共查询到20条相似文献,搜索用时 62 毫秒
1.
The primary immune response toward internal parasites and other large foreign objects that enter the insect hemocoel is encapsulation. Prior studies indicated that granular cells and plasmatocytes are the two hemocyte types required for capsule formation by the moth Pseudoplusia includens (Lepidoptera: Noctuidae). Capsules formed by P. includens also have a defined architecture with primarily granular cells attaching directly to the target, multiple layers of plasmatocytes adhering to this inner layer of granular cells, and a monolayer of granular cells attaching to the capsule periphery. Dye-exclusion assays indicated that granular cells die shortly after attaching to the capsule periphery, leaving a basal lamina-like layer around the capsule. In examining the mechanisms underlying granular cell death, we found that culture medium preconditioned by plasmatocytes induced apoptosis of granular cells. Characteristics of plasmatocyte-induced apoptosis included condensation of chromatin, cell surface blebbing and fragmentation of nuclear DNA. Plasmatocyte-conditioned medium did not induce apoptosis of other hemocyte types, and medium conditioned by other hemocyte types did not induce apoptosis of granular cells. The adhesive state of granular cells and plasmatocytes also affected levels of apoptosis. Conditioned medium from spread plasmatocytes induced higher levels of granular cell apoptosis than medium conditioned by unspread plasmatocytes. Reciprocally, spread granular cells underwent significantly higher rates of apoptosis than unspread granular cells in medium conditioned by spread plasmatocytes. In situ analysis indicated that granular cells on the periphery of capsules also undergo apoptosis. Collectively, our results suggest that spread plasmatocytes release one or more factors that induce apoptosis of granular cells, and that this response is important in the final phases of capsule formation. 相似文献
2.
Preparations representing populations of (a) basal and spinous cells, (b) granular cells, and (c) stratum corneum cells were obtained by successive treatments of epidermal slices from pig skin with dilute buffered trypsin solutions. Total lipids accounted for about 8% of the cell dry weight in each of the three populations. Phospholipids, which predominated in the basal and spinous cells, accounted for only 21% of the total lipids in the granular cells and less than 0.1% in the stratum corneum. The latter cells contained more cholesterol (23% of total lipid) than either the granular cells (18%) or the basal and spinous cells (8%). The proportion of ceramide was also much higher in the stratum corneum (17%) and granular cells (9%) than in the basal and spinous cells (1%). The relative amounts of glycosphingolipid (glucosylceramide) and cholesteryl sulfate in the total lipids of stratum corneum cells were less than half those in the granular cells and basal and spinous cells. A novel phospholipid was a major component (26% of total) of the phospholipids from granular cells. The compound, which was partially characterized, contained phosphorus, fatty acids, and glycerol (molar ratio 1:3:2) and appeared to be a neutral derivative of phosphatidic acid. 相似文献
3.
Insect hemocytes have historically been identified on the basis of morphology, ultrastructure and hypothesized function. Among insects in the order Lepidoptera, five hemocyte classes are usually recognized: granular cells, plasmatocytes, spherule cells, oenocytoids and prohemocytes. We have generated a panel of monoclonal antibodies (mAbs) against hemocytes of the moth Pseudoplusia includens. In this study, hemocyte identification using 16 different mAbs was compared to identification methods using morphological characters. Three main categories of mAb binding activity were identified: (1) mAbs that specifically labeled only one morphological class of hemocytes, (2) mAbs that labeled granular cells and spherule cells, and (3) mAbs that labeled plasmatocytes and oenocytoids. With one exception, none of the antibodies bound to other tissues in P. includens. However, certain mAbs that specifically labeled granular cells and/or spherule cells in separated hemocyte populations also labeled plasmatocytes co-cultured with granular cells or cultured in granular cell conditioned medium. Overall, our results suggest that granular cells are antigenically related to spherule cells, and that plasmatocytes are antigenically related to oenocytoids. The use of mAbs as hemocyte markers are discussed. 相似文献
4.
用电镜研究初孵扬子鳄的嗅球⒚嗅球的外颗粒层具有明、暗两种细胞⒚僧帽细胞层细胞排列紧密、规则,细胞之间无任何连接结构⒚内颗粒层见有 3~5 个细胞聚集成群,并有个别细胞出现胞质降解现象⒚除内颗粒层部分细胞外,其他各层细胞仍处于较幼稚阶段⒚胶质细胞已发生,外网状层中有薄薄的髓鞘出现⒚突触处于不同的发育阶段,大多为不对称型⒚ 相似文献
5.
