The molecular makeup and function of regulatory and effector synapses

Summary:  Physical interactions between T cells and antigen-presenting cells (APCs) form the basis of any specific immune response. Upon cognate contacts, a multimolecular assembly of receptors and adhesion molecules on both cells is created, termed the immunological synapse (IS). Very diverse structures of ISs have been described, yet the functional importance for T-cell differentiation is largely unclear. Here we discuss the principal structure and function of ISs. We then focus on two characteristic T-cell–APC pairs, namely T cells contacting dendritic cells (DCs) or naive B cells, for which extremely different patterns of the IS have been observed as well as fundamentally different effects on the function of the activated T cells. We provide a model on how differences in signaling and the involvement of adhesion molecules might lead to diverse interaction kinetics and, eventually, diverse T-cell differentiation. We hypothesize that the preferred activation of the adhesion molecule leukocyte function-associated antigen-1 (LFA-1) and of the negative regulator for T-cell activation, cytotoxic T-lymphocyte antigen-4 (CTLA-4), through contact with naive B cells, lead to prolonged cell–cell contacts and the generation of T cells with regulatory capacity. In contrast, DCs might have evolved mechanisms to avoid LFA-1 overactivation and CTLA-4 triggering, thereby promoting more dynamic contacts that lead to the preferential generation of effector cells.     

大鼠肝卵圆细胞的诱导、分离及鉴定

目的建立大鼠肝卵圆细胞的增殖模型,并探索其分离及鉴定方法。方法雄性Wistar大鼠每天1次连续灌胃给予不同剂量二乙酰氨基芴(2-AAF熏5、10、15、20、25mg/kgBW),第5天行标准的2/3肝切除术,术后按各自剂量继续给予11天,不同时间取肝脏组织,行甲胎蛋白、细胞角蛋白18及19染色并观察。以确定的2-AAF最佳剂量制备大鼠肝干细胞增殖模型,Seglen胶原酶原位灌注结合Percoll密度梯度离心分离纯化大鼠肝卵圆细胞,光镜、电镜下观察细胞特点,并进行上述细胞表型标志免疫组化染色。结果2-AAF15mg/kgBW能建立较理想的肝卵圆细胞增殖模型。HE染色可见汇管区及中央静脉周围大量增殖的嗜碱性小细胞,电镜下观察此种细胞具有卵圆形细胞核、细胞质少而淡、核/浆比例较大等特点,免疫组化染色证实甲胎蛋白、细胞角蛋白18和19染色阳性,白蛋白及白细胞共同抗原(LCA)染色阴性。分离所得底层细胞,光镜下表现大小不等、不规则圆形细胞,体积较小,细胞核/浆比例较大,电镜下细胞表面可见少量短而小的微绒毛状突起,余同增殖细胞特点,免疫组化染色与增殖细胞表现相同细胞表型特点。结论本方法可成功诱导、分离、纯化大鼠肝卵圆细胞,符合肝卵圆细胞的形态特点、超微结构及细胞表型标志特点。     

子宮内膜异位症在位内膜腺上皮细胞及基质细胞的分离培养和鉴定

目的 分离培养子宫内膜异位症在位内膜组织中子宫内膜腺上皮细胞及基质细胞,建立研究子宫内膜异位症的细胞模型.方法 对分泌期子宫内膜异位症在位内膜组织用混合酶消化,滤网过滤和差速梯度离心的方法分离,体外培养后通过光镜观察及免疫细胞化学、免疫荧光化学方法对分离细胞鉴定.结果 分离的细胞角质蛋白阳性子宫内膜腺细胞百分率约90～95%;分离的骨架蛋白形成蛋白阳性的基质细胞百分率达90%以上.结论 本研究获得较高纯度的子宫内膜腺细胞和基质细胞,成功建立了研究子宫内膜异位症的细胞模型.     

