神经营养在小鼠脾的定位研究

为了解神经营养素与免疫系统的关系，用免疫组织化学方法对神经营养素包括神经生长因子，脑源性神经营养因子，神经营养素进行小鼠脾的定位研究。结果表明：３种神经营养素的免疫反应存在于脾内，但分布特点各不相同ＧＮＦ主要分布于白髓动脉周围淋巴鞘外层，边缘区和红髓的巨噬细胞样和巴细胞样细胞，ＢＤＮＦ除具有ＮＧＦ相似的分布特点外，还见于脾淋巴小结生发中心的淋巴细胞细胞；ＮＴ－３则存在于白、红髓的网状细胞样细胞。这     

免疫应答中小鼠脾GAP-43神经支配的可塑性--神经纤维数量和分布的变化

为了解脾交感神经在免疫功能增强时的形态变化，用免疫组织化学方法观察了ＢＡＬＢ／ｃ小鼠脾内生长相关蛋白样免疫反应（ＧＡＰ－４３－ＬＩ）性神经在结核菌素衍生蛋白（ＰＰＤ）诱发的免疫反应高峰期数量和分布的变化。结果显示，动物在接受两次ＰＰＤ注射（２１ｄ＋７ｄ）后，脾ＧＡＰ－４３－ＬＩ神经纤维密度明显增加并伴有分布和形态的变化。于对照动物，脾ＧＡＰ－４３－ＬＩ神经纤维主要分布于血管周围，少量伸入动脉周围淋巴鞘的脾基质中，而在免疫刺激的动物，不仅血管周围的神经纤维明显增多，动脉周围淋巴鞘外层、边缘区和红髓等免疫应答活跃的部位也出现许多神经纤维。神经纤维分支和纤维上膨体明显增多。以上结果提示：免疫应答中脾神经成分发生活跃的结构重塑，这些变化有可能与神经的免疫调节功能有关。     

神经胶质生长因子研究进展

神经胶质生长因子研究进展顾继杰（中国医学科学院基础医学研究所生物化学及分子生物学研究室，北京１００００５）自从第一个神经生长因子ＮＧＦ发现以来，最近几年又陆续发现了ＢＤＮＦ、ＣＮＴＦ、ＮＴ－３、ＮＴ－４及ＮＴ－５等许多神经营养因子［１］。人们的注意力...     

痢疾菌苗滴鼻免疫小鼠诱导不同部位淋巴组织的免疫应答

目的 探讨痢疾菌苗滴鼻免疫后，小鼠不同粘膜部位和其它部位免疫应答的影响。方法将Ｂａｌｂ／ｃ小鼠随机分为３组，每组１５只。舰疾菌苗株 ＴＩＭ－２１１７或 ＦＳ－５４１６，按 ５×10～6、１×１０～７、４×１０～７和４×１０～７ＣＦＵ／只滴鼻跟 Ｂａｌｂ／ｃ小鼠４次涧隔两 ｗｂ。分离鼻相关淋巴组织（ＮＡＬＴ）、鼻通道（ＮＰ）及脾、小肠的ＰＰ结淋巴细胞。一部分细胞采用流式细胞术检测淋巴细胞表型的变化；另一部分细胞与全菌破碎抗原共培养，于不同时间点取出，提取ＲＮＡ做ＲＴ－ＰＣＲ。结果两株菌苗经鼻内免疫后，ＮＡＬ、ＮＰ和ＰＰ结的淋巴细胞中ＣＤ３Ｔ细胞显著增加，其中以ＣＤ４＋Ｔ细胞增加为主。ＴＳＭ－２１１７株免疫组的脾细胞中，Ｂ２２０＋细胞显著增加；而ＦＳ－５４１６株免疫组的脾细胞中，ＣＤ３＋Ｔ细胞显著增加。免疫小鼠的ＮＡＬＴ、ＮＰ和ＰＰ结淋巴细胞，在体外经抗原刺激后，均在不同时间出现ＩＦＮ－γ和ＩＬ-４ｍＲＮＡ的表达，ＴＧＦ－β ｍＲＮＡ的表达在免疫前后无明显变化。结论痢疾菌苗经鼻粘膜免疫，可诱导不同粘膜部位及全身免疫应答的产生。     