Hemocytes collected from larvae of Pseudoplusia includens (Lepidoptera: Noctuidae) were separated by centrifugation on Percoll cushions. The procedure resulted in 95% purity of plasmatocytes and greater than 99% purity of granular and spherule cells. Medium supplemented with chicken serum enhanced cell viability and promoted spreading of plasmatocytes. Cell-free plasma and medium preconditioned by plasmatocytes or granular cells stabilized cells in vitro and also accelerated spreading of plasmatocytes relative to medium supplemented with chicken serum. Oenocytoids were the only morphotype that exhibited endogenous phenoloxidase activity, while granular cells and plasmatocytes were the only cells that endocytosed fluorescent beads in vitro. Granular cells and plasmatocytes ingested fluorescently labelled beads, both in mixed populations of hemocytes and after separation. Plasmatocytes were the only morphotype that encapsulated large foreign targets in vitro following separation. Separated granular cells attached and spread on the surface of foreign targets but never formed a multilayered capsule. 相似文献
6.
O A Kryshtal' Iu V Osipchuk T N Shelest 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(6):643-645
To perform rapid optical detection of possible pH changes accompanying electrical activity hippocampal slices were stained with pH indicator--phenol red (0.2 mM). Electrical response of granular and pyramidal cells was evoked by stimulation of perforant path, Schaffer collateral and commissural afferents in the stratum radiatum. Biphasic pH changes occurred both in pyramidal and granular cells: rapid acid changes, with the maximum reached in several msec, were followed by alkaline changes lasting up to one sec. pH changes disappeared with the blocking of synaptic transmission by Mg2+ (10 mM) and were absent in antidromic stimulation of granular cells. pH changes are believed to be related to the processes accompanying synaptic transmission. 相似文献
7.
Dr. Peter Bjerregaard 《Cell and tissue research》1975,161(4):485-495
The intraepithelial lymphoid cells of chicken small intestine were studied by light microscopy using 1 mu Epon sections, and by electron microscopy. Three cell types were found: small lymphocytes, large lymphoid cells, and granular cells. These cells correspond to the theliolymphocytes and globule leucocytes of previous authors. The numbers of all cell types increased with age. Correlation was found between the number of small lymphocytes and large lymphoid cells, but not between granular cells and either of the other two. A hypothesis is proposed, assigning these cells with a function in mucosal immunity. 相似文献
8.
S A Vinores 《Histochemistry》1991,96(3):265-269
The origin of the nests of granular cells comprising choristomas of the infundibular process and the stalk of the pituitary gland is controversial. Using electron microscopic immunocytochemistry, the astrocytic marker, glial fibrillary acid protein (GFAP), has been demonstrated diffusely in the cytoplasm of some of the granular cells, but not within the granules or cellular organelles of some of the granular cells. Cytoplasmic filaments were not detected in these granular cells, but cells with abundant filaments extended processes between the granular cells. These filament-rich cells stained much more intensely for GFAP than the positively staining granular cells. The expression of GFAP by the granular cells and the filament-containing cells between them in the pituitary implies an astrocytic origin for both cell types, but the absence of filaments in the granular cells suggests that the GFAP is in an unpolymerized (soluble) form. The granular cell is likely to represent a transitional cell type of astrocytic origin in which the glial filaments have undergone partial or complete degradation. 相似文献
9.
Mallik MK Das DK Francis IM al-Abdulghani R Pathan SK Sheikh ZA Luthra UK 《Acta cytologica》2001,45(2):263-266
BACKGROUND: Granular cell tumors are neoplasms of uncertain histogenesis, although a neural origin is favored. Most reports on the cytologic features of granular cell tumors have been on lesions from the breast or respiratory tract. However, there are only a few reports on fine needle aspiration (FNA) cytologic diagnosis of cutaneous or soft tissue granular cell tumors. CASE: A 7-year-old girl presented with a skin lesion on her right forearm of one year's duration. The FNA smears showed sheets and clusters of oval to polygonal cells with an abundant amount of granular cytoplasm. Many single, scattered cells with similar morphology were seen in the background. Immunostaining for S-100 protein showed granular cytoplasmic positivity. The tumor was diagnosed as a benign granular cell tumor. The histopathology report on the excised lesion confirmed the FNA diagnosis. CONCLUSION: The cytopathologic features of granular cell tumors presenting as skin lesions are distinctive enough to allow a correct diagnosis on FNA cytology. 相似文献
10.
