Fine structure and immunocytochemistry of cells within the endocrine pancreas of the gar (Lepisosteus osseus)

1998 ◽  
Vol 76 (1) ◽  
pp. 6-18 ◽  
Author(s):  
Karen E Groff ◽  
John H Youson
Keyword(s):  
Endocrine Pancreas ◽  
Cell Types ◽  
Structural Features ◽  
Nerve Terminals ◽  
Cell Type ◽  
Similar Morphology ◽  
Islet Tissue ◽  
Ancient Lineage ◽  
D Cell ◽  
D Cells

Routine electron microscopy and immunocytochemistry were used to describe the cell types in the islets of the endocrine pancreas of the gar Lepisosteus osseus, an actinopterygian fish of the order Semionotiformes, which has an ancient lineage. The general fine-structural features of cells composing the islets reflect their synthesis and packaging of protein for liberation at their perivascular surface. Cells are directly apposed to numerous capillaries and they are richly innervated with nerve terminals containing dense-cored vesicles. The islet tissue comprises many B cells, which are easily distinguished by their ubiquitous granules with polymorphous matrix cores and a loose-fitting membrane. These granules are only immunoreactive with an insulin antiserum. Only one type of D cell is found throughout the islets and it contains many granules of varying electron density, the most abundant granule profile being dumbbell-shaped. All granules in this cell type have a tight-fitting limiting membrane and they immunostain with antisomatostatin-14 and -34. Cells at the periphery of the islet contained granules of similar morphology to those in the D cells, but the granules were less numerous. Many granules in the cells were immunoreactive with both antiglucagon and antineuropeptideY, while others immunostained with only one of these antibodies. Since no cells stained exclusively for either glucagon or neuropeptide Y, it was concluded that there are only three cell types in the endocrine pancreas of the gar: B and D cells and a third cell type (A/F) that co-localizes peptides of the glucagon and pancreatic polypeptide family. Although this co-localization is not uncommon in the vertebrate endocrine pancreas, it may have some phylogenetic and (or) ontogenetic significance in this organism.

scholarly journals Modulation of cell-associated plasminogen activator activity by cocultivation of a stem cell and its tumorigenic descendant.

1984 ◽  
Vol 4 (1) ◽  
pp. 160-165 ◽  
Author(s):  
H Y Liu ◽  
P P Yang ◽  
D L Toledo ◽  
W F Mangel
Keyword(s):  
Plasminogen Activator ◽  
Cell Types ◽  
Cell Contact ◽  
Cell Type ◽  
Plasminogen Activator Activity ◽  
Secondary Tumors ◽  
D Cell ◽  
Multipotential Differentiation ◽  
D Cells

The effect of the presence of one cell type on the plasminogen activator activity of another cell type was studied. The cell types, AC and D, were isolated from a rat neuroblastoma (I. Imada and N. Sueoka, Dev. Biol. 66:97-108, 1978). AC cells are stem cells capable of multipotential differentiation in vitro and have little or no cell-associated plasminogen activator activity. D cells are tumorigenic and have high levels of cell-associated plasminogen activator activity. When AC cells were cocultivated with D cells, the plasminogen activator activity of the D cells was dramatically inhibited. The presence of as few as 1,250 AC cells inhibited 70% of the plasminogen activator activity of 20,000 D cells, as determined by a highly quantitative assay. The amount of inhibition by AC cells was proportional to the number of AC cells present. At increasing numbers of AC cells and a constant number of D cells, the Vmax for the activation of plasminogen proportionately decreased and the Km remained constant, implying that AC cells did not alter the structure or concentration of plasminogen. Inhibition was not mediated by a soluble inhibitor secreted by AC cells. Rather, attachment of AC cells adjacent to D cells, i.e., cell-to-cell contact, seemed to be required for inhibition. The substratum-attached material of AC cells, that which remained on the microwell surface after removal of AC cells with EDTA, inhibited D cell plasminogen activator activity. If plasminogen activator activity is involved in metastasis, then regulation of the plasminogen activator activity of one cell type by another cell type may be involved in determining which cells in a tumor can metastasize and where secondary tumors can arise.

