Morphology and ultrastructure of the earthworm Dendrobaena veneta (Lumbricidae) coelomocytes

Microscope techniques, light microscope (LM), transmission electron microscope (TEM), scanning electron microscope (SEM) were employed to describe and classify coelomocytes of the oligochaete Dendrobaena veneta. Three main cell types were distinguished in the coelomic fluid: eleocytes, amoebocytes and granulocytes. Eleocytes are large, oval cells containing characteristic granules called chloragosomes. Amoebocytes are most numerous coelomocytes and have been divided into two types (I and II). Both amoebocytes of the types I and II often form aggregations of a few to about a dozen cells. Granulocytes are oval cells with spherical nuclei and cytoplasm containing polymorphic, electron dense granules. Contrary to the amoebocytes, the granulocytes do not form aggregations. Morphology and ultrastructure of coelomocytes are presented on micrographs: similarities and differences are compared to coelomocytes of related species.     

Sulfated glycosaminoglycans in guinea pig basophils studied by means of cationic colloidal gold

 Bone marrow embedding in the hydrophilic resin, Lowicryl K4M, followed by cationic colloidal gold (CCG, pH 1.0) staining was used to study the sulfated glycosaminoglycans (GAGs) and their sites of sulfation ultrastructurally in various maturational stages of both basophil granulocytes and basophil granules in the guinea pig. CCG at pH 1.0 is specific for sulfated GAG staining. Basophil granulocytes and granules reacted positively to CCG with a variety of staining according to the stage of maturation. The formation of basophil granules takes place throughout the myelocyte stage. Early basophil myelocytes contain a large Golgi apparatus with active granulogenesis, while late myelocytes contain a small and less active Golgi apparatus as judged by CCG staining. All the immature granules and some of the granules with characteristic ultrastructure stained positively. However, some of the mature granules had lost their affinity for CCG upon maturation. Interestingly, strongly positive CCG staining was also observed in the trans to transmost Golgi apparatus. This indicates that sulfation of GAGs occurs in the trans to transmost Golgi apparatus in all maturational stages of basophil granulocytes. Treatment with chondroitinase ABC or heparinase I abolished the majority of CCG staining. Accepted: 17 July 1997     

Comparative study of the ultrastructural characteristics of Torulopsis candida yeasts grown on glucose and hexadecane]

Electron-microscopic examination of the ultrastructure of Torulopsis candida cells grown on glucose and hexadecane revealed a well-developed network of canals in the cell wall of yeasts grown on hexadecane. These canals appeared in the non-adapted cells at the initial hours of the cultivation and completed their formation at the end of the logarithmic phase. The investigation by the freeze-etching showed the exocytosis of "secretory granules" to take place at the periplasma of the cells, and the morphological relationship of the granules to the canals in the cell wall.     

Identification of peripheral blood leucocytes of the dogfish (Scyliorhinus canicula L.) by electron microscopy

Dogfish peripheral blood leucocytes were examined by electron microscopy after the injection of colloidal carbon. The cells were classified as lymphocytes, plasma cells, monocytes, thrombocytes and granulocytes. The granulocytes were further classified into four types according to the structure of their granules. Monocytes, thrombocytes and two types of the granulocytic cells were phagocytic.     

Cytochemical and functional characterization of blood and inflammatory cells from the lizard Ameiva ameiva

The fine structure and differential cell count of blood and coelomic exudate leukocytes were studied with the aim to identify granulocytes from Ameiva ameiva, a lizard distributed in the tropical regions of the Americas. Blood leukocytes were separated with a Percoll cushion and coelomic exudate cells were obtained 24 h after intracoelomic thioglycollate injection. In the blood, erythrocytes, monocytes, thrombocytes, lymphocytes, plasma cells and four types of granulocytes were identified based on their morphology and cytochemistry. Types I and III granulocytes had round intracytoplasmic granules with the same basic morphology; however, type III granulocyte had a bilobued nucleus and higher amounts of heterochromatin suggesting an advance stage of maturation. Type II granulocytes had fusiformic granules and more mitochondria. Type IV granulocytes were classified as the basophil mammalian counterpart based on their morphology and relative number. Macrophages and granulocytes type III were found in the normal coelomic cavity. However, after the thioglycollate injection the number of type III granulocyte increased. Granulocytes found in the coelomic cavity were related to type III blood granulocyte based on the morphology and cytochemical localization of alkaline phosphatase and basic proteins in their intracytoplasmic granules. Differential blood leukocyte counts showed a predominance of type III granulocyte followed by lymphocyte, type I granulocyte, type II granulocyte, monocyte and type IV granulocyte. Taken together, these results indicate that types I and III granulocytes correspond to the mammalian neutrophils/heterophils and type II to the eosinophil granulocytes.     

