scholarly journals QUANTITATIVE ASPECTS OF THE SPONTANEOUS ELUTION OF INFLUENZA VIRUS FROM RED CELLS

1954 ◽  
Vol 99 (3) ◽  
pp. 251-260 ◽  
Author(s):  
Bernard Sagik ◽  
Theodore Puck ◽  
Seymour Levine

Each chick and human red cell contains approximately 300 sites capable of attaching influenza virus particles. These correspond to an area representing approximately 2 per cent of the red cell surface. Although the rate of attachment of PR8 to red cells is not diffusion-limited, when calculated on the basis of the total cell area, it does approach the theoretical maximum for interaction between the virus and the fraction of the cell area known to contain attachment sites. It is demonstrated that the virus attachment can initiate a spreading disturbance on the red cell membrane which extends over an area far exceeding that covered by the attached virus and which leads to the destruction of receptor sites. This process does not involve cyclic virus attachment, elution from the cell, and reattachment to another site. Practically all the receptor sites on a cell are destroyed before any virus is liberated into the medium. The spontaneous elution of virus from red cells within 24 hours at 37° C. requires a threshold value of at least 3 and less than 5 virus particles per cell. Parallelisms between the spontaneous elution reaction and the phenomenon of lysis-from-without in the bacteriophage system are demonstrated.

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.


1978 ◽  
Vol 72 (2) ◽  
pp. 249-265 ◽  
Author(s):  
B Sarkadi ◽  
J K Alifimoff ◽  
R B Gunn ◽  
D C Tosteson

This paper describes the kinetics and stoichiometry of a tightly coupled Na-Li exchange transport system in human red cells. The system is inhibited by phloretin and furosemide but not by ouabain. Li influx by this system increases and saturates with increasing concentrations of external Li and internal Na and is inhibited competitively by external Na. Comparable functions relate Li efflux and Na efflux to internal and external Li and Na concentrations. Analysis of these relations yields the following values for the ion concentrations required to half-maximally activate the transport system: internal Na and Li 9.0 and 0.5 mM, respectively, external Na and Li 25 and 1.5 mM, respectively. The system performs a 1:1 exchange of Na and Li moving in opposite directions across the red cell membrane. We found no evidence for a simultaneous transport of more than one Na and Li by the system. The maximum transport rate of Na-dependent Li transport varied between 0.1 and 0.37 mmol/(liter of cells X h) in the red cells of the five normal male subjects studied. No significant variations between individual subjects were observed for bicarbonate-stimulated Li transport and for the residual Li fluxes which occur in the absence of bicarbonate and in the presence of ouabain plus phloretin.


1988 ◽  
Vol 250 (2) ◽  
pp. 407-414 ◽  
Author(s):  
M J Tanner ◽  
S High ◽  
P G Martin ◽  
D J Anstee ◽  
P A Judson ◽  
...  

We have studied the DNA of individuals who express an altered sialoglycoprotein beta on their red cells by using Southern blotting with sialoglycoprotein-beta cDNA probes. Individuals of the Leach phenotype do not express any beta (sialoglycoprotein beta) or gamma (sialoglycoprotein gamma) on their red cells, and we show that about 7 kb of DNA, including the 3′ end of the beta gene, is deleted in this DNA. Any protein product of this gene is likely to lack the membrane-associating domain of beta. We have also examined the DNA of two types of other individuals (Yus-type and Gerbich-type) who have red cells that lack beta and gamma, but contain abnormal sialoglycoproteins related to beta. These two types of DNA contain different internal deletions of about 6 kb in the beta gene. We suggest that these deletions result from the presence of two different sets of internal homology in the beta gene, and on this basis we propose structures for the abnormal Yus-type and Gerbich-type sialoglycoproteins which are consistent with the other evidence that is available. We provide evidence that beta and gamma are products of the same gene and suggest a possible mechanism for the origin of gamma based on leaky initiation of translation of beta mRNA.


Blood ◽  
1988 ◽  
Vol 71 (5) ◽  
pp. 1427-1431 ◽  
Author(s):  
N Fortier ◽  
LM Snyder ◽  
F Garver ◽  
C Kiefer ◽  
J McKenney ◽  
...  

