肿瘤坏死因子对正常和甲亢甲状腺细胞功能调控的对比观察

采用细胞单层培养方法，以ｃＡＭＰ为观察指标，研究肿瘤坏死因子对正常和甲亢甲状腺细胞功能调控的特征。结果显示：（１）１０＾－３和１０＾－１Ｕ／ｍｌ的ＴＮＦ－α对其状态下正常甲状腺细胞生成ｃＡＭＰ的值无显著影响，当其浓度为１０和１０＾３Ｕ／ｍｌ时，ｃＡＭＰ释放明显增加。ＴＮＦ－α在１０＾－３－１０Ｕ／ｍｌ的剂量范围内，对甲亢甲状腺细胞基础ｃＡＭＰ的生成无明显影响，但１０＾３Ｕ／ｍｌ的ＴＮＦ－α则显著促     

α—干扰素对正常与甲亢甲状腺细胞生成c—AMP的调节作用

采用甲状腺细胞单层培养及标记免疫分析法，对比研究α－干扰素（ＩＦＮ－α）对正常与Ｇｒａｖｅｓ病（ＧＤ）甲状腺细胞生成ｃＡＭＰ的影响，结果显示：（１）基础状态下，１０＾－３、１０＾－１和１０ｕ／ｍｌ的ＩＦＮ－α可刺激正常甲状腺细胞产生ＣＡＭＰ，刺激强度随ＩＦＮ－α浓度的增大而减弱，当试验剂量达１０＾３ｕ／ｍｌ时，ＣＡＭＰ的生成量与无刺激的对照组比较无统计学差异，此浓度区间的ＩＦＮ－α对ＧＤ甲状腺细胞     

人绒毛膜促性腺激素对甲状腺细胞cAMP生成的影响

采用细胞培养方法，研究人绒毛膜促性腺激素（ｈＣＧ）对甲状腺细胞ｃＡＭＰ生成的调节作用。结果显示：在１０￣１０＾４Ｕ／Ｌ的剂量区间，ｈＣＧ可明显刺激甲状腺细胞释放ｃＡＭＰ，ｈＣＧ浓度与ｃＡＭＰ产值之间存在明显的量效依赖关系。１０＾５Ｕ／Ｌ的ｈＣＧ亦显著促进ｃＡＭＰ的分泌，但其刺激强度低于１０＾４Ｕ／Ｌ的ｈＣＧ。提示ｈＣＧ具有类似ＴＳＨ的作用，是孕期母体甲状腺功能的重要调节因子。     

白细胞介素6在Graves病的发病及骨代谢中的作用

采用白细胞介素 ６依赖性细胞株ＭＨ６０· ＢＳＦ增殖反应ＭＴＴ法，测定了 ５３例 Ｇｒａｖｅｓ病（ＧＤ）患者外周血单个核细胞（ＰＢＭＣ）培养上清中ＩＬ－６水平。结果未治疗组、治疗未缓解 组 ＩＬ－６水平高于缓解组和对照组（Ｐ＜ ０． ０１），后两者间无差异（Ｐ＞ ０． ０５），ＩＬ－６与血清游离三 碘甲状腺原氨酸（ＦＴ３）、游离甲状腺素（ＦＴ４）、甲状腺微粒体抗体（ＴｍＡｂ）、甲状腺球蛋白抗体 （ＴｇＡｂ）、骨钙素（ＢＧＰ）呈正相关，与桡、尺骨密度均值（ＢＭＤ）呈负相关。提示ＩＬ－６在ＯＰ发病与骨 代谢中起作用。ＩＬ－６可作为ＧＤ患者治疗效果的判定和预后以及预防骨质疏松症（ＯＰ）发生的重要 指标。     

M1与7TD1细胞中IL-6激活核因子的比较

目的：探讨ＩＬ－６在不同靶细胞中引起不同生物学效应的分子基础。方法：检测ＩＬ－６对Ｍ１与７ＴＤ１细胞生长及分化的影响。通过凝胶阻滞电脉（ＥＭＳＡ）比较ＩＬ－６在Ｍ１与７ＴＤ１细胞中激活ＳＴＡＴ３代表ＪＡＫ－ＳＴＡＴｓ通路）和ＮＦ－ＩＬ０６（代表Ｐ２１ｒａｓ／ＭＡＰＫ／ＮＦＩＬ－６通路）的情况。结果：ＩＬ－６诱导Ｍ１细胞生长停止并向巨噬细胞方向分化,却促进７ＴＤ１细胞生长。在这两种细胞中,低剂量ＩＬ     

