Phospholipid Requirement for Rh Antigen Activity

2015 ◽  
pp. 34-37
Author(s):  
F. A. Green
Keyword(s):  
Antigen Activity

α2-Antiplasmin: Functional Characterization and Metabolism in a Heterozygote Deficient Patient

1986 ◽  
Vol 55 (03) ◽  
pp. 375-378 ◽  
Author(s):  
E A R Knot ◽  
J W ten Cate ◽  
R J Lamping ◽  
Liem Kian Gie
Keyword(s):  
Half Life ◽  
Functional Characterization ◽  
Bleeding Tendency ◽  
Normal Range ◽  
Crossed Immunoelectrophoresis ◽  
Synthetic Rate ◽  
Catabolic Rate ◽  
Deficient Patient ◽  
Antigen Activity ◽  
Bleeding History

SummaryAn 81-year-old male with a mild life-long bleeding history and an α2-antiplasmin (α2-AP) plasma level of 55% biological activity and 41% antigen activity (normal range 80-140%) was studied. The ratio of plasminogen binding (PB): non-plasminogen binding (NPB) α2-AP assayed by modified crossed immunoelectrophoresis (CIE) was 7.3/2.7 (controls 6.3 ± 0.49 SD/3.7 ± 0.49 SD). The patient’s α2-AP showed decreased affinity for fibrin, i. e. 8.3% versus 32.4% of normal control α2-AP associated with fibrin during clotting of plasma. A metabolic study performed with human purified 125I-α2-AP(PB/NPB 7.7/2.3) showed a plasma radioactivity disappearance half-life of 72.9 h (n 60.1 ± 5.3 h) with a normal fractional catabolic rate and a reduced absolute catabolic (synthetic) rate of 0.70 mg/kg/day (n 2.10 ± 0.60 mg/kg/day). The exchange between the central and third compartment was increased. The increased α2-AP PB form and the increased plasma radioactivity disappearance half-life are suggestive of a slower conversion of the PB form into the NPB form and/or slower degradation of the PB form. The bleeding tendency in this patient could be explained by decreased synthesis of α2-AP and decreased binding to fibrin.

The Role of Membrane Phospholipid in Expression of Erythrocyte Rh0(D) Antigen Activity

1980 ◽  
Vol 164 (4) ◽  
pp. 561-568 ◽  
Author(s):  
F. V. Plapp ◽  
M. M. Kowalski ◽  
J. P. Evans ◽  
L. L. Tilzer ◽  
M. Chiga
Keyword(s):  
Membrane Phospholipid ◽  
Antigen Activity ◽  
D Antigen

Plasminogen Activity in Plasma and in Serum Before and After Venostasis

1979 ◽  
Author(s):  
C. Soria ◽  
A. Rodriguez-Zeballos ◽  
J. Soria ◽  
G. Kartalis
Keyword(s):  
Biological Activity ◽  
Synthetic Substrate ◽  
Lysis Time ◽  
Before And After ◽  
Euglobulin Lysis Time ◽  
Antigen Activity ◽  
Fibrin Clots

When venostasis is applied in men for 10 minutes at a pressure half-way between diastolic and systolic, various results may be obtained as far as fibrinolysis is concerned, normally the euglobulin lysis time reduced from above 3 hours to less than one hour. In these conditions, after venostasis the estimation of plasminogen after activation by Streptokinase (S.K.) on synthetic substrate S2251, shows 20-80% greater activity in serum than in plasma. In some patients at high risks of thrombosis, the euglobulin lysis time 15 unchanged after venostasis. In these cases, the biological activity of plasminogen is slightly greater in plasma than in serum, as is observed before venostasis in all subjects.In order to explain these observations, experiments were performed using placental or plasmatic (glu or lys) plasminogen ; these show that for the same antigen activity, the biological activity of placental plasminogen previously activated by S.K. is greater than that of plasmatic plasminogen. We suggest a modification of the structure of plasminogen in the presence of activators and of fibrin clots. Further experiments will be necessary to explain the modification of plasminogen structure

scholarly journals Human erythrocyte antigens: II. The In(Lu) gene regulates expression of an antigen on an 80-kilodalton protein of human erythrocytes

Blood ◽  
1984 ◽  
Vol 64 (3) ◽  
pp. 599-606 ◽  
Author(s):  
MJ Telen ◽  
TJ Palker ◽  
BF Haynes
Keyword(s):  
Monoclonal Antibody ◽  
Western Blot ◽  
Erythrocyte Membrane ◽  
Human Erythrocyte ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Protein A ◽  
Sodium Dodecyl ◽  
Two Dimensions ◽  
Antigen Activity

Abstract We have previously shown that a murine monoclonal antibody (A3D8) identifies a human erythrocyte protein antigen whose expression is regulated by the Lutheran inhibitor [In(Lu)] gene. In the present study, we demonstrated by immunoprecipitation and Western blot techniques that the antigen defined by A3D8 was on an 80-kD erythrocyte membrane protein. A second 170-kD protein was coprecipitated with the 80-kD protein but failed to show antigen activity by Western blot analysis. The 170-kD protein, when analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis in two dimensions, was composed of 50- and 30-kD disulfide-linked subunits. In(Lu) Lu[a-b-) erythrocytes differed from Lu(a+b+) or Lu(a-b+) erythrocytes in that In(Lu) deoxycholate erythrocyte membrane extracts contained trace amounts of immunoprecipitable 80-kD protein compared with detergent-solubilized erythrocyte membrane extracts prepared from Lu(a+b+) or Lu(a-b+) subjects.

Functional Cell Surface Expression of Band 3, the Human Red Blood Cell Anion Exchange Protein (AE1), in K562 Erythroleukemia Cells: Band 3 Enhances the Cell Surface Reactivity of Rh Antigens

Blood ◽  
1998 ◽  
Vol 92 (11) ◽  
pp. 4428-4438 ◽  
Author(s):  
Roland Beckmann ◽  
Jonathan S. Smythe ◽  
David J. Anstee ◽  
Michael J.A. Tanner
Keyword(s):  
Cell Surface ◽  
Chloride Transport ◽  
K562 Cells ◽  
Surface Expression ◽  
Band 3 ◽  
Surface Reactivity ◽  
Cell Surface Expression ◽  
Anion Exchanger 1 ◽  
Erythroleukemia Cells ◽  
Antigen Activity

Human K562 erythroleukemia cells were transfected with human band 3 (anion exchanger 1 [AE1]) cDNA, using the pBabe retroviral vector. Stable K562 clones expressing band 3 were isolated by flow cytometry, and surface expression was quantified by immunoblotting. The function of band 3 expressed at the cell surface was demonstrated in chloride transport assays. K562 cells expressing band 3 also displayed high levels of the Wrb blood group antigen, confirming the role of band 3 in Wrb expression, and an increase in the low levels of endogenous Rh antigen activity. We also performed coexpression experiments with K562 clones that had previously been transduced with cDNAs encoding RhD or RhcE polypeptides. The transfection and expression of band 3 in these clones substantially increased the levels of RhD and cE antigen activity expressed on the cells and also increased the reactivity of the cells with antibody to the endogenous Rh glycoprotein (RhGP, Rh50). The increased reactivity of Rh antigens may result from cell surface or intracellular interactions of band 3 with the protein complex which contains the Rh polypeptides and RhGP, or from indirect effects of band 3 on the membrane environment. This work establishes a system for cell surface expression of band 3 in a mammalian cell line, which will enable further studies of the protein and its interactions with other membrane components.

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