Modulation of cell-associated plasminogen activator activity by cocultivation of a stem cell and its tumorigenic descendant

1984 ◽  
Vol 4 (1) ◽  
pp. 160-165
Author(s):  
H Y Liu ◽  
P P Yang ◽  
D L Toledo ◽  
W F Mangel
Keyword(s):  
Plasminogen Activator ◽  
Cell Types ◽  
Cell Contact ◽  
Cell Type ◽  
Plasminogen Activator Activity ◽  
Secondary Tumors ◽  
D Cell ◽  
Multipotential Differentiation ◽  
D Cells

The effect of the presence of one cell type on the plasminogen activator activity of another cell type was studied. The cell types, AC and D, were isolated from a rat neuroblastoma (I. Imada and N. Sueoka, Dev. Biol. 66:97-108, 1978). AC cells are stem cells capable of multipotential differentiation in vitro and have little or no cell-associated plasminogen activator activity. D cells are tumorigenic and have high levels of cell-associated plasminogen activator activity. When AC cells were cocultivated with D cells, the plasminogen activator activity of the D cells was dramatically inhibited. The presence of as few as 1,250 AC cells inhibited 70% of the plasminogen activator activity of 20,000 D cells, as determined by a highly quantitative assay. The amount of inhibition by AC cells was proportional to the number of AC cells present. At increasing numbers of AC cells and a constant number of D cells, the Vmax for the activation of plasminogen proportionately decreased and the Km remained constant, implying that AC cells did not alter the structure or concentration of plasminogen. Inhibition was not mediated by a soluble inhibitor secreted by AC cells. Rather, attachment of AC cells adjacent to D cells, i.e., cell-to-cell contact, seemed to be required for inhibition. The substratum-attached material of AC cells, that which remained on the microwell surface after removal of AC cells with EDTA, inhibited D cell plasminogen activator activity. If plasminogen activator activity is involved in metastasis, then regulation of the plasminogen activator activity of one cell type by another cell type may be involved in determining which cells in a tumor can metastasize and where secondary tumors can arise.

MORPHOLOGY OF ENDOCRINE CELLS IN THE ISLET TISSUE OF THE COD GADUS CALLARIAS

1970 ◽  
Vol 63 (4) ◽  
pp. 679-695 ◽  
Author(s):  
N. W. Thomas
Keyword(s):  
Endocrine Cells ◽  
Secretory Granules ◽  
Cell Types ◽  
Differential Staining ◽  
Cell Type ◽  
Central Mass ◽  
Islet Tissue ◽  
History Of ◽  
Alpha Beta ◽  
Delta Cells

ABSTRACT The principal islet of the cod consists of a central mass of endocrine tissue, surrounded by a capsule of exocrine tissue. Four cell types are recognisable by differential staining and electron microscopy. Three of these correspond in staining reactions and general morphology to alpha, beta and delta cells of other species. Each cell-type contains characteristic secretory granules. The fourth cell-type does not appear to correspond to any other pancreatic endocrine cell although its granules show features common to both alpha and beta cells. It may represent a phase in the life history of one of these cell types or more probably a separate cell-type.

scholarly journals Co-localization of neuroendocrine hormones in the human fetal pancreas

1999 ◽  
pp. 526-533 ◽  
Author(s):  
GM Portela-Gomes ◽  
H Johansson ◽  
L Olding ◽  
L Grimelius
Keyword(s):  
Endocrine Pancreas ◽  
Islet Amyloid Polypeptide ◽  
Gastric Inhibitory Polypeptide ◽  
Cell Types ◽  
Human Fetuses ◽  
Pancreatic Hormones ◽  
Cell Type ◽  
Islet Amyloid ◽  
Fetal Pancreas ◽  
Somatostatin Cells

OBJECTIVE AND DESIGN: Co-localization of the four major pancreatic hormones, and also of islet amyloid polypeptide (IAPP), peptide tyrosine tyrosine (PYY), secretin and neurotensin, has been studied in the endocrine pancreas of human fetuses at 16, 18 and 22 weeks of gestation. METHODS: Double and triple immunofluorescence stainings have been used. RESULTS: All three fetal pancreata contained cells that showed insulin, glucagon, somatostatin, pancreatic polypeptide (PP), IAPP, secretin and PYY immunoreactivity. Neurotensin cells were found in the youngest fetus and gastric inhibitory polypeptide (GIP) in the two older fetuses. Co-localization of two hormones occurred in most of the endocrine cell types in the three fetuses examined, but three hormones occurred in only a few cells and especially in the youngest fetus. Somatostatin cells were the only cell type which was largely monohormonal. Our findings showed that there are two different co-localization patterns: insulin was co-localized mainly with IAPP and glucagon, while secretin and PYY occurred together with glucagon and PP. CONCLUSIONS: These data are the first to describe secretin and neurotensin in the fetal pancreas. Two different co-localization patterns could be distinguished: insulin, IAPP and glucagon, and glucagon, secretin, PP and PYY.