干扰素和肿瘤坏死因子调节甲状腺细胞分泌甲状腺球蛋白

采用甲状腺细胞培养方法，研究α－干扰素（ＩＦＮ－α）、γ－干扰素（ＩＮＦ－γ）和肿瘤坏死因子（ＴＮＦ－α）对甲状腺细胞生成甲状腺球蛋白（Ｔｇ）的调节作用。结果显示：在１０＾－３～１０＾３ｕ／ｍｌ的浓度范围内，ＩＦＮ－α、ＩＦＮ－γ及ＴＮＦ－α均可显著抑制甲状腺细胞基础状态下Ｔｇ的分泌；ＩＦＮ－α不影响ＴＳＨ的刺激效应，但ＩＦＮ－γ和ＴＮＦ－α对ＴＳＨ诱导的Ｔｇ释放具有双重调节作用，低浓度时（１０＾     

分泌抗rHuIL－6McAb杂交瘤细胞系的建立及其应用研究

应用常规方法建立了４株稳定分泌抗重组人ＩＬ－６（ｒＨｕＩＬ－６）单克隆抗体（ＭｃＡｂ）的小鼠杂交瘤细胞系１Ｈ３、２Ａ１０、３Ａ３和４Ｂ１。其中，１Ｈ３为ＩｇＧ２ｂ（ｋ），２Ａ１０为ＩｇＧ１（ｋ），３Ａ３和４Ｂ１为ＩｇＧ２ａ（ｋ）。４株ＭｃＡｂ特异性强，与细胞因子ＩＬ－１β、ＩＬ－３、ＩＬ－８、ＴＮＦ－α、ＧＭ－ＳＣＦ、ＩＣＡＭ－１，以及受体菌菌体蛋白成分均无交叉反应。间接ＥＬＩＳＡ测定小鼠腹水ＭｃＡｂ效价为１０（－６）～１０（－８）。应用识别不同表位的ＭｃＡｂ建立了双抗体夹心ＥＬＩＳＡ法检测ＩＬ－６，敏感性为１００ｐｇ／ｍｌ。初步应用表明可用于临床标本的检测。     

分泌抗rHuIL—6McAb杂交瘤细胞系的建立及其应用研究

应用常规方法建立了４株稳定分泌抗重组人ＩＬ－６（ｒＨｕＩＬ－６）单克隆抗体（ＭｃＡｂ）小鼠杂交瘤细胞系１Ｈ３、２Ａ１０、３Ａ３和４Ｂ１。其中，１Ｈ３为ＩｇＧ２ｂ（Ｋ），２Ａ１０为ＩｇＧ１（Ｋ），３Ａ３和４Ｂ１为ＩｇＧ２ａ（Ｋ）。４株ＭｃＡｂ特异性强，与细胞因子ＩＬ－１β、ＩＬ－３、ＩＬ－８、ＴＮＦ－α、ＧＭ－ＳＣＦ、ＩＣＡＭ－１，以及受体菌菌体蛋白成分均无交叉反应。间接ＥＬＩＳＡ测定小鼠腹水ＭｃＡ     

干扰素和肿瘤坏死因子和调节甲状腺细胞分泌甲状腺球蛋白

采用甲状腺细胞培养方法,研究α－干扰素（ＩＦＮ－α）、γ－干扰素（ＩＦＮ－γ）和肿瘤坏死因子（ＴＮＦ－α）对甲状腺细胞生成甲状腺球蛋白的调节作用。结果显示：在１０＾－３－１０＾３ｕ／ｍｌ的浓度范围内,ＩＦＮ－α、ＩＦＮ－γ及ＴＮＦ－α均可显著抑制甲状腺细胞基础状态下Ｔｇ的分泌;ＩＦＮ－α不影响ＴＳＨ的刺激效应,但ＩＦＮ－γ和ＴＮＦ－α对ＴＳＨ诱导的Ｔｇ释放具有双重调节作用,氏深度时（１０＾－３－１     