对神经营养素的新认识

神经营养素家族（ＮｅｕｒｏｔｒｏｐｈｉｎｓＮＴｓ），已知有ＮＧＦ、ＢＤＮＦ、ＮＴ—３、ＮＴ４／５、ＮＴ—６几种，它们的生物学效应非常广泛：促神经元存活、分化，调控神经元功能还与神经元可塑性相关。近来实验结果表明，ＮＴｓ的促存活涉及细胞程序性死亡，ＮＴｓ、肽类、递质以及激素四者相互作用调控神经细胞的活动。另外，它们的生物学效应又往往交叉，本文还概括了对其作用专一性方面的一些认识。     

HIV—1gp120基因及其与IFN—α基因共表达产物的构建和 …

目的 研究细胞因子ＩＦＮ－α在机体免疫应答过程中的免疫佐剂效应。方法 以表达中国流行株ＨＩＶ－１ｇｐ１２０基因的核酸疫苗质粒ｐＧＰ及共表达中国流行株ＨＩＶ－１ｇｐ１２０基因与ＩＦＮ－α基因的核酸疫苗质粒ｐＧＰＩＦＮ－α免疫Ｂａｌｂ／ｃ鼠，用流式细胞仪测定１００００个免疫鼠脾淋巴细胞中ＣＤ４＾＋，ＣＤ８＾＋Ｔ细胞数及ＣＤ４＾＋／ＣＤ８＾＋比值。结果 ｐＧ－ＰＩＦＮ－α与ｐＧＰ比较，ｐＧＰＩＦＮ－α免     

血小板源生长因子—B及其受体在哮喘豚鼠气道中的表达

为探讨血小板源生长因子－Ｂ多肽（ＰＤＧＦ－Ｂ）在哮喘发病中的作用，应用免疫组织化学方法，检测了豚鼠哮喘模型气道及肺组织中ＰＤＧＦ－Ｂ多肽及其受体（ＰＤＧＦＲ－β）的表达。结果表明：实验组气道壁及周围组织有大量ＰＤＧＦ－Ｂ多肽阳性细胞，主要为气道上皮细胞及浸润的炎症细胞。ＰＤＧＦＲ－β阳性细胞主要分布在气道基底膜及周围结缔组织，偶见于平滑肌和肺间质。提示ＰＤＧＦ－Ｂ多肽及ＰＤＧＦＲ－β的表达与哮喘发     

脑源性神经营养因子研究现状

本文主要综述了脑源性神经营养因子（ｂｒａｉｎ－ｄｅｒｉｖｅｄｎｅｕｒｏｔｒｏｐｈｉｃｆａｃｔｏｒ，ＢＤＮＦ）的发现、生化特性、与神经生长因子（ＮＧＦ）和神经营养因子Ⅱ（ＮＴ－３）属于同一基因家族以及靶源性等概念：总结了脑源性神经营养因子对运动神经元、胆碱能神经元、多巴胺神经元及感觉等其它神经元的效应作用，并展望了应用脑源性神经营养因子治疗运动神经元病变及老年神经系统退行性疾病的前景。     

血小板源生长因子-B及其受体在哮喘豚鼠气道中的表达

为探讨血小板源生长因子－Ｂ多肽（ＰＤＧＦ－Ｂ）在哮喘发病中的作用，应用免疫组织化学方法，检测了豚鼠哮喘模型气道及肺组织中ＰＤＧＦ－Ｂ多肽及其受体（ＰＤＧＦＲ－β）的表达。结果表明：实验组气道壁及周围组织有大量ＰＤＧＦ－Ｂ多肽阳性细胞，主要为气道上皮细胞及浸润的炎症细胞。ＰＤＧＦＲ－β阳性细胞主要分布在气道基底膜及周围结缔组织，偶见于平滑肌和肺间质。提示ＰＤＧＦ－Ｂ多肽及ＰＤＧＦＲ－β的表达与哮喘发病关系密切。     