scholarly journals Immunocytochemical Finding of the Amidating Enzymes in Mouse Pancreatic A-, B-, and D-cells

2002 ◽  
Vol 50 (10) ◽  
pp. 1401-1415 ◽  
Author(s):  
Oihana Garmendia ◽  
Maria P. Rodríguez ◽  
Maria A. Burrell ◽  
Ana C. Villaro
Keyword(s):  
Adult Mouse ◽  
Secretory Granules ◽  
Cell Types ◽  
Perinatal Period ◽  
Cytoplasmic Domain ◽  
Cell Type ◽  
Variable Intensity ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1 ◽  
D Cells

α-Amidation is catalyzed by two enzymatic activities, peptidyl-glycine α-hydroxylating mono-oxygenase (PHM) and peptidyl-α-hydroxyglycine α-amidating lyase (PAL), denoted collectively as peptidyl-glycine α-amidating mono-oxygenase (PAM), which also may include transmembrane and cytoplasmic domains. PAM is present in mammalian pancreas, where it appears to be abundant in the perinatal period. Nevertheless, there is no agreement on the cell type(s) that produces PAM or even on its presence in adults. In the present study we found PAM (PHM and cytoplasmic domain) immunoreactivity (IR) in A-, B-, and D-cells of adult mouse pancreas. In contrast to previous reports, PAM IR was found in B-cells of human and rat. Most of the B/D-cells were PAM immunoreactive, although with variable intensity, whereas less than half of A-cells displayed IR. Immunocytochemistry and Western blotting suggested the existence of different PAM molecules. Differences in the cellular distribution of IR for PAM domains were also observed. Whereas PHM-IR was extended throughout the cytoplasm in the three cell types, presumably in the secretory granules, IR for the cytoplasmic domain in A/D-cells was restricted to a juxtanuclear region, perhaps indicating its cleavage in Golgi areas. Although glucagon, insulin, and somatostatin are non-amidated, amidated peptides (glucagon-like peptide 1, adrenomedullin, proadrenomedullin N-terminal 20 peptide) were found in the three cell types.

scholarly journals THE ENDOCRINE CELLS IN THE EPITHELIUM OF THE GASTROINTESTINAL MUCOSA OF THE RAT

1969 ◽  
Vol 40 (3) ◽  
pp. 692-715 ◽  
Author(s):  
W. G. Forssmann ◽  
L. Orci ◽  
R. Pictet ◽  
A. E. Renold ◽  
C. Rouiller
Keyword(s):  
Gastrointestinal Tract ◽  
Morphological Study ◽  
Endocrine Cells ◽  
Cell Types ◽  
Endocrine Function ◽  
Cell Type ◽  
Gastrointestinal Mucosa ◽  
Type Iv ◽  
A Cells ◽  
D Cells

The authors of this study examine the question of whether the so-called enterochromaffin or argentaffin cells of the gastrointestinal tract should be considered as a single cell type. The systematic application of purely morphologic methods has led to the conclusion that the epithelium of the gastrointestinal mucosa comprises endocrine cells of several types. This conclusion is primarily based on the uneven and characteristic distribution of the various cell types along the intestinal tract, an observation precluding the interpretation that the different types correspond to diverse functional stages of the same cell. A specific endocrine function may be attributed to each of the given cell types recognized so far on account of their appearance and their localization in characteristic areas of the gastrointestinal tract. It is acknowledged, however, that a purely morphological study leaves room for doubt. The first cell type is probably responsible for the formation of 5-hydroxytryptamine. Cells of type II are morphologically comparable to the pancreatic A cells and may, therefore, be called intestinal A cells. Cell type III comprises intestinal D cells since their appearance corresponds to that of pancreatic D cells. Cell type IV might well be responsible for catecholamine production, whereas gastrin is in all probability produced in endocrine cell type V. As yet, the thorough morphological study of the gastrointestinal epithelium does not provide information as to additional distinct cellular sites of production of the several other hormones isolated from different parts of the gut.