可溶性syndecan-1 对人多发性骨髓瘤细胞体外的生物学作用

目的：研究可溶性ｓｙｎｄｅｃａｎ－１（ＣＤ１３８）分子对人多发性骨髓瘤（ＭＭ）细胞生长行为的影响及其机制。方法：用亲和层析法分离可溶性ｓｙｎｄｅｃａｎ－１;借助＾３Ｈ－ＴｄＲ掺入、间接免疫荧光、ＡＮＮＥＸＩＮ－Ｖ及ＰＩ标记分析ＭＭ细胞增殖、凋亡周期变化。结果：（１）从ＸＧ－２细胞培养上清中分离纯化得到分子量为６０ｋＤ左右的可溶性ｓｙｎｄｅｃａｎ－１分子;（２）可溶性ｓｙｎｄｅｃａｎ－１分子在体外能抑制ＸＧ－１增殖,阻滞细胞增殖停留在Ｇ２／Ｍ期。并介导其凋亡;ＦＧＦ、５％小牛血清、肝素酶Ⅲ可逆转一定浓度可溶性ｓｙｎ－ｄｅｃａｎ－１的作用,ＨＧＦ、ＶＥＧＦ和ＩＧＦ－１可部分逆转可溶性ｓｙｎｄｅｃａｎ－１分子对细胞的生长抑制作用;（３）ＩＬ－６及激发型抗ＩＬ－６Ｒ１３０（ｇｐ１３０）单抗对可溶性ｓｙｎｄｅｃａｎ－１ｗ     

Interleukin-1 affects the function of cultured human thyroid cells

Cytokines are peptide hormones essential for cellular communication in the immune response. The purpose of this study was to investigate the influence of cytokines, especially recombinant interleukin 1 beta (rIL-1 beta), on human thyroid cells. Thyroglobulin (Tg) was measured by a double antibody radioimmunoassay, and cyclic AMP (cAMP) by a competitive protein binding assay. Supernatants from unstimulated and phytohaemagglutinin-stimulated blood mononuclear cells were added to human thyroid cells cultured in monolayers. A dose-dependent inhibition of the secretion of Tg and cAMP was demonstrated. Both subcultured and primary cultured cells incubated with rIL-1 beta at pharmacological levels (10(-1)-10(2) U/ml) exhibited an inhibition of Tg and cAMP secretion, while at physiological levels (10(-5)-10(-3) U/ml), the secretion of Tg was enhanced. The similar stimulation of cAMP was demonstrated in subcultures. These in vitro studies suggest that IL-1 beta may play a role in the pathogenesis of autoimmune thyroid diseases. Further, the stimulations at low concentrations indicate that IL-1 beta may regulate the function of the thyroid gland under physiological conditions.     

Severe combined immunodeficient (SCID) mice: a model for investigating human thyroid autoantibody synthesis

We have studied the ability of lymphocytes from the blood, thyroid and lymph nodes of patients with autoimmune thyroid disease (AITD) to produce autoantibodies to thyroglobulin (Tg) and/or thyroid peroxidase (TPO) in SCID mice. Human IgG class Tg and/or TPO antibodies were detectable in plasma from SCID mice 7 days after transfer of 15-25 x 10(6) cells/mouse and the highest levels were recorded 2-3 weeks later. In contrast, Tg and/or TPO antibodies were undetectable in recipients of lymphocytes from thyroid antibody negative controls. AITD thyroid lymphocytes produced the most antibody in recipient mice and lower levels were observed in recipients of AITD blood and lymph node lymphocytes. The amounts of Tg and/or TPO antibody detected were in accordance with the ability of thyroid and lymph node lymphocytes to secrete these autoantibodies spontaneously in culture (indicating the presence of cells activated in the patient) and with the capacity of blood lymphocytes (probably B memory cells) to secrete Tg and/or TPO antibodies in culture in response to pokeweed mitogen. Tg antibodies in plasma from SCID recipients of thyroid lymphocytes were of subclasses IgG1, IgG2 and IgG4 and the proportions closely resembled those of the donor's serum Tg antibodies. Blood lymphocytes transferred to SCID recipients were also able to produce Tg antibodies of subclasses 1, 2 and 4 but the subclass distribution varied between mice and the reason for this is not clear at present. Since SCID mice provide an environment in which B lymphocytes from patients with AITD can be activated without mitogen to secrete thyroid antibodies, this model will provide a powerful system for elucidating the mechanisms regulating the secretion of human antibodies to Tg and TPO.     

Characterization of a thyroiditis-inducing thyroglobulin-specific T-cell clone restricted by the H-2 molecule of a low responder mouse strain.

We established a thyroglobulin (Tg)-specific, thyroiditis-inducing T-cell clone, B12G, from B6C3F1 mice by the immunization of mouse Tg with lipopolysaccharide (LPS) from Klebsiella strain LEN (O3:K1). B12G was Thy-1.2+, CD3+, CD4+, CD18+, and CD8-, and could transfer thyroiditis to recipient mice after in vitro stimulation with mouse or bovine Tg. Histological examination showed severe thyroiditis with predominant infiltrations of polymorphonuclear cells; few mononuclear cells were observed. B12G proliferated in response to bovine, mouse, porcine, and rat Tg in the presence of irradiated spleen cells, but did not respond to chicken or human Tg. H-2b, a low-responder haplotype of experimental autoimmune thyroiditis, governed the response of the clone to Tg. B12G produced interleukin-4 (IL-4) and IL-6, but not IL-2 or interferon-gamma (IFN-gamma), on stimulation with mouse Tg. These findings were different from characteristics of previously reported Tg-specific T-cell clones from high-responder mice in terms of epitope specificity and cytokine production pattern, raising the possibility that the specificities and functions of T cells involved in the development of autoimmune thyroiditis in low-responder mice differ from those in high responders.     

