Localization and Synthesis of Protein Antigenic Sites

1991 ◽

Vol 49 ◽

pp. 270-271

Author(s):

Michael P. Goheen ◽

Marilyn S. Bartlett ◽

James W. Smith

Keyword(s):

Electron Microscopy ◽

Pneumocystis Carinii ◽

Severe Pneumonia ◽

Culture Fluid ◽

Immunogold Labeling ◽

Antigenic Sites ◽

Transmission Electron ◽

Response To Chemotherapy ◽

Acquired Immunodeficiency ◽

Immunodeficiency Syndrome

Studies of the biology of Pneumocystis carinii (PC) are of increasing importance because this extracellular pathogen is a frequent source of severe pneumonia in patients with acquired immunodeficiency syndrome (AIDS) and is a leading cause of mortality in these patients. Immunoelectron microscopic localization of antigenic sites on the surface of PC would improve the understanding of these sites and their role in pathenogenisis of the disease and response to chemotherapy. The purpose of this study was to develop a methodology for visualizing immunoreactive sites on PC with transmission electron microscopy (TEM) using immunogold labeled probes.Trophozoites of PC were added to spinner flask cultures and allowed to grow for 7 days, then aliquots of tissue culture fluid were centrifuged at 12,000 RPM for 30 sec. Pellets of organisims were fixed in either 1% glutaraldehyde, 0.1% glutaraldehyde-4% paraformaldehyde, or 4% paraformaldehyde for 4h. All fixatives were buffered with 0.1M Na cacodylate and the pH adjusted to 7.1. After fixation the pellets were rinsed in 0.1M Na cacodylate (3X), dehydrated with ethanol, and immersed in a 1:1 mixture of 95% ethanol and LR White resin.

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The Application of Protein A-Gold Immunocytochemistry to Studies of Protein Secretion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118989 ◽

1985 ◽

Vol 43 ◽

pp. 426-429

Author(s):

George H. Herbener ◽

Antonio Nanci ◽

Moise Bendayan

Keyword(s):

Tissue Section ◽

Colloidal Gold ◽

Unit Area ◽

Protein A ◽

Extracellular Proteins ◽

Gold Complex ◽

Second Step ◽

Igg Antibodies ◽

Tissue Sections ◽

Antigenic Sites

Protein A-gold immunocytochemistry is a two-step, post-embedding labeling procedure which may be applied to tissue sections to localize intra- and extracellular proteins. The key requisite for immunocytochemistry is the availability of the appropriate antibody to react in an immune response with the antigenic sites on the protein of interest. During the second step, protein A-gold complex is reacted with the antibody. This is a non- specific reaction in that protein A will combine with most IgG antibodies. The ‘label’ visualized in the electron microscope is colloidal gold. Since labeling is restricted to the surface of the tissue section and since colloidal gold is particulate, labeling density, i.e., the number of gold particles per unit area of tissue section, may be quantitated with ease and accuracy.

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Common Antigenic Sites in Human, Bovine and Porcine Fibrinogens

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650157 ◽

1981 ◽

Vol 45 (02) ◽

pp. 169-172 ◽

Cited By ~ 2

Author(s):

Czeslaw S Cierniewski

Keyword(s):

Antigenic Determinants ◽

Antigenic Sites ◽

Specific Antisera ◽

Antigenic Homology ◽

Polypeptide Chains ◽

Fibrinogen Molecule

SummarySpecific antisera to the Aα, Bβ and γ chains of porcine fibrinogen were used to characterize an antigenic homology of human, bovine, and porcine fibrinogens. Antigenic determinants shared by these fibrinogens were mostly formed by the Aα chain. However, in the case of bovine and porcine fibrinogens they were also found in the Bβ and γ polypeptide chains. The results reported here show that the Aα chain determinants exposed on the intact fibrinogen molecule are conserved to a considerably larger extent than those of the Bβ and γ chains.

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