Composition and ultrastructure of elasmobranch granulocytes. II. Rays (Rajiformes)

The blood granulocyte composition of seven species of ray is given together with ultrastructural observations made on the epigonal organ and blood of Pavoraja spinifera and the spleen of a deepwater rajid skate. Under the light microscope three granulocyte types, eosinophils, eosinophilic granulocytes and neutrophilic granulocytes could be distinguished. At the EM level two granulocyte types were apparent, one with elongated granules containing longitudinal fibrils that consolidated to form an axial rod-like inclusion, and the other with large, spherical, uniformly electron-dense granules. Correlation of light and electron microscope observations indicated that the neutrophilic granulocytes with weakly basophilic, elongated granules become weakly eosinophilic, as eosinophilic granulocytes, and these in turn develop to eosinophils with granules containing axial rods. The other granulocyte type forms another population of eosinophils with spherical granules.
The inter-relationship of these granulocytes, the identification of eosinophilic granulocytes, or heterophils, as immature eosinophils, and the co-existence of two morphologically distinct eosinophil forms are discussed.     

Raman microspectroscopic approach to the study of human granulocytes.

A sensitive confocal Raman microspectrometer was employed to record spectra of nuclei and cytoplasmic regions of single living human granulocytes. Conditions were used that ensured cell viability and reproducibility of the spectra. Identical spectra were obtained from the nuclei of neutrophilic, eosinophilic, and basophilic granulocytes, which yield information about DNA and protein secondary structure and DNA-protein ratio. The cytoplasmic Raman spectra of the three cell types are very different. This was found to be mainly due to the abundant presence of peroxidases in the cytoplasmic granules of neutrophilic granulocytes (myeloperoxidase) and eosinophilic granulocytes (eosinophil peroxidase). Strong signal contributions of the active site heme group(s) of these enzymes were found. This paper illustrates the potentials and limitations for Raman spectroscopic analysis of cellular constituents and processes.     

Composition and ultrastructure of elasmobranch granulocytes. III. Sharks (Lamniformes)

The peripheral blood granulocyte composition of five species of shark is given together with ultrastructural observations made on the epigonal organ and blood of Mustelus lenticulatus and spleen of Apristurus sp. Three granulocyte lineages occurred in Mustelus . Ultrastructurally, eosinophilic granulocytes contained granules that were very variable in size and contained parallel fibrillar arrays that were unidirectional in small granules, but which were often orientated in several directions in larger granules. This dense core material sometimes formed angular crystalloids.
Eosinophils had ovoid or irregular granules that were usually uniformly electron-dense, but some had an eccentric ovoid area of greater electron-density. Some eosinophils enter the blood where they are phagocytic, but others, in blood and epigonal organ, showed an unusual but characteristic process of disintegration, leaving a ragged cell full of cellular debris.
The third granulocyte type had features of mast cells and basophils of higher vertebrates and was tentatively identified as belonging to that lineage. The inter-relationships of these cells, and of them with granulocytes of other elasmobranchs, are discussed.     

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.     

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.     

Electron microscopic determination of phenoloxidase (EC 1.14.18.1) in eosinophilic granulocytes of the small intestine of white rats

It is shown that the light microscopic permanent detectable phenoloxidase activity, using dihydroxyphenylalanine as substrate, of the small intestine of white rats is localized in the most cases in eosinophilic granulocytes. The enzyme has been found as well in the cytoplasma as in the granules. The enzyme proof triggered in the granules the so called reverse effect. The results allow to conclude new aspects for the cell mediated immunological defense reaction.     

The enzyme cytochemistry and composition of elasmobranch granulocytes

Peroxidase, alkaline phosphatase, acid phosphatase, β-glucuronidase, α-naphthyl acetate esterase (ANAE), α-naphthyl butyrate esterase, naphthol AS-D chloroacetate esterase, acetyl-L-tyrosine-α-naphthyl esterase (ATNE), tosyl-L-lysine-α-naphthyl esterase (TLNE) and periodic acid-Schiff (PAS) were studied in 17 species of elasmobranchs in which granulocytes had previously been identified at the ultrastructural level.
Eosinophils, eosinophilic and neutrophilic granulocytes contained variable acid phosphatase, esterases and PAS, but they were strongest in neutrophilic granulocytes; particularly ANAE. Esterases were released into surrounding plasma and therefore probably function as ectoenzymes. In eosinophils and some neutrophilic granulocytes there were indications of weak peroxidase, but this could not be conclusively demonstrated. Alkaline phosphatase was diffuse between granules in some eosinophils of Pavoraja , and (β-glucuronidase was diffuse in neutrophilic granulocytes of Etmopterus baxteri , otherwise granulocytes lacked these enzymes. Neutrophilic granulocytes stained moderately to strongly for ATNE and weakly and inconsistently for TLNE in Squalus acanthias and Dalatias licha . with a similar reaction in granular lymphocytoid and thrombocytoid cells of Galeorhinus ausiralis and Raja nasuta . The enzyme composition of these granulocytes is discussed.     

