斜带石斑鱼胸腺的显微和超微结构

本文通过解剖及组织切片技术、光学显微镜、透射和扫描电子显微镜技术,对斜带石斑鱼(Epinephelus coioides)胸腺器官组织进行了观察研究。结果表明:斜带石斑鱼胸腺实质主要由胸腺细胞(淋巴细胞)和网状上皮细胞构成。鱼体从Ⅰ龄之后,其胸腺发生明显的变化,与幼鱼有所不同,主要是胸腺可明显区分为三个区域:胸腺外皮质区、内皮质区和髓质区。外皮质区主要由网状上皮细胞、黏液细胞、成纤维细胞和少量淋巴细胞构成,细胞排列疏松;内皮质区主要由密集的淋巴细胞和网状上皮细胞组成,以含有大量的淋巴细胞为特征;髓质区主要由淋巴细胞和较多的网状上皮细胞构成,总体特征是淋巴细胞数量比内皮质区的少,且细胞排列较疏松。外皮质区、内皮质区相当于高等脊椎动物的皮质;髓质区相当于高等脊椎动物的髓质。髓质区之下有结缔组织,在Ⅱ龄以上的成体出现胸腺小体(Hassall's corpuscles)或类似胸腺小体的结构,而且随着年龄的增加,胸腺外皮质区增厚,结缔组织增加,还表现在内皮质区和髓质区组织逐渐萎缩变薄,胸腺的细胞组成类型和淋巴细胞数量上有所变化等等。这些现象在Ⅱ龄鱼开始出现,即胸腺呈现退化迹象,在Ⅲ龄以上鱼体呈现明显的退化和萎缩。胸腺表面扫描电镜结果表明:其上皮细胞表面具有微嵴以及由微嵴组成的指纹状结构,有一些微孔分布。透射和断面扫描电镜的结果进一步表明:胸腺组织内的细胞成分复杂,除了淋巴细胞和网状上皮细胞外,还具有巨噬细胞、肥大细胞、肌样细胞、浆细胞、指状镶嵌细胞和纤维细胞等。     

草鱼胸腺组织学的研究

草鱼胸腺位于鳃腔背上角,紧贴在鳃腔膜之下,突起部分伸入到下颞凹,整个胸腺形态形似菱角。其组织结构可分为外区、中区和内区。中区和内区主要由淋巴细胞和网状上皮细胞构成,在组织结构上分别类似于高等脊椎动物胸腺的皮质和髓质区。胸腺淋巴细胞可分大、中、小三型,小淋巴细胞约占78％,中淋巴细胞约占15％,大淋巴细胞约占4％。在Ⅰ龄草鱼,每毫克胸腺约有3.6×106个胸腺淋巴细胞,Ⅱ龄草鱼约为2×106。Ⅰ至Ⅱ龄草鱼胸腺重量明显地随鱼龄增加,Ⅱ龄以上草鱼胸腺重量变化无规律,成鱼胸腺表现出明显的退化。草鱼胸腺除年龄性退化外,还存在环境因素引起的非年龄性退化。       

小鼠胸腺皮质外位腺苷三磷酸酶的细胞化学定位

对探索细胞之间相互作用的机制,对ＢＡＬＢ／ｃ小鼠胸腺皮质内腺苷三磷酸酶进行了细胞化学定位。结果表明该酶活性主要位于毛细血管基膜,内此细胞皮膜和吞饮小泡;上皮性网状细胞和胸腺细胞的质膜外层,特别是二者的相邻面。巨噬细胞及上皮性网状细胞的溶酶和囊泡也具有此酶活性。本文对外位腺苷三磷酸酶有抑制腺苷三磷酸诱发胸腺细胞凋落死亡的可能性进行了讨论。     

