Large Cytoplasmic Inclusions Research Articles

Morphogenesis and structure of caprine respiratory syncytial virus.

Cell cultures inoculated with caprine respiratory syncytial virus (RSV) were studied with light, fluorescent, and electron microscopy to determine the morphogenesis and structure of the virus. Small syncytia were seen after 36 hours in culture. After 48 hours in culture, syncytia were large and numerous and pleomorphic cytoplasmic inclusions were seen. These inclusions were more pronounced and numerous later in the infection cycle. Indirect immunofluorescence revealed a diffuse to granular cytoplasmic fluorescence with fluorescing fibrils on the cell surface. With the electron microscope, filamentous (100-160 nm) and spherical (90-160 nm) particles were seen budding off the cell membrane. The number of virus buds diminished with increased size of syncytia. Granular pleomorphic cytoplasmic inclusions were seen near the nucleus, and electron dense masses were seen just beneath the cytoplasmic membrane where large quantities of virus were budding from the cell surface. The first type of inclusion had distinct borders; the second diffuse borders and appeared to contain viral nucleoprotein. Negative staining revealed spherical, pleomorphic, and filamentous forms of the virus; the last form predominated. The virions were covered with club-shaped projections, and the nucleocapsids were seen as fragile strands frequently broken into fragments or as isolated rings. Morphogenesis and structure of the caprine RSV places this virus with the Pneumovirus genus of the Paramyxoviridae family.

Granular cell basal cell carcinoma. A distinct histopathologic entity

In two cases of basal cell carcinoma with prominent granular cell features, light microscopic examination showed a tumor with the general configuration of a nodular basal cell carcinoma. Focally, there were masses of cells with eosinophilic, granular cytoplasm and large cytoplasmic inclusions, strongly suggestive of granular cell myoblastoma. Ultrastructural observations in one case showed numerous lysosome-like organelles that were similar to those described for granular cell myoblastoma, but were identical to those described for the granular cell variant of ameloblastoma, a tumor that frequently resembles basal cell carcinoma. Additional features included tonofilaments and desmosomes, both of which support an epithelial origin for the granular cells in this rare variant of basal cell carcinoma. (<i>Arch Dermatol</i>115:1064-1067, 1979)

Granular Cell Basal Cell Carcinoma

In two cases of basal cell carcinoma with prominent granular cell features, light microscopic examination showed a tumor with the general configuration of a nodular basal cell carcinoma. Focally, there were masses of cells with eosinophilic, granular cytoplasm and large cytoplasmic inclusions, strongly suggestive of granular cell myoblastoma. Ultrastructural observations in one case showed numerous lysosome-like organelles that were similar to those described for granular cell myoblastoma, but were identical to those described for the granular cell variant of ameloblastoma, a tumor that frequently resembles basal cell carcinoma. Additional features included tonofilaments and desmosomes, both of which support an epithelial origin for the granular cells in this rare variant of basal cell carcinoma.

Comparison between pars intercerebralis neurosecretory cells of Glossina and those of other higher Diptera

Three types of the A‐neurosecretory cells (NSCs) were found in the pars intercerebralis (PI) of the adult brain of four species of tsetse flies (Glossina palpalis, G. pallidipes, G. austeni and G. morsitans). The typical formula of their composition is: 8 A1‐, 14 A2‐ and 4 A3‐cells. After permanganate oxidation, the neurosecretory materials (NSMs) of Al‐ and A3‐cells are rich in strong acid groups. The A2‐NSM contains both strong and weak acid groups after this treatment; besides, it retains a weak affinity to acid dyes. In addition to the A‐cells, the PI of Glossina species seems to include a number of NSCs of the type B.The data obtained indicate a great similarity of the NSC composition in the PI of Glossina and other related higher dipterans.In addition to the NSCs, giant neurons and particular cells with large cytoplasmic inclusions were also found in the PI of Glossina. The cells with large cytoplasmic inclusions correspond apparently to vacuolated cells previously observed in the brain of some flies. It is suggested that the considerable complication in reproductive biology which took place in tsetse flies had no effect on the composition of the NSCs in their PI when compared to that in related species with more ordinary cycles of reproduction.

