Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Spleens from mice immunized with either human von Willebrand factor, albumin or fragment DD from plasminolyzed fibrin were divided into two equal parts. Subsequently, one half of the spleen cells were fused directly with X-63 mouse myeloma cells and the other half fused after freezing and thawing. The results show that hybridomas may successfully be prepared from frozen/thawn spleen cells, but that a higher cell density than with fresh cells is required. The possibility of making use of frozen spleen cell material implies that valuable time and cell material can be saved, and that fusions can be postponed and performed at the time of choice.
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PMID:Hybridomas can successfully be prepared from frozen/thawn spleen cells. 181 75

A case of acquired von Willebrand disease (AvWD) associated with an IgA lambda multiple myeloma is reported. No form of inhibitor could be detected. SDS-agarose gel electrophoresis patterns of von Willebrand factor (vWF) both in plasma and platelet lysates were normal but a decrease in all-sized multimers with a type IA pattern was seen. After 1-deamino-8-D arginine vasopressin (DDAVP) infusion, vWF multimers larger than those seen in the resting state appeared in patient plasma, which were progressively cleared. Indirect immunofluorescence studies with a monoclonal antibody to vWF showed that vWF was selectively absorbed into myelomatous cells. This is the first case of AvWD associated with multiple myeloma resulting from the selective absorption of vWF into abnormal plasma cells. This feature established a new pathophysiological mechanism of AvWD in multiple myeloma and probably in other lymphoproliferative diseases.
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PMID:Acquired von Willebrand disease in multiple myeloma secondary to absorption of von Willebrand factor by plasma cells. 220 95

Impaired platelet aggregation, normal shape change, and agglutination and normal ATP secretion and thromboxane synthesis in response to high concentrations of thrombin or arachidonic acid were found in a patient with multiple myeloma and hemorrhagic tendency. The purified IgG1 kappa or its F(ab1)2 fragments induced similar changes when added in vitro to platelet-rich plasma from normal subjects. In addition, the paraprotein inhibited adhesion to glass microbeads, fibrin clot retraction, and binding of radiolabeled fibrinogen or von Willebrand factor to platelets exposed to thrombin or arachidonic acid without affecting intraplatelet levels of cAMP. The radiolabeled para-protein bound to an average of 35,000 sites on normal platelets but it bound to less than 2,000 sites on the platelets from a patient with Glanzmann's thrombasthenia. Immunoprecipitation studies showed that the platelet antigen identified by the paraprotein was the glycoprotein IIIa. Furthermore, binding of radiolabeled prostaglandin E1 (PGE1) to resting platelets as well as binding of von Willebrand factor to platelets stimulated with ristocetin were entirely normal in the presence of patient's inhibitor. These studies indicate that bleeding occurring in dysproteinemia may be the result of a specific interaction of monoclonal paraproteins with platelets. In addition, our data support the concept that the interaction of fibrinogen and/or von Willebrand factor with the platelet glycoprotein IIb-IIIa complex is essential for effective hemostasis.
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PMID:A myeloma paraprotein with specificity for platelet glycoprotein IIIa in a patient with a fatal bleeding disorder. 293 59

The authors present a study of a human myeloma-produced monoclonal protein (IgG-k) directed against von Willebrand factor that caused an acquired von Willebrand's disease (vWD)-like syndrome. The illness was characterized by upper gastrointestinal bleeding, prolonged bleeding time, decreased platelet adhesiveness, lack of platelet aggregation in response to ristocetin, and a qualitatively abnormal Factor VIII related antigen (vWF) by two-dimensional immunoelectropheresis. Patient plasma or IgG fraction mixed with normal platelet-rich plasma completely inhibited aggregation with ristocetin, but patient platelets resuspended in normal plasma aggregated normally with ristocetin. VWF was markedly elevated and the two-dimensional immunoelectropheresis of vWF revealed a vWD type II-like pattern with an absence of the higher molecular weight forms of the vWF. Marked inhibitory activity was observed in the ristocetin cofactor assay but disappeared at the highest dilutions of patient plasma used in the assay. Infusion of cryoprecipitate following plasmapheresis led to a correction of the bleeding time, improvement in platelet adhesiveness, transient disappearance of inhibitory activity in the Factor VIII ristocetin cofactor assay, and no significant normalization of two-dimensional immunoelectropheresis of vWF. This case demonstrated a myeloma-associated monoclonal antibody that interacted specifically with that part of the Factor VIII molecule necessary for Factor VIII ristocetin cofactor activity, normal platelet adhesiveness, and bleeding time.
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PMID:A human myeloma-produced monoclonal protein directed against the active subpopulation of von Willebrand factor. 307 26

