Biomaterial Database

Rickettsial indirect hemagglutination test: isolation of erythrocyte-sensitizing substance. 1978

J V Osterman, and C S Eisemann

The erythrocyte-sensitizing substances (ESS) of Rickettsia prowazekii and R. conorii were characterized by biological and chemical criteria. ESS could be derived from either soluble or particulate complement-fixing antigens obtained by ether extraction of rickettsiae. The soluble complement-fixing antigen exhibited two peaks of serological activity in potassium tartrate density gradients. The particulate complement-fixing antigen coincided with the more dense peak but was distinguishable by its sedimentation in rate-zonal sucrose gradients. ESS was obtained from each of the complement-fixing-reactive gradient peaks by extraction with hot alkali and was quantified by a modified indirect hemagglutination test. These ESS preparations sedimented similarly in potassium tartrate gradients and were shown to contain protein and carbohydrate, both by colorimetric tests and by incorporation of radioactive precursors. The serological activity of ESS was unaffected by trypsin, but both antigenicity and erythrocyte-binding capacity were reduced after exposure to sodium metaperiodate. Highly purified ESS was rapidly inactivated by potassium tartrate and required stabilization with bovine plasma albumin.

UI	MeSH Term	Description	Entries
D010504	Periodic Acid	A strong oxidizing agent.	Paraperiodic Acid,Periodic Acid (HIO4),Periodic Acids,Acid, Paraperiodic,Acid, Periodic,Acids, Periodic
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
D003168	Complement Fixation Tests	Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.	Complement Absorption Test, Conglutinating,Conglutination Reaction,Conglutinating Complement Absorption Test,Complement Fixation Test,Conglutination Reactions,Fixation Test, Complement,Fixation Tests, Complement,Reaction, Conglutination,Reactions, Conglutination,Test, Complement Fixation,Tests, Complement Fixation
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D006386	Hemagglutination Tests	Sensitive tests to measure certain antigens, antibodies, or viruses, using their ability to agglutinate certain erythrocytes. (From Stedman, 26th ed)	Hemagglutination Test,Test, Hemagglutination,Tests, Hemagglutination
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000942	Antigens, Bacterial	Substances elaborated by bacteria that have antigenic activity.	Bacterial Antigen,Bacterial Antigens,Antigen, Bacterial
D001666	Binding Sites, Antibody	Local surface sites on antibodies which react with antigen determinant sites on antigens (EPITOPES.) They are formed from parts of the variable regions of FAB FRAGMENTS.	Antibody Binding Sites,Paratopes,Antibody Binding Site,Binding Site, Antibody,Paratope
D012281	Rickettsia	A genus of gram-negative, aerobic, rod-shaped bacteria often surrounded by a protein microcapsular layer and slime layer. The natural cycle of its organisms generally involves a vertebrate and an invertebrate host. Species of the genus are the etiological agents of human diseases, such as typhus.