Categorization of hemocytes of three gastropod species Trachea vittata (Muller), Pila globosa (Swainson) and Indoplanorbis exustus (Dehays)

Light microscopic observations were made on the hemocytes of three gastropod species namely Trachea vittata, Indoplanorbis exustus and Pila globosa. It revealed two basic types of hemocytes. They are agranulocytes and granulocytes. Agranulocytes are hyalinocytes which are round, unspread hemocytes and have a large nucleo-cytoplasmic ratio. Granulocytes are spreading hemocytes, forming numerous pseudopodia. For the purpose of differential counting, we present a categorization of the granulocytes into three sub-categories based on cell dimensions, nucleo-cytoplasmic ratio, distribution of granules in the cytoplasm and position of the nucleus. The smaller granulocytes are younger cells, and are termed Granulocytes I (Progranulocytes). The larger ones are fully developed cells that have been differentiated into Granulocyte II (basophilic) and Granulocyte III (eosinophilic).     

Cytochemical identification of the leukocytes of torpedoes (Torpedo marmorata Risso and Torpedo ocellata Rafinisque)

The authors subjected peripheral blood smears of Torpedoes to cytochemical analysis of lipids, protein, neutral and acid polysaccahrides and of some enzymatic activities, i.e. adenosine triphosphatase (ATP-ase), acid and alkaline phosphatase, aliesterase and peroxidase. It was found that neutrophilic granulocytes are intensely PAS and aliesterase positive and weakly ATP-ase positive. Eosinophilic granulocytes show the presence of neutral polysaccharides in the matrix (which is PAS positive) and strong ATP-ase and acid phosphatase activities in the granules. Lymphocytes sometimes contain weakly PAS and aliesterase positive granules. Monocytes show some small PAS positive granules and weak acid phosphatase and aliesterase activities. Thrombocytes contain some peripheral granules which are PAS positive and slightly ATP-ase positive. There are no transitional forms between the various cellular types. The results confirm the classification of leukocytes of Torpedoes into neutrophilic granulocytes, eosinophilic granulocytes, lymphocytes, monocytes and thrombocytes and contribute some informations about the histoenzymatic content of Elasmobranch leukocytes.     

Structural and functional characterisation of the blood cells of the bivalve mollusc,Scrobicularia plana

Light and electron microscopical studies were carried out in order to characterise the blood cells of the bivalve mollusc, Scrobicularia plana. Three types of haemocytes were recognised: eosinophilic granular haemocytes, basophilic granular haemocytes and basophilic agranular haemocytes. The eosinophilic granulocytes were vesicular and contained large granules whereas the basophilic granulocytes were found to contain small granules and glycogen 'lakes'. The basophilic agranular haemocytes were significantly smaller than the granular haemocytes and had a high nucleus to cytoplasm ratio. Functional characterisation of the blood cells identified activity for the lysosomal enzymes: acid phosphatase, beta-glucuronidase, non-specific esterase and arylsulphatase. There was also a weak staining reaction for phenoloxidase and peroxidase activities. Phagocytosis of Gram-positive bacteria was demonstrated by the haemocytes and antibacterial activity was shown by cell-free haemolymph. Assays to determine release of reactive oxygen species from the haemocytes did not detect any reactive oxygen generation.     

