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Biomedical subjects

D V Devine

Publications and source records attributed to D V Devine.

69 records · Page 4Linked to original sources
PubMed1987

Evidence for the involvement of platelet glycoproteins other than GP Ib in heparin-associated thrombocytopenia and thrombosis.

Heparin-associated thrombocytopenia and thrombosis (HATT) is a potentially fatal complication of heparin therapy which is characterized by a progressive fall in the platelet count associated with arterial or venous thrombosis. The etiology is consistent with the development an antibody which, in the presence of heparin, induces intravascular platelet aggregation. Biochemical analysis has demonstrated that the platelet membrane glycoprotein (GP) Ib binds heparin. Recent studies have shown that polyclonal antisera or monoclonal antibodies to GP Ib can inhibit platelet aggregation induced by HATT plasma in the presence of heparin implicating GP Ib as the site of heparin-antibody interaction. The Bernard-Soulier syndrome (BSS) is an inherited bleeding disorder in which the platelets fail to adhere to exposed subendothelium due to a deficiency of GP Ib. We have used the platelets from a patient with documented BSS to further investigate the role of GP Ib in the heparin- dependent platelet aggregation induced by the plasma of three patients with HATT. We have shown that platelet aggregation by HATT plasma in the presence of heparin occurred as readily with BSS platelets as with normal donor platelets. These results indicate that glycoprotein Ib cannot be the only site of platelet-heparin-antibody interactions.

Bernard-Soulier Syndrome↗
PubMed1987

Regulation of the activity of platelet-bound C3 convertase of the alternative pathway of complement by platelet factor H.

The alternative pathway of complement is regulated on the surface of homologous blood cells at the C3 amplification step by the membrane protein decay-accelerating factor, as well as by the plasma protein factor H. We have reported elsewhere that platelets from patients with paroxysmal nocturnal hemoglobinuria regulate the activity of the C3 convertase C3bBb, even though they lack decay-accelerating factor. We now report that normal human platelets contain factor H, which was released from the platelet in response to complement deposition or thrombin stimulation. Factor H was localized to the platelet alpha granules by immunocytochemical techniques. As determined by a solid-phase radioimmunoassay, thrombin-stimulated platelets released approximately equal to 54 ng of factor H per 10(8) platelets. The release of factor H in response to complement or thrombin was inhibited by treating the platelets with metabolic inhibitors. Such inhibition resulted in a 3-fold increase in the activity of C3bBb. Platelets that released factor H bound only half as many molecules of radiolabeled factor B to platelet-bound C3b than platelets that could not release factor H. Treatment of platelets with anti-decay-accelerating factor antibody had no effect on the activity of C3bBb unless the release of factor H was blocked. Therefore, so far as we know, human platelets have a unique mechanism for the regulation of the alternative pathway of complement.

Complement Activating Enzymes↗
PubMed1987

Measurement of plasma fibrin D-dimer levels with the use of a monoclonal antibody coupled to latex beads.