M Denechaud J M Israel F Belloc J D Vincent 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1987,304(16):427-431
The different antehypophysical cell types which synthetize and release somatotroph (GH), corticothroph (ACTH), gonadotroph (LH-FSH) and lactotroph (PRL) hormones were analysed. The experiments were performed on hypophyses from five groups of animals: adult males, 14 days-old female, adult females, gestating adult females and lactating adult females. The cells were analysed by immunofluorescence using flow cytometry. For each of the hormones studied, there was a characteristic spectral distribution of cells. The evolution of cell size and granular content with respect to sex and physiological state of each group was studied by the analysis of diffused light. Small, slightly granular cells represented 50% of the cell population in males and 14 day-old females but only 8% in gestating or lactating females. The study of the cell cycle showed the presence of dividing cells in the population of large, granular cells from gestating and from lactating females. No features of cell division were observed in the population of small, slightly granular cells. This study indicates the potential value of multiparametric analysis in the separation of pure sub-populations of antehypophysial cells. 相似文献
11.
Nardi JB 《Development genes and evolution》2004,214(1):19-28
Cell-mediated responses of the moth immune system involve the interaction of two main classes of hemocytes—granular cells and plasmatocytes. During embryogenesis, granular cells arise much earlier than plasmatocytes, and the presence of granular cells is closely coupled with the formation of basal laminae that line the hemocoel occupied by hemocytes. Although epithelial cells contribute the large extracellular matrix protein lacunin to embryonic matrices before granular cells begin contributing this protein to basal laminae, the spatial pattern of lacunin expression in early embryos parallels the later distribution of granular cells over surfaces of basal laminae. Plasmatocytes arise late in embryogenesis, after the cessation of the major morphogenetic movements and the establishment of intact basal laminae. Granular cells are intimately involved with remodeling of basal laminae, and disruptions in the structure of basal laminae can trigger an autoimmune response of granular cells and plasmatocytes. By arising after basal laminae have been molded and remodeled by granular cells, plasmatocytes presumably do not encounter the cues that trigger their aggregation and an autoimmune response.Edited by P. Simpson 相似文献
12.
S. A. Vinores 《Histochemistry and cell biology》1991,96(3):265-269
Summary The origin of the nests of granular cells comprising choristomas of the infundibular process and the stalk of the pituitary gland is controversial. Using electron microscopic immunocytochemistry, the astrocytic marker, glial fibrillary acid protein (GFAP), has been demonstrated diffusely in the cytoplasm of some of the granular cells, but not within the granules or cellular organelles of some of the granular cells. Cytoplasmic filaments were not detected in these granular cells, but cells with abundant filaments extended processes between the granular cells. These filament-rich cells stained much more intensely for GFAP than the positively staining granular cells. The expression of GFAP by the granular cells and the filament-containing cells between them in the pituitary implies an astrocytic origin for both cell types, but the absence of filaments in the granular cells suggests that the GFAP is in an unpolymerized (soluble) form. The granular cell is likely to represent a transitional cell type of astrocytic origin in which the glial filaments have undergone partial or complete degradation. 相似文献
13.
Alexandre Lobo-da-Cunha 《Acta zoologica》2001,82(3):201-212
The digestive system of the sea hare, Aplysia depilans , includes a pair of ribbon-shaped salivary glands. A central duct and a large blood vessel run close to each other along the length of these glands and both are surrounded by a layer of muscle cells. Three cell types form the glandular epithelium: granular cells, vacuolated cells and mucocytes. The granular cells possess cilia and spherical secretion granules, located primarily in the apical region. The granules of immature cells have a low electron density and are mainly formed by neutral polysaccharides with small amounts of proteins. The granules of mature cells are larger, have a high electron density and are mainly formed by proteins with lower amounts of neutral polysaccharides. Transition stages between immature and mature granular cells are observed. The vacuolated cells are large and frequently pyramidal in shape, but after the application of histochemical techniques almost all vacuoles remain uncoloured. The numerous vacuoles contain flocculent material in a clear background and the mitochondria possess large crystalline structures in the matrix. A pyramidal shape is also typical of the mucocytes, which are filled with vesicles containing granular masses surrounded by a network of secretion material. These large cells are strongly stained by Alcian blue, revealing the presence of acidic mucopolysaccharides. This is the first ultrastructural study of the salivary glands in opisthobranch gastropods. 相似文献
14.
