Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thrombocytopenia as a complicating event in human immunodeficiency infection is a rather common hematological disorder and in many aspects resembles idiopathic(immune) thrombocytopenic purpura (ITP). Consequently, treatment of severe cases is similar to treating ITP, but steroids should be administered with particular caution in patients suffering from AIDS. Alternatives to steroids are considered in the present article with emphasis on intravenous immunoglobulin as a means to favourably influence the pathogenic events on the platelet surface.
 ...
PMID:Review on therapeutic options in HIV associated thrombocytopenia with emphasis on i.v. immunoglobulin treatment. 186 40

We have studied the conditions of in vitro binding of platelet glycoprotein IIb/IIIa (GPIIb/IIIa) to fibrinogen and applied the results to identify and measure the serum inhibitors to the binding. For the enzyme-linked immunosorbent assay, platelet extract was delivered to a fibrinogen-coated microtiter plate that was incubated for 2 hours, followed by incubation with anti-GPIIb/IIIa monoclonal antibody for another 2 hours. The plate was then incubated with peroxidase-conjugated anti-mouse IgG for color development. The binding was shown to be calcium-dependent. The binding was partially blocked by treating the coated fibrinogen with anti-fibrinogen antibody. Reduction or dissociation of GPIIb/IIIa resulted in the total loss of its ability to bind to fibrinogen. Platelet extracts of patients with hemophilia showed decreased binding (25% and 14%, compared with control platelet extract), and an extract from a patient with Glanzmann's thrombasthenia showed no binding. With the enzyme-linked immunosorbent assay we have measured serum inhibitors to GPIIb/IIIa binding to fibrinogen in 35 hemophilia A, 17 immune thrombocytopenic purpura, 22 human immunodeficiency virus-related immune thrombocytopenic purpura, and 29 systemic lupus erythematosus serum samples. In those patients with inhibition by serum, polyethylene glycol precipitation of circulating immune complexes (CICs) decreased the inhibition by the supernatants, and all the resolubilized CIC precipitates demonstrated inhibition, which indicates that CICs play a major role in the inhibition of GPIIb/IIIa binding to fibrinogen. This, then, provides evidence of CIC-mediated impaired GPIIb/IIIa binding to fibrinogen in hemophilia A, HIV-ITP, and SLE.
 ...
PMID:Inhibition of platelet GPIIb/IIIa binding to fibrinogen by serum factors: studies of circulating immune complexes and platelet antibodies in patients with hemophilia, immune thrombocytopenic purpura, human immunodeficiency virus-related immune thrombocytopenic purpura, and systemic lupus erythematosus. 200 77

In 4 years (1984-1987), 183 bone marrow examinations were performed on 155 human immunodeficiency virus (HIV) antibody positive patients. One hundred and fifty three had category IV AIDS. One-third of the marrows yielded specific information. This included opportunistic infection, in particular Mycobacterium Avium Intracellulare Complex (MAI) (24%), malignancy (4%), consistent with ITP (9%) and iron deficiency (1%). In the remaining two thirds of the bone marrows the most frequent non-specific abnormalities were dyserythropoiesis, erythroid hypoplasia, reticuloendothelial iron block, granulomas, lymphoid aggregates, plasmacytosis and histiocytosis. Common peripheral blood findings were anemia, lymphopenia, anisocytosis, rouleaux and atypical lymphocytes. Peripheral blood and bone marrow examinations on 16 patients on AZT are included. These patients have more pronounced blood and bone marrow abnormalities. The causes of these abnormalities are multifactorial and include low T4 levels, severe viral and other infections and therapy with marrow toxic drugs.
 ...
PMID:Peripheral blood and bone marrow findings in patients with acquired immune deficiency syndrome. 209 Oct 4

