Unsaturated vitamin B12 binding capacity of human serum studied by gel filtration

1970 ◽  
Vol 27 (2) ◽  
pp. 251-257 ◽  
Author(s):  
Ragnhild Gullberg
Blood ◽  
1962 ◽  
Vol 19 (2) ◽  
pp. 229-235 ◽  
Author(s):  
LEO M. MEYER ◽  
EUGENE P. CRONKITE ◽  
INEZ F. MILLER ◽  
CLAIRE W MULZAC ◽  
IRVING JONES

Abstract 1. Mature neutrophilic leukocytes show the highest Co60B12 binding capacity. 2. Less mature granulocytes, "blast" forms and eosinophils have little or no Co60B12 binding capacity. 3. Disintegrated mature leukocytes from chronic myelocytic leukemia and polycythemia vera show higher B12 binding capacity than intact cells. 4. Mature leukocytes from patients with chronic myelocytic leukemia and polycythemia vera show a two-phase B12 curve suggesting specific and nonspecific binding, similar to that observed in human serum. 5. Disintegration products from mature neutrophilic leukocytes probably contribute largely to increased B12 binding capacity of serum in chronic myelocytic leukemia and polycythemia vera.


Blood ◽  
1969 ◽  
Vol 34 (6) ◽  
pp. 774-781 ◽  
Author(s):  
CHRISTINE LAWRENCE

Abstract 57CoB12 was added to serum in vitro to study its binding by the three known serum B12-binders in patients with vitamin B12 deficiency and in normal controls. Gel filtration through columns of Sephadex G-200 was used to separate the low (beta) and high (alpha1 and beta) molecular weight B12-binding fractions. Electrophoresis on filter paper was used to separate the alpha1- and beta-globulins. The alpha1-globulin fraction in the serum of B12-deficient patients bound more of the added 57CoB12 than did this fraction in normal serum, presumably because this binder of the serum endogenous vitamin B12 is much less saturated in B12-deficiency. However, the total B12 binding capacity of the alpha1-globulin (for endogenous plus added vitamin B12) was lower in B12-deficient than in normal serum. The low molecular weight beta-binder bound more added 57CoB12 in B12-deficient than in normal serum, whereas the high molecular weight beta binder had a much lower B12-binding capacity in deficient than in normal serum. These abnormalities were independent of the cause of the vitamin B12 deficiency and disappeared after successful treatment with vitamin B12.


Blood ◽  
1971 ◽  
Vol 37 (3) ◽  
pp. 360-366 ◽  
Author(s):  
RALPH CARMEL ◽  
CHARLES A. COLTMAN

Abstract Granulocytes are rich in vitamin B12-binding protein resembling serum alpha-globulin binder. Lymphocytes and erythrocytes contain lesser amounts of the protein, but monocytes have not heretofore been studied. Characterization of our patient’s monocytic B12 binder by gel filtration, radioautography, immunologic studies, and mediation of reticulocyte uptake of vitamin B12 showed it was identical to granulocytic binder. Monocytic B12-binding was low, but, due to the monocytosis in the subject, monocytes accounted for more total binding than did her granulocytes. The serum had markedly elevated B12-binding capacity. However, the elevation was of beta-globulin primarily. The reason for this remains unclear. In vitro incubation of cellular extract with serum did not alter the characteristics of the cellular B12-binding protein.


1973 ◽  
Vol 30 (02) ◽  
pp. 414-424 ◽  
Author(s):  
Ulla Hedner

SummaryA procedure is described for partial purification of an inhibitor of the activation of plasminogen by urokinase and streptokinase. The method involves specific adsorption of contammants, ion-exchange chromatography on DEAE-Sephadex, gel filtration on Sephadex G-200 and preparative electrophoresis. The inhibitor fraction contained no antiplasmin, no plasminogen, no α1-antitrypsin, no antithrombin-III and was shown not to be α2 M or inter-α-inhibitor. It contained traces of prothrombin and cerulo-plasmin. An antiserum against the inhibitor fraction capable of neutralising the inhibitor in serum was raised in rabbits.


1977 ◽  
Vol 38 (02) ◽  
pp. 0494-0503 ◽  
Author(s):  
D. S Pepper ◽  
D Banhegyi ◽  
J. D Cash

SummaryAntithrombin III (AT III) complexes were isolated from human serum by affinity chromatography and gel filtration. In the first step of the preparation, using heparin-agarose chromatography, we observed that the complexed form of AT III bound less strongly to the gel than the free form and that about half of the AT III was free. With further purification a 2.5 × 105 molecular weight complex was isolated. Using 125I labelled human thrombin, this complex was radioactive indicating the presence of thrombin. Only in a synthetic thrombin-AT III system was a 9 × 104 molecular weight complex detected, but not in serum. These facts suggest that in serum AT III complexes may exist in a polymeric form. Also, an AT III antigen derived from the original AT III molecule, but not complexed, was isolated which may be a degradation product.Abbreviations used: AT-III, antithrombin III. Hepes, N-2-Hydroxyethylpiperazine-N-2-Ethanesulphonic acid.


1975 ◽  
Vol 142 (5) ◽  
pp. 1065-1077 ◽  
Author(s):  
A.P. Osmand ◽  
R.F. Mortensen ◽  
Joan Siegel ◽  
H. Gewurz

Interactions of CRP with various substrates in the presence of human serum have been shown to result in efficient activation of C components C1-C5. We now report the ability of CRP to initiate C-dependent hemolysis. For this purpose CRP was isolated by affinity chromatography using pneumococcal CPS and gel filtration; its purity was established by several criteria. Erythrocytes were coated with CPS (E-CPS) and passively sensitized with CRP. C-dependent lysis of these cells was observed upon the addition of suitably absorbed human serum, and the efficiency of hemolysis compared favorably with that initiated by rabbit IgG anti-CPS antibody. CRP also sensitized E-CPS for lysis by guinea pig C; partial lysis was seen when C4-deficient guinea pig serum was used, suggesting that CRP also shares with antibody the ability of CRP to fully activate the C system and provide further evidence for a role for CRP similar to that of antibody in the initiation and modulation of inflammatory reactions via the complete system.


1972 ◽  
Vol 71 (3) ◽  
pp. 443-453 ◽  
Author(s):  
Olav Trygstad ◽  
Irene Foss

ABSTRACT A lipid-mobilizing factor (LMF) with an adipotrophic effect in human and animal fat tissue has been prepared from human pituitary glands. The addition of normal human serum to LMF reduced its lipolytic effect, and it was completely abolished by serum from a group of obese patients, whereas the lipolysis was not influenced by serum from patients with generalized lipodystrophy. By DEAE-cellulose chromatography of human serum the inhibitory effect on LMF was found to be present in a protein fraction less acidic than the main serum albumin fraction. The inhibitory fraction was deprived of some contaminants by Sephadex gel filtration. Disc electrophoresis demonstrated the presence of three components in the inhibitory protein (IP), and they were identified as albumin, transferin, and haemopexin by immuno-electrophoresis. Precipitation of these proteins by their rabbit antisera demonstrated that the inhibitory effect was present in the albumin fraction. Insulin like activity was not observed in IP. A protein binding of LMF by IP could not be demonstrated. Incubation at 37°C for one hour of a mixture of LMF and IP eliminated the electrophoretic picture of LMF. It is concluded that the inhibitory effect of human serum may be due to proteolysis of LMF.


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