The response to a single intravenous infusion of 1-deamino-8-D-arginine vasopressin (DDAVP, desmopressin) was studied in two patients with acquired von Willebrand syndrome associated with IgG-kappa myeloma. Following infusion of DDAVP (0.3-0.4 micrograms/kg), prolonged bleeding time was normalized; plasma ristocetin cofactor activity, von Willebrand factor antigen, and factor VIII activity were remarkably increased; and high-molecular-weight forms of von Willebrand factor were demonstrated by crossed immunoelectrophoresis in both patients. Excellent hemostasis was achieved following administration of DDAVP in one patient when it was used for the treatment of gum bleeding and for the prophylaxis of bleeding during and after dental extractions. These observations suggest that DDAVP is an effective alternative to blood products for at least some patients with acquired von Willebrand syndrome in addition to patients with inherited von Willebrand disease, hemophilia A, and uremia.
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PMID:DDAVP in acquired von Willebrand syndrome associated with multiple myeloma. 308 86

Partially purified preparations of porcine factor VIII:C were used to immunize mice and spleen cells from the immunized animals were fused to NS-1 mouse myeloma cells. The ability of hybrid culture fluids to bind factor VIII:C was detected with a radiolabelled, affinity-purified, human antihuman VIII:C inhibitor. Three cloned hybrid lines have been obtained that preferentially bind to VIII:C when compared to von Willebrand factor binding. Two of these monoclonal antibodies partially inhibit VIII:C coagulant activity. The third antibody does not inhibit VIII:C, but it can be used as an affinity reagent to absorb dissociated VIII:C out of solution. Active coagulant can be recovered by elution in 50% ethylene glycol. The VIII:C obtained has a specific activity of 6 units/micrograms based on absorbance measurements. When analyzed on SDS gels, the unactivated VIII:C contains 3 bands of apparent molecular weight 166,000, 130,000 and 76,000. Thrombin treatment results in a 40 fold increase in activity and cleavage to products of 76,000, 67,000 an 50,000 and small amounts of lower molecular weight peptides. EDTA inactivation of the factor VIII:C results in the separation of the 166,000 and 130,000 chains from the 76,000 chain, suggesting a Ca++ dependent noncovalent interaction among the chains.
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PMID:Monoclonal antibodies to porcine factor VIII coagulant and their use in the isolation of active coagulant protein. 680 Apr 19

The behaviour of the factor VIII/von Willebrand factor complex (VIII:C, VIIIR:Ag and VIIIR:RCof) was investigated in 23 patients with secretory myeloma, in 2 patients with non-secretory myeloma and in 5 patients with macroglobulinemia. In most patients (21 of 25 patients with plasma cell myeloma and 2 of 5 patients with macroglobulinemia) VIIIR:Ag was increased usually without corresponding increases in VIII:C and VIIIR:RCof. There was no correlation between the VIIIR:Ag levels and paraprotein Ig type or level nor with the presence or the absence of Bence Jones proteins in serum and urine. Furthermore, increased levels of VIIIR:Ag were found in patients with non-secretory myeloma. In general, VIIIR:Ag was higher in patients with extensive bone lesions and there was a significant correlation between cell mass and the VIIIR:Ag level. The crossed-immunoelectrophoresis of plasmas with discrepant VIIIR:Ag and VIIIR:RCof showed variation from the normal pattern.
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PMID:Factor VIII complex in myelomatosis and related disorders. 681 70