中华绒螯蟹血细胞的显微、亚显微形态结构及其分类 总被引:8,自引:0,他引:8
通过相差显微镜和电镜观察,根据中华绒螯蟹血细胞胞质内有无颗粒以及颗粒大小、染色反应、折光性和形成方式的特点,血细胞分为胞质内无颗粒的无颗粒细胞、胞质内只有具折光性和呈淡红色反应大颗粒的大颗粒细胞、胞质内只有无折光性和呈淡蓝色染色反应小颗粒的小颗粒细胞以及胞质内同时具有大颗粒和小颗粒二种颗粒特性的大小颗粒中间型细胞.小颗粒的形成方式是高尔基体成熟面小泡脱离后直接成为小颗粒,而大颗粒的形成方式是高尔基体成熟面小泡脱离后,数个小泡逐渐聚集成蜂窝状大颗粒,进一步发育成熟为均质大颗粒.实验结果表明:三种有颗粒的细胞是互相独立的,可能分别由无颗粒细胞分化而成.
相似文献
15.
采用普通染色及免疫组化SABC染色法研究皖西白鹅小脑皮质的发育和多巴胺受体1(DRD1)阳性细胞在其发育中的表达.结果表明,小脑皮质在胚龄13 d(E13)由外向内分为外颗粒层(EGL)、浦肯野细胞层(PCL)和内颗粒层(IGL),E19由外向内分为EGL、分子层(ML)、PCL和IGL.随发育天数的增加,EGL的厚度和细胞层次呈先升后降的变化趋势,细胞密度逐渐下降;ML厚度逐渐增大,在E24到E28时增值最大;浦肯野细胞(PC)在E13、E19、E24和E28时随胚龄增大逐渐增大,在E28后趋于稳定,细胞密度随着发育天数的增加逐渐下降,在小脑皮质发育中还发现有一部分PC呈多层排列,且细胞层次逐渐变少;IGL厚度呈先升后降的变化趋势,细胞密度呈上升趋势.外颗粒层和内颗粒层在E13、E19、E24和E28时有DRD1阳性细胞表达,分子层在E24、E28、日龄7 d(P7)和15d(P15)有阳性细胞表达,PC在所检测的6个时段均有阳性表达.研究表明,小脑皮质的发育主要与细胞增殖、迁移和凋亡有关,外颗粒层的逐渐消失是以细胞迁移和凋亡为主,多层PC逐渐退化成单层是与细胞凋亡和正常突触联系的建立有关;DRD1在皖西白鹅小脑皮质发育中对外颗粒层细胞和PC起着重要作用. 相似文献
16.
OBJECTIVE: To describe the cytomorphologic features of benign granular cell tumor (GCT) on fine needle aspiration (FNA) biopsy and discuss the differential diagnosis. STUDY DESIGN: We reviewed three fine needle aspirates of surgically confirmed benign GCT. Immunocytochemical staining for S-100 was performed on the aspirate smear in one case. RESULTS: Two GCT were thigh lesions, where lipoma and fibromatosis were the leading clinical diagnosis, and the third was a breast mass clinically suspected to be a fibroadenoma. All FNA specimens were highly cellular and composed of fairly uniform cells with eccentric, round-to-slightly oval nuclei and abundant, finely granular cytoplasm. The cells were fragile, with stripped nuclei in a background of finely granular material. Occasional cells with nuclear pleomorphism and small-but-conspicuous nucleoli were identified. There was no evidence of necrosis or mitotic activity. Rare intranuclear cytoplasmic inclusions were identified in two cases. The granular cells were immunoreactive for S-100 in the case studied. CONCLUSION: Benign GCT has a distinctive cytomorphologic appearance that permits its diagnosis on FNA. High cellularity, occasional cells with nuclear pleomorphism and prominent nucleoli are features that can be present in benign GCT. Mitotic figures and necrosis should be identified before a diagnosis of malignancy is rendered. 相似文献
17.