Recently, monoclonal antibody (DD-3B6) to fibrin D-dimer was prepared and coupled to latex beads to provide a specific test (Dimertest) for fibrinolysis. The purpose of this study was to evaluate the Dimertest assay as a clinical laboratory test for the measurement of plasma fibrin D-dimer derivatives. The Dimer-test assay specifically detected 2 micrograms/mL of purified fibrin D-dimer or fibrin D-dimer/fragment E complex added to afibrinogenemic plasma but did not detect 500 micrograms/mL of either fibrinogen fragments X, D, E, or 160 micrograms/mL cross-linked fibrinogen. The fibrin(ogen) degradation product (FDP) assays of American Dade or Wellcome Diagnostics detected 5.0 micrograms/mL of fibrin D-dimer and from 1 to 10 micrograms/mL of the other FDPs. Twenty-eight percent of 150 random plasma samples assayed from hospitalized patients were positive for fibrin D-dimer derivatives. Plasma samples from 152 patients suspected of having disseminated intravascular coagulation (DIC) were assayed for serum FDP (Wellcome Diagnostics) and plasma fibrin D-dimer derivatives. Samples from 69% of patients with serum FDP levels less than 10 micrograms/mL, and more than 90% of those with serum FDP levels greater than 10 micrograms/mL, were positive for fibrin D-dimer derivatives. Dimertest results were not modified by heparin, streptokinase, freeze-thawing, or clotting plasma. Serum fibrinogen-related antigens were immunoadsorbed from Dimer-test positive sera by anti-fibrinogen antibody and formalin-fixed Cowan I strain Staphylococcus aureus. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and protein blotting with the use of monoclonal antibody DD-3B6 demonstrated a protein band with similar mobility to purified D-dimer. The measurement of plasma fibrin D-dimer derivatives by the Dimertest assay is a rapid, sensitive, and specific laboratory test for fibrinolysis. The Dimertest assay has proven to be a useful addition to the clinical laboratory and should be helpful in the diagnosis and management of patients with diseases associated with fibrinolysis.

Antibodies, Monoclonal↗
PubMed1987

Interactions of the platelets in paroxysmal nocturnal hemoglobinuria with complement. Relationship to defects in the regulation of complement and to platelet survival in vivo.

The blood cells of patients with paroxysmal nocturnal hemoglobinuria (PNH) have abnormal interactions with complement. The activity of the alternative pathway C3 convertase on the platelets of 9 out of 19 patients with PNH was elevated. 10 patients had C3 convertase activity within the normal range even though 80-95% of their platelets lacked the complement regulatory protein decay accelerating factor (DAF) that is absent from the affected blood cells in PNH. PNH and normal platelets released factor H when C3 was bound to their surfaces. This may account for the apparent regulation of C3 convertase activity on platelets that lack DAF. The abnormal uptake of the membrane attack complex of complement by PNH III erythrocytes was not seen in PNH platelets. 111Indium-labeled platelet survival times were normal in five of eight patients, which suggests that the lack of the membrane attack complex defect results in normal platelet survival in PNH.

Blood Coagulation Factors↗
PubMed1987

Acute myeloblastic leukemia in paroxysmal nocturnal hemoglobinuria. Evidence of evolution from the abnormal paroxysmal nocturnal hemoglobinuria clone.

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hematopoietic stem cell disorder in which the blood cells demonstrate aberrant interactions with serum complement. In part, this is due to the absence of the complement regulatory protein, decay accelerating factor (DAF). A small number of patients with PNH have gone on to develop acute nonlymphocytic leukemia, which is thought to arise from the injured marrow as a second hematopoietic disorder. We have studied a patient with PNH who developed acute myeloblastic leukemia (AML); the blasts from this patient were found to lack DAF as measured by polyclonal antibody binding and fluorescence flow cytometry as well as by immunoblotting. The blasts from 11 other patients with AML bound anti-DAF antibody in amounts similar to normal mononuclear cells from healthy donors. Cells of the human leukemia cell lines HL-60, K562, U937, and HEL also bound anti-DAF antibody. In addition to DAF deficiency, blasts from the PNH patient had undetectable alkaline phosphatase activity, in contrast to human leukemia cell lines. These data suggest that the leukemic cells of the PNH patient arose out of the PNH clone and that AML in the setting of PNH is not a separate disorder.

CD55 Antigens↗
PubMed1987

Pseudo-Bernard-Soulier syndrome: thrombocytopenia caused by autoantibody to platelet glycoprotein Ib.

