CD28协同刺激分子对T细胞受体介导的胸腺细胞亚群凋亡的影响

目的：分析anti-TCRαβmAb anti-CD28mAb诱导小鼠胸腺淋巴细胞不同亚群的凋亡及凋亡程度，分析CD28协同刺激分子对TCR受体介导的胸腺细胞亚群凋亡的影响。方法：新鲜分离胸腺细胞，加入anti-TCRαβmAb-anti-TCRαβmAb anti-CD28mAb等培养20h，进行多重染色，流式细胞仪分析。结果：与胸腺细胞自发凋亡的结果相比较；（1）双信号刺激可明显增加胸腺细胞凋亡的数目，尤其是CD4^ CD8^ 胸腺细胞的凋亡数目。（2）凋亡的CD4^ CD8^ 亚群，CD4^ CD8^-亚群细胞表面CD28的表达均增多。结论：CD28共刺激分子对TCR受体介导的胸腺细胞亚群凋亡的影响与细胞的成熟程度有关，CD28共刺激分子能明显增强不成熟皮质胸腺细胞的凋亡。     

流式细胞术测定淋巴细胞的分裂

为确立流式细胞仪检测淋巴细胞的分裂的新方法 ,利用CFSE标记新鲜分离外周及胸腺淋巴细胞后 ,加入PMA、ConA、抗TCR抗体等培养 3d ,染色进行FACS分析。结果 ,诱导T细胞活化分裂的 3种刺激剂 ,以PMA刺激作用最强 ,ConA次之 ,抗TCR抗体最弱。表明CFSE标记细胞 ,流式细胞仪分析法不仅可以检测单细胞水平上细胞的分裂 ,还可根据荧光强度判断细胞的分裂次数。     

小鼠CD^3＋TCRαβ^＋CD^—CD8^—胸腺细胞特性分析

目的：分析CD^3 TCRαβ^ CD^-CD8^-胸腺细胞的特性，推断其在胸腺发育中表型和功能的成熟过程。方法：分离纯化小鼠胸腺DN细胞，用多重染色的方法分析CD^3 TCRαβ^ CD^-CD8^-细胞的表型和TCR库，并与外周淋巴结的相应细胞进行对比。结果：DNA胸腺细胞为异质性细胞，包括CD3^-DN细胞和CD3^ DN细胞，而CD3^ DN细胞又分为CD^3 TCRαβ^ 和CD3^ TCRγδ^ 2个亚群。其中，CD^3 TCRαβ^ DN细胞体积较小，绝大部分细胞对可的松耐受，细胞中能与自身反应的Vβ^3 和Vβ11^ 细胞比例极低，表型较为成熟，与髓质型SP（single positive) 细胞相似。结论：CD^3 TCRαβ^ DN细胞不同于CD^3 TCRαβ^－DN细胞，是一个独特的细胞亚群，只有在经历表型和功能的进一步成熟才能迁出胸腺，移至外周。     

年龄、性别在幼鼠胸腺T细胞增殖中的作用

目的：分析年幼小鼠性别、年龄与CD3、CD4、CD8免疫参数表达的关系。方法：分离3—9周小鼠胸腺、脾脏T淋巴细胞，FACS分析细胞表面CD3、CD4、CD8的表达；CFSE标记后细胞，加入ConA、抗TCR抗体、PMA IONO刺激剂培养72小时，流式细胞仪分析的方法比较不同刺激剂作用下雌、雄小鼠T细胞的增殖。结果：结果胸腺和脾脏表面CD3、CD4、CD8的表达与性别无明显关系，6-9周小鼠脾脏CD3^ 细胞明显多于3—4周小鼠；胸腺细胞的增殖与年龄、性别无关，而3周雌性小鼠脾细胞对PMA IONO刺激后的增殖应答比雄性明显，4-6周雄性小鼠脾细胞的增殖能力强于雌性小鼠，7—8周雌性小鼠脾细胞对抗TCR抗体的应答能力明显减小。结论：免疫系统的雌雄异型可能早于青春期。     