成年草鱼外周血细胞的超微结构

用透视电镜技术研究了成年草鱼外周血细胞的超微结构，结果表明：在外周血细胞中可区分出红细胞，淋巴细胞，单核细胞，嗜中性白细胞，嗜酸性白细胞和血检细胞；嗜碱性白细胞无论在血涂片上或超薄切片上都没有发现。电镜图像显示，在红细胞中，仅能看到少数线粒体和液泡。淋巴细胞以短的伪足，较多的游离核糖体和滑面内质网为其特征。单核细胞的特征是具有较多的伪足和胞质液泡以及偏位核。在外周血液中发现了嗜中性白细胞生长、发育、功能成熟和衰退的全过程，描述了嗜中性白细胞的幼稚型、成熟型和衰退型细胞的超微结构。在成年草鱼外周血中，还发现了一种新型的颗粒细胞，它的特殊颗粒为大的六角形或棒状致密结晶颗粒，对上述特殊颗粒细胞的属性也进行了讨论。     

Blood and inflammatory cells of the lungfish Lepidosiren paradoxa

A special interest exists concerning lungfish because they may possess characteristics of the common ancestor of land vertebrates. However, little is known about their blood and inflammatory cells; thus the fine structure, cytochemistry and differential cell counts of coelomic exudate and blood leucocytes were studied in Lepidosiren paradoxa. Blood smear analyses revealed erythrocytes, lymphocytes, monocytes, polymorphonuclear agranulocytes, thrombocytes and three different granulocytes. Blood monocytes and lymphocytes had typical vertebrate morphology. Thrombocytes had large vacuoles filled with a myelin rich structure. The polymorphonuclear agranulocyte had a nucleus morphologically similar to the human neutrophil with no apparent granules. Types I and II granulocytes had eosinophilic granules. Type I granulocytes had round or elongated granules heterogeneous in size, while type II had granules with an electron dense core. Type III granulocyte had many basophilic granules. The order of frequency was: type I granulocyte, followed by lymphocyte, type II granulocyte, monocyte, polymorphonuclear agranulocyte and type III granulocyte. Peroxidase localized mainly at the periphery of the granules from type II granulocytes, while no peroxidase expression was detected in type I granulocytes. Alkaline phosphatase was localized in the granules of type II granulocyte and acid phosphatase cytochemistry also labelled a few vacuoles of polymorphonuclear agranulocyte. About 85% of the coelomic inflammatory exudate cell population was type II granulocyte, 10% polymorphonuclear agranulocyte and 5% macrophages as judged by the nucleus and granule morphology. These results indicate that this lungfish utilises type II granulocytes as its main inflammatory granulocytes and that the polymorphonuclear agranulocyte may also be involved in the inflammatory response. The other two granulocytes appear similar to the mammalian eosinophil and basophil. In summary, this lungfish appears to possess the typical inflammatory granulocytes of teleosts, however, further functional studies are necessary to better understand the polymorphonuclear agranulocyte.     

Composition and ultrastructure of elasmobranch granulocytes. I. Dogfishes (Squaliformes)

The blood granulocyte composition of 10 species of dogfish is given, together with ultrastructural observations made on Etmopterus baxteri Leydig organ and blood, and on spleens of Oxynotus bruniensis, Deania calcea, Scymnodon plunketi and blood of Centroscymnus crepidator . Neutrophilic granulocytes, which were common, had spherical granules that developed a dense core, which then lost contents to become lucent. Eosinophilic granulocytes had ovoid or elongated granules with a fibrillar content that became aligned longitudinally, and rarely formed an axial rod. Eosinophils had large spherical granules that were electron-dense but in early stages had a disorganised fibrillar content. These cells correspond to the neutrophils, heterophils and eosinophils, respectively, of other elasmobranchs.
Dogfish granulocytes are compared with those of other elasmobranchs, and their lack of similarity to those of higher vertebrates is noted.     