The Bernard-Soulier syndrome is an inherited bleeding disorder that is due to a deficiency in platelet glycoprotein Ib. Bernard-Soulier platelets fail to agglutinate in response to ristocetin despite normal levels of factor VIII:von Willebrand factor. We report a patient who developed severe refractory thrombocytopenia postsurgically while receiving procainamide therapy. Thrombocytopenia was immune mediated since the patient's platelets bore high levels of antiplatelet antibody. Radioimmunoprecipitation studies demonstrated that the autoantibodies had specificity for platelet glycoproteins Ib and V as well as platelet HLA. The patient's plasma as well as purified immunoglobulin G completely inhibited the ristocetin-induced aggregation of normal platelets but did not inhibit adenosine diphosphate-induced aggregation. The laboratory studies revealed that this patient suffered from antibody-mediated thrombocytopenia with unusual characteristics that we have called pseudo-Bernard-Soulier syndrome.

Aged↗
PubMed1986

Restriction of the alternative pathway of human complement by intact Trypanosoma brucei subsp. gambiense.

We studied the interaction of African trypanosomes with human complement. Bloodstream forms of Trypanosoma brucei subsp. gambiense isolated from mice activated the alternative pathway of complement during a 30-min incubation in vitro. In human serum, all cells remained intact and motile during this period. C3 was detected on the surface by a direct binding assay with a monoclonal antibody which recognizes C3b and iC3b. C3 deposition could also be detected by this radioimmunoassay when parasites were incubated with purified C3. Such C3 binding was enhanced by factor B, factor D, and magnesium. Surface deposition of factor B was demonstrated both by flow immunofluorescence analysis and binding of radiolabeled factor B. C3 binding and factor B binding were inhibitable by EDTA but not by ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N' -tetraacetic acid (EGTA). The inhibited binding could be restored by addition of magnesium. No human immunoglobulin G or mouse immunoglobulin was detected on the trypanosome surface. By flow cytometry, neither human C5 nor polymerized C9 was detected on trypanosomes incubated in serum, although this assay was able to detect C5 and C9 on the surface of complement-treated human erythrocytes. Using a radioimmunoassay which measures C5b-9 in serum, we found that there was no generation of SC5b-9 in serum which had been incubated with trypanosomes. We concluded that, although trypanosomes activate the alternative pathway of complement, they are not lysed, because the cascade does not continue beyond the establishment of C3 convertase.

Animals↗
PubMed1986

Structural and functional differences between decay-accelerating factor and red cell acetylcholinesterase.

The abnormal erythrocytes in paroxysmal nocturnal hemoglobinuria, both PNH II (the moderately abnormal cells) and PNH III (the markedly abnormal cells), lack both acetylcholinesterase (AChE) activity and decay-accelerating factor (DAF) activity. Both of these activities are found on glycoprotein molecules with a molecular weight of about 70 Kd. To demonstrate that these two activities are in fact on different proteins, we have shown that binding to normal red cells of antibody to DAF does not inhibit the subsequent binding of monoclonal antibody to AChE nor AChE activity. Inhibition of DAF activity by polyclonal antibody increases the susceptibility of normal erythrocytes to lysis by complement but inhibition of AChE activity by antibody does not. The rate of decay of the C3 convertase complex of the classical pathway of complement activation was inhibited by DAF added in the fluid phase but not by AChE. When DAF was exhaustively immunoprecipitated from a solution of the erythrocyte membrane proteins, AChE remained and vice versa. These studies indicate that acetylcholinesterase and decay-accelerating factor are two different proteins, both of which are lacking on PNH II and PNH III erythrocytes.

Acetylcholinesterase↗
PubMed1986

Fragment D-dimer levels: an objective marker of vaso-occlusive crisis and other complications of sickle cell disease.

