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J V Jordan

Publications and source records attributed to J V Jordan.

8 recordsLinked to original sources
PubMed1987

Binding of quinine- and quinidine-dependent drug antibodies to platelets is mediated by the Fab domain of the immunoglobulin G and is not Fc dependent.

The antibody domain controlling reactions between platelet membranes and drug-dependent (dd) antibodies from patients with thrombocytopenia induced by cinchona alkaloids was studied using F(ab')2, Fab, and Fc fragments made from purified dd-IgG. By direct binding radioimmunoassay (RIA) measurements, 20,000 to 50,000 antibody molecules bound per platelet equivalent of purified platelet membranes at apparent saturation with three different antibodies. F(ab')2 and Fab fragments bound to platelet membranes drug dependently but Fc fragments did not. The ability of dd-IgG fragments to compete with intact IgG was quantitatively measured by RIA and by complement fixation. F(ab')2 and Fab competed with intact IgG at an 8:1 and greater than 50:1 molar ratio, respectively, in RIA, and at a 1.6-3:1 and 44-75:1 ratio, respectively, by complement fixation assays. Fc did not compete with IgG in either assay. We conclude that the Fab domain supports attachment of dd antibody to the platelet surface.

Autoantibodies↗
PubMed1986

Evaluation by quantitative acid elution and radioimmunoassay of multiple classes of immunoglobulins and serum albumin associated with platelets in idiopathic thrombocytopenic purpura.

Immunoglobulins (Igs) and serum albumin were eluted from normal platelets and platelets from patients with idiopathic thrombocytopenic purpura (ITP) with a quantitative acid elution procedure followed by solid-phase radioimmunoassay (SPRIA). Acid elution was shown to release a reproducible fraction of platelet-associated Igs, and the amounts released per platelet were independent of the platelet concentration over a wide range of concentrations. This procedure is suitable for sensitive, reproducible, and specific quantitation of large numbers of samples. Washed platelets from 13 normal donors contained the following components (expressed in femtograms per platelet, mean +/- 2 SEM): IgG, 1.40 +/- 0.26; IgA, 0.72 +/- 0.36; IgM 0.078 +/- 0.036; albumin 7.7 +/- 1.5. Immunoglobulins and albumin eluted from the platelets of ten ITP patients (two in remission), expressed as femtograms per platelet, mean (range), were: IgG 104 (0.3 to 750); IgA 90 (0.9 to 715); IgM 162 (1.2 to 1,300); and albumin 34 (6.8 to 199). All platelet-associated Igs from thrombocytopenic ITP patients were found to be elevated twofold to 2,300-fold with one Ig class occasionally elevated 50-fold to 100-fold higher than the others. A similar group of ten thrombocytopenic ITP patients was found to have twofold to 26-fold elevations of platelet-associated albumin. This demonstration of increases in multiple classes of Igs as well as serum albumin associated with platelets from ITP patients suggests that some nonimmune process may be contributing to the phenomenon of increased platelet-associated proteins in ITP.

Blood Platelets↗
PubMed1985

Transient Passovoy defect during a febrile illness.

The Passovoy defect is a recently characterized hemorrhagic diathesis. We describe a patient with a febrile illness, possibly from Epstein-Barr (EB) virus, who acquired this defect transiently. Prothrombin time; assays for factors VIII, IX, XI, XII; and Fletcher (prekallikrein) and Fitzgerald (high molecular weight kininogen) factors were normal. No definite circulating inhibitor could be demonstrated. The transient Passovoy defect could possibly be ascribed to the infectious process or sulfisoxazole, which the patient had received.

Adult↗
PubMed1985

Red cell fragmentation syndrome with the use of subclavian hemodialysis catheters.

The red cell fragmentation syndrome can occur due to abnormalities of the heart or the blood vessels or vascular malformations. We describe three patients who developed symptomatic hemolytic anemia due to red cell fragmentation with the use of single-lumen subclavian hemodialysis catheters. Retrospective analysis of 75 other patients who had undergone dialysis through this catheter disclosed five additional cases. Red cell fragmentation appears to be associated with partial catheter occlusion by thrombus or development of a clot at the catheter tip or both. The fragmentation resolved in all cases on withdrawal of the catheter. All patients with this catheter should be closely monitored for the red cell fragmentation syndrome, and the catheter should be withdrawn if it develops. White cell fragmentation was also seen in one patient.

Adult↗