scholarly journals The identification of specific Rhesus-polypeptide-blood-group-ABH-active-glycoprotein complexes in the human red-cell membrane

1987 ◽  
Vol 244 (3) ◽  
pp. 735-741 ◽  
Author(s):  
S Moore ◽  
C Green

1. RhD,c and E immune complexes isolated from 3H- and 125I-surface-radiolabelled and unlabelled intact human red cells were analysed by SDS/polyacrylamide-gel electrophoresis. 2. Apparent Mr values of 31,900 for RhD polypeptide and 33,100 for Rhc,E polypeptide were obtained under both reducing and non-reducing conditions. Glycosylation of RhD,c and E polypeptides was not detected. 3. RhD,c and E immune complexes also contain a glycoprotein component. RhD glycoprotein (apparent Mr 45,000-100,000) is distinct from Rhc,E glycoprotein(s) (apparent Mr 35,000-65,000). Rh (Rhesus) glycoprotein carbohydrate moieties are susceptible to endo-beta-galactosidase digestion and carry blood-group-ABH determinants. This suggests the presence of polylactosaminoglycan-type structures. 4. Rh glycoproteins are not present in Rh immune complexes as a result of non-specific adsorption of membrane glycoproteins during the membrane-solubilization phase of immune-complex isolation because RhD immune complexes isolated from a 1:1 (v/v) mixture of Acde/cde and OcDE/cDE red cells do not contain blood-group-A-active glycoprotein. 5. Blood-group-A immune complexes isolated from group-A red cells of the appropriate Rh phenotypes contain the 31,900- and 33,100-apparent-Mr Rh polypeptides. 6. It was concluded from the above evidence that non-covalent Rh-glycoprotein-Rh-polypeptide complexes exist in the native red-cell membrane. 7. The 31,900- and 33,100-apparent-Mr Rh polypeptides are absent from blood-group-A immune complexes isolated from regulator type Rhnull cells (donor A.L.), but are replaced by a 33,800-apparent-Mr Rhnull-specific polypeptide (Rhnull polypeptide). It is suggested that Rhnull polypeptide is an aberrant product of the Rh gene complex.

1974 ◽  
Vol 64 (6) ◽  
pp. 706-729 ◽  
Author(s):  
W. R. Redwood ◽  
E. Rall ◽  
W. Perl

The permeability coefficients of dog red cell membrane to tritiated water and to a series of[14C]amides have been deduced from bulk diffusion measurements through a "tissue" composed of packed red cells. Red cells were packed by centrifugation inside polyethylene tubing. The red cell column was pulsed at one end with radiolabeled solute and diffusion was allowed to proceed for several hours. The distribution of radioactivity along the red cell column was measured by sequential slicing and counting, and the diffusion coefficient was determined by a simple plotting technique, assuming a one-dimensional diffusional model. In order to derive the red cell membrane permeability coefficient from the bulk diffusion coefficient, the red cells were assumed to be packed in a regular manner approximating closely spaced parallelopipeds. The local steady-state diffusional flux was idealized as a one-dimensional intracellular pathway in parallel with a one-dimensional extracellular pathway with solute exchange occurring within the series pathway and between the pathways. The diffusion coefficients in the intracellular and extracellular pathways were estimated from bulk diffusion measurements through concentrated hemoglobin solutions and plasma, respectively; while the volume of the extracellular pathway was determined using radiolabeled sucrose. The membrane permeability coefficients were in satisfactory agreement with the data of Sha'afi, R. I., C. M. Gary-Bobo, and A. K. Solomon (1971. J. Gen. Physiol. 58:238) obtained by a rapid-reaction technique. The method is simple and particularly well suited for rapidly permeating solutes.


Blood ◽  
1989 ◽  
Vol 74 (5) ◽  
pp. 1836-1843 ◽  
Author(s):  
G Pasvol ◽  
JA Chasis ◽  
N Mohandas ◽  
DJ Anstee ◽  
MJ Tanner ◽  
...  