Determination of acid α-naphthyl acetate esterase enzyme activity in peripheral blood leukocytes of gazelles (Gazella subgutturosa)

We examined gazelle peripheral blood leucocytes using the α-Naphthyl acetate esterase (ANAE) staining technique (pH 5.8). Our purpose was to determine the percentage of ANAE positive lymphocytes. The proportion of ANAE positive T-lymphocytes was 72%. T-lymphocytes showed an ANAE positive reaction, but eosinophilic granulocytes and monocytes also showed a positive reaction. By contrast, no reaction was detected in B-lymphocytes, neutrophil granulocytes or platelets. The reaction observed in T-lymphocytes was a red-brown coloration, usually 1–2 granules, but enough granules to fill the cytoplasm were detected rarely. As a result of ANAE enzyme staining, we concluded that the staining technique can be used as a cytochemical marker for gazelle T-lymphocytes.     

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.     

Inflammatory cells of teleostean fish: a review focusing on mast cells/eosinophilic granule cells and rodlet cells

In contrast to the roles played by monocytes/macrophages, neutrophils and lymphocytes, the presence and functions of basophils, mast cells/eosinophilic granule cells, eosinophils and rodlet cells in teleosts are areas of controversy. The tissue distribution of mast cells/eosinophilic granule cells in species from a certain genus shows a characteristic pattern, and this pattern is usually also present at the family level. Functionally, the mast cells/eosinophilic granule cells of teleosts show close similarity to the mast cells of mammals. Acute tissue damage is causing mast cell/eosinophilic granule cell degranulation and release of mediators of inflammation, whereas an increase in the number of these cells is often found in chronically inflamed tissues. The mast cells/eosinophilic granule cells of teleosts show marked diversity in their staining properties, with both basophilic and acidophilic components in their granules. In some fish families, e.g. the labrids, the eosinophilic component is dominating, whereas in the pike the granules are strongly basophilic and show the metachromatic staining characteristics found in the granules of mast cells, but being more akin to the granules of the mucosal than to those of the connective tissue type of mast cells of mammals. With respect to rodlet cells, a cell type hitherto clearly demonstrated only in teleosts, a characteristic distribution pattern seems to be established in certain families. In other families rodlet cells are absent in some individuals and present in different tissues in others. However, there is a close relation between the presence of helminths or other noxious agents and the presence of rodlet cells. Massive aggregations of such cells can be seen in affected epithelia of gills or the intestinal tract, and in individuals of species from some fish families they also occur in association with mesothelial and endothelial tissues. The rodlet cell may represent a type of eosinophilic granulocyte that populates the tissues at its immature stage and mature in response to the appropriate stimuli, in a way similar to that of mast cell precursors. Present evidence points to a functional role for the rodlet cells of teleosts in host defence against parasites.     

Lobster (Homarus americanus) hemocytes: Classification,differential counts,and associated agglutinin activity

Four hemocyte types were recognized in the lobster based on size and refractile nature of the granules, the ratios of cytoplasm to nucleus, and Giemsa stain characteristics. Two hyaline types were designated as prohyalocytes (1.8%) and hyalocytes (64.2%), and two granular types were termed eosinophilic granulocytes (12.2%) and chromophobic granulocytes (21.9%). There was no significant difference in the percentages of the different hemocyte types (differential hemocyte counts) between sexes, but hyalocyte and eosinophilic granulocyte percentages varied significantly between populations of lobsters. The data suggested that the difference in agglutinin activity (HA) between lobsters with the same total hemocyte numbers was due to activity associated with fixed hemocytes or quantitative differences in HA activity associated with one or more hemocyte types, rather than an increase in the percentage of any one particular type in circulation.     

Cell types and hydrolytic enzymes of soft shell clam (Mya arenaria) hemocytes

Hemocytes of the soft shell clam, Mya arenaria, based on appearance after Romanowsky-type staining, can be shown to be either granulocytes or agranulocytes comprising 76.5 and 23.5% of the total cell population, respectively. Cytoplasmic granules are basophilic, eosinophilic, or refractile. Cytochemical studies indicate that these cells are markedly heterogeneous with respect to certain hydrolytic lysosomal enzymes and in cytoplasmic glycogen and lipofuscin. The overall activities of these enzymes in clam hemocytes, as estimated by the number of reactive sites, were unrelated to one another. Using consecutive double-staining techniques, individual cells were also found to vary in their enzyme content. These findings emphasize the biochemical individuality of circulating hemocytes and the variations noted probably reflect differences in number and composition of lysosomes.     