Ultrastructure of granulocytes of teleost fish (Salmoniformes, Cypriniformes, Perciformes)

Analysis of data on ultrastructure of granulocytes of freshwater and marine bony fish of orders Salmoniformes, Cypriniformes, and Perciformes showed that in all studied species there were revealed two types of granulocytes-neutrophils and eosinophils. The exception was the bluefish Pomatomus saltatrix L. whose pronephros hemopoietic tissue was found to contain one type of the granulocyte line-neutrophils. The identification parameters of granular leukocytes are specific granules filling the cytoplasm. The main form of specific granules in neutrophils of bony fish of various phylogenetic groups is an elongated granule with different distribution of fibrils or a granule that has fibrils-formed crystalloid. Eosinophil granules are mainly of large, electron-dense, homogenous form.     

四种对虾血细胞组成及超微结构

本文应用电镜超薄切片技术,对中国对虾,日本对虾,长毛对虾和草虾的血细胞进行超微结构的研究,根据血细胞形态,超微结构特点,特别是胞质中特征性颗粒的大小和内部结构,区分为四类：１．透明细胞,其胞质不含特征性颗粒,具有较强的吞噬能力;２．小颗粒细胞,其胞质含有高电子密度的小圆形颗粒和条纹状大颗粒,在对虾防御反应中起着关键性作用;３．大颗粒细胞,其胞质中含有高电子密度的均质大颗粒,在宿主防御反应中起着细胞     

An Ultrastructural Study of the Hemocytes of the Pericardial Body in the Ascidian Ciona intestinalis (L.)

Abstract The hemocytes of the pericardial body of Ciona intestinalis were studied by electron microscopy. Our findings showed that stem cells, clear vesicular granulocytes, microgranulocytes, unilocular granulocytes and globular granulocytes are present at the periphery of the smaller-sized pericardial bodies. The stem cells are small round cells with a large nucleus, with or without nucleolus, and homogeneous cytoplasm containing numerous ribosomes. The clear vesicular granulocytes are characterized by an ameboid shape and cytoplasm containing several large electron-lucent vacuoles and small electron-dense granules. The microgranulocytes are variable in shape and contain numerous large electron-dense granules. The unilocular granulocytes show a single large vacuole with an electron-dense or electron-lucent content and a thin layer of peripheral cytoplasm that contains the flattened nucleus. The globular granulocytes are characterized by the presence of large vacuoles containing either fibrogranular material or electron-dense aggregates.     

Hemolymph cells of the bivalve mollusc Mercenaria mercenaria: an electron microscopical study.

The hemolymph cells of Mercenaria mercenaria were studied with the transmission electron microscope. Three morphological types of cells, granulocytes, hyalinocytes, and fibrocytes, are distinguishable and their fine structural characteristics are described. However, as a result of analyzing the fine structural features of the so-called fibrocytes of M. mercenaria, i.e., the inclusion of large aggregates of glycogen granules in their cytoplasm and the occurrence of primary phagosomes enclosing partially degraded exogenous material and digestive lamellae, it is suggested that fibrocytes are actually granulocytes which are at the terminal phase of their physiologic cycle relative to the degradation of phagocytized nonself materials. The cytoplasmic granules of M. mercenaria granulocytes are structurally different from those of Crassostrea virginica in that they are delimited by a unit membrane, rather than by a complex wall, and include a homogenously electron-dense material. Lipidlike droplets are reported from both granulocytes and hyalinocytes of M. mercenaria for the first time.     

The endocrine cells of the pyloric glands of adult ox

As part of a project to identify the endocrine cells ("EC" and "APUD" series) of the gastroenteric apparatus of ruminants, the ultrastructure of the mucosa of the pyloric glands of adult ox was studied morphologically and cytochemically, in parallel with a light microscope histochemical analysis. The results show that: the "EC" cells (producing 5-HT) are recognizable by their secretory granules which are heavily osmiophilic, argentaffin ("Masson") and argyrophilic ("Grimelius"). A further distinction is possible on the basis of their morphological features: the "EC" cells of the gastric type (which belong to the "ECn" group) contain granules fairly homogeneous in shape and size, while the "EC" cells of the intestinal type (or "EC1") show granules which are more pleiomorphic and variable in size. Of particular interest is the presence in some cells of granules typical of the "EC" cells of the intestinal type, in the vicinity of a few others, which appear quite similar to those of the adjoining exocrine cells; the "G" cells (gastrin producing) contain medium sized granules, which are unreactive to "Masson" and poorly argyrophilic. Their morphology is rather diverse; some of them (these are the "typical" cells) have a granular and weakly electron dense content, others (which we consider "atypical") show a homogeneous and heavily osmiophilic core, with an eccentrical empty area. Also present are granules whose appearance is intermediate and empty vesicles; the "D cells" (somatostatin producting) show round, medium sized granules which have a granular, moderately osmiophilic core, tightly encircled by the membrane. These granules are unreactive to "Masson" and to "Grimelius"; the "D1" cells (whose function is yet unclear) contain small, round granules whose core is variously but discretely electron dense and not always homogeneous; they are unreactive to "Masson" and fairly argyrophilic. These granules may be numerous and packed, or scarce; in this latter instance the few granules are intermingled with variously running tufts of parallel filaments, thus resembling the "P" cells, whose function is still undefined. These data show therefore that the types of endocrine cells we have identified in the pyloric glands of adult ox correspond to those described in other mammals; "X" and "F" or "PP" cell appear to be lacking.     