The Specific Granules of the Pancreatic Islet Tissue of the Frog (Rana temporaria)

1951 ◽  
Vol s3-92 (18) ◽  
pp. 205-220
Author(s):  
E. J. W. BARRINGTON
Keyword(s):  
Pancreatic Islet ◽  
Rana Temporaria ◽  
Secretory Activity ◽  
Cell Types ◽  
Secretory Cycle ◽  
Distinct Cell ◽  
Islet Tissue ◽  
Frog Rana Temporaria ◽  
Specific Granule ◽  
D Cells

An account is given of some characteristics of the pancreatic islet tissue of the frog, based largely on material fixed in Helly's fluid and subsequently postchromed. It is shown that the cells, which superficially differ greatly amongst themselves in appearance, can be interpreted as representing stages in a single secretory cycle, and cannot be readily differentiated into the entirely distinct cell types which have commonly been thought to characterize the islet tissue of other vertebrates. Secretory activity centres round an organelle which is believed to be th e true ‘specific granule’, and which is formed by the condensation of chromophil material within a chromophobe body. The latter develops asudanophil rim which is also a characteristic feature of the specific granule itself, the secretory activity of the latter involving an intense lipoid metabolism and being accompanied by a reduction of chromophilia. These observations cannot at present be readily related to the traditional descriptions of the ‘A’ and ‘B‘ (and more recently ‘D’) cells, although the specific granule in the earlier stages of its activity appears to resemble the ‘A’ granule of other vertebrates in its staining reactions. Certain reactions characteristic of ‘B’ and ‘D’ granules can also be recognized, but it is too early to evaluate these with confidence. The observations are discussed in the light of current views on the cell-inclusions, particular attention being drawn to the similarity which the chromophobe bodies bear to Golgi spheroids (lipochondria), both in their appearance and in their apparent ability to segregate material from the surrounding cytoplasm.

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Dendritic cells of the human epidermis: immuno-electron microscopic studies of la antigen reactivity

1978 ◽  
Vol 36 (2) ◽  
pp. 644-645
Author(s):  
G. Rowden ◽  
M. G. Lewis ◽  
T. M. Phillips
Keyword(s):  
Dendritic Cells ◽  
Langerhans Cells ◽  
Cell Types ◽  
Cell Type ◽  
Electron Microscopic ◽  
La Antigen ◽  
Microscopic Studies ◽  
A Cell ◽  
C3 Receptors ◽  
Antigen Reactivity

Langerhans cells of mammalian stratified squamous epithelial have proven to be an enigma since their discovery in 1868. These dendritic suprabasal cells have been considered as related to melanocytes either as effete cells, or as post divisional products. Although grafting experiments seemed to demonstrate the independence of the cell types, much confusion still exists. The presence in the epidermis of a cell type with morphological features seemingly shared by melanocytes and Langerhans cells has been especially troublesome. This so called "indeterminate", or " -dendritic cell" lacks both Langerhans cells granules and melanosomes, yet it is clearly not a keratinocyte. Suggestions have been made that it is related to either Langerhans cells or melanocyte. Recent studies have unequivocally demonstrated that Langerhans cells are independent cells with immune function. They display Fc and C3 receptors on their surface as well as la (immune region associated) antigens.

scholarly journals Fibroblasts Influence the Efficacy, Resistance, and Future Use of Vaccines and Immunotherapy in Cancer Treatment

Vaccines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 634
Author(s):  
Bailee H. Sliker ◽  
Paul M. Campbell
Keyword(s):  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Cell Types ◽  
Fibroblast Activation Protein ◽  
Cancer Associated Fibroblasts ◽  
Cell Type ◽  
Adaptive Immune ◽  
Adaptive Immune Cells ◽  
New Research ◽  
Tumor Types

Tumors are composed of not only epithelial cells but also many other cell types that contribute to the tumor microenvironment (TME). Within this space, cancer-associated fibroblasts (CAFs) are a prominent cell type, and these cells are connected to an increase in tumor progression as well as alteration of the immune landscape present in and around the tumor. This is accomplished in part by their ability to alter the presence of both innate and adaptive immune cells as well as the release of various chemokines and cytokines, together leading to a more immunosuppressive TME. Furthermore, new research implicates CAFs as players in immunotherapy response in many different tumor types, typically by blunting their efficacy. Fibroblast activation protein (FAP) and transforming growth factor β (TGF-β), two major CAF proteins, are associated with the outcome of different immunotherapies and, additionally, have become new targets themselves for immune-based strategies directed at CAFs. This review will focus on CAFs and how they alter the immune landscape within tumors, how this affects response to current immunotherapy treatments, and how immune-based treatments are currently being harnessed to target the CAF population itself.

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