Although abnormalities in coagulation tests have been reported during vaso-occlusive crises in patients with sickle cell disease, objective, readily performed laboratory tests that document the occurrence of this complication have not been available. We examined the relationship between fibrin D-dimer levels and the occurrence of complications in patients with sickle cell disease, using a commercially available latex bead agglutination assay. The patients were either asymptomatic, hospitalized for vaso-occlusive crisis, or had other complications of sickle cell disease including leg ulcers, chronic cholecystitis, aseptic necrosis, joint pain and infection. Fifty-seven percent of 187 samples on 96 patients had elevated levels of fibrin D-dimer. Ninety percent of 75 samples from asymptomatic patients were negative for fibrin D-dimer (less than 1 microgram/ml) but 97% of 29 samples from patients with vaso-occlusive crisis and 85% of 83 samples from patients with other complications of sickle cell disease were positive. In serial studies, worsening or amelioration in clinical complications were reflected in increasing or decreasing levels of fibrin D-dimer, respectively. The molecular species of fibrin identified by the latex agglutination test was shown to be fragment D-dimer by successive immunoprecipitation and protein blot analysis. We conclude that the complications of sickle cell disease, including vaso-occlusive crisis, result in the production of fibrin D-dimer, and its detection may be used as a marker for the presence of the complication.

Anemia, Sickle Cell↗
PubMed1984

Reactions of immunoglobulin G-binding ligands with platelets and platelet-associated immunoglobulin G.

Immunoglobulin G (IgG) bound to platelets is usually detected by one of two general methods: binding of labeled anti-IgG or consumption of anti-IgG. The latter method gives, in general, values 5-10-fold greater than the former under the same conditions. To investigate these discrepancies, we have compared the detection of platelet-bound IgG by a labeled anti-IgG binding assay and by a quantitative antiglobulin consumption test using the same antibodies. The interaction of 125I-labeled monoclonal anti-IgG or polyclonal anti-IgG with washed and IgG-coated platelets was studied. The binding of these ligands to washed normal platelets was largely (50-80%) nonspecific; the binding was not saturable and was only partially inhibitable by excess unlabeled anti-IgG. The binding of anti-IgG to platelets coated with anti-PIA1, a platelet-specific IgG antibody, appeared to be saturable and inhibitable; the dissociation constant (KD) of this IgG-anti-IgG reaction was 4.9 X 10(-9) for monoclonal and 1.4 X 10(-7) for polyclonal anti-IgG. The ratio of sites present on the membrane (determined by 131I-labeled anti-PIA1) to the number of binding sites for anti-IgG determined by Scatchard analysis was 0.53 for monoclonal anti-IgG and 1.3 for polyclonal anti-IgG. The binding of monoclonal anti-IgG to platelet-bound immune complexes or IgG aggregates appeared to be complex. 131I-Labeled IgG was affixed to platelets and was detected by three tests: direct binding of radiolabeled monoclonal anti-IgG and quantitative antiglobulin consumption (QAC) tests, which were quantitated either by measuring directly the amount of radiolabeled anti-IgG consumed from fluid phase (direct QAC), or indirectly by reference to a calibration curve relating the consumption of anti-IgG by known amounts of fluid-phase, non-immune IgG (indirect QAC). The amount of platelet-bound IgG detected by the direct binding of 125I-labeled monoclonal anti-IgG and by the direct QAC approximated that known to be bound to the platelet. The results of the indirect QAC test were 10-fold greater. The discrepancy appears to be due to the fact that there is a difference between the IgG-anti-IgG interaction when IgG is bound to a platelet and when it is in solution or bound to plastic nonspecifically or specifically. This difference results in a falsely high value for platelet-bound IgG when fluid-phase or plastic-bound IgG is used to calibrate the antiglobulin consumption test.

Animals↗
PubMed1984

Identification of platelet proteins that bind alloantibodies and autoantibodies.