Relay cell classes in the lateral geniculate nucleus of the cat and the effects of visual deprivation

This study presents evidence that the X- and Y-cells described physiologically in the A laminae of the cat's dorsal lateral geniculate nucleus (LGN) are two morphologically distinct cell types recognizable in Golgi preparations. It is shown firstly that the three cell types seen in Golgi preparations of the A laminae (large and medium-sized principal cells and small interneurons-types 1,2 and 3 in the classification of Guillery, '66) may be identified in 1-mum Epon sections of osmicated material. While cell-diameter histograms prepared from serial 1-mum sections show a unimodal distribution of cell sizes, three populations can be distinguished if attention is paid to the presence or absence of large cytoplasmic inclusions (laminar bodies). These three populations consist of large cells lacking laminar bodies (Class I), medium-sized cells possessing laminar bodies (Class II) and small cells lacking them (Class III). That these three classes correspond to the three morphological types has been shown by (i) size comparisons, and (ii) direct demonstration of laminar bodies in the Golgi-impregnated cell bodies of Guillery's type 2 cells. Histograms prepared in this way for samples taken at various positions in the LGN show that the numbers of class II cells decline from the representation of the area centralis to the monocular segment. This decline is compensated by a corresponding rise in the numbers of class I cells. This pattern of distribution is similar to the physiologically observed distribution of X- and Y-cells, indicating that X-cells are likely to be class II cells and Y-cells class I cells. The cortical projections of the various cell types have been examined by the horseradish peroxidase method. Class II cells project to area 17 only. Most class I cells also project to area 17 only, but a few very large class I cells project to area 18. From our results, it appears that very few if any cells in the A laminae have branching axons supplying both 17 and 18. The class III cells do not project to the visual cortex, a finding consistent with their identification as interneurons. Class I and II cells are also found in lamina C and in the MIN. In both these regions there is a predominance of very large class I cells, which project to area 18. Laminae Cl-C3 contain small cells lacking laminar bodies. These cells may project to both areas 17 and 18 with branching axons. They are likely to correspond to Guillery's type 4 cells (small relay cells confined to the C laminae) and to the physiologically described W-cells. Long-term monocular deprivation causes cell shrinkage which is much more severe for class I than for class II cells. There is in addition a decrease in the relative numbers of class I cells. This decrease is found in binocular deprivation also. These observations provide an anatomical basis for the reported loss of Y-cells from deprived laminae of the LGN. It is suggested that the effects of deprivation on Y-cells may be accounted for in terms of competition for synaptic space.

The renal pathology of chediak-higashi disease: Usefulness of the urinary sediment as a confirmatory diagnostic test

The presence of large cytoplasmic inclusions, thought to be abnormal lysosomes, seems to be the cytological hallmark of Chediak-Higashi disease in both humans and animals. This cell anomaly, originally reported in the leukocytes, is also present in various tissue cells, including kidneys. In the patient described, the abnormal inclusions were identified in renal cells of the urinary sediment. Thus, urine could provide a convenient source of diagnostic material in patients with Chediak-Higashi disease. In addition, the ultrastructure of these inclusions is described for the first time in human renal tissue.

The Primary Root Epidermis of Panicum virgatum L. II. Fine Structural Evidence Suggestive of a Plant-Bacterium-Virus Symbiosis

Roots of P. virgatum seedlings have been found to be associated invariably with a symbiotic bacterial species. These bacteria were found both on the surface of, and buried in, the outer walls of the more basal elongating epidermal cells. Often the morphology of the wall-associated bacteria suggested that they were infected with a virulent phage. Other observations included the sudden appearance of virus-like particles in the cytoplasm of these basal elongating epidermal cells. Since the appearance of phage-infected bacteria was found to coincide with the appearance of the cytoplasmic virus-like particles, and since these two events also coincided with the culmination of the ontogeny of large epidermal cytoplasmic inclusions (ECI) in these cells, it has been suggested that these three events may be related.

THE PRIMARY ROOT EPIDERMIS OF PANICUM VIRGATUM L. II. FINE STRUCTURAL EVIDENCE SUGGESTIVE OF A PLANT‐BACTERIUM‐VIRUS SYMBIOSIS

Roots of P. virgatum seedlings have been found to be associated invariably with a symbiotic bacterial species. These bacteria were found both on the surface of, and buried in, the outer walls of the more basal elongating epidermal cells. Often the morphology of the wall‐associated bacteria suggested that they were infected with a virulent phage. Other observations included the sudden appearance of virus‐like particles in the cytoplasm of these basal elongating epidermal cells. Since the appearance of phage‐infected bacteria was found to coincide with the appearance of the cytoplasmic virus‐like particles, and since these two events also coincided with the culmination of the ontogeny of large epidermal cytoplasmic inclusions (ECI) in these cells, it has been suggested that these three events may be related.