超抗原SEB激活诱导CD4~+T细胞凋亡模型的建立

目的为了探讨超抗原活化诱导 CD4+ T淋巴细胞凋亡分子机理及其信号传导途径 ,有必要建立超抗原活化诱导 CD4+ T细胞凋亡模型。方法采用电镜观察细胞凋亡的形态学特征 ,借助流式细胞仪 PI染色观察细胞凋亡的光散射特征及亚二倍体核型峰特征 ,琼脂糖凝胶电泳分析细胞凋亡的 DNA片段化图谱 ,最后采用改进的二苯胺 (DPA)法定量分析细胞凋亡 DNA片段化百分率。结果 4μg/ m L SEB刺激静息的 SEB应答 CD4+ T细胞 12 h后 ,电镜下观察呈现典型的凋亡形态学特征 ;流式细胞仪 PI染色分析表明 ,在二倍体峰的左侧出现亚二倍体核型峰典型凋亡特征 ,在光散射图谱上呈现低于正常细胞的前向散射和高于正常细胞的侧向散射 ;琼脂糖凝胶电泳分析呈现典型的凋亡 DNA梯状图谱 ;DNA片段化百分率分析表明 ,超抗原 SEB活化诱导 CD4+ T细胞凋亡率的升高具有时间依赖性 ,添加 Fas- Ig融合蛋白能够特异性抑制凋亡 DNA片段化百分率的升高。结论超抗原 SEB活化诱导 CD4+ T细胞凋亡模型的建立 ,为进一步深入探讨超抗原活化诱导 T细胞死亡的分子机理和信号通路奠定了坚实基础     

脐血CD34+细胞体外定向诱导分化为T淋巴细胞的实验研究

目的：建立利用人造血干／祖细胞体外定向诱导分化为T淋巴细胞的方法，为研究T细胞生物学特性及细胞免疫提供技术平台。方法：MACS方法分离人脐带CD34^ 细胞接种到人胎儿胸腺基质单层细胞上，IMDM液体培养基含20％人AB血清并加入FL、IL-12、IL-7和IL-2细胞因子组合，于培养7、14、21、28、35、42天取非贴壁细胞利用流式细胞仪对细胞表型进行检测，并进行细胞形态学分析。结果：2周后，CD4^ CD8^ 非成熟T淋巴细胞占细胞总数的0．3％-13．3％，4-5周CD4^ CD8^ T淋巴细胞达到高峰占16．6％-26．5％，且CD3^ CD4^ CD8^ 和CD3^ CD4^-CD8^ T淋巴细胞逐渐增多，6周后达26．5％～64．9％和11．6％-38．9％。培养成熟的T淋巴细胞经PHA IL-2刺激后瑞氏染色鉴定可见大原始淋巴细胞存在。结论：利用人脐血CD34^ 在体外人胎儿胸腺基质单层细胞上加FL、IL-12、IL-7和IL-2细胞因子组合条件下，可诱导分化出T淋巴细胞，并且培养的T细胞对有丝分裂素刺激有增殖反应。     

siRNA介导的IBP表达抑制对 T细胞凋亡的影响

目的 研究IBP表达抑制后对T细胞凋亡产生的影响.方法 构建IBP siRNA稳定表达及阴性对照载体,脂质体法转染Jurkat T细胞,G418筛选稳定转染细胞株,用anti-CD3和CD28 mAb刺激介导的TCR信号方式作用于稳定转染细胞后,以3H-TdR掺入实验检测细胞增殖,Annexin-v/PI双参数法经流式细胞仪检测细胞凋亡.结果 TCR信号刺激下,阴性对照组细胞的3H-TdR掺入量在24h时下降为未刺激对照组的67%,随时间延长其下降更显著,且24h发生明显凋亡,凋亡率为21.96%;IBP siRNA表达载体转染细胞在不同时相点的增殖均不受影响,24h凋亡率仅为2.12%,比阴性对照组细胞显著降低.结论 IBP缺失能使TCR信号刺激下的细胞激活后凋亡受到抑制,提示IBP可能参与T细胞免疫自稳状态的调节.     