子宫内膜异位症在位内膜腺上皮细胞及基质细胞的分离培养和鉴定

目的分离培养子宫内膜异位症在位内膜组织中子宫内膜腺上皮细胞及基质细胞,建立研究子宫内膜异位症的细胞模型。方法对分泌期子宫内膜异位症在位内膜组织用混合酶消化,滤网过滤和差速梯度离心的方法分离,体外培养后通过光镜观察及免疫细胞化学、免疫荧光化学方法对分离细胞鉴定。结果分离的细胞角质蛋白阳性子宫内膜腺细胞百分率约90～95%;分离的骨架蛋白形成蛋白阳性的基质细胞百分率达90%以上。结论本研究获得较高纯度的子宫内膜腺细胞和基质细胞,成功建立了研究子宫内膜异位症的细胞模型。     

Hepatocyte progenitors in man and in rodents--multiple pathways, multiple candidates

In severe injury, liver-cell progenitors may play a role in recovery, proliferating, and subsequently differentiating into mature liver cells. Identifying these progenitors has major therapeutic potential for ex vivo pharmaceutical testing, bioartificial liver support, tissue engineering and gene therapy protocols. Potential liver-cell progenitors have been identified from bone marrow, peripheral blood, cord blood, foetal liver, adult liver and embryonic stem cells. Differences and similarities are found among cells isolated from rodents and humans. This review will discuss identifying markers and differentiation potential in in vitro and in vivo models of these putative progenitors in both humans and rodents.     

人外周血初始B细胞和记忆性B细胞亚群的特征和功能

B淋巴细胞是免疫系统的重要免疫成份，主要功能是介导体液免疫应答。在人外周血中，按照B淋巴细胞的发育阶段及功能的不同，可将B淋巴细胞分为初始成熟B细胞、记忆B细胞和浆细胞。记忆B细胞又可分为IgM记忆B细胞和类型转换的记忆B细胞。近年来的研究表明，B淋巴细胞的亚群远比人想象中的复杂，因此对人B细胞各亚群的起源、发育和功能进行更深入的研究，将有助于治疗自身免疫性疾病，在慢性感染性疾病的治疗过程中找到新的策略，并指导研发安全有效的疫苗。     

Harnessing innate and adaptive immunity for adoptive cell therapy of renal cell carcinoma

The development of immunotherapies for renal cell carcinoma (RCC) has been the subject of research for several decades. In addition to cytokine therapy, the benefit of various adoptive cell therapies has again come into focus in the past several years. Nevertheless, success in fighting this immunogenic tumor is still disappointing. RCC can attract a multitude of different effector cells of both the innate and adaptive immune system, including natural killer (NK) cells, γδ T cells, NK-like T cells, peptide-specific T cells, dendritic cells (DC), and regulatory T cells (Tregs). Based on intensive research on the biology and function of different immune cells, we now understand that individual cell types do not act in isolation but function within a complex network of intercellular interactions. These interactions play a pivotal role in the efficient activation and function of effector cells, which is a prerequisite for successful tumor elimination. This review provides a current overview of the diversity of effector cells having the capacity to recognize RCC. Aspects of the functions and anti-tumor properties that make them attractive candidates for adoptive cell therapies, as well as experience in clinical application are discussed. Improved knowledge of the biology of this immune network may help us to effectively harness various effector cells, placing us in a better position to develop new therapeutic strategies to successfully fight RCC.     

B cell maturation and selection at the marrow-periphery interface

More than 95% of newly formed B cells die in the short interval spanning slgM acquisition in the bone marrow and entry into the long-lived pool, suggesting that selective events dictating B cell longevity occur at this stage. These likely include both ligandinduced deletion as well as discrete events that mediate recruitment to the long-lived recirculating pool. We are probing these events through the examination of normal B cell differentiation during this critical period: the characterization of a natural mutation that blocks late maturation, an irradiation/autoreconstitution model of marrow-derived B cell differentiation, and the identification of life span regulatory genes whose expression changes within this window.     