Haemocyte morphology and function in the Akoya Pearl Oyster, Pinctada imbricata

The morphology and cytochemistry of Pinctada imbricata haemocytes were studied in vitro. Three distinct blood cell types were identified; hyalinocytes, granulocytes, and serous cells. Haemocytes were classified based on the presence/absence of granules, and nucleus to cytoplasm ratio. Granulocytes were the most common cell type (62 ± 2.81%), followed by hyalinocytes (36 ± 2.35%), and serous cells (2 ± 0.90%). Granulocytes, and hyalinocytes were found to be immunologically active, with the ability to phagocytose Congo red stained yeast. Of the cells involved in phagocytosis, granulocytes were the most active with 88.8 ± 3.9% of these haemocytes engulfing yeast. Cytochemical stains (phenoloxidase, peroxidase, superoxide, melanin, neutral red) showed that enzymes associated with phagocytic activity were localised in granules within granulocytes. Based on their affinities for Giemsa/May-Grünwald stain, haemocytes were also defined as either acidic, basic or neutral. Hyalinocytes and serous cells were found to be eosinophilic, whilst granulocytes were either basophilic (large granulocytes), eosinophilic (small granulocytes) or a combination of the two (combination granulocytes). Light, differential interference contrast and epi-fluorescence microscopy identified three sub-populations of granulocytes based on size and granularity; small (4.00-5.00 μm in diameter, with small granules (0.05-0.5 μm in diameter), large (5.00-9.00 μm in diameter, with large granules (0.50-2.50 μm in diameter) and combination (5.00-9.00 μm in diameter, with both large and small granules). These observations demonstrate that P. imbricata have a variety of morphologically and functionally specialized haemocytes, many of which maybe associated with immunological functions.     

Differentiation of eosinophilic granulocytes of carp (Cyprinus carpio L.).

Electron-microscopic studies were conducted to observe ultrastructural changes during differentiation of eosinophilic granulocytes in carp (Cyprinus carpio L.). Differentiation at the myelocyte stage was found to relate to specific granules made of dense and light fields. By maturation they assume a mosaic-like texture and in each granule of mature granulocytes, a light, central "internum" and a peripheral dense wrapper can be distinguished. The activity peroxidase and acid phosphatase is located in the internum and of peroxidase in the wrapper of the granules.     

Structural changes produced in Kupffer cells in the rat liver by injection of lipopolysaccharide

Summary The fine structure of Kupffer cells has been studied at various times after an intravenous injection of lipopolysaccharide of Salmonella abortus equii. The most prominent effects were: an increase in the number and dimensions of phagocytic vacuoles (often containing ingested LPS and neutrophilic granulocytes); mitochondrial damage, including disintegration of the matrix and cristae; an increase in the amount of dilated, lucent rough endoplasmic reticulum; presence of fat droplets in the cytoplasm. Five days after injection of lipopolysaccharide, the Kupffer cells had resumed their normal ultrastructure.Several minutes after injection of lipopolysaccharide, platelets adhered to the Kupffer and endothelial cells. Between one and six hours, neutrophilic granulocytes accumulated in the liver sinusoids. The resulting obstruction of the hepatic microcirculation most probably affected cellular ultrastructure by ischaemia. At three days, the number of Kupffer cells was doubled, and increased further at later time intervals.     