Ultrastructure of the larval hemocytes of the silkworm, Bombyx mori L. (Lepidoptera : Bombycidae)

By using ultrastructural characters, the hemocytes of the 5th instar larvae of Bombyx mori were classified into 5 groups: proleucocytes (=prohemocytes), plasmatocytes, granular cells, spherule cells, and oenocytoids. Proleucocytes characteristically contain relatively few cytoplasmic organelles, and may be regarded as embryonic hemocytes. Spindle-shaped plasmatocytes are characterized by an elongated nucleus and by a cytoplasm which is filled with well-developed organelles and numerous small vacuoles. When a nylon thread was inserted into the body cavity, the plasmatocytes reacted to encapsulate the thread. Granular cells are polymorphic in size and shape, but they are characterized by secretory vesicles which are packed with fibers that are 200–250 Å in dia. The inclusions are first produced in cisternae of the endoplasmic reticulum, concentrated in the Golgi complex, and finally released into the hemolymph. India ink particles, when injected in the hemocoele, are mainly incorporated into the granular cells. The spherule cells are characterized by cytoplasmic spherules which contain fine homogeneous granular material. Mature spherule cells release the fine granular materials of the spherules into the hemolymph. These fine granular materials are also concentrated in the Golgi complex, and the fine granules are 150–170 Å in dia. Oenocytoids are large cells characterized by large cytoplasmic inclusions, which are composed of clusters of fibrous proteins arranged in concentric circles. Each fine fiber has a diameter of about 300 Å and is seen to be composed of several subfibrils, each about 50 Å in dia.

Ultrastructure of pulmonary alveolar macrophages in situ in lungs from rats exposed to ozone.

Previous studies of the effects of ozone on pulmonary alveolar macrophages were conducted on cells obtained by bronchoalveolar lavage. The ultrastructure of pulmonary alveolar macrophages were examined in situ in lung tissue of rats exposed to 3 ppm of ozone for 4 hours. Macrophages in the lungs immediately after exposure resembled those in lungs of unexposed animals. These macrophages had active pseudopodia and intact cellular organelles. Three types of membrane-bound cytoplasmic inclusions and one unbound type were present. Twelve hours after exposure to ozone, the number of observed macrophages had doubled. In addition to a normal macrophage population, there were approximately equal numbers of macrophages containing large granular cytoplasmic inclusions that were regarded as Being the result of extensive phagocytic activity. It was concluded that this regimen of ozone exposure did not produce ultrastructurally detectable damage to pulmonary alveolar macrophages in situ within alveoli.

Cytochemical demonstration of ferric iron and fluorescence microscopy observations on ‘Gomori positive’ glia grown in vitro

Large amounts of non-ferritin ferric iron have been revealed cytochemically in granulations of the ‘Gomori positive’ glia grown in vitro. These granulations show a characteristic orange-red autofluorescence present both in living and formalin-fixed cells. The orange-red fluorescence disappears quickly from living cells under strong UV irradiation. Simultaneously, the formation of large globoid cytoplasmic inclusions, showing a strong yellow fluorescence, is observed.

Inclusion bodies in cells infected with radish mosaic virus.

SUMMARY Turnip cells infected with radish mosaic virus contain characteristic large vesiculated cytoplasmic inclusion bodies, visible by light and electron microscopy. They consist of spherical aggregates of virus particles, sometimes in a crystalline array, embedded in a membranous mass. The presence of active dictyosomes and abundant endoplasmic reticulum in the outer zone of young inclusions suggests that these organelles are involved in the formation of inclusion bodies.

Recurring digital fibrous tumour of childhood: An electron microscopic and virological study

A digital fibrous tumour of the type described by Reye was examined with the electron microscope. The large cytoplasmic inclusions that constitute the distinctive histological feature of this lesion were found to comprise compact masses of granules and filaments without a limiting membrane. They closely resembled structures that have been shown to develop in the cytoplasm of cells infected with various species of viruses and that have been interpreted as virus assembly sites. However, no viral particles could be identified in the tumour and attempts to isolate viruses were unsuccessful. Crystals were frequently found in the vicinity of the granular inclusions: their significance was not clear. Bodies that bore a superficial histological resemblance to the inclusions were seen in a tissue culture of the tumour, but contamination of the culture with a yeast prevented studies that might have elucidated their nature.