Between February 1983 and April 1986 we studied peripheral blood and bone marrow samples from 20 patients with human immunodeficiency virus (HIV) related disease. 14 patients had AIDS, three had ARC, two had PGL and one had ITP as a sole manifestation of HIV related disease. Peripheral blood abnormalities included marked anisocytosis and poikilocytosis, rouleaux formation, neutropenia, lymphopenia, monocytopenia, a left shift in the granulocyte series and, in the patients with AIDS, vacuolated monocytes. The most frequent bone marrow abnormalities were reticuloendothelial iron block, dyserythropoiesis, megaloblastic change and erythroid hypoplasia. Excess histiocytes were noted in four marrows, one exhibiting haemophagocytosis. None of the bone marrows showed lymphopenia. Eight of the 20 marrows were difficult or impossible to aspirate. None of the trephine biopsies showed increased reticulin. The causes of these abnormalities are probably multiple and include opportunistic infections, drug therapy, immune mechanisms and possibly direct insult by the HIV virus.
 ...
PMID:Peripheral blood and bone marrow abnormalities in patients with HIV related disease. 356 82

Human immunodeficiency virus 1-related idiopathic thrombocytopenic purpura (HIV-1-ITP) patients have a 4-fold increased percentage of CD5+ B cells and a 4.8-fold increased percentage of serum immune complexes precipitated by polyethylene glycol (PEG-ICs) compared to control subjects, as reported previously. Since CD5+ B cells produce predominantly IgM rheumatoid factor (RF) vs. Fc of IgG and PEG-ICs contain high levels of IgM, we looked for the presence of RF in the immune complexes of HIV-1-ITP patients. PEG-ICs were adsorbed to protein A and dissociated with acid, and IgM and IgG were purified by gel filtration and affinity chromatography. Solid-phase ELISA was used to measure antibody specificity vs. platelets, Fc, and HIV-1 gp120, p24, and CD4. Dissociated IgG antibody reacted with platelets, HIV-1 gp120, p24, and CD4, but not with Fc. Serum IgG did not react with platelets or Fc but did react with HIV-1 gp120, p24, and CD4. Both PEG-IC IgM and serum IgM reacted with Fc as well as the other four antigens. Control IgM and IgG were unreactive. Isolated IgM from PEG-ICs relocated approximately 50% of the IgG preincubated with IgM to the Vo region of a G200 gel-filtration column. Anti-platelet IgG but not IgM could be affinity-purified from fixed platelets. Both F(ab')2 fragments of anti-platelet IgG and the total PEG-IC bound to platelets in a saturation-dependent manner. F(ab')2 of anti-platelet IgG inhibited 50% binding of PEG-IC to platelets at an F(ab')2/complex ratio of 3:1 (wt/wt). Scatchard analysis revealed two classes of binding sites: high-affinity Kd values of 0.8-1.8 nM and lower-affinity Kd values of 6.6-12.3 nM with respective numbers of binding sites of 44,000-57,000 and 122,000-256,000 (n = 4). Anti-platelet IgG of 6/6 patients precipitated GPIIIa from platelet lysates of surface 125I-labeled platelets. Platelet count correlated inversely with anti-platelet IgG (r = -0.73; P < 0.01; n = 27). Thus, PEG-ICs of HIV-1-ITP patients contain IgM RF, which sequesters serum anti-platelet IgG containing anti-GPIIIa. Anti-platelet IgG contributes to binding of immune complexes to platelets and correlates with thrombocytopenia.
 ...
PMID:Sequestration of anti-platelet GPIIIa antibody in rheumatoid factor immune complexes of human immunodeficiency virus 1 thrombocytopenic patients. 789 59