Generation of thyroglobulin-specific T-cell clones derived from F1 Fisher rats.

We established T-cell clones from 'poor-responder' Fisher rats specific for thyroglobulin (Tg) with a view to examining Tg presentation by cloned Fisher rat thyroid (FRTL) cells. From the screening of 60 T-cell clones, three high-responding Tg-specific clones (B21.01, B21.04 and B21.05) were isolated from the lymph nodes of F1 generation (Fisher x 'high-responder' Buffalo) female rats immunized with murine Tg in complete Freund's adjuvant (CFA). Three T-cell clones expressed a W3/25+, OX-8- phenotype and responded specifically to murine and rat Tg in T-cell proliferation assays with Fisher rat antigen-presenting cells and secreted IL-2 as measured using a murine cytotoxic T-lymphocyte line (CTLL-2). Both B21.04 and B21.05 T-cell clones were capable of providing helper T-cell function for rat Tg antibody production in syngeneic reconstitution cultures in vitro. In contrast, clone B21.01 inhibited Tg antibody secretion. These data demonstrate that 'poor-responder' Fisher rats are capable of mounting significant T-cell responses to Tg in an F1 generation. Such Tg-specific T-cell clones will allow us to analyse their interaction with cloned Fisher rat thyroid cells and determine the role, if any, of thyroid cell antigen self-presentation to the immune system.     

Cytokines, thyroid autoantibody synthesis and thyroid cell survival in culture

In autoimmune thyroid disease lymphoid cells infiltrating the thyroid gland occur in conspicuous aggregates or as a diffusely distributed population invading the thyroid follicles. Consequently cytokines secreted by activated T cells or macrophages could influence neighbouring thyroid cells as well as other lymphocytes. We have investigated this possibility using recombinant cytokines. Thyroid cell survival was assessed in terms of mitochondrial dehydrogenase activity in monolayers exposed to tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-1 (IL-1 alpha and beta) and interleukin-2 (IL-2) in the presence or absence of thyroid-stimulating hormone (TSH). Neither TNF-alpha nor IL-2 affected thyroid cell survival, IFN-gamma was usually inhibitory and IL-1 alpha slightly enhanced cell survival in some experiments. However, the effects were small and variable and were not enhanced by potentially synergistic combinations of cytokines, longer periods of exposure, or different culture conditions. In contrast, IFN-gamma, IL-2 and TNF-alpha inhibited the ability of thyroid lymphocytes from patients with Graves' disease and Hashimoto's thyroiditis to synthesize autoantibodies to thyroid peroxidase (TPO) and thyroglobulin (Tg). Comparison of lymphoid populations isolated by digestion and/or mechanical disaggregation indicated that a population of activated B cells, plasma cells and T cells, intimately associated with thyroid cells since they could only be extracted by digestion, was influenced by cytokines. Our studies suggest that in addition to its well-recognized ability to induce MHC class II antigens on thyroid cells, IFN-gamma may inhibit thyroid cell proliferation and TNF-alpha, IFN-gamma and IL-2 may down-regulate thyroid autoantibody synthesis.     

Subpopulations of thyroid autoantibody secreting lymphocytes in Graves'' and Hashimoto thyroid glands.

