Immunoprobe localization in mammalian embryos

Author(s):  
Patricia G. Calarco ◽  
Margaret C. Siebert

Visualization of preimplantation mammalian embryos by electron microscopy is difficult due to the large size of the ircells, their relative lack of internal structure, and their highly hydrated cytoplasm. For example, the fertilized egg of the mouse is a single cell of approximately 75μ in diameter with little organized cytoskelet on and apaucity ofor ganelles such as endoplasmic reticulum (ER) and Golgi material. Thus, techniques that work well on tissues or cell lines are often not adaptable to embryos at either the LM or EM level.Over several years we have perfected techniques for visualization of mammalian embryos by LM and TEM, SEM and for the pre-embedding localization of antigens. Post-embedding antigenlocalization in thin sections of mouse oocytes and embryos has presented a more difficult challenge and has been explored in LR White, LR Gold, soft EPON (after etching of sections), and Lowicryl K4M. To date, antigen localization has only been achieved in Lowicryl-embedded material, although even with polymerization at-40°C, the small ER vesicles characteristic of embryos are unrecognizable.

1985 ◽  
Vol 75 (1) ◽  
pp. 411-421
Author(s):  
B. Van der Schueren ◽  
D. Gasser ◽  
P. Marynen ◽  
F. Van Leuven ◽  
G. David ◽  
...  

The receptor-mediated endocytosis of gold-labelled alpha 2-macroglobulin complexes with trypsin or methylamine (alpha 2M-T-Au or alpha 2M-MA-Au) was studied by electron microscopy in human skin fibroblasts. The gold label was found in coated structures and very small tubules as well as in tubulovesicular structures and in multivesicular bodies/lysosomes. Thick sections (200 nm), but especially serial thin sections, clearly showed the polymorphic character of the cellular structures involved in endocytosis. Numerous intercommunications were particularly obvious between the tubulovesicular structures, the larger vesicles and the multivesicular bodies (MVB). Continuities between MVBs and endoplasmic reticulum and interconnections between MVBs were also observed. The specificity of the staining reaction was confirmed by indirect labelling of intracellular alpha 2M by polyclonal and by monoclonal antibodies on ultracryosections. These findings are discussed in relation to observations made on epithelial cells with other ligands.


1956 ◽  
Vol 2 (4) ◽  
pp. 163-170 ◽  
Author(s):  
Keith R. Porter

Electron microscopy of thin sections of muscle fibers in myotomes of Amblystoma larvae has revealed the presence of a complex, membrane-limited system of canaliculi and vesicles which form a lace-like reticulum around and among the myofibrils. This seems to correspond to the sarcoplasmic reticulum of the earlier light microscopists and the endoplasmic reticulum of other cell types. The elements constituting the reticulum are disposed in a pattern which bears a constant relation to the bands of the adjacent myofibrils and is therefore repeated in each sarcomere. At the H band the system is transversely continuous but not so at other levels. Longitudinally continuity is interrupted at the Z bands where large vesicles belonging to adjacent sarcomere segments of the system face off on opposite sides of the band. The opposing faces of these vesicles are flat and separated by a space of more or less constant width, in which are located small, finger-shaped vesicles. In view of these and other close structural relationships with the myofibrils it seems appropriate to assign to the system a role in the conduction of the excitatory impulse.


Blood ◽  
1990 ◽  
Vol 76 (8) ◽  
pp. 1503-1513 ◽  
Author(s):  
P Hourdille ◽  
E Heilmann ◽  
R Combrie ◽  
J Winckler ◽  
KJ Clemetson ◽  
...  

Abstract Previous studies have shown a decreased binding of monoclonal antibodies (MoAbs) to glycoprotein (GP) Ib-IX complexes on thrombin- stimulated platelets, but the reason for this is poorly understood. We have used (1) immunofluorescence procedures and flow cytometry, and (2) immunogold staining and electron microscopy to investigate this phenomenon. Washed platelets were incubated with alpha-thrombin, adenosine diphosphate, or ionophore A23187 for increasing lengths of time. For alpha-thrombin, but not the other agonists, flow cytometry confirmed a dose- and time-dependent decrease in the binding of MoAbs specific for GP Ib alpha (AP-1, Bx-1), GP IX (FMC 25), or to the complex itself (SZ 1). Immunoglold staining performed using standard transmission or scanning electron microscopy high-lighted surface areas devoid of bound antibody. However, a quantitatively normal immunofluorescence was restored if paraformaldehyde-fixed, thrombin- stimulated platelets were permeabilized with Triton X-100 (Sigma Chemical Co, St Louis, MO) before MoAb addition, while immunogold staining was now seen to be concentrated within the interior of the platelet. Glutaraldehyde-fixed samples were then embedded in the resin Lowicryl K4M (Taab Laboratories Equipment Ltd, Aldermaston, England) and immunogold staining performed on thin sections using a polyclonal antibody to glycocalicin. An increased presence of GP Ib-IX complexes within surface-connected membrane systems of the thrombin-stimulated platelets was confirmed. Interestingly, GP Ib-IX movement was opposite to the thrombin-induced externalization of internal pools of GP IIb- IIIa complexes and of the alpha-granule membrane GP, GMP-140.


