3+Treg百分比[（0.72±0.14）%、（0.27±0.02）%]均较单纯照射组明显降低,差异均有统计学意义（t=5.296、37.538,均P=0.000）。Western blot结果显示,照射后第4周和第8周,单纯照射组小鼠肺组织内NRP1蛋白表达水平均较空白对照组升高,差异均有统计学意义（t=?7.341、?9.127,均P=0.000）。免疫荧光法检测结果显示,照射后第4周和第8周,单纯照射组小鼠肺组织内CD25+NRP1+Treg的百分比均较空白对照组升高,而照射+CD25组CD25+NRP1+Treg百分比均较单纯照射组降低,且差异均有统计学意义（t=8.926、14.457,P=0.001、0.000）。观察小鼠皮肤损伤程度后发现,照射后第4周和第8周,单纯照射组小鼠皮肤损伤严重,而照射+CD25组小鼠照射后第4周时皮肤基本完好,第8周时出现脱毛脱皮。病理学结果显示,照射后第4周和第8周,与空白对照组相比,单纯照射组小鼠的肺组织结构破坏,肺泡壁增厚,细胞外基质增多,而照射+CD25组小鼠的肺组织结构完整,肺泡壁纤细。酶联免疫吸附测定结果显示,与空白对照组相比,照射后第4周,单纯照射组小鼠肺组织内IL-17A和IL-4的水平均升高,差异均有统计学意义（t=?8.492、?15.796,P=0.001、0.000）,照射后第8周,TGF-β1和IL-17A水平升高,差异均有统计学意义（t=?11.072、?7.167,P=0.000、0.002）,IL-2水平在第4周和第8周时均降低,IFN-γ水平在第4周时升高,差异有统计学意义（t=?27.393,P=0.000）,第8周时下降;与单纯照射组相比,照射+CD25组小鼠TGF-β1和IL-17A水平在第4周和第8周时均降低（t=6.037、4.524、5.496、4.772,均P=0.000）,IFN-γ水平升高（t=?7.006、?12.565,P=0.002、0.000）,差异均有统计学意义,而IL-2和IL-4水平在第4周时均降低,第8周时均明显升高,差异均有统计学意义（t=2.866、?9.090、8.833、?7.191,均P=0.000）。 结论 放射性肺损伤小鼠的肺组织中出现Treg分化,并增强分泌TGF-β1促炎因子,同时干扰辅助T细胞（Th1、Th2型）细胞因子的平衡来促进放射性肺损伤的发生。     

X射线全身照射后脾细胞内[Ca2+)]i对Con A反应性的变化

目的 研究电离辐射对ConA激活的脾细胞内游离钙离子[Ca²⁺]i)动员的影响, 以探讨电离辐射免疫抑制作用的发生机理。方法 采用Fura2/AM双波长荧光测定法检测了X射线全身照射后的小鼠脾细胞内[Ca²⁺]i对ConA反应性的变化。结果 小鼠接受0、0.5、1、2、4和6Gy吸收剂量的X射线全身照射后24小时, 脾细胞内[Ca²⁺]i对ConA反应性呈剂量依赖性下降, 表现为[Ca²⁺]i上升幅度减小、上升至峰值时间延长。2GyX射线全身照射后的时程观察表明, 照后2小时细胞内[Ca²⁺]i对ConA反应性开始下降, 24小时达最低点, 照后5天才略有回升。结论 电离辐射所致免疫功能抑制与其抑制淋巴细胞内[Ca²⁺]i动员等信息传递过程有关。     

电离辐射对小鼠胸腺Th17细胞相关细胞因子的影响

目的 通过研究电离辐射对小鼠胸腺Th17细胞相关细胞因子的影响,探讨高、低剂量辐射诱导不同的免疫效应中Th17细胞功能。方法 将健康ICR小鼠按随机数字表法分为健康对照组、低剂量照射组(0.05、0.075 Gy)和高剂量照射组(0.5、1.0、2.0、4.0 Gy)探讨剂量-效应关系,用X射线深部治疗机进行不同剂量的全身照射,于照射后24 h处死。同时,探讨时间-效应关系,即分为健康对照组、低剂量照射组(0.075 Gy)和高剂量照射组(2.0 Gy),于照射后12、24、48 h处死,取胸腺组织制备成组织匀浆,ELISA法检测小鼠胸腺细胞中白介素-17a(IL-17a)与白介素-21(IL-21)的浓度。结果 在时间-效应结果中,与健康对照组相比,0.075 Gy照射组胸腺细胞IL-17a和IL-21分泌量呈下降趋势,其分泌量于48 h降到最低(t=3.85、4.73,P<0.05);而2.0 Gy照射组均呈大幅度上升趋势,其分泌量在48 h达到最高(t=-6.74、-6.19,P<0.05);在剂量-效应结果中,与健康对照组相比,较低剂量照射组胸腺细胞IL-17a与IL-21分泌量下降,在0.05 Gy最低(t=8.39、16.45,P<0.05);较高剂量照射组胸腺细胞的分泌量上升,在4.0 Gy时升至最高(t=-15.60、-18.62,P<0.05)。结论 高剂量辐射可以诱导小鼠胸腺细胞IL-17a与IL-21分泌量的增加,而低剂量辐射使其下降,表明Th17细胞相关的细胞因子在低剂量辐射诱导的免疫功能增强效应和高剂量辐射诱导免疫抑制效应中起着重要的作用。     

