Identification of a German Cockroach-Specific Allergen by Human IgE and Rabbit IgG

Light microscopic immunohistochemistry based on the principle of capillary action staining is a widely used method to localize antigens. Capillary action immunostaining, however, has not been tested or applied to detect antigens at the ultrastructural level. The aim of this work was to establish a capillary action staining method for localization of intracellular antigens, using colloidal gold probes.Post-embedding capillary action immunocytochemistry was used to detect maternal IgG in the small intestine of newborn suckling piglets. Pieces of the jejunum of newborn piglets suckled for 12 h were fixed and embedded into LR White resin. Sections on nickel grids were secured on a capillary action glass slide (100 μm wide capillary gap, Bio-Tek Solutions, Santa Barbara CA, distributed by CMS, Houston, TX) by double sided adhesive tape. Immunolabeling was performed by applying reagents over the grids using capillary action and removing reagents by blotting on filter paper. Reagents for capillary action staining were from Biomeda (Foster City, CA). The following steps were performed: 1) wet the surface of the sections with automation buffer twice, 5 min each; 2) block non-specific binding sites with tissue conditioner, 10 min; 3) apply first antibody (affinity-purified rabbit anti-porcine IgG, Sigma Chem. Co., St. Louis, MO), diluted in probe diluent, 1 hour; 4) wash with automation buffer three times, 5 min each; 5) apply gold probe (goat anti-rabbit IgG conjugated to 10 nm colloidal gold, Zymed Laboratories, South San Francisco, CA) diluted in probe diluent, 30 min; 6) wash with automation buffer three times, 5 min each; 7) post-fix with 5% glutaraldehyde in PBS for 10 min; 8) wash with PBS twice, 5 min each; 9) contrast with 1% OSO4 in PBS for 15 min; 10) wash with PBS followed by distilled water for5 min each; 11) stain with 2% uranyl acetate for 10 min; 12) stain with lead citrate for 2 min; 13) wash with distilled water three times, 1 min each. The glass slides were separated, and the grids were air-dried, then removed from the adhesive tape. The following controls were used to ensure the specificity of labeling: i) omission of the first antibody; ii) normal rabbit IgG in lieu of first antibody; iii) rabbit anti-porcine IgG absorbed with porcine IgG.

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Immunocytochemical localization of desmin and vimentin in chick embryonic myocardial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159783 ◽

1990 ◽

Vol 48 (3) ◽

pp. 448-449

Author(s):

Yukiko Sugi

Keyword(s):

Sodium Methoxide ◽

Intermediate Filament Protein ◽

Chick Embryos ◽

Immunocytochemical Localization ◽

Myocardial Cells ◽

Immunofluorescence Study ◽

Immunofluorescent Localization ◽

Rabbit Igg ◽

Semithin Sections ◽

Filament Protein

In cultured skeletal muscle cells of chick, one intermediate filament protein, vimentin, is primarily formed and then synthesis of desmin follows. Coexistence of vimentin and desmin has been immunocytochemically confirmed in chick embryonic skeletal musclecells. Immunofluorescent localization of vimentin and desmin has been described in developing myocardial cells of hamster. However, initial localization of desmin and vimentin in early embryonic heart has not been reported in detail. By quick-freeze deep-etch method a loose network of intermediate filaments was revealed to exist surrounding myofibrils. In this report, immunocytochemical localization of desmin and vimentin is visualized in early stages of chick embryonic my ocardium.Chick embryos, Hamburger-Hamilton (H-H) stage 8 to hatch, and 1 day old postnatal chicks were used in this study. For immunofluorescence study, each embryo was fixed with 4% paraformaldehyde and embedded in Epon 812. De-epoxinized with sodium methoxide, semithin sections were stained with primary antibodies (rabbit anti-desmin antibody and anti-vimentin antibody)and secondary antibody (RITC conjugated goat-anti rabbit IgG).

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In vitro assembly of 2-D crystals from partially purified EA1 protein secreted by Bacillus anthracis strain Delta Sterne-1

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100169110 ◽

1994 ◽

Vol 52 ◽

pp. 276-277

Author(s):

Mary Beth Downs ◽

Wilson Ribot ◽

Joseph W. Farchaus

Keyword(s):

Cell Wall ◽

Molecular Sieves ◽

Cell Envelope ◽

Single Species ◽

Supporting Cell ◽

Surface Layers ◽

Rabbit Igg ◽

In Vitro Assembly ◽

Covalently Linked

Many bacteria possess surface layers (S-layers) that consist of a two-dimensional protein lattice external to the cell envelope. These S-layer arrays are usually composed of a single species of protein or glycoprotein and are not covalently linked to the underlying cell wall. When removed from the cell, S-layer proteins often reassemble into a lattice identical to that found on the cell, even without supporting cell wall fragments. S-layers exist at the interface between the cell and its environment and probably serve as molecular sieves that exclude destructive macromolecules while allowing passage of small nutrients and secreted proteins. Some S-layers are refractory to ingestion by macrophages and, generally, bacteria are more virulent when S-layers are present.When grown in rich medium under aerobic conditions, B. anthracis strain Delta Sterne-1 secretes large amounts of a proteinaceous extractable antigen 1 (EA1) into the growth medium. Immunocytochemistry with rabbit polyclonal anti-EAl antibody made against the secreted protein and gold-conjugated goat anti-rabbit IgG showed that EAI was localized at the cell surface (fig 1), which suggests its role as an S-layer protein.

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An immunocytochemical study of maternal immunoglobulin localization in the suckling pig intestine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016217x ◽

1990 ◽

Vol 48 (3) ◽

pp. 922-923

Author(s):

László G. Kömüves ◽

Donna S. Turner ◽

Kathy S. McKee ◽

Buford L. Nichols ◽

Julian P. Heath

Keyword(s):

Sodium Ethoxide ◽

Intracellular Localization ◽

Protein A ◽

Tween 20 ◽

Intestinal Epithelial ◽

Immunocytochemical Study ◽

Fish Skin ◽

Newborn Piglets ◽

Rabbit Igg ◽

Fish Skin Gelatin

In this study we used colloidal gold probes to detect the intracellular localization of colostral immunoglobulins in intestinal epithelial cells of newborn piglets.Tissues were obtained from non-suckled newborn and suckled piglets aged between 1 hour to 1 month. Samples were fixed in 2.5 % glutaraldehyde, osmicated and embedded into Spurr’s resin. Thin (80 nm) sections were etched with 5% sodium ethoxide for 5 min, washed and treated with 4 % sodium-m-periodate in distilled water for 30 min. The sections were then first incubated with blocking buffer (2 % BSA, 0.25 % fish skin gelatin, 0.5 % Tween 20 in 10 mM Trizma buffer, pH=7.4 containing 500 mM NaCl) for 30 min followed by the immunoreagents diluted in the same buffer, 1 hr each. For the detection of pig immunoglobulins a rabbit anti-pig IgG antiserum was used followed by goat anti-rabbit IgG-Au10 or protein A-Au15 probes.

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