scholarly journals Schistosomula of Schistosoma mansoni use lysophosphatidylcholine to lyse adherent human red blood cells and immobilize red cell membrane components.

1986 ◽  
Vol 103 (3) ◽  
pp. 819-828 ◽  
Author(s):  
D E Golan ◽  
C S Brown ◽  
C M Cianci ◽  
S T Furlong ◽  
J P Caulfield

Human red blood cells (RBCs) adhere to and are lysed by schistosomula of Schistosoma mansoni. We have investigated the mechanism of RBC lysis by comparing the dynamic properties of transmembrane protein and lipid probes in adherent ghost membranes with those in control RBCs and in RBCs treated with various membrane perturbants. Fluorescence photobleaching recovery was used to measure the lateral mobility of two integral membrane proteins, glycophorin and band 3, and two lipid analogues, fluorescein phosphatidylethanolamine (Fl-PE) and carbocyanine dyes, in RBCs and ghosts adherent to schistosomula. Adherent ghosts manifested 95-100% immobilization of both membrane proteins and 45-55% immobilization of both lipid probes. In separate experiments, diamide-induced cross-linking of RBC cytoskeletal proteins slowed transmembrane protein diffusion by 30-40%, without affecting either transmembrane protein fractional mobility or lipid probe lateral mobility. Wheat germ agglutinin- and polylysine-induced cross-linking of glycophorin at the extracellular surface caused 80-95% immobilization of the transmembrane proteins, without affecting the fractional mobility of the lipid probe. Egg lysophosphatidylcholine (lysoPC) induced both lysis of RBCs and a concentration-dependent decrease in the lateral mobility of glycophorin, band 3, and Fl-PE in ghost membranes. At a concentration of 8.4 micrograms/ml, lysoPC caused a pattern of protein and lipid immobilization in RBC ghosts identical to that in ghosts adherent to schistosomula. Schistosomula incubated with labeled palmitate released lysoPC into the culture medium at a rate of 1.5 fmol/h per 10(3) organisms. These data suggest that lysoPC is transferred from schistosomula to adherent RBCs, causing their lysis.

1993 ◽  
Vol 76 (1) ◽  
pp. 13-22 ◽  
Author(s):  
H.S. Thatte ◽  
M.R. Kasschau ◽  
S.T. Furlong ◽  
M.P. Byamsmith ◽  
D.F. Williams ◽  
...  

1992 ◽  
Vol 117 (1) ◽  
Author(s):  
Anna Giuliani ◽  
Stefano Marini ◽  
Lucietta Ferroni ◽  
Patrizia Caprari ◽  
SaverioG. Cond� ◽  
...  

2008 ◽  
pp. 621-629
Author(s):  
E Tellone ◽  
S Ficarra ◽  
R Scatena ◽  
B Giardina ◽  
A Kotyk ◽  
...  

The effects of gemfibrozil (GFZ), an antihyperlipidemic agent, on the anionic transport of the human red blood cells (RBC) during the oxygenation-deoxygenation cycle were examined. Gemfibrozil clearly plays a role in the modulation of the anionic flux in erythrocytes; in fact it causes a strong increment of anions transport when the RBCs are in the high-oxygenation state (HOS). Such an effect is remarkably reduced in the lowoxygenation state (LOS). With the aim of identifying the dynamics of fibrate action, this effect has been investigated also in human ghost and chicken erythrocytes. These latter, in fact, are known to possess a B3 (anion transporter or Band 3) modified at the cytoplasmic domain (cdb3) which plays a significant role in the metabolic modulation of red blood cells. The results were analyzed taking into account the well-known interactions between fibrates and both conformational states of hemoglobin i.e. the T state (deoxy-conformation) and the R state (oxy-conformation). The effect of gemfibrozil on anionic influx appears to be due to a wide interaction involving a “multimeric” Hb-GFZ-cdb3 macromolecular complex.


2001 ◽  
Vol 34 (3) ◽  
pp. 143 ◽  
Author(s):  
José A. Jordán ◽  
F. Javier Alvarez ◽  
L. Alfredo Lotero ◽  
Angel Herráez ◽  
José C. Díez ◽  
...  

2013 ◽  
Vol 98 (6) ◽  
pp. 2494-2501 ◽  
Author(s):  
Luciana Bordin ◽  
Gabriella Donà ◽  
Chiara Sabbadin ◽  
Eugenio Ragazzi ◽  
Alessandra Andrisani ◽  
...  

Context: Aldosterone (Aldo) effects include NADPH oxidase activation involved in Aldo-related oxidative stress. Red blood cells (RBCs) are particularly sensitive to oxidative assault, and both the formation of high molecular weight aggregates (HMWAs) and the diamide-induced Tyr phosphorylation (Tyr-P) level of membrane band 3 can be used to monitor their redox status. Objective: The Aldo-related alterations in erythrocytes were evaluated by comparing in vitro evidence. Design: This was a multicenter comparative study. Study Participants: The study included 12 patients affected by primary aldosteronism (PA) and 6 healthy control subjects (HCs), whose RBCs were compared with those of patients with PA. For in vitro experiments, RBCs from HCs were incubated with increasing Aldo concentrations. Main Outcome Measures: The Tyr-P level, band 3 HMWA formation, and autologous IgG binding were evaluated. Results: In patients with PA, both Tyr-P levels and band 3 HMWAs were higher than those in HCs. RBCs from HCs were treated with increasing Aldo concentrations in both platelet-poor plasma (PPP) and charcoal-stripped (CS)-PPP. Results showed that Aldo had dose- and time-dependent effects on band 3 Tyr-P and HMWA formation in CS-PPP more than in PPP. These effects were almost completely prevented by canrenone or cortisol. Aldo-related membrane alterations led to increased autologous IgG binding. Conclusions: Erythrocytes from patients with PA show oxidative-like stress evidenced by increased HMWA content and diamide-induced band 3 Tyr-P level. Aldo effects are mediated by the mineralocorticoid receptor, as suggested by the inhibitory effects of canrenone, an antagonist of Aldo. In CS-PPP, in which Aldo induces remarkable membrane alterations leading to IgG binding, Aldo may be responsible for premature RBC removal from circulation.


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