小鼠胸腺和牌细胞对淋巴因子反应的辐射剂量效应关系

作者研究了Ｃ５７ＢＬ／６小鼠经０．１～８．０ＧｙＸ射线全身照射后淋巴因子效应细胞反应性的变化．结果发现，照后２４小时胸腺细胞对ＩＬ－１反应的剂量效应曲线由两个斜率不同的成分组成，其Ｄ３７，分别为１．６５和４．０９Ｇｙ；照后１２和２４小时脾细胞对ＩＬ－２反应的Ｄ３７分别为５．５８和３．４６Ｇｙ；ＣＴＬＬ－２细胞在为０．５～１０Ｇｙ剂量范围内，对ＩＬ－２反应性呈剂量依赖性降低，Ｄ３７为８．７７Ｇｙ。提示ＩＬ－２效应细胞的辐射抗性高于ＩＬ－１效应细胞．     

X射线全身照射对小鼠脾细胞转铁蛋白受体表达的影响

目的转铁蛋白受体（ＴｆＲ）是Ｔ淋巴细胞受抗原或丝裂原刺激后表达在细胞表面的重要受体之一,与Ｔ细胞的活化和增殖有着密切关系。目前尚未见国内外有关ＴｆＲ辐射效应研究的报道。研究大剂量电离辐射后ＴｆＲ表达的变化及作用,对阐明辐射抑制机体免疫功能的机制有着重要意义。方法本文采用流式细胞术的方法观察了不同剂量Ｘ射线全身照射对小鼠脾细胞ＴｆＲ表达的影响以及４ＧｙＸ射线全身照射后不同时间ＴｆＲ表达的变化。结果０５～６ＧｙＸ射线全身照射后２４小时,脾脏ＴｆＲ阳性细胞数从１Ｇｙ开始随照射剂量的增加而下降,且呈明显的剂量依赖性。４ＧｙＸ射线全身照射后１２～７２小时,脾脏ＴｆＲ阳性细胞数于照后１２小时开始下降,２４、４８小时降至最低值（Ｐ＜０．０５,Ｐ＜０．０１）,７２小时开始回升。结论大剂量电离辐射抑制小鼠脾细胞ＴｆＲ的表达,并有明显剂量依赖性;ＴｆＲ表达的下降可能与辐射抑制ＩＬ２的分泌和ＩＬ２受体的表达有关。     

用^3H—TdR释放法测定小鼠NK细胞的辐射敏感性

用~3H—TdR释放法测定C_(57)BL/6小鼠脾细胞对YAC-1细胞林的NK活性,首次将该法应用于研究NK细胞对γ线的辐射敏感性,得出如下结论:(1)小鼠整体照射后24h脾脏NK活性的D_(37)约为17Gy,D_0约为11Gy;在24～32Gy范围内仍保留着30%的NK活性,存活曲线为反“S”形,验证了NK细胞总体对辐射的相对耐受性。(2)脾细胞离体或整体照射1～2Gy后即刻NK活性均迅速下降,在2～24Gy内,离体和整体照射组的NK活性分别维持在40%～80%和50%,前者高于后者,说明NK细胞对离体照射比对整体照射更不敏感。(3)小鼠整体照射后24h,全脾细胞数在较小剂量(<4Gy)内急剧下降,然后随剂量增大变化平缓。可以推测NK活性的变化与脾细胞总数的改变有一定关系。(4)综合分析本实验结果,可以设想NK细胞本身可能存在着辐射敏感性不同的亚群。(5)用~3H—TdR释放法测定NK细胞的辐射敏感性,自然释放率低,重复性好,可靠易行。