不同月龄近交系五指山小型猪免疫器官的组织形态学

目的对不同月龄近交系五指山小型猪免疫器官组织特点进行观察,为其用于建立人类免疫相关疾病模型提供基础形态学资料。方法2、4和12月龄小型猪免疫器官被分别固定,常规石蜡切片、HE染色,光镜观察。结果4月龄前,胸腺内胸腺细胞和胸腺小体的数量均随年龄的增长逐渐增多;12月龄时,胸腺细胞数量有所减少,排列比较疏松,胸腺小体的数量和体积基本没有变化;2月龄时胸腺小体周围可见许多大小不同的空泡状细胞和细胞碎片。4月龄前,脾白髓动脉周围组织淋巴鞘和脾小结在也随年龄增长而逐渐增多增大,但12月龄时有所减少并维持在一定水平,其变化与大鼠和鸡的基本一致。2月龄淋巴结皮质靠内,髓质靠外,4月龄两者分界不明显,12月龄淋巴小结较大,淋巴细胞排列疏松,髓质内淋巴细胞较少,毛细血管增多。结论从整体结构上观察,近交系五指山小型猪免疫器官的组织学结构与人和其它哺乳动物之间没有明显的差异。     

蛇胸腺胚胎发育的组织学研究

该文应用光镜、电镜和细胞计数技术对胚胎发育期虎斑颈槽蛇胸腺的发育分化进行了研究。在胚胎发育１１期,胸腺原基内出现前淋巴细胞。从胚胎发育１２期至出生前（１６期）,淋巴细胞不断增殖分化,小淋巴细胞逐渐增多,而淋巴母细胞和中淋巴细胞逐渐减少。胸腺皮质和髓质形成于１６期。巨噬细胞以及肌样细胞和胸腺ＡＰＵＤ细胞分别形成于胚胎发育１４期和１５期,随后数量有所增加,分别分布于胸腺皮质和髓质。     

人胎胸腺基质细胞的免疫组织化学观察

用免疫组织化学法观察了六种单克隆抗体在１４例２１～３８周胎儿胸腺基质细胞中的反应。结果表明,三种ＭＨＣ－Ⅱ类抗原的表达有差异。ＨＬＡ－ＤＲ＋和ＨＬＡ－ＤＱ＋细胞多,主要分布于髓质,皮质中较少。ＨＬＡ－ＤＰ＋细胞少,几乎只见于髓质。抗表皮角蛋白抗体阳性的上皮细胞见于部分髓质与少数皮质上皮细胞,被膜及小叶间隔下上皮细胞和胸腺小体。Ｓ－１００＋的交错突细胞主要分布于髓质,皮质中较少。ＭＯ＋２的巨噬细胞见于整个胸腺实质,皮质深层最多。     

胸腺异位的一例报道

我们在取成年猫甲状腺制作组织切片(石蜡切片,HE染色)时,无意中发现在猫的甲状腺组织中除包含有甲状旁腺组织外,还包含有另一组织结构。经镜检为淋巴组织,进一步认定为胸腺。在一个切面上可见到2—3个胸腺小叶,并可分出皮质及髓质,在髓质内可看到1—2个胸腺小体,和正常胸腺结构一样(见图1和2)。     

豚鼠胸腺含P物质、降钙素基因相关肽和神经肽Y神经的定位研究

为研究神经肽调节胸腺生理功能的作用途径,作者采用免疫组织化学ＡＢＣ法结合ＧＤＮ增强技术,以３０μｍ厚恒冷箱切片光镜下观察了豚鼠胸腺内含ＳＰ、ＣＧＲＰ和ＮＰＹ神经纤维的定位与分布。结果发现,ＳＰ和ＣＧＲＰ免疫反应神经纤维在胸腺内分布广泛,呈线状或串珠状,可见于血管周围,小叶间结缔组织和胸腺实质。实质中以皮髓质交界区和髓质区纤维分布较密集,而走行于皮质淋巴组织的神经纤维相对稀疏,胸腺小体附近亦可见含ＣＧＲＰ神经分布。含ＮＰＹ神经纤维主要分布于血管周围、小叶间隔和皮髓质交界区,仅少数分支穿行于皮质胸腺细胞之间。胸腺被膜中有上述３种肽能神经纤维分布。本研究结果表明,胸腺内有丰富的肽能神经分布,这可能是神经肽调节胸腺生理功能的重要方式之一。     

金雕肾脏的组织学观察

利用生物显微技术观察了金雕Aquila chrysaetos肾脏的组织结构.结果表明,金雕肾实质由许多肾小叶构成,每个肾小叶可分为皮质和髓质两部分.肾单位由一个肾小体和一条与其相连的肾小管构成.肾小体由肾小囊和肾小球组成.肾小管分为近曲小管、髓袢、远曲小管和连接小管.集合管分为小叶周集合小管和髓质集合管两部分.具有发达的极周细胞.     