抗人DAF单克隆抗体的制备及鉴定

以初步纯化的人红细胞膜ＤＡＦ免疫Ｂａｌｂ／ｃ小鼠,取免疫小鼠脾细胞与ＳＰ２／０骨髓瘤细胞融合,成功地获得３株（ＤＧ３、ＤＧ９和ＤＡ１１）抗人ＤＡＦ单克隆抗体。经间接ＥＬＩＳＡ测定,３株杂交瘤细胞培养上清及腹水的抗体效价分别为１０－３～１０－４及１０－６～１０－７;３株单抗的重链为小鼠ＩｇＧ１亚类,轻链为κ型。结合还原条件下的免疫印迹实验及３株单抗对ＤＡＦ促衰变活性的抑制作用,推测ＤＧ９识别的抗原表位为ＳＣＲ１,而ＤＧ３和ＤＡ１１为ＳＣＲ２至ＳＣＲ４。     

NGF、BDNF及受体trkA、trkB、trkC在正常猴脊髓的表达

采用免疫组织化学方法观察了神经生长因子 (NGF) ,脑源性神经营养因子 (BDNF)以及 NGF家族因子受体 trk A、trk B、trk C的免疫阳性反应在正常猴脊髓的分布。结果表明 :NGF免疫反应阳性的神经元在脊髓灰质各层中均有分布 ,灰、白质内也可见较多的 NGF免疫反应阳性的胶质细胞。 BDNF在脊髓各型神经无有明显的表达 ,特别是前角运动神经元。 trk A、trk B、trk C的免疫阳性反应产物主要分布在灰质的神经元及胶质细胞。本实验结果揭示了在正常猴脊髓中神经营养因子 (NGF、BDNF )及受体 trk A、trk B、trk C的表达状况 ,提示这些神经营养因子及受体在维持猴脊髓神经元的正常生理功能中具有重要作用。     

Neurotrophic factors and clinical recovery in relapsing-remitting multiple sclerosis

Pathogenic autoimmune cells are demonstrated to be able to produce neurotrophic factors during acute phase of multiple sclerosis (MS). In this study, we determined the production of various neurotrophins [brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial cell line-derived neurotrophic factor (GDNF), neurotrophin 3 (NT3) and neurotrophin 4 (NT4)] and some pro-inflammatory cytokines [tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma)] by unstimulated peripheral blood mononuclear cells (PBMC) in 21 relapsing-remitting MS patients during different phases of disease (stable, relapse and post-relapse). During acute phase of disease, we detected a considerable increase of BDNF, TNF-alpha and IFN-gamma production, while significantly higher levels of GDNF, NGF, NT3 and NT4 were found in post-relapse phase. When neurotrophin production was correlated with clinical outcome (complete or partial recovery from new symptoms), we found a significantly higher BDNF production in relapse phase followed by increased GDNF, NGF, NT3 and NT4 levels during post-relapse phase in subjects with complete remission only. During relapse phase, we detected a significant increase of pro-inflammatory cytokines, that was more evident in patients with partial recovery. The neuroprotective potential of immune cells seems to be inversely correlated with disease duration and with the age of patients.     

Localisation of neurotrophin - containing cells in higher vertebrate intestine

Neurotrophins are structurally related proteins that regulate the development, differentiation and maintenance of many neuronal populations. In higher vertebrates (reptiles, birds and mammals) four neurotrophins have been found: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin (NT) 3 and NT4/5. In the gut, experimental data and the occurrence of neurotrophin receptors in intestinal neurons and endocrine cells suggest neurotrophin involvement in intestinal physiology. However, very few data are available regarding the cellular localization and distribution of neurotrophins in the gut. In this study we report the presence of NGF, BDNF and NT3 in neurons and endocrine cells of mouse, duck and lizard intestine. In particular, immunoreactivity to NGF was observed: (a) in both endocrine and nerve cells of mouse and duck intestine, (b) in endocrine cells of lizard gut. Immunoreactivity to BDNF was seen: (a) in nerve cells of mouse intestine, (b) in very few endocrine cells of mouse and duck intestine. Immunoreactivity to NT3 was detected: (a) in nerve cells of the mouse intestine, (b) in endocrine and nerve cells of duck and lizard gut. Our results, together with data previously reported, on the distribution of specific neurotrophin receptors, seem to suggest a possible paracrine/autocrine mechanism of neurotrophin action in both the enteric nervous system and endocrine cells.     

