Biomaterial Database

Spontaneous aggregation of washed human erythrocytes in isotonic media of reduced ionic strength. Conclusions about the spatial arrangement of the N-terminal part of the glycophorins. 1982

D Lerche

Aggregation measurements of washed human erythrocytes (RBC) were made in an NaCl-PBS solution under laminar shear conditions. An artificial aggregation was caused by decreased pH and reduced ionic strength and characterized by collision efficiency, i. e. the probability of permanent aggregate formation. It was found that aggregation increases with reduced ionic strength and decreased pH value of the medium. Aggregation can be inhibited by addition of human serum albumin and neuraminidase treatment (removal of sialic acids). As calculations show, the results cannot be explained by the force balance between electrostatic repulsion and attraction due to dispersion forces. It was assumed that this type of aggregation involves reversible changes of the surface structure of RBC. Possible conclusions for the arrangement of the glycophorins of the glycocalyx (surface coat) are discussed.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009994	Osmolar Concentration	The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.	Ionic Strength,Osmolality,Osmolarity,Concentration, Osmolar,Concentrations, Osmolar,Ionic Strengths,Osmolalities,Osmolar Concentrations,Osmolarities,Strength, Ionic,Strengths, Ionic
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D004903	Erythrocyte Aggregation	The formation of clumps of RED BLOOD CELLS under low or non-flow conditions, resulting from the attraction forces between the red blood cells. The cells adhere to each other in rouleaux aggregates. Slight mechanical force, such as occurs in the circulation, is enough to disperse these aggregates. Stronger or weaker than normal aggregation may result from a variety of effects in the ERYTHROCYTE MEMBRANE or in BLOOD PLASMA. The degree of aggregation is affected by ERYTHROCYTE DEFORMABILITY, erythrocyte membrane sialylation, masking of negative surface charge by plasma proteins, etc. BLOOD VISCOSITY and the ERYTHROCYTE SEDIMENTATION RATE are affected by the amount of erythrocyte aggregation and are parameters used to measure the aggregation.	Erythrocyte Aggregation, Intravascular,Agglutination, Intravascular,Intravascular Agglutination,Intravascular Erythrocyte Aggregation,Rouleaux Formation, Erythrocyte,Agglutinations, Intravascular,Aggregation, Erythrocyte,Aggregation, Intravascular Erythrocyte,Aggregations, Erythrocyte,Aggregations, Intravascular Erythrocyte,Erythrocyte Aggregations,Erythrocyte Aggregations, Intravascular,Erythrocyte Rouleaux Formation,Erythrocyte Rouleaux Formations,Formation, Erythrocyte Rouleaux,Formations, Erythrocyte Rouleaux,Intravascular Agglutinations,Intravascular Erythrocyte Aggregations,Rouleaux Formations, Erythrocyte
D006021	Glycophorins	The major sialoglycoprotein of human erythrocyte membranes. It consists of at least two sialoglycopeptides and is composed of 60% carbohydrate including sialic acid and 40% protein. It is involved in a number of different biological activities including the binding of MN blood groups, influenza viruses, kidney bean phytohemagglutinin, and wheat germ agglutinin.	Erythrocyte Sialoglycoproteins,Glycoconnectin,Glycoconnectins,Glycophorin,Glycophorin D,MN Sialoglycoprotein,Red Blood Cell Membrane Sialoglycoprotein,Glycophorin A,Glycophorin A(M),Glycophorin B,Glycophorin C,Glycophorin E,Glycophorin HA,Ss Erythrocyte Membrane Sialoglycoproteins,Ss Sialoglycoprotein,beta-Sialoglycoprotein,Sialoglycoprotein, MN,Sialoglycoprotein, Ss,Sialoglycoproteins, Erythrocyte,beta Sialoglycoprotein
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D012794	Sialic Acids	A group of naturally occurring N-and O-acyl derivatives of the deoxyamino sugar neuraminic acid. They are ubiquitously distributed in many tissues.	N-Acetylneuraminic Acids,Acids, N-Acetylneuraminic,Acids, Sialic,N Acetylneuraminic Acids