Abstract In vitro induced oxidative damage to normal human RBCs has previously been shown to result in increased membrane rigidity as a consequence of the generation of a protein complex between hemoglobin and spectrin. In order to determine if in vivo generated hemoglobin-spectrin complexes may play a role in increased membrane rigidity of certain pathologic red cells, we measured both these parameters in membranes prepared from hereditary xerocytosis (Hx), sickle cell disease (Sc), and red cells from thalassemia minor (beta thal). Membranes were prepared from density-fractionated red cells, and membrane deformability was measured using an ektacytometer. Hemoglobin-spectrin complex was determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel analysis, as well as by Western blot analysis using a monoclonal antibody against the beta- subunit of hemoglobin. For these three types of pathologic red cells, progressive cellular dehydration was associated with increased membrane rigidity and increased content of hemoglobin-spectrin complex. Moreover, the increase in membrane rigidity appeared to be directly related to the quantity of hemoglobin-spectrin complex associated with the membrane. Our findings imply that hemoglobin-spectrin complex is generated in vivo, and this in turn results in increased membrane rigidity of certain pathologic red cells. The data further suggest that oxidative crosslinking may play an important role in the pathophysiology of certain red cell disorders.


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.


Blood ◽  
1984 ◽  
Vol 64 (1) ◽  
pp. 305-307 ◽  
Author(s):  
T Asakura ◽  
Y Shibutani ◽  
MP Reilly ◽  
RH DeMeio

Abstract Potassium tellurite (K2TeO3) was found to be a potent antisickling agent that inhibited red cell sickling at concentrations less than 10 mumol/L. The inhibitory effect depended on the incubation time, with the effect increasing with longer incubation periods. Because tellurite causes swelling of red cells, and because the antisickling effect of tellurite correlated with the degree of red cell swelling, the antisickling effect of tellurite is assumed to be due to the decreased mean cell hemoglobin concentration. Swelling of red cells by tellurite was accelerated by the addition of reduced glutathione. Tellurite appears to be a new type of antisickling agent that interacts with the red cell membrane.


1989 ◽  
Vol 203 ◽  
pp. 381-400 ◽  
Author(s):  
D. Halpern ◽  
T. W. Secomb

An analysis is presented of the mechanics of red blood cells flowing in very narrow tubes. Mammalian red cells are highly flexible, but their deformations satisfy two significant constraints. They must deform at constant volume, because the contents of the cell are incompressible, and also at nearly constant surface area, because the red cell membrane strongly resists dilation. Consequently, there exists a minimal tube diameter below which passage of intact cells is not possible. A cell in a tube with this diameter has its critical shape: a cylinder with hemispherical ends. Here, flow of red cells in tubes with near-minimal diameters is analysed using lubrication theory. When the tube diameter is slightly larger than the minimal value, the cell shape is close to its shape in the critical case. However, the rear end of the cell becomes flattened and then concave with a relatively small further increase in the diameter. The changes in cell shape and the resulting rheological parameters are analysed using matched asymptotic expansions for the high-velocity limit and using numerical solutions. Predictions of rheological parameters are also obtained using the assumption that the cell is effectively rigid with its critical shape, yielding very similar results. A rapid decrease in the apparent viscosity of red cell suspensions with increasing tube diameter is predicted over the range of diameters considered. The red cell velocity is found to exceed the mean bulk velocity by an amount that increases with increasing tube diameter.


Blood ◽  
2003 ◽  
Vol 101 (3) ◽  
pp. 1194-1199 ◽  
Author(s):  
Kris Noel Dahl ◽  
Connie M. Westhoff ◽  
Dennis E. Discher

Abstract Interactions of CD47 and RhAG and the Rh proteins are visualized between one another and with the cytoskeleton of intact erythrocytes. In a first study, CD47 is labeled with a phycoerythrin (PhE)– tagged antibody, which generates discrete spots that reflect induced clusters of CD47. Rh and RhAG colocalize with each other and to these induced clusters, whereas Band 3 and glycophorin C remain more homogeneously dispersed on the cell periphery. In a second study, red cells are aspirated into a micropipette, and immunofluorescent maps of the surface gradients that develop for CD47 and RhAG determine cytoskeletal connectivity. CD47 and RhAG gradients on normal red cells prove to be nearly identical and also appear intermediate to those found for the fluid bilayer and network-linked glycophorin C. Similar gradients are obtained for CD47 on Rhnull cells, suggesting that linkage of CD47 to the spectrin-actin skeleton is independent of Rh or RhAG and is not affected by CD47's reduced surface expression on these cells. The results show that CD47 colocalizes with Rh and RhAG but is fractionally attached to the red cell membrane skeleton independent of these and other major integral membrane proteins involved in cytoskeletal attachment. The results imply a homogeneous base distribution of CD47, restrained by cytoskeleton linkages, plus a smaller fraction of CD47, which is able to diffuse in the membrane.


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