Embryonic geniculate ganglion neurons in culture have neurotrophin-specific electrophysiological properties

Geniculate ganglion neurons provide a major source of innervation to mammalian taste organs, including taste buds in the soft palate and in fungiform papillae on the anterior two thirds of the tongue. In and around the fungiform papillae, before taste buds form, neurotrophin mRNAs are expressed in selective spatial and temporal patterns. We hypothesized that neurotrophins would affect electrophysiological properties in embryonic geniculate neurons. Ganglia were explanted from rats at gestational day 16, when growing neurites have entered the papilla core, and maintained in culture with added brain-derived neurotrophic factor (BDNF), neurotrophin 4 (NT4), nerve growth factor (NGF) or neurotrophin 3 (NT3). Neuron survival with BDNF or NT4 was about 80%, whereas with NGF or NT3 less than 15% of neurons survived over 6 days in culture. Whole cell recordings from neurons in ganglion explants with each neurotrophin condition demonstrated distinctive neurophysiological properties related to specific neurotrophins. Geniculate neurons cultured with either BDNF or NT4 had similar passive-membrane and action potential properties, but these characteristics were significantly different from those of neurons cultured with NGF or NT3. NGF-maintained neurons had features of increased excitability including a higher resting membrane potential and a lower current threshold for the action potential. About 70% of neurons produced repetitive action potentials at threshold. Furthermore, compared with neurons cultured with other neurotrophins, a decreased proportion had an inflection on the falling phase of the action potential. NT3-maintained neurons had action potentials that were of relatively large amplitude and short duration, with steep rising and falling slopes. In addition, about 20% responded with a repetitive train of action potentials at threshold. In contrast, with BDNF or NT4 repetitive action potential trains were not observed. The data demonstrate different neurophysiological properties in developing geniculate ganglion neurons maintained with specific neurotrophins. Therefore, we suggest that neurotrophins might influence acquisition of distinctive neurophysiological properties in embryonic geniculate neurons that are fundamental to the formation of peripheral taste circuits and a functioning taste system.     

Neurotrophin and Neurotrophin Receptors in Vascular Smooth Muscle Cells: Regulation of Expression in Response to Injury

The neurotrophins, a family of related polypeptide growth factors including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-3 and NT-4/5 promote the survival and differentiation of distinctive sets of embryonic neurons. Here we define a new functional role for neurotrophins, as autocrine or local paracrine mediators of vascular smooth muscle cell migration. We have identified neurotrophins, and their cognate receptors, the trk tyrosine kinases, in human and rat vascular smooth muscle cells in vivo. In vitro, cultured human smooth muscle cells express BDNF; NT-3; and trk A, B, and C Similarly, rat smooth muscle cells expressed all three trk receptors as well as all four neurotrophins. Moreover, NGF induces cultured human smooth muscle cell migration at subnanomolar concentrations. In the rat aortic balloon deendothelialization model of vascular injury, the expression of NGF, BDNF, and their receptors trk A and trk B increased dramatically in the area of injury within 3 days and persisted during the formation of the neointima. In human coronary atherosclerotic lesions, BDNF, NT-3, and NT-4/5, and the trk B and trk C receptors could be demonstrated in smooth muscle cells. These findings suggest that neurotrophins play an important role in regulating the response of vascular smooth muscle cells to injury.     

Pacinian corpuscle development involves multiple Trk signaling pathways.