1983 ◽  
Vol 31 (8) ◽  
pp. 987-999 ◽  
Author(s):  
J Roth

A method is described for the electron microscopic detection of lectin-binding sites in different cellular compartments and extracellular structures that uses thin sections from resin-embedded tissues. Various lectins (Ricinus communis lectin I and II, peanut lectin, Lotus tetragonolobus lectin, Ulex europeus lectin I, Lens culinaris lectin, Helix pomatia lectin, and soybean lectin) were bound to particles of colloidal gold and used for direct staining of thin sections or glycoprotein--gold complexes were prepared and applied in an indirect technique (concanavalin A and horseradish peroxidase--gold complex; wheat germ lectin and ovomucoid--gold complex). The details for preparation of such complexes from 14 nm gold particles are reported. The conditions of tissue processing that gave satisfactory staining results and good fine structure preservation were mild aldehyde fixation without osmification and low temperature embedding with the hydrophilic resin Lowicryl K4M. None of the so-called etching procedures was necessary prior to labeling of Lowicryl K4M thin sections. Examples of the use of this approach for detection of glycoconjugates in the rough endoplasmic reticulum, Golgi apparatus, and mucin of intestinal goblet cells as well as plasma membrane and various intracellular structures of absorptive intestinal and renal tubular cells are shown. A comparison is made with preembedding staining results on Concanavalin A-binding site localization in rat liver which shows that problems of penetration common in such a technique are circumvented by the postembedding approach described here. Concanavalin A-binding sites were not only consistently found in nuclear envelope, rough and smooth endoplasmic reticulum, plasma membranes, and collagen fibers, but also in mitochondria, glycogen, ribosomes, and nucleus. These data and those of a previous investigation (Roth J, Cytochem 31:547, 1983) prove the applicability of this cytochemical technique for postembedding localization of glycoconjugates by light and electron microscopy.


1988 ◽  
Vol 36 (7) ◽  
pp. 717-727 ◽  
Author(s):  
S J Hagen ◽  
J S Trier

We used post-embedding immunocytochemical techniques and affinity-purified anti-actin antibody to evaluate localization of actin in epithelial cells of small intestine by fluorescence and electron microscopy. Small intestine was fixed with 2% formaldehyde-0.1% glutaraldehyde and embedded in Lowicryl K4M. One-micron or thin sections were stained with antibody followed by rhodamine- or colloidal gold-labeled goat anti-rabbit IgG, respectively. Label was present overlying microvilli, the apical terminal web, and the cytoplasm directly adjacent to occluding and intermediate junctions. Label was associated with outer mitochondrial membranes of all cells and the supranuclear Golgi region of goblet cells. Lateral cytoplasmic interdigitations between mature cells and subplasmalemmal filaments next to intrusive cells were densely labeled. The cytoplasm adjacent to unplicated domains of lateral membrane was focally labeled. Label was prominent over organized filament bundles within the subplasmalemmal web at the base of mature cells, whereas there was focal labeling of the cytoplasm adjacent to the basal membrane of undifferentiated cells. Basolateral epithelial cell processes were labeled. Label was focally present overlying the cellular ground substance. Our results demonstrate that actin is distributed in a distinctive fashion within intestinal epithelial cells. This distribution suggests that in addition to its function as a structural protein, actin may participate in regulation of epithelial tight junction permeability, in motile processes including migration of cells from the crypt to the villus tip, in accommodation of intrusive intraepithelial cells and in adhesion of cells to one another and to their substratum.


1959 ◽  
Vol 6 (1) ◽  
pp. 77-84 ◽  
Author(s):  
Stuart W. Smith

Sympathetic ganglia of the horned lizard, Phrynosoma cornutum, were fixed in OsO4 and imbedded in methacrylate. Thin sections were cut for electron microscopy. Some adjacent thick sections were cut for light microscopy and were stained in acidified, dilute thionine both before and after digestion by RNase. In the light microscope two types of Nissl bodies are found, both removable by RNase: (1) a deep, diffuse, indistinctly bounded, metachromatic variety, and (2) a superficial, dense, sharply delimited, orthochromatic sort. Electron microscopically, the former ("reticular" Nissl bodies) corresponds to the granulated endoplasmic reticular structure of Nissl material previously described by others, whereas the latter ("areticular" Nissl bodies) comprises compact masses of particles of varying internal density and devoid of elements of endoplasmic reticulum. The constituent particles of the areticular Nissl material are 4 to 8 x the diameter of single ribonucleoprotein granules of the reticular Nissl substance and seem, near zones of junction with the reticular type, to arise by clustering of such granules with subsequent partial dispersion of the substance of the granules into an added, less dense material. It is suggested that the observed orthochromasia of the areticular Nissl substance is due to accumulation of a large amount of protein bound to RNA and, further, that these Nissl bodies may represent storage depots of RNA and protein.