Abstract The effect of well-characterized monoclonal antibodies to red cell surface molecules on the invasion of human red cells by the malarial parasites Plasmodium falciparum and Plasmodium knowlesi was examined. Antibodies to glycophorin A (GP alpha) inhibit invasion for both parasite species, and this is highly correlated with the degree to which they decrease red cell membrane deformability as measured by ektacytometry. This effect on rigidity and invasion was also seen with monovalent Fab fragments. The closer the antibody binding site was to the membrane bilayer, the greater was its effect on inducing membrane rigidity and decreasing parasite invasion. Antibodies to the Wright determinant in particular were the most inhibitory. This differential effect of the various antibodies was not correlated with their binding affinities or the number of sites bound per cell. Antibodies to surface molecules other than GP alpha were without effect. A novel mechanism is described whereby monoclonal antibodies and their Fab fragments directed at determinants on the external surface of red cells might act to inhibit invasion by malarial parasites by altering membrane material properties.


Glycobiology ◽  
2010 ◽  
Vol 21 (2) ◽  
pp. 162-174 ◽  
Author(s):  
L. Svensson ◽  
L. Bindila ◽  
J. Angstrom ◽  
B. E. Samuelsson ◽  
M. E. Breimer ◽  
...  

Blood ◽  
1987 ◽  
Vol 69 (2) ◽  
pp. 401-407
Author(s):  
RS Schwartz ◽  
JA Olson ◽  
C Raventos-Suarez ◽  
M Yee ◽  
RH Heath ◽  
...  

The intraerythrocytic development of the malaria parasite is accompanied by distinct morphological and biochemical changes in the host cell membrane, yet little is known about development-related alterations in the transbilayer organization of membrane phospholipids in parasitized cells. This question was examined in human red cells infected with Plasmodium falciparum. Normal red cells were infected with strain FCR3 or with clonal derivatives that either produce (K+) or do not produce (K-) knobby protuberances on the infected red cells. Parasitized cells were harvested at various stages of parasite development, and the bilayer orientation of red cell membrane phospholipids was determined chemically using 2,4,6-trinitrobenzene sulphonic acid (TNBS) or enzymatically using bee venom phospholipase A2 (PLA2) and sphingomyelinase C (SMC). We found that parasite development was accompanied by distinct alterations in the red cell membrane transbilayer distribution of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS). Increases in the exoplasmic membrane leaflet exposure of PE and PS were larger in the late-stage parasitized cells than in the early-stage parasitized cells. Similar results were obtained for PE membrane distribution using either chemical (TNBS) or enzymatic (PLA2 plus SMC) methods, although changes in PS distribution were observed only with TNBS. Uninfected cohort cells derived from mixed populations of infected and uninfected cells exhibited normal patterns of membrane phospholipid organization. The observed alterations in P falciparum-infected red cell membrane phospholipid distribution, which is independent of the presence or absence of knobby protuberances, might be associated with the drastic changes in cell membrane permeability and susceptibility to early hemolysis observed in the late stages of parasite development.


Blood ◽  
1984 ◽  
Vol 64 (5) ◽  
pp. 1129-1134 ◽  
Author(s):  
Y Yawata ◽  
T Sugihara ◽  
M Mori ◽  
S Nakashima ◽  
Y Nozawa

Abstract Membrane lipid analyses and electron spin resonance (ESR) studies of membrane fluidity were carried out on the red cells of a Japanese patient with hereditary high red cell membrane phosphatidylcholine hemolytic anemia (HPCHA). Increased amounts of phosphatidylcholine (PC) and cholesterol were found in the membrane lipids of the affected patient, despite normal plasma lipids. The order parameter of cholesterol-free pure phospholipid liposomes prepared from this patient's red cells was decreased, apparently because of the increased PC. In contrast, the order parameter of the total red cell lipid liposomes (containing free cholesterol) was essentially normal. The overall fluidity of the intact red cells was determined by ESR with a spin probe, 5-SAL. Again, the order parameters were normal in the intact red cells of the patient with HPCHA. This suggests that the concomitant increase of membrane cholesterol and phosphatidylcholine serves to maintain normal membrane fluidity in the HPCHA red cells.


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