Acquired von Willebrand disease (vWD) has been described in a few patients with multiple myeloma. The present study characterizes an inhibitor of von Willebrand factor (vWF) isolated from a patient with multiple myeloma (IgG-kappa). Multimeric analysis of vWF from this patient's plasma showed a reduction in multimers of all sizes. The inhibitor (IgG) detected only the vWF subunit from plasma of normal individuals. It reacted with intact vWF subunit and a 39/34kDa dispase-digested fragment of vWF (residues; Leu480/Val481-Gly718), but did not react with platelet membrane glycoproteins (GPs) or adhesive proteins. The binding of vWF to GPIb mediated by ristocetin and by botrocetin was inhibited by the patient's IgG with an IC50s of 0.3 mg/ml and 0.48 mg/ml, respectively. The platelet aggregation induced by ristocetin or botrocetin was also inhibited by the IgG. These results indicate that this inhibitor may recognize the binding region of vWF to GPIb. Therefore, the antibody to vWF appears to represent the likely pathophysiological mechanism responsible for the acquired vWD in this patient.
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PMID:Acquired von Willebrand disease associated with multiple myeloma; characterization of an inhibitor to von Willebrand factor. 757 99

To get insights into the pathogenesis of acquired von Willebrand disease associated with plasma cell dyscrasias, we searched for the expression of the physiological von Willebrand factor receptor, the GpIb/GpIX complex, on bone marrow plasma cells. The monoclonal spike in our patient corresponded to IgG kappa molecules; there was no plasma inhibitor to vWF:Ag or vWF:RiCoF. The bone marrow contained 1-2% plasma cells. Fresh bone marrow cells or plasma cells enriched bone marrow cells after a 48 h in vitro culture in the presence of interleukin 6 were stained by an immuno alkaline phosphatase technique using monoclonal antibodies (mAb) to von Willebrand factor, GpIb alpha and beta chain, GpIIb/IIIa and Gp IX. Two different mAb to GpIb alpha chains reacted with the majority (75%) of plasma cells whereas all other reagents yielded no staining. Malignant plasma cells from patients with multiple myeloma without haemostatic disorder were unreactive with anti-GpIb mAb. These data suggest that in some patients with acquired von Willebrand syndrome there is a GpIb mediated selective adsorption of von Willebrand factor on clonal plasma cells.
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PMID:Expression of GpIb on plasma cells in a patient with monoclonal IgG and acquired von Willebrand disease. 821 99

The role of mixed hematopoietic chimerism in engraftment and relapse after allogeneic BMT remains unclear. To better evaluate post-transplant chimerism we used polymerase chain reaction (PCR) in vitro amplification of four single locus simple repetitive DNA sequences, all of which vary extensively in their repeat number among different individuals: variable number of tandem repeats D1S80, APOB and D17S5, and the tetranucleotide repeat F8VWF. We tested 13 cases of CML, four of multiple myeloma (MM), three of ANLL and one of B-CLL. In a sequential analysis protocol with the different loci, the donor could be distinguished from the recipient in 14 of 20 (70%) pairs with the first marker used (D1S80). When a donor of opposite sex was involved, karyotyping and Y chromosome-specific PCR were also used. With the use of the four markers, chimerism was identified in all the pairs. Mixed chimerism was present in 5 patients, and complete chimerism in 15. No patients relapsed. The application of PCR for documenting post-transplant chimerism has several advantages over Southern blotting: increased sensitivity, use of small amounts of sample, ease of preparation of DNA, elimination of restriction enzyme analysis and of radioisotopes, and speed.
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PMID:In vitro amplification of hypervariable DNA regions for the evaluation of chimerism after allogeneic BMT. 840 55


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