Author(s):  
Alden V. Loud

Williams and Kallman pointed out one of the major artifacts in the electron microscopy of biological thin sections, namely, the failure to form images of membranes which are inclined at large angles within the section. This loss is a significant consideration in the qualitative interpretation of electron micrographs and especially in the quantitative assay of endoplasmic reticulum and mitochondrial cristae membranes. In order to estimate the effective loss of membrane images it would be desirable to use a specimen which provides a considerable length of membrane tilted at a known angle and a simple method of measuring its “visibility”. The spherical nuclear envelopes of rat liver parenchymal cells satisfy these conditions. Figure 1 shows part of a binucleate liver cell in which the nuclear membrane is clearly visible around the larger section but blurred by oblique orientation in the smaller section.


1995 ◽  
Vol 1 (4) ◽  
pp. 151-161
Author(s):  
Kuixiong Gao ◽  
Emma Lou Cardell ◽  
Randal E. Morris ◽  
Bruce F. Giffin ◽  
Robert R. Cardell

Phosphoenolpyruvate carboxykinase (PEPCK) is the rate-limiting gluconeogenic enzyme and in liver occurs in a lobular gradient from periportal to pericentral regions. The subcellular distribution of cytoplasmic PEPCK molecules within hepatocytes and its relationship to organelles have not been determined previously. In this study, we have used immunogold electron microscopy to evaluate the subcellar distribution of the enzyme, in addition to brightfield and epipolarized light microscopy. Cryosections (10 μm) of perfusion-fixed rat liver were collected on silanated slides and immunostained using goat anti-rat PEPCK followed by 5-nm gold-labeled secondary and tertiary antibodies. Additionally, free-floating vibratome sections (25, 50, and 100 μm) of perfusion-immersion-fixed rat liver were immunogold stained using goat anti-rat PEPCK and 5-nm gold-labeled secondary antibody, with and without silver enhancement. The immunogold labeled sections from both procedures were embedded in epoxy resin for the preparation of thin sections for electron microscopy. The results showed that the gold-labeled antibodies penetrated the entire thickness of cryosections, resulting in a high signal for PEPCK, but membranes in general, the smooth endoplasmic reticulum in particular, were not identifiable as electron dense unit membranes. On the other hand, the vibratome sections of well-fixed tissue allowed good visualization of the ultrastructure of cellular organelles, with the smooth endoplasmic reticulum appearing as vesicles and tubules with electron dense unit membranes; however, the penetration of the gold-labeled antibody was limited to cells at the surface of the vibratome sections. In both procedures, PEPCK, as indicated by gold particles, is predominantly in the glycogen areas of the cytosome and not in mitochondria, nuclei, Golgi apparatus, or other cell organelles. Hepatocytes in periportal regions have a compact subcellular distribution of PEPCK shown by gold particles; hepatocytes in pericentral regions have a diffuse subcellular distribution of PEPCK and thus more scattered gold particles. When normal serum replaced the first antibody in the immunogold staining procedures, the background was very low.


1984 ◽  
Vol 32 (11) ◽  
pp. 1167-1176 ◽  
Author(s):  
J Roth ◽  
J M Lucocq ◽  
P M Charest

The development of a cytochemical affinity technique for the demonstration of sialic acid residues by light and electron microscopy is reported. The lectin from the slug Limax flavus, with its narrow specificity for N-acetyl- and N-glycolylneuraminic acid, was applied to tissue sections. Subsequently fetuin-gold complexes were used to visualize the tissue-bound lectin. Different cytochemical controls, including sugar inhibition tests, neuraminidase digestion, the use of fetuin-gold complexes alone, or acid hydrolysis of sections, proved the specificity of the technique. Postembedding staining was performed on frozen, paraffin, or semithin resin sections for light microscopy and on thin sections from low temperature Lowicryl K4M-embedded material for electron microscopy. The distribution of sialic acid residues in rat pancreas, liver, and colonic mucosa was investigated.


1958 ◽  
Vol 4 (1) ◽  
pp. 39-46 ◽  
Author(s):  
J. David Robertson

Schmidt-Lanterman clefts in frog sciatic nerves have been studied in thin sections by electron microscopy utilizing permanganate fixation and araldite embedding. It is shown that they are shearing defects in myelin in which the lamellae are separated widely at the major dense lines. Each lamella consisting of two apposed Schwann cell unit membranes ∼ 75 A across traverses the cleft intact. The unit membranes composing each lamella sometimes are slightly (∼ 50 to 100 A) separated in the clefts. The layers between the lamellae contain membranous structures which may be components of the endoplasmic reticulum. These layers are continuous with the outer layer of Schwann cytoplasm and the thin and inconstant cytoplasmic layer next to the axon (Mauthner's sheath). Each of these layers in perfect clefts constitutes a long helical pathway through the myelin from the axon. One of these is connected with Schwann cytoplasm and the other directly with the outside. A type of cross-sectional shearing defect, not hitherto recognized, is described and shown to be a kind of Schmidt-Lanterman cleft. Incomplete clefts are seen and interpreted as representing stages in a dynamic process whereby the myelin lamellae may be constantly separating and coming together again in life.


Sign in / Sign up

Export Citation Format

Share Document