Isolation of Low-Molecular-Weight Heparin/Heparan Sulfate from Marine Sources

2014 ◽  
pp. 45-60 ◽  
Author(s):  
Ramachandran Saravanan
Keyword(s):  
Molecular Weight ◽  
Heparan Sulfate ◽  
Low Molecular Weight Heparin ◽  
Low Molecular Weight

Enhancing Effects of Heparin/Low Molecular Weight Heparin/Heparan Sulfate on Antigen Presentation and Antigen-Specific Cytotoxic T Lymphocyte (CTL) Induction by Monocyte-Derived Dendritic Cells.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3816-3816
Author(s):  
Asuka Sekiguchi ◽  
Miwako Narita ◽  
Toshio Yano ◽  
Naoko Sato ◽  
Anri Saito ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Heparan Sulfate ◽  
Antigen Presentation ◽  
Binding Sites ◽  
Low Molecular Weight Heparin ◽  
Target Cells ◽  
Low Molecular Weight ◽  
Heparin Binding ◽  
Antigen Presenting ◽  
Ctl Induction

Abstract Heparin is bound with heparin-binding sites on certain cells, which induces proliferation and differentiation signals. In addition, heparin is bound with heparin-binding domains of various cytokines, which enhances the interaction between cytokines and target cells. Monocytes have been demonstrated to posses heparin-binding sites on cell surfaces. In the present study, we investigated the effects of heparin (including low molecular weight heparin) and heparan sulfate on antigen presentation and antigen-specific CTL induction of monocyte-derived DCs. Peripheral blood CD14+ cells were cultured to generate immature and mature DCs with various concentrations of heparin, low molecular weight heparin or heparan sulfate. Cultured cells were analyzed for DC-associated surface phenotypes by flow cytometry and evaluated for allogeneic antigen presenting ability by mixed leukocyte culture. In order to evaluate the effects of heparin on monocyte-derived DCs to generate antigen-specific CTL, DCs were generated from HLA-A2402 donors by serum-free culture with heparin, transfected with in vitro transcribed WT-1 mRNA on day 6 and cultured with the addition TNF-α/IL-1α/IL-6/IFN-γ/PGE2 for further 1 day. WT-1 mRNA-transfected DCs were used for priming autologous lymphocytes in co-culture at the stimulator:responder ratio of 1:10. Lymphocytes were primed with the same DCs 2-3 times in the interval of 5-7 days. CD8+ T cells were separated and used as effector cells in 51Cr-release assay. WT-1 expressing and HLA-A24+ cell line MegO1 was used as target cells. In order to evaluate the association of MHC molecules in the cytotoxicity, 51Cr-lebelled target cells were treated with anti-MHC class I or class II monoclonal antibody before cytotoxicity assay. In order to evaluate the antigen specificity of the generated CTL, unlabelled target cells were added to the cytotoxicity assay. By the addition of heparin, the expression of CD1a and CD80 on both immature and mature DCs was markedly enhanced and the allogeneic antigen presenting ability was elevated in both immature and mature DCs. By the addition of low molecular weight heparin, the expression of CD1a was enhanced and antigen presenting ability was elevated also. By the addition of heparan sulfate, similar results of elevated antigen presentation were obtained. By the priming of lymphocytes with WT-1 mRNA transfected DCs generated from monocytes by the serum-free culture with heparin, cytotoxic capability against WT-1 expressing target cells was demonstrated in the primed lymphocytes. The cytotoxic capability of the lymphocytes was blocked by the treatment of the target cells with anti-MHC class I monoclonal antibody and the addition of unlabelled target cells in the cytotoxicity reaction. The present study demonstrated that heparin/low molecular weight heparin/heparan sulfate could enhance the antigen presentation and antigen-specific CTL induction of monocyte-derived DCs. These findings suggest the usefulness of heparin for generating efficient DCs for DC-based immunotherapy and the involvement of heparan sulfate in immunological defense mechanism.

Low-molecular-weight heparin in the prevention and treatment of thromboembolic disorders

1998 ◽  
Vol 1 (5) ◽  
pp. 166-174 ◽  
Author(s):  
Evelyn R Hermes De Santis ◽  
Betsy S Laumeister ◽  
Vidhu Bansal ◽  
Vandana Kataria ◽  
Preeti Loomba ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight Heparin ◽  
Low Molecular Weight ◽  
Prevention And Treatment

Effects of Low Molecular Weight Heparin and Unfragmented Heparin on Induction of Osteoporosis in Rats

1990 ◽  
Vol 63 (03) ◽  
pp. 505-509 ◽  
Author(s):  
Thomas Mätzsch ◽  
David Bergqvist ◽  
Ulla Hedner ◽  
Bo Nilsson ◽  
Per Østergaar
Keyword(s):  
Molecular Weight ◽  
Bone Mineral ◽  
Low Molecular Weight Heparin ◽  
Zinc Content ◽  
Low Molecular Weight ◽  
Dependent Manner ◽  
Bone Mineral Mass ◽  
Bone Ash ◽  
Dose Dependent ◽  
Mineral Mass

SummaryA comparison between the effect of low molecular weight heparin (LMWH) and unfragmented heparin (UH) on induction of osteoporosis was made in 60 rats treated with either UH (2 IU/ g b w), LMWH in 2 doses (2 Xal U/g or 0.4 Xal U/g) or placebo (saline) for 34 days. Studied variables were: bone mineral mass in femora; fragility of humera; zinc and calcium levels in serum and bone ash and albumin in plasma. A significant reduction in bone mineral mass was found in all heparin-treated rats. There was no difference between UH and LMWH in this respect. The effect was dose-dependent in LMWH-treated animals. The zinc contents in bone ash were decreased in all heparin-treated rats as compared with controls. No recognizable pattern was seen in alterations of zinc or calcium in serum. The fragility of the humera, tested as breaking strength did not differ between treatment groups and controls. In conclusion, if dosed according to similar factor Xa inhibitory activities, LMWH induces osteoporosis to the same extent as UH and in a dose-dependent manner. The zinc content in bone ash was decreased after heparin treatment, irrespective of type of heparin given.