We have used the techniques of radioimmunoprecipitation (RIP) and Western blot to identify the membrane proteins that bind certain alloantibodies. Anti-PlA1 sera precipitated two bands, corresponding to platelet glycoproteins IIb and III, whether or not calcium was present during the procedure. By Western blot, this antibody bound only glycoprotein III. Anti-PlA1 serum does not precipitate proteins from the platelets of a patient with Glanzmann's thrombasthenia. Two monoclonal antibodies reacting with lymphocyte HLA antigens, as well as sera from highly allosensitized patients, precipitated bands of 38,500 and 13,500 daltons. These bands correspond to the molecular weights of the two subunits of the HLA antigen, as it has been described for other cell types. The patients' sera also precipitated a protein of 72,000 daltons from some platelets. The sera of two patients with quinidine-induced thrombocytopenia precipitated a 138,000-dalton band (glycoprotein Ib-alpha) in the presence of quinidine. The purified IgG antibody from one patient did not require other plasma factors to bind to platelets in the presence of quinidine, while purified antibody from a second patient required plasma factors other than, or in addition to von Willebrand factor. Although several sera from patients with idiopathic thrombocytopenic purpura (ITP) were tested, only one precipitated membrane proteins by the RIP method; this serum identified binding proteins corresponding to glycoproteins IIb and III.

Antibodies, Monoclonal↗
PubMedDate not supplied

Rapid fibrin D-dimer tests for deep venous thrombosis: factors affecting diagnostic utility.

Measurement of fibrin D-dimer may be a useful diagnostic test to exclude a diagnosis of deep venous thrombosis (DVT) in the emergency department setting. However, the specific assay format may influence its sensitivity and ultimate clinical utility. We tested samples from 200 patients under evaluation for DVT using three fibrin D-dimer assays: the SimpliRED whole blood agglutination assay, a latex agglutination assay, and the Dimertest EIA. Latex agglutination assays were performed in both a specialized laboratory and a routine laboratory. The negative predictive value for all tests was > 90%. The sensitivity of the SimpliRED assay was similar to that of the latex assay. The sensitivity of the latex assay was significantly lower when performed by generalist laboratory technologists. Thus, while D-dimer may be a useful test for the exclusion of DVT, subjective endpoint latex agglutination assays should be performed only by appropriately trained personnel.

Adolescent↗
PubMedDate not supplied

Angiotensin-converting enzyme (ACE) alleles in the Quechua, a high altitude South American native population.

Recently it was reported that an allelic variant of the gene encoding angiotensin-converting enzyme (ACE) was significantly over-represented in a cohort of elite British mountaineers. It was proposed that this may be evidence for a specific genetic factor influencing the human capacity for physical performance. The implication that this allele could enhance performance at high altitude prompted us to determine its frequency in Quechua speaking natives living at altitudes greater than 3000m on the Andean Altiplano in South America. We found that the frequency of the putative performance allele in the Quechuas, although significantly higher than in Caucasians, was not different from lowland Native American populations. This observation suggests that, although the higher frequency of the 'performance allele' may have facilitated the migration of the ancestral Quechua to the highlands, the ACE insertion allele has not been subsequently selected for in this high altitude population.

Alleles↗
PubMedDate not supplied

Atypical perinuclear antineutrophil cytoplasmic antibodies after colectomy in inflammatory bowel disease.

A typical perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) have been detected in most patients with ulcerative colitis and primary sclerosing cholangitis. Persistent atypical p-ANCA have been observed in ulcerative colitis patients with a prior proctocolectomy, especially with pouchitis, suggesting that this serological marker might be predictive of subsequent development of chronic or refractory pouchitis. This study prospectively evaluated this serological marker in 24 consecutive patients with inflammatory bowel disease and prior colectomies (12 with a clinical diagnosis of ulcerative colitis and 12 with a clinical diagnosis of Crohn's disease involving the colon). Of these, 14 were positive, including 11 with extensive ulcerative colitis and three with Crohn's disease. Although two of three ulcerative colitis patients with pouchitis were positive, eight of eight ulcerative colitis patients having a pelvic pouch with no] pouchitis were also positive, as was a patient who elected to have an end-ileostomy (Brooke's ileostomy). Two patients had abnormal liver chemistry tests. Both had end-stage primary sclerosing cholangitis treated with liver transplantation and were positive for this serological marker. Although atypical p-ANCA may be a marker of persistent inflammation in pelvic pouch patients, a positive test result should not be used for prognosis or as a decision-making parameter for pelvic pouch procedures.

Adolescent↗