Hemocyte classification and differential counts in the dungeness crab, Cancer magister

The primary purposes of this research were to describe and classify the circulating hemocytes of Cancer magister and devise a method for making differential hemocyte counts for crustaceans. C. magister hemocytes were classified using two simple criteria: the presence or absence of cytoplasmic granules and staining characteristics of the granules, if present. Hyalinocytes (HC) were devoid of granules, intermediate granulocytes (IG) contained basophilic granules or a mixture of basophilic and acidophilic granules, and eosinophilic granulocytes (EG) contained large, acidophilic granules. Hemocyte renewal and a hypothetical maturation sequence of C. magister hemocytes are described and discussed. Differential counts revealed that granulocytes were more abundant than hyalinocytes. For 22 crabs, the mean percentage (and range) of each hemocyte class was: IG, 65.97 (57.50–73.80); EG, 17.76 (4.70–26.47); and HC, 16.25 (3.40–34.67). After additional data are collected and analyzed, the routine use of differential counts may prove to be a valuable method for monitoring the status and health of C. magister and perhaps other crustaceans as well.     

Intracellular reactions in single human granulocytes upon phorbol myristate acetate activation using confocal Raman microspectroscopy

We have obtained new evidence for the occurrence of intracellular NADPH-oxidase activity in neutrophilic and eosinophilic granulocytes upon stimulation with phorbol myristate acetate (PMA). PMA activation leads to a partial translocation of cytochrome b(558) from the membranes of the specific granules to the plasma membrane. It was suggested that NADPH-oxidase activity only takes place in the plasma membrane, leading to an extracellular release of oxygen metabolites because cellular self-destruction can be avoided in this way. The effects of PMA activation were indirectly studied in recent experiments employing scavengers of extracellular superoxide anion and hydrogen peroxide, and support for intracellular NADPH-oxidase activity was obtained. In this paper we use Raman microspectroscopy as a direct method to study intracellular molecular reactions that result from cellular triggering by PMA. The molecular specificity of this microscopic method enables us to show that intracellular reduction of both myeloperoxidase (MPO) and cytochrome b(558) occurs in neutrophilic granulocytes. Control measurements with cytochrome b(558)-deficient neutrophilic granulocytes did not show a reduction of intracellular MPO. This is direct support for the occurrence of intracellular NADPH-oxidase activity in organelles that must be in close contact with the azurophilic granules that contain MPO. Furthermore, a comparison was made with chemical reactions occurring in eosinophilic granulocytes after activation with PMA. Moreover, in these cells an intracellular reduction of eosinophil peroxidase was observed.     

Hemocytes of Bulinus truncatus rohlfsi (Mollusca: Gastropoda)

Two basic cell types occur in the hemolymph of Bulinus truncatus rohlfsi: granulocytes and hyalinocytes. Granulocytes are divided into three subtypes: (1) Granulocytes I, which account for 19% of the hemocytes, are small, young amoebocytes with 1–20 filopodia and small numbers of cytoplasmic granules, including some lysosomes; (2) granulocytes II, which account for 78% of the cells, are large, fully developed amoebocytes that possess 1–20 filopodia and many granules, both acidophilic and basophilic, including numerous lysosomes, phagosomes, and mitochondria; and (3) spent granulocytes, which are rare, have few filopodia, large accumulations of glycogen granules and prominent vacuoles in addition to lysosomes in the cytoplasm. These three subtypes of granulocytes probably represent ontogenetic stages within a single cell line. In addition, granulocytes with 40 or more filopodia and little ectoplasm, found in only 1 of 45 snails examined, probably reflect a pathologic condition. Hyalinocytes, which account for 3% of all hemocytes, are similar in size to mature granulocytes, but have few or no cytoplasmic granules and lack filopodia and glycogen granules. Total hemocyte concentration in hemolymph is 328,000 ± 188,000 cells/ml.     

流式细胞术结合组织学方法对柄海鞘血细胞的分类

用流式细胞术研究柄海鞘(Styela clava)血细胞的分类,依据细胞大小及颗粒的复杂程度将血细胞分为5类:即类群R1-R5,各类群分别占血细胞总数的37.15%4±1.01%、15.85%4±2.91%、16.15%4±1.58%、23.65%±3.05%、5.87%±0.31%,上机血样品的密度约106个/ml.组织学方法依据细胞大小、所含颗粒的情况及细胞的染色特征将血细胞分为5类:成血细胞、透明细胞、嗜碱性颗粒细胞、嗜酸性颗粒细胞及吞噬细胞.对两种方法各自所分5类细胞的对应关系进行了讨论.