Anatomical features of Vibrio fetus: Electron microscopic survey.

SUMMARY: Vibrio fetus was examined in shadow-cast, negative-contrast and thin-sectioned preparations; Four morphological types were noted in shadowed specimens: comma, coccoid, S-shaped and filamentous. In negative-contrast preparations organisms were differentiated into two types on the appearance of their cytoplasmic mass. A large spherical cytoplasmic inclusion was frequently evident at the flagellated pole of freshly harvested organisms. Various morphological variants, ‘sports’, e.g. multiflagellate, were easily detected. A non-motile isolate was either devoid of flagella or exhibited only a short stub at the pole. In thin-section preparations anatomical features noted were: a rugose loosely fitting membranous integument; a complex cytoplasmic membrane of honeycomb-like structure; a fibrillar nucleoplasm and fibrillar cytoplasmic ground substance with associated ribosomes; lamellated or cytoplasmic granules bounded by a smooth membrane. At the flagellated pole the cytoplasmic ground substance was generally rarefied and a cone-shaped flagellar basal granule was present. The flagella were enlarged at their proximal terminus. Mesosome-like elaborations of the cytoplasmic membrane were not observed. It was concluded that Vibrio fetus closely resembles members of the genus Spirillum.

The fine structure of an unusual hemocyte in the insect [formula omitted

An unusual hemocyte occurring in the insect Gromphadorhina is described on the basis of electron microscopic as well as light microscopic information. It has been named the crescent cell because of thh shape of its dominant constituent, a single large cytoplasmic inclusion body that contains an amylase-resistant PAS-positive material.

A LIGHT AND ELECTRON MICROSCOPE STUDY OF THE MORPHOLOGICAL CHANGES INDUCED IN RAT LIVER CELLS BY THE AZO DYE 2-ME-DAB.

The cytological changes induced in rat liver cells by the aminoazo dye 2-Me-DAB have been examined by light and electron microscopy. It is observed that this non-carcinogenic compound duplicates most of the morphological alterations produced by other hepatotoxins, some of which, such as the closely related aminoazo dye 3'-Me-DAB, are potent carcinogens. These non-specific effects involve both the granular and agranular forms of the endoplasmic reticulum as well as the glycogen content of hepatic cells. The arrays of cisternal profiles of the granular reticulum in normal hepatic cells become disorganized and the dispersed cisternae often appear fragmented and irregular. Large cytoplasmic inclusions, consisting of loosely organized tubules and vesicles, are also observed which result from a hypertrophy of the agranular reticulum. The glycogen in the cells progressively decreases in amount. The most specific effect of 2-Me-DAB is to induce an increase in the number of mitochondria per cell. Many of these organelles are characterized by the presence of a median double membrane continuous with the inner limiting membrane of the mitochondrial envelope. Evidence is presented in favor of the view that this partition is directly related to the phenomenon of mitochondrial division. It was noted also in the course of the experiment that an increasing number of cells appear which stain quite intensely with methylene blue and appear denser than normal under electron microscopy. The significance of these cells is not known.

SOME OBSERVATIONS ON NUCLEAR STRUCTURE IN CARTILAGE CELLS

SYNOPSISOn comparing the electron‐microscope appearance of, and the sites of tritiated thymidine uptake within, the nuclei of cartilage cells in the growing epiphysis, a corresponding pattern of distribution of electron‐dense material and isotope was found. Similarly, cells capable of tritiated thymidine uptake, and in which metaphase arrests can be produced with colchicine, were found to have electron‐dense nuclei on examination in the electron microscope. When the pattern of tritiated thymidine was changed by the prior administration of growth hormone to the animal, the distribution of electron‐dense nuclei showed the same changes.During the active phase, direct physical connections were observed to exist between the nuclei and surroundings of the cartilage cells. The effect of vitamin C deficiency was to inhibit the formation of endoplasmic reticulum, while leaving the connections between the nucleus and exterior of the cell intact.The main effect of colchicine was to remove the connections between the nucleus and its surroundings, while the nucleolus was frequently enlarged. (The central part of the nucleolus is normally connected directly with a large cytoplasmic inclusion.) Individual chromosomes are rarely seen in cartilage, even after the administration of colchicine, although after this treatment chromosomes were frequently found in marrow cells.