Ultrastructure of human blood T-lymphocytes marked with monoclonal antibodies

The ultrastructure of different human blood T-lymphocyte subpopulations was studied by immunoelectron microscopy using "Orthoclone" monoclonal antibodies (OKT-3, OKT-4 and OKT-8) and peroxidase-antiperoxidase (PAP) complex. It was shown that T-lymphocyte subpopulations, distinct in their surface markers and function, possessed some specific features of submicroscopic structure. OKT-4+ cells (helper/inductor) were characterized by small size, high nucleus/cytoplasm ratio and few cytoplasmic organelles. OKT-8+ cells (suppressor/killer) were larger, had low nucleus/cytoplasm ratio and bean-like nucleus, with their cytoplasm containing numerous mitochondria, well-developed Golgi complex and osmiophilic granules.     

The ultrastructure of the interstitial cells of the mesonephros in the teleost fishes of the Black Sea

The ultrastructure of cells that form mesonephros tissues in eight species of bony fish of the Black Sea, Gaidropsarus mediterraneus (L.), Lisa aurata (Risso), Trachurus mediterraneus (Staindachner), Diplodus annularis (L.), Spicara flexuosa (Rafinesque), Gobius niger jozo L., Mullus barbatus ponticus (Essipov) and Scorpaena porcus (L.), was studied. It was shown that the ultrastructure of agranulocytes and rodlet cells in the studied species is similar to that of cells in freshwater bony fish. The differences were observed in the number of ionocyte mitochondria, in the vesicle ultrastructure in the cells with radial vesicle array, and in the ultrastructure of the specific secondary granules of neutrophils and eosinophils.     

Granule formation in rat myeloid cells

Summary Rat bone marrow was fixed in glutaraldehyde, postfixed in osmium tetroxide, and processed for electron microscopy. The myeloid cells were arranged in order of maturation according to their successive compartments.On the basis of their differences in form, substructure, volume, and density five morphologically distinct types of developing granules are to be observed in neutrophil, two in eosinophil, and four in basophil, cells. Primordial granules appear in the interphase of the myeloblast, respectively in the early promyelocytes. The first granules in the neutrophils are pale, of homogeneous structure. These granules grow gradually denser with increasing condensation. In the myelocyte stage polymorphism is more pronounced. In the granulocytes, vacuoles and dense-cored vacuoles indicate the sites of granules. In the eosinophil line, the basophilic bodies decrease in number during differentiation. The eosinophil granules show fewer variations in the course of maturation than the neutrophils. The immature forms of the basophil granules are relatively large, pale, and of globular structure; they undergo condensation and show gradually higher density.Sites of granulogenesis in the rat are first of all the Golgi apparatus and, possibly, the cisternae in the endoplasmic reticulum. On occasion, bodies in a transitional stage between a mitochondrium and a granule can be observed, but whether they may have a bearing on the problem of granulogenesis is an open question.     

Light and Electron Microscopical Characterization of Heterophilic Granulocytes in the Intestinal Wall and Islet Parenchyma of the Hagfish,Myxine glutinosa (Cyclostomata)

Heterophilic granulocytes were studied in the blood, intestinal wall, and islet parenchyma of the Atlantic hagfish (Myxine glutinosa) by light and electron microscopical methods. The granulocytes are pseudoeosinophils and show a PAS-positive cytoplasmic reaction. Ultrastructurally, the cells contain evenly distributed pleomorphic cytoplasmic granules with the granule membrane close to the osmiophilic core. Emigrated blood granulocytes are found extra-vascularly in the submucous connective tissue, and obviously they can pass the basal lamina and migrate into the epithelium of the intestine, bile duct, and islet parenchyma. Though the staining characteristics of hagfish granulocytes are different from those of endocrine cells in the intestinal mucosa and islet parenchyma, intraepithelial granulocytes in some locations may sometimes be difficult to distinguish ultrastructurally from insulin-containing B-cells, since heterophil granules have both a size and a shape close to those of secretion granules in B-cells. However, in contrast to B-cells the granulocytes show the following ultrastructural features: a lobated nucleus with peripherally arranged electron-dense chromatin; cytoplasmic processes and often rod-like granules with no clear space between the granule membrane and core; prominent cytoplasmic vacuoles and microtubules; and sparse mitochondria and endoplasmic reticulum. Furthermore, immigrated granulocytes lack desmosomes and annulate lamellae. Some of the intraepithelial granulocytes in the mucosa show signs of disintegration and cell death. Degenerative cell processes are also described in the islet parenchyma.