The development of crural Pacinian corpuscles was explored in neonatal mutant mice lacking nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3) or neurotrophin-4 (NT4), or their cognate Trk receptors. Deficits of the corpuscles and their afferents were greatest in NT3, less in BDNF, and least in NT4 null mice. Deletion of NGF or p75(NTR) genes had little or no impact. No Pacinian corpuscles were present in NT3;BDNF and NT3;NT4 double or NT3;BDNF;NT4 triple null mice. Deficits were larger in NT3 than TrkC mutants and were comparable to deficits observed in TrkB or TrkA mutants. Afferents of all corpuscles coexpressed TrkA and TrkB receptors, and some afferents coexpressed all three Trk receptors. Our results suggest that multiple neurotrophins, in particular NT3, regulate the density of crural Pacinian corpuscles, most likely by regulating the survival of sensory neurons. In addition, NT3/TrkB and/or NT3/TrkA signaling plays a greater role than NT3/TrkC signaling in afferents to developing Pacinian corpuscles.     

神经营养因子(NGF、NT-3、BDNF及CNTF)和受体trkA、trkB、trkC在正常大鼠脊髓和胳鼠脊髓移植体的免疫组织化学研究

本研究采用免疫组织化学方法观察了NGF家族（NGF、NT－3、BDNF）和非NGF家族的CNTF以及NGF家族因子受体trkA、trkB、trkC在正常大鼠脊髓腰段的分布和胎鼠脊髓移植体在移植后4周的表达。在正常大鼠脊髓腰段,各神经营养因子及受体反应物主要存在于脊髓灰质,特别是前角的运动神经元。但在脊髓后角的分布稍有不同,BDNF阳性细胞的胞浆染色较深,胞核不染色;而NT－3的胞核染色较胞浆为深,核仁不染色。在胎鼠脊髓移植体,NGF、BDNF、CNTF和NT－3及受体trkA、trkB、trkC均有不同程度的染色。本实验结果揭示了在正常大鼠脊髓神经元内各神经营养因子及受体的表达,提示神经营养因子除具有靶源性来源以外,还有神经元自分泌的产物。而在胎鼠移植体内和其周围组织神经营养因子及其受体的表达,可能是在移植体内的移植细胞自分泌和成鼠脊髓损伤的刺激所引起的,这在移植体的存活和发育中有重要作用。     

Dendritic immune complex trapping cells in the spleen of the snake,

The spleen of the snake , was investigated as to its general histology as well as the presence of immune complex trapping cells both at the light and electron microscopical level. Histological examination revealed that the spleen of this reptile was encapsulated and contained some trabeculae. In the splenic parenchyma two different regions could be distinguished: viz. red and white pulp. The white pulp appeared to be arranged around “central arterioles” and their smaller branches extending towards the periphery of the white pulp. The red pulp was composed of blood sinusoids and cell cords. Electron microscopy revealed at least three types of non-lymphoid cells in the white pulp of the spleen of python: (1) reticulum cells, forming the framework; (2) some macrophages and (3) dendritic cells predominantly located in the periphery of the white pulp. Of these types of non-lymphoid cells, only dendritic cells were able to trap and to retain intravenously injected horseradish peroxidase (HRP)-rabbit-anti-HRP immune complexes on their cell surface as determined by enzymehistochemistry at the light and electron microscopical level. These dendritic cells were frequently found in association with collagen fibres and did not engulf large quantities of carbon particles. These data suggest that dendritic cells in the spleen of the python might be the phylogenetic precursors of the mammalian follicular dendritic cells.     

神经肤Y免疫反应阳性神经纤维在大鼠脾脏内的分布

用ABC免疫组织化学法结合葡萄糖氧化酶-DAB-硫酸镍铵(GDN)显色技术,研究神经肽Y(NPY)免疫反应阳性神经纤维在大鼠脾脏内的分布。结果表明,在脾脏内有较丰富的NPY免疫反应(NPY-IR)阳性神经纤维,它们多呈串珠状,主要伴动脉及其分支走行,也见于脾被膜的结缔组织内,白髓、红髓和边缘区等部位的淋巴组织中,以及脾血窦周围。脾内NPY免疫反应阳性神经纤维与血管和淋巴细胞的关系密切,提示它们对脾淋巴细胞的发育和功能可能有调节作用。NPY可能直接作用于淋巴细胞或通过调节脾的血液循环间接地发挥作用。