T细胞与类风湿性关节炎

类风湿性关节炎(RA)是一种慢性、炎症性自身免疫性疾病,发病机制非常复杂,至今尚未阐明.尽管多种免疫细胞和分子被证实参与了RA的关节炎症反应和组织破坏,但抗原特异性T细胞的激活始终被认为是RA发病起始和进展的中心环节.不同亚群T细胞在RA发病中发挥不同作用,以往认为,自身抗原诱导的促炎性Th1细胞活化是RA发病的主要因...     

Fate mapping and scRNA sequencing reveal origin and diversity of lymph node stromal precursors

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3株弥漫大B细胞淋巴瘤细胞系的鉴定与临床病理相关分析

目的鉴定OCI-Ly1、OCI-Ly8、OCI-Ly103株弥漫大B细胞（diffuselargeB-celllymphoma,DLBCL）,并进行分子亚类分型及临床病理相关分析。方法采用细胞块切片HE染色观察细胞形态,运用CD3、CD20、CD10、Bcl-6、MUM-1抗体进行免疫标记确定其分子亚类;MTT法测定细胞的增殖活力。结果 OCI-Ly1和OCI-Ly8细胞形态以中心母细胞为主,OCI-Ly10以免疫母细胞为主。3株细胞CD20和CD10均弥漫阳性,CD3阴性。OCI-Ly1个别细胞Bcl-6阳性,MUM-1阴性;OCI-Ly8细胞Bcl-6、MUM-1均阴性;OCI-Ly10个别细胞Bcl-6阳性,MUM-1散在或簇状阳性,CD10和MUM-1的表达具有互补现象,在36例DLBCL临床病理标本中发现有7例（19%）CD10和MUM-1表达互补。OCI-Ly10增殖能力显著高于OCI-Ly1、OCI-Ly8（P〈0.001）。结论 OCI-Ly1和OCI-Ly8属于GCB型,OCI-Ly10属于NC型（non-classfied）;OCI-Ly10细胞系及组织标本CD10和MUM-1的表达互补现象有待进一步研究。     

Dividing cellular asymmetry: asymmetric cell division and its implications for stem cells and cancer

Cell division is commonly thought to involve the equal distribution of cellular components into the two daughter cells. During many cell divisions, however, proteins, membrane compartments, organelles, or even DNA are asymmetrically distributed between the two daughter cells. Here, we review the various types of asymmetries that have been described in yeast and in animal cells. Asymmetric segregation of protein determinants is particularly relevant for stem cell biology. We summarize the relevance of asymmetric cell divisions in various stem cell systems and discuss why defects in asymmetric cell division can lead to the formation of tumors.     

Granular cells in odontogenic and non-odontogenic tumours

Summary Granular cells can occur in various odontogenic and non-odontogenic tumours. 5 granular cell lesions, one granular cell ameloblastoma, one so-called granular cell ameloblastic fibroma and three granular cell tumours were examined immunohistochemically for the intermediate filaments cytokeratin, vimentin, desmin, neurofilaments and the neural markers NSE and S-100 protein. The granular cell tumors (granular cell myoblastoma) showed positive staining for vimentin and S-100 protein. Only vimentin could be demonstrated in the granular cells of the so-called granular cell ameloblastic fibroma, whereas the granular cell ameloblastoma showed positive staining only for cytokeratin. A positive reaction with S-100 protein was not found in any of the odontogenic tumours. In our opinion the mesenchymal odontogenic granular cell is a fibroblast, whereas the epithelial granular cell is derived from enamel epithelium. The term granular cell ameloblastic fibroma is a misnomer, as a number of these tumours are probably central odontogenic fibromas exhibiting granular cell transformation.     