NOD小鼠胸腺细胞TCR介导的信号通路缺陷

目的 进一步研究NOD小鼠T细胞应答改变机理。方法 用抗TCR抗体、ConA激活NOD小鼠胸腺细胞，分析TCR介导的信号通路的水平。结果 与Balb／c小鼠胸腺细胞相比，抗TCR抗体诱导的增殖应答较弱，与年龄及NOD胸腺CD4^ CD8^-和CD4^-CD8^ SP细胞有关；rIL-2能部分恢复对TCR抗体应答的缺乏。NOD小鼠对PMA IONO和PMA anti—TCR-mAb应答正常，但对anti-TCRmAb IONO应答缺乏。结论 与年龄有关的NOD小鼠胸腺细胞对TCR抗体应答的缺乏与T细胞激活时上游PKC信号通路的缺乏有关。     

SEB诱导的CD4+ T细胞无能、凋亡及MHC-I类分子表达下调

目的：探讨超抗原金黄色葡萄球菌肠毒素（SEB）体外诱导外周T细胞免疫耐受的作用机制。方法：采用SEB体外刺激C57BL/6J（B6）小鼠的脾细胞后，以MTT比色法检测脾细胞的增殖，并用PI染色后以流式细胞术（FCM）分析不同时间段处于S期，G0-G1期的细胞及无能T细胞的凋亡，测定T细胞亚群及MHC-I（H-2K^b)表达的变化。用琼脂糖凝胶电泳，观察不同时间段凋亡T细胞的DNA特征。结果：部分去除CD8^ T细胞后。SEB可刺激B6小鼠脾细胞中CD4^ T细胞大量增殖，在SEB刺激后第3天，CD4^ T细胞中处于S期的比率最大，此后开始下降；而处于G0-G1期的CD4^ T细胞变化则相反，在初次刺激后第3天，增殖的CD4^ T细胞出现无能，FCM检测及用琼脂糖凝胶电泳检查DNAladder证实，在第7天，无能CD4^ T细胞出现凋亡，且凋亡细胞的比率逐渐增多，不因加入抗CD3抗体或CoN A而逆转，在SEB刺激后，CD4^ T细胞表面MHC-I类分子（H-2K^b)的表达，随细胞无能的出现而明显下调。结论：SEB诱导的T细胞免疫耐受，可能与CD4^ T细胞的无能，凋亡及细胞表面分子MHC-I的表达下调有关。     

TCR抗体诱导不成熟胸腺细胞亚群凋亡的敏感性研究

为比较小鼠不同胸腺细胞亚群对抗TCR抗体诱导凋亡的敏感性，用体外抗TCR抗体刺激分离胸腺细胞．BALB／c小鼠体内注射抗TCR抗体，FACS检测胸腺细胞。结果显示，CD4^ CD8^ DP胸腺细胞和CD4^-CD8^ CD3^-TCR-细胞对抗TCR抗体诱导的凋亡敏感，但CD4^-CD8^-CD3^-TCR-胸腺前体细胞自发凋亡率低，且抗TCR抗体诱导的凋亡．表明胸腺细胞对凋亡的敏感点产生于CD4^-CD8^ CD3^-TCR-细胞表达后，胸腺细胞的凋亡敏感性受发育调节。     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc² (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.     

Renal dysplasia and asplenia in two sibs

A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for $\text{primates}$. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.     

HLA in North Colombia Chimila Amerindians

HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.     

The case for allele‐specific recognition by the TCR

There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.     

The universal muscular chamber. A basic unit of the genitourinary, cardiovascular, gastro-intestinal, skeletal, cutaneous, respiratory and other systems, endocameral hypertension; and spasm, the key to their idiopathic diseases and arthropathies

Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.