The tunic of Cystodytes dellechiajei (Poly- citoridae), a colony-forming species of the Ascidiacea that contains biologically active alkaloids, was investigated
using light microscopy, laser-scanning microscopy and nuclear magnetic resonance techniques. The colonies contain numerous
individual zooids, which are embedded in a common tunic. Each zooid is protected by a firm capsule of overlapping calcareous
spicules. The colonies lack blood vessels in the tunic, but six morphologically different types of tunic cells were found:
pigment cells, bladder cells, vacuolated filopodial cells, granular filopodial cells, morula cells and granular cells. Rod-like
bacteria were found in the tunic matrix. Bladder cells and pigment cells could be identified as storage units for acid and
pyridoacridine alkaloids, making the tunic inedible and repelling predators. Filopodial cells have long filopodia, which probably
are connected to each other. They may be involved in transportation processes within the tunic tissue. The functions of the
morula cells and the granular cells are unknown as yet. With its several specialised cells, the tunic of C. dellechiajei represents a dynamic living tissue containing biologically active compounds.
Accepted: 20 September 2000 相似文献
18.
Five types of haemocytes: prohaemocytes, plasmatocytes, granular haemocytes, spherule cells and phagocytes, have been distinguished on the basis of ultrastructural studies. Prohaemocytes are ovoid cells with a simple structural organization. Plasmatocytes are larger; their cytoplasm contains well-developed rough endoplasmic reticulum, numerous mitochondria and free ribosomes. Granular haemocytes are the most numerous of the blood cells, characterized by the presence of electron-dense granules. The cytoplasm of spherule cells contains many spherules made up of filamentous material of medium electron density. Rough endoplasmic reticulum, free ribosomes and mitochondria are also found in the cytoplasm. Phagocytes are the largest haemocytes. Their cytoplasm contains an abundance of lysosomes and myelin structures. In addition to haemocytes, cells intermediate between plasmatocytes and granular haemocytes have been observed, which indicates that the granular haemocytes are derived from plasmatocytes. 相似文献
19.
Changes in the frog urinary bladder granular cell ultrastructure were analysed in parallel with those in element composition of these cells after induction of water transport across the urinary bladder wall. Two ultrastructural (ultrathin section and freeze-fracture) methods were used in addition to two methods of object preparation for electron microprobe analysis--freeze-drying and freeze-substitution. It has been shown that arginin-vasotocin stimulation of osmotic water flow across the urinary bladder wall causes certain morphological changes in the granular cells: decrease in electron density of the cytoplasm, depolymerization of the apical submembrane layer of actin microfilaments, increase in the number of sites of specific granules and apical membrane fusion, emergency of intramembrane particle aggregates in the apical membrane P-face. The quantitative electron microprobe analysis made it possible to reveal a statistically significant increase in sodium and calcium concentration and fall in that of potassium and chlorine in granular cells after water transport stimulation. A concentration gradient of sodium and potassium ions was seen to appear along the apical-basal axis in the cytoplasm of granular cells. Possible association between the obvious morphological transformations in granular cells and changes in their elemental composition has been discussed, in addition to some regulatory significance of calcium concentration increase in granular cells after arginin-vasotocin-induced osmotic water transport. 相似文献
20.
Abstract The blood cells of a solitary ascidian, Halocynthia roretzi, were examined by electron microscopy (EM) with reference to their appearance by light microscopy (LM). In addition, their movement and stainability by vital dyes was observed by phase-contrast microscopy, and their stainability by Giemsa was also examined. Nine cell types were recognized: vacuolated cells, hyaline amoebocytes, small amoebocytes, granular amoebocytes, macrogranular cells, globular cells, lymphocyte-like cells, large basophilic cells and large granular cells. Vacuolated cells were found to possess various numbers of vacuoles containing strongly electron-dense materials and could be divided into at least three subgroups. Granular amoebocytes contained microfilaments and many granules of uniform size. Hyaline amoebocytes and small amoebocytes seemed to be specialized as phagocytes. Macrogranular cells and globular cells were not well characterized. In the blood of adult individuals, hemoblasts were rarely found, although lymphocyte-like cells were present. Each of two large cells, large basophilic cells and large granular cells, possessed novel granules or vacuoles, whose functions remain to be elucidated. The possible functions and relationships of these cells among various ascidian species are discussed. 相似文献