HLA-G与T细胞

人类白细胞抗原G(human leukocyte antigen-G,HLA-G)属于非经典的HLAⅠ类分子,是机体内一种重要的免疫耐受分子。T细胞是细胞免疫的主要效应细胞,在机体维持免疫稳态中发挥重要作用。近来研究发现,HLA-G对T细胞的免疫调节功能一方面依赖于T细胞上抑制性受体直接发挥免疫抑制作用,另一方面通过诱导或"胞啃"机制产生调节性T细胞(Treg)、HLA-G+T细胞间接参与机体免疫耐受。本文就HLA-G对T细胞调节功能的研究进展作一综述。     

HLA-G调控自然杀伤细胞免疫功能的研究进展

人白细胞抗原G(HLA-G)属于非经典的HLAⅠ类分子,正常情况下主要表达于母胎界面绒毛外滋养层细胞。一些肿瘤细胞系、肿瘤组织、感染的组织细胞及正常组织细胞也可检测到HLA-G的表达。自然杀伤(NK)细胞是重要的固有免疫细胞,在免疫应答与免疫调节过程中发挥重要作用。HLA-G参与免疫调控引发了越来越多的关注,其功能由最初的"母胎耐受"逐渐扩展到肿瘤免疫逃逸、器官移植耐受等多个方面,本文重点回顾了HLA-G参与调控NK细胞免疫功能的各种机制:通过与受体相互作用抑制NK细胞的杀伤作用、调节NK细胞表面受体及细胞因子的表达、通过胞啃作用(trogocytosis)广泛引发免疫抑制、引发NK细胞凋亡。     

人类白细胞抗原G 参与免疫调节研究进展

人类白细胞抗原G(HLA-G)是一种非经典的人类主要组织相容性复合物(MHC)Ib类分子,是机体内重要的免疫耐受分子,有助于免疫逃逸或免疫细胞无能。HLA-G可限制性表达,生理条件下,HLA-G分布于免疫豁免组织细胞上,但在肿瘤及病毒感染等病理状态下,HLA-G在相应组织细胞上可获诱导性表达。因此,HLA-G的功能可能是有益的,因为当妊娠或移植时,HLA-G可保护其免受机体免疫系统伤害;同时,HLA-G也是有害的,因为它的免疫耐受功能同样可以被肿瘤或者病毒利用,从而保护它们免受机体的攻击,造成对机体的危害。近年来,人们对HLA-G参与免疫调节进行了大量研究,本文就HLA-G在移植和肿瘤免疫耐受方面作一综述。     

HLA-G与NK细胞

自然杀伤细胞(natural killer,NK)是天然免疫系统的主要效应细胞,是机体抵抗肿瘤和病毒感染的第一道防线。人类白细胞抗原-G(human leukocyte antigen-G,HLA-G)属于非经典的HLAⅠ类分子,是机体内一个重要的免疫耐受分子。HLA-G抗原对NK细胞的免疫调节功能一方面是依赖于一系列杀伤细胞免疫球蛋白样受体,另一方面是通过调节NK细胞多种趋化因子受体表达。本文就HLA-G对NK细胞调节功能的研究进展作一综述。     

085 HLA-E

人MHCⅠ类基因分两类经典的Ia基因(包括HLA-A、HLA-B、HLA-C)和非经典的Ib基因(主要包括HLA-E与HLA-G、HLA-F)。3种非经典MHC Ⅰ类基因位于相同的染色体区域6P21.3，不同于经典分子，具有特异性的转录、蛋白表达和免疫作用。1988年发现HLA-E具有有限的多态性，作为先天的和后天的免疫统的一部分，它有非常重要的免疫调节作用，本文拟就有关问题作一综述。     

HLA-G与移植免疫研究进展

人类白细胞抗原G(human leucocyte antigen G,HLA-G)是机体内一种重要的免疫耐受分子。HLA-G分子通过直接与免疫细胞上的抑制性受体结合或间接诱导产生HLA-G依赖性调节性细胞,改变细胞因子表达谱,从而调节机体的免疫状态。随着研究的深入,HLA-G分子生物学功能及临床意义从最初的母胎免疫耐受延伸至肿瘤免疫,感染免疫和移植免疫等研究领域。本文就HLA-G在移植免疫中的表达意义及临床应用等相关研究进展作一综述。     

HLA-G研究进展

HLA-G分子属MHC Ⅰ类非典型分子(MHC Ⅰb),组织特异性地高表达于胎母界面的滋养层细胞,MHC Ⅰ、Ⅱ类抗原是缺乏的。HLA-G分子通过NK细胞受体抑制NK细胞杀伤活性,并作为CD8~+细胞毒抑制性T细胞的识别和激活因子,抑制CTL的杀伤作用,HLA-G在胎母耐受中发挥重要作用。     

HLA-G 对子痫前期发生发展的影响

子痫前期(PE)是一种常见的妊娠特有并发症,其病因及发病机制与免疫因素有关,而人类白细胞抗原G(HLA-G)在母胎免疫调节中发挥重要作用。HLA-G具有启动子独特性及限制多态性两种基因特性,胎儿滋养细胞HLA-G分子低表达是介导PE发生的关键环节,可能由细胞胞啃机制受阻、获取HLA-G能力下降所致,继而通过Th1/Th2平衡向Th1偏移、滋养细胞浸润能力受损,造成胎盘浅着床和子宫螺旋动脉重铸不足,促进PE的发生发展。     

HLA-G研究进展及与肿瘤的相关性

HLA-G属于非经典的HLA-Ⅰ类分子，特异性表达于母胎界面，对于维持人类正常妊娠有重要作用。在肿瘤细胞的异位表达，引起肿瘤细胞逃避宿主免疫监视日益受到重视。本就HLA-G基因结构、多态性、分布、免疫功能等方面的最新研究进展及与肿瘤的相关性作一综述。     

HLA-G与HIV病毒感染的研究进展

影响和干预人类白细胞抗原(HLA)在宿主细胞表面表达是病毒逃避机体抗病毒免疫的重要途径之一。人类白细胞抗原G(HLA-G)是机体内一个重要的免疫耐受分子,多种病毒感染后均可诱导HLA-G分子的表达,促进病毒的免疫逃逸。在人类免疫缺陷病毒(HIV)感染过程中,HIV可通过多种机制诱导HLA-G分子在单核细胞、T淋巴细胞表面的异常表达及分泌大量可溶性HLA-G(sHLA-G)。HIV诱导表达的HLA-G分子与其受体结合,通过直接抑制NK细胞、T淋巴细胞等免疫细胞的生物学活性或间接诱导HLA-G+Treg发挥免疫抑制功能,使HIV病毒有效逃避宿主的免疫监视及攻击。本文就HLA-G结构、受体、基因多态性与HIV易感性、HIV感染与HLA-G分子异常表达,和HLA-G对免疫细胞的影响等作一综述。     

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.     

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.     

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.     

What will studies of Fulani individuals naturally exposed to malaria teach us about protective immunity to malaria?

There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.     

'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.     

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.     

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.     

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.