Markers of Hemostatic System Activation in Acute Deep Venous Thrombosis-Evolution during the First Days of Heparin Treatment

1993 ◽  
Vol 70 (06) ◽  
pp. 0909-0914 ◽  
Author(s):  
Keyword(s):  
Molecular Weight ◽  
Venous Thrombosis ◽  
Deep Venous Thrombosis ◽  
Unfractionated Heparin ◽  
Low Molecular Weight Heparin ◽  
Factor Xa ◽  
Low Molecular Weight ◽  
Dose Adaptation ◽  
Heparin Treatment ◽  
Lung Scan

SummaryFibrin D-Dimer (D-Di), prothrombin activation fragment (F 1+2) and thrombin-antithrombin III complexes (TAT) were measured using ELISA procedures in the plasma of patients with an acute deep venous thrombosis (DVT), at presentation and on days 2, 6 and 10 after initiation of heparin treatment. Patients were randomly allocated into two treatment groups: 44 patients received adapted doses of continuous intravenous unfractionated heparin (UH) whereas 47 received 1 mg/kg every twelve hours of a low molecular weight heparin (enoxaparin) subcutaneously. A phlebography and a perfusion lung scan were performed before inclusion and on day 10. Failure of therapy (n = 9) was defined by venogram worsening or confirmed pulmonary embolism. Improvement (n = 44) or stationary state (n = 38) were defined by venogram evolution in the absence of new leg scan defects.At presentation, D-Di, F 1 + 2 and TAT were above cut-off values in 97, 66 and 89% of patients respectively. D-Di levels correlated with the extent of venous thrombosis whereas TAT and F 1 + 2 did not. Mean levels of D-Di decreased sharply during the first days of treatment but were still abnormal on day 10. A secondary increase of D-Di on days 6 or 10 by more than 3 μg/ml occurred in 4 of the 9 patients who developed a thromboembolic recurrence but in none of the 72 patients who had a more favorable outcome. F 1 + 2 and TAT time-courses were not related to clinical evolution. In the Enoxaparin group, there was no relationship between antifactor Xa activities and any biological markers. TAT and F 1 + 2 levels fell on day 2 and remained stable until day 10. In contrast, in the UH group, TAT and F 1 + 2 did not significantly decrease on day 2, probably due to a delay in dose adaptation, but they declined slowly until day 10.In conclusion, D-Di displays a higher sensitivity than F 1 + 2 or TAT for the diagnosis of D\T. D-Di, but not TAT or F 1 + 2, follow-up seems to be of potential value for early detection of recurrency. Hemostatic activation is controlled earlier by fixed doses of a low molecular weight heparin, irrespective of the plasma anti-factor Xa activities, than by unfractionated heparin at adapted doses.

Effects of Unfractionated and Low Molecular Weight Heparins on Platelet Thromboxane Biosynthesis “In Vivo”

1994 ◽  
Vol 72 (06) ◽  
pp. 942-946 ◽  
Author(s):  
Raffaele Landolfi ◽  
Erica De Candia ◽  
Bianca Rocca ◽  
Giovanni Ciabattoni ◽  
Armando Antinori ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Unfractionated Heparin ◽  
Low Molecular Weight Heparin ◽  
Primary Source ◽  
In Vivo Studies ◽  
Low Molecular Weight ◽  
Heparin Administration ◽  
To Receive

SummarySeveral “in vitro” and “in vivo” studies indicate that heparin administration may affect platelet function. In this study we investigated the effects of prophylactic heparin on thromboxane (Tx)A2 biosynthesis “in vivo”, as assessed by the urinary excretion of major enzymatic metabolites 11-dehydro-TxB2 and 2,3-dinor-TxB2. Twenty-four patients who were candidates for cholecystectomy because of uncomplicated lithiasis were randomly assigned to receive placebo, unfractionated heparin, low molecular weight heparin or unfractionaed heparin plus 100 mg aspirin. Measurements of daily excretion of Tx metabolites were performed before and during the treatment. In the groups assigned to placebo and to low molecular weight heparin there was no statistically significant modification of Tx metabolite excretion while patients receiving unfractionated heparin had a significant increase of both metabolites (11-dehydro-TxB2: 3844 ± 1388 vs 2092 ±777, p <0.05; 2,3-dinor-TxB2: 2737 ± 808 vs 1535 ± 771 pg/mg creatinine, p <0.05). In patients randomized to receive low-dose aspirin plus unfractionated heparin the excretion of the two metabolites was largely suppressed thus suggesting that platelets are the primary source of enhanced thromboxane biosynthesis associated with heparin administration. These data indicate that unfractionated heparin causes platelet activation “in vivo” and suggest that the use of low molecular weight heparin may avoid this complication.

Sign in / Sign up

Export Citation Format

Share Document