人胎胸腺乙酰胆碱酯酶阳性反应细胞的形态观察

人胎胸腺乙酰胆碱酯酶阳性反应细胞的形态观察王新亭,徐以明,李乐年（徐州医学院组织胚胎学教研室徐州２２１００２）近来研究表明ＡｃｈＥ比Ａｃｈ的分布更为广泛,它不仅存在神经组织中,还存在Ｔ淋巴细胞、肾上腺髓质细胞、颌下腺导管上皮细胞及胸腺淋巴细胞和上皮性...     

Hemopoietic tissue in the adult newt,Notopthalmus viridescens

The presence of developmental stages of lymphocytes and their precurors, as revealed by serial and thin sections of hemopoietic organs of normal adult newts (Notopthalmus viridescens) suggests that lymphopoiesis is limited to the thymus, medulla of the spleen and, to a lesser degree, the intestine. Stromal cells, small lymphocytes, granulocytes, mature erythrocytes and melanocytes were observed either within or near the parenchyma of the thymus. The urodele thymus differs from the thymus of anurans and higher vertebrates in that it lacks a cortex and a medulla, myoid cells and Hassall's corpuscles.     

Identification of thymostimulin secreting cells in calf thymus by immunoperoxidase method

An anti- thymostimulin (TS) serum was tested on calf thymus to study the localization of the hormonal factor. The immunoperoxidase method was applied to tissue fixed in Bouin's fluid and embedded in paraffin, or to tissue fixed in paraformaldehyde and embedded in Epon for semi-thin sections. Immuno-reactivity was shown, with DAB- Fluka , in reticulo-epithelial cells in the medulla, and between the cortex and the medulla, while with DAB-Sigma reactivity was found in the cortex as well. The external cells of Hassall's corpuscles were also reactive. Myoid cells were not reactive. In semi-thin sections a weak reactivity was noted at the periphery of a few lymphocytes. Comparison with the localization of other thymic factors, and the possibility of a functional cycle of the epithelial cells synthesizing one or more factors are discussed.     

Identification of thymostimulin secreting cells in calf thymus by immunoperoxidase method

Summary An anti-thymostimulin (TS) serum was tested on calf thymus to study the localization of the hormonal factor. The immunoperoxidase method was applied to tissue fixed in Bouin's fluid and embedded in paraffin, or to tissue fixed in paraformaldehyde and embedded in Epon for semi-thin sections. Immuno-reactivity was shown, with DAB-Fluka, in reticulo-epithelial cells in the medulla, and between the cortex and the medulla, while with DAB-Sigma reactivity was found in the cortex as well. The external cells of Hassall's corpuscles were also reactive. Myoid cells were not reactive. In semi-thin sections a weak reactivity was noted at the periphery of a few lymphocytes. Comparison with the localization of other thymic factors, and the possibility of a functional cycle of the epithelial cells synthesizing one or more factors are discussed.     

Fine structure of the thymus in the adult cling fish Sicyases sanguineus (Pisces, Gobiesocidae)

The structure of the thumus in adult specimens of a marine teleost, the cling fish Sicyases sanguineus, has been studied by light and transmission electron microscopy. Most cling fishes have an outer thymus located beneath the opercular epithelium. A few of them, however, have a large inner thymus besides a poorly developed outer thymus. In the well-developed outer thymus of cling fish there are three different zones: outer cortex, inner cortex, and medulla. The inner cortex is similar to the cortical region of the thumus in other vertebrates, whereas the outer cortex is a specialized lympho-epithelial zone containing cystic cells (also present in medullary region) and true Hassall's corpuscles. In accordance with the development of the thymic parenchyma, the medullary or basal region may appear either like a true thymic medulla or like a subcapsular region. In the inner thymus, a subcapsular or peripheral "medullary" region and a central area (inverted cortex) show structural features like those of the medullary (basal) and deep cortical regions of the outer thymus, respectively. In addition to the above regions, sometimes there is a lymphomyeloid perithymic infiltration that often extends along connective tissue septa into the perivascular spaces of the gland. Reticuloepithelial, mesenchymal, and unidentified types of stromal cells within the thymus are described. Some erythrocytes, granulocytes, and monocytoid cells are found, but no plasma cells nor erythropoietic foci are evident. The probable significance of these findings is discussed.     