Lymphocytes isolated from Graves' and Hashimoto thyroid tissue by enzymatic (dispase) digestion or mechanical disaggregation were markedly different in terms of their ability to synthesize thyroid autoantibodies in culture. Dispase digestion, followed by removal of thyroid follicular cells, gave a lymphocyte population with a high T:B cell ratio (6:1). However, the ability of these cell suspensions to synthesize microsomal (Mic) and thyroglobulin (Tg) antibodies spontaneously was significantly increased compared with lymphoid suspensions isolated by mechanical means. Spontaneous synthesis of thyroid autoantibodies was not markedly enhanced in cell suspensions prepared from patients' lymph node tissue by digestion compared with mechanical disaggregation. Further, Mic and Tg antibody production by thyroid lymphocytes prepared using dispase was inhibited by pokeweed mitogen (PWM) whereas in most cases suspensions prepared from the same tissues by mechanical dispersion synthesized low or undetectable levels of autoantibodies whether PWM was present or absent. Digestion of tissue debris remaining after mechanical removal of lymphocytes gave suspensions which had an increased proportion of suppressor/cytotoxic T cells compared with suspensions produced mechanically or by digestion alone; however, in terms of spontaneous autoantibody synthesis and PWM induced inhibition, these suspensions were similar to these obtained by digestion alone. It would therefore seem that enzymatic digestion of thyroid tissue resulted in the isolation of a lymphoid population which was different from that extracted by mechanical disaggregation. The digestion process appears to permit the recovery of lymphocytes closely associated with thyroid follicular cells and our studies suggest that it is this population which makes the major contribution to autoantibody synthesis.     

Cytokine actions on the thyroid gland

Cytokines are integral components of the complex intercellular communication required to mount and control an immune response. The purpose of this review is to describe the influence of the most important cytokines on the thyroid gland in animal models and in humans and on isolated thyroid cells. We have used an in vitro system of monolayer cultures of human paraadenomatous thyroid cells for the study of the phenomenological actions of cytokines on the function of the thyrocytes. A biphasic, non-cytotoxic and reversible influence of IL-1 supporting a role of IL-1 in the physiological regulation of thyroid cell function was found. IL-1 in moderate to high concentrations and TNF and IFN-gamma all inhibited thyroid cell function. IL-1 induced release of NO and cGMP from the thyrocytes, but an inhibitor of nitric oxide synthase did not abolish the IL-1-induced inhibition of the release of Tg and cAMP from the TEC. The biochemical pathways by which IL-1 influences thyrocytes are not fully clarified. IL-1 beta inhibited the adenylate cyclase mediated pathways and stimulated the guanylate cyclase mediated pathways, and all the demonstrated IL-1 effects were counteracted by IL-1 ra indicating, that the effects were exerted through activation of specific IL-1 receptors on thyrocytes. The predominant effect of cytokines on the hypothalamic-pituitary-thyroid axis is inhibitory and the cytokines may play a role during physiological as well as pathophysiological conditions contributing to the euthyroid sick syndrome and AITD. A model for the pathogenesis of AITD is outlined. The trigger, of the autoimmune process in AITD is unknown. However, the earliest steps include the interaction between antigen presenting cells and Th cells. In the later phase antigen specific and non-specific immune cells are recruited to the thyroid and an inflammatory infiltrate is built. During this process inflammatory mediators including cytokines, free nitric and oxygen radicals are released. A better understanding of pathogenetic mechanisms is crucial for an appropriate and effective management of AITD, and if possible, for its prevention. Further studies of the actions of these potent agents are one of the keys to a better understanding of the endocrine system both in health and in disease.     

Overexpression of suppressor of cytokine signalling-5 augments eosinophilic airway inflammation in mice

BACKGROUND: Enhanced expression of the suppressor of cytokine signalling (SOCS)-5 might be of therapeutic benefit for T-helper type 2 (Th2) dominant diseases, as its expression is reported to result in a reduction of Th2 differentiation in vitro due to the inhibition of IL-4 signalling. OBJECTIVE: To investigate the regulatory role of SOCS-5 in vivo, we explored the phenotype of an experimental asthma model developed in SOCS-5 transgenic (Tg) mice. METHODS: The SOCS-5 Tg mice or wild-type (WT) mice were sensitized and repeatedly challenged with ovalbumin (OVA). We examined bronchoalveolar lavage fluid (BALF), lung specimens, and airway hyperresponsiveness (AHR) to methacholine. RESULTS: The production of IFN-gamma by CD4(+) T cells from unprimed SOCS-5 Tg mice was significantly increased in comparison with unprimed wild-type mice, indicating that SOCS-5 Tg mice have a Th1-polarizing condition under natural conditions. However, in an asthma model, significantly more eosinophils in the airways and higher levels of IL-5 and IL-13 in BALF were observed in the SOCS-5 Tg than the wild-type mice. AHR in the asthma model of SOCS-5 Tg was also more enhanced than that of wild-type mice. OVA-stimulated CD4(+) T cells from the primed SOCS-5 Tg mice produced significantly more IL-5 and IL-13 than CD4(+) T cells from wild-type mice. CONCLUSION: Our results demonstrate that the overexpression of SOCS-5 does not inhibit Th2 response, but rather augments the phenotype of the asthma model in vivo. This finding throws into question the therapeutic utility of using enhancement of SOCS-5 expression for Th2-dominant disease.