两种不同纯度的嗅鞘细胞在体外存活与生长的比较

比较80%和50%两种纯度的嗅鞘细胞在体外培养条件下的存活与生长,为嗅鞘细胞体内移植选用最佳纯度提供依据。分离、培养并纯化成年SD大鼠嗅鞘细胞,将纯化的嗅鞘细胞和收集到的贴壁成纤维细胞进行约80%和50%的比例混合后接种,继续培养1d或3d。所有细胞于不同时间点行P75免疫细胞化学荧光染色,以鉴定嗅鞘细胞的初始及其后培养过程中数量和纯度的变化。观察细胞状态,计数细胞总数和P75免疫阳性细胞数目,求得各组嗅鞘细胞数量和纯度并行统计学分析。结果显示:两种不同纯度嗅鞘细胞在培养1d时形态正常,3d时纯度为50%的嗅鞘细胞胞体依然饱满,突起更加纤长,数量和纯度亦无明显下降。而纯度为80%的嗅鞘细胞在培养3d时已出现胞体萎缩和突起变短,数量从1d时每一观察区域内的35±13显著下降为23±5(P=0.02),但纯度未发生明显变化。结果表明50%纯度嗅鞘细胞的存活及生长状态优于80%者,提示细胞体内移植时应考虑选取50%纯度的嗅鞘细胞。     

Banks, Repositories and Registries of Stem Cell Lines in Europe: Regulatory and Ethical Aspects

To overview banks, repositories and registries of stem cell lines in Europe excluding bone marrow and cord blood banks; to concisely discuss the most important scientific, regulatory and ethical aspects of stem cell banking in a manner understandable to a layperson, but remain detailed enough not to compromise thoroughness of information. Review of scientific publications, laws and ethical guidelines in this field up through September 2008; hearing the opinions of key persons working in stem cell banking. The article discusses the procedure of stem cell banking and related safety issues and reviews the regulation of stem cell banking at the regional (European) and the national level. Stem cell banking can help meet scientific and certain ethical imperatives, but is complicated in the context of heterogeneous laws, guidelines, and ethical standards. In the pluralistic European society with cultural diversity leading to heterogeneous laws, harmonisation of international guidelines and national laws regulating stem cell banking is needed, as well as mapping of implementation at the national level.

肿瘤干细胞与卵巢癌

卵巢肿瘤干细胞（OCSCs)是存在于卵巢癌组织中的一类具有自我更新和多向分化潜能的细胞,表面共表达CD44和CD117分子标记。虽然其起源不是很确定,但目前倾向于认为卵巢表面上皮细胞来源于OCSCs。研究OCSCs自我更新机制和表观遗传学的改变,可为肿瘤发生的机制及新药的开发提供很好的基础     

Th17细胞与Th1、Treg细胞关系的研究进展

CD4~+T细胞在不同细胞因子环境中可分化为Th1、Th2、Treg、Th17四种亚群,在一定条件下,各Th细胞亚群之间可以互相转化,从而使机体的免疫效应和免疫抑制处于精细而复杂的平衡状态。Th17细胞与自身免疫性疾病和肿瘤的发生发展关系密切,研究Th17细胞与Th1细胞、Treg细胞之间的相互关系,对于预防和治疗自身免疫性疾病和肿瘤等临床难题意义重大。     

Granular cell basal cell carcinoma. Light microscopy,immunohistochemical and ultrastructural study

Summary Granular cell basal cell carcinoma (BCC) is a rare histological variant of BCC. In this, the fifth reported case, a 67-year-old male with BCC located on the nose, light microscopy examination showed a tumour with the classical configuration of nodular BCC, in which most cells had finely granular eosinophilic cytoplasm. Ultrastructural observation showed numerous lysosome-like granules filling the cytoplasm of tumour cells, along with numerous well-formed pentalaminate desmosomes. Immunohistochemical profile (including positivity for keratins C 5.2 and AE 1 and for Leu-M1), together with the presence of cytoplasmic tonofilament bundles and desmosomes, are consistent with the proposed epithelial origin of granular cells in this tumour.