Myoepithelial cells in human thymus: staining, polarization and fluorescence microscopic studies.

Myoid cells in human thymus were studied around the turn of the century, and alterations in patients with cardiovascular disease were reported. It was therefore deemed of interest to reinvestigate these long forgotten cells. The configurational staining, polarization and fluorescence microscopic properties of smooth myofibrils in thymic epithelial cells were identical with those of classical myoepithelial cells, smooth muscle, and A bands of striated muscle. Cross-striated myoid cells could not be found in thymus of children. Myoepithelial cells formed a layer at the surface of thymic lobules; others were scattered throughout the cortex and medulla. In addition, the medulla contained seemingly hypertrophic myoepithelial cells. Hassall's corpuscles consisted of layers of myoepithelial cells. Hammar (1905) regarded epithelial cells with smooth myofibrils in human thymus as equivalents of the cross-striated myoid cells in lower vertebrates. The myoepithelial cells observed in this study are apparently identical with the smooth myoid cells of early anatomists; the hypertrophic myoepithelial cells correspond to the unicellular Hassall's corpuscles. The functions of these cells are not yet clear; the wide variations from case to case in the same age group indicate that the myoepithelial cells are affected by a variety of diseases.     

Macrophages and epithelial cells of the thymus gland. An ultrastructural study in the natterjack, Bufo calamita

In the present study, the ultrastructure of the stromal components, basically epithelial elements and macrophages, of the thymus of adult natterjacks, Bufo calamita has been analyzed. A network of stellate epithelial-reticular cells joined together by desmosomes, constitutes the main component of the thymic parenchyma in both cortex and medulla. In the medulla pale, electron-lucent epithelial cells, sometimes showing surface interdigitations, are striking elements. Moreover, uni- and multicellular epithelial cysts appear in the thymic medulla as well as granulated cells of possible endocrine significance. Remarkably, isolated or grouped gland cells whose morphology and cytoplasmic content resemble that of the skin glands, were occasionally found. Finally, macrophages, multinucleated giant cells and dendritic-like cells, the latter intimately associated to lymphocytes, occur in the thymus of Bufo calamita. The most remarkable morphologic characteristics of all those non-lymphoid cell types, as well as their possible functional significance are comparatively discussed with available information on the amphibian and higher vertebrate thymic cytoarchitecture.     

The dynamics of thymalin localization in human thymus cells in embryogenesis

Immunofluorescence methods were applied to study the localization of the thymalin-containing cells in human thymic epithelium of 6-23-wk-old fetus and 2-3-yr-old infants. The study of the fetal thymus (6 weeks) showed the presence of thymalin in reticuloepithelial framework. These cells were present in both in the cortex (in subcapsular regions) and in the medulla; Thymalin-containing cells presence--in the Hassall's corpuscles (23 weeks). The same results were obtained with the infants thymus (3-yr-old).     

MIGRATION OF SMALL LYMPHOCYTES IN ADULT MICE DEMONSTRATED BY PARABIOSIS

Parabiotic BALB/C mice were used to study the traffic of small lymphocytes in immunological mature but unchallenged mice. By giving ³H-thymidine (³H-TdR) injections to only one member (A) of a pair by preventing the escape of the radioactive isotope to the other member (B), the kinetics of newly-formed cells was followed. Less than 10% labelled small lymphocytes were found in the peripheral lymphoid tissues of both A and B members, while the thymusses and bone marrows of A members showed labelling percentages up to 70% in this period. Hardly any labelled cells gained entrance into the thymus while a detectable number was found in the bone marrows of B members. Results from pairs set up to follow migration of long-lived lymphocytes revealed that labelled cells detected 4–5 weeks after injections were equilibrated between the peripheral tissues and the bone marrows of the partners. Very few labelled cells were seen in the thymic medulla and none were observed in the thymic cortex, germinal centres or medullary cords of lymph nodes from any B member. It was concluded that short-lived small lymphocytes are formed primarily in the thymus and bone marrow and the migration of these cells is limited in adult animals. Furthermore, the vast majority of long-lived small lymphocytes are freely recirculating, and these cells gain entrance to and are normal residents in the bone marrow.