Selective tropism of human immunodeficiency virus (HIV) for cells with CD4 receptors and especially for TH lymphocytes--key cells in hematopoiesis--has from the clinico-biologic point of view a great many hematologic manifestations of which knowledge is essential for a good diagnosis and treatment as well as for a judicious estimation of prognosis. Thus the study presents the hematologic entities specifically associated with HIV infection (such as ITP, NHML) as well as the hematologic entities associated with HIV infection without presenting a causal relationship with the latter. The study also discusses the quantitative and morphologic changes of peripheral blood and of bone marrow often enlightening for the disease and its complications. An important chapter in the study is devoted to the hematologic changes induced by the HIV infection therapy as well as by the manners of therapeutic approach to the complex hematologic problems raised by the disease.
 ...
PMID:Hematologic manifestations of infection with the human immunodeficiency virus. 792 Mar 33

Patients with human immunodeficiency virus-type 1-immune thrombocytopenic purpura (HIV-1-ITP) have elevated polyethylene glycol (PEG)-precipitable immune complexes (ICs) composed of IgG, IgM, and complement that are threefold to sevenfold higher than in healthy control subjects. These complexes contain anti-F (ab')2 as well as anti-idiotype antibodies versus anti-HIV-1gp120. Because anti-F (ab')2 and anti-idiotype antibodies correlate with thrombocytopenia (r = .83 [J Clin Invest 77:1756, 1986] and r = .90 [J Clin Invest 89:356, 1992], respectively) we studied the binding of ICs to platelets and monocytes as well as their role in platelet-monocyte rosette formation. ICs bind to platelets in a saturation-dependent manner (optimum at 10 micrograms/mL; 0.5% of serum conc). Binding to platelets could not be inhibited with platelet saturating concentrations of aggregated IgG or with monoclonal antibody (MoAb) IV.3 versus FcR gamma II. Platelet binding could be inhibited with Fab anti-C3, anti-Clq, or anti-C4 by 57%, 40%, and 46% respectively, not with control Fab (P < .001). Monocytes from HIV-1-ITP patients form rosettes with normal platelets 16.8 +/- 5.2 rosettes/100 monocytes compared with 4.8 +/- 0.8 control monocytes plus normal platelets (P = .009). Gel-washed HIV-1-ITP platelets formed 19 +/- 2.0 rosettes with U937 cells compared to 6.3 +/- 1.0 for normal platelets (P = 0.001). Arming of U937 cells with HIV-1-ITP ICs (5 micrograms/mL) formed 36.7 +/- 2.5 rosettes compared with 10.6 +/- 1.2 for control ICs (P < .01). Rosetting of armed U937 cells could be inhibited with MoAbs versus the alpha chains of CD11a (LFA-1), 11b (Mac-1), or 11c (p150,95) by 67%, 70%, and 61%, respectively (P < .007), whereas binding of ICs to U937 cells was unaffected. Isotype-matched control as well as MoAbs versus antigens on U937 cells (CD13, CD33) or the anti-FcR gamma II receptor had no effect. However, Fab fragments of polyclonal anti-C3 inhibited rosette formation by 78% (P < .01); control Fab had no effect. Thus, platelet-monocyte rosette formation is not Fc dependent. It is complement receptor dependent and requires the cooperation of all three leuCAM integrins.
 ...
PMID:Role of leuCAM integrins and complement in platelet-monocyte rosette formation induced by immune complexes of human immunodeficiency virus-type 1-immune thrombocytopenic purpura patients. 848 17

Our objective was to examine the efficacy and toxicity of continuous, low-dose interferon-alpha therapy for human immunodeficiency virus-related immune thrombocytopenic purpura (HIV-ITP) in a Phase II clinical trial overseen by a community-based consortium of physicians conducting clinical trials in HIV-related diseases. Sixteen patients with HIV-ITP defined by prospective clinical criteria were enrolled; the majority had failed other therapies for HIV-ITP. Baseline and serial measurements were made of platelet counts, complete blood counts, serum chemistries, platelet-associated immunoglobulin, and CD4+ T-lymphocyte counts; subjective symptoms and bleeding were recorded. Three million units of interferon-alpha 2b were self-administered by subcutaneous injection every Monday, Wednesday, and Friday for 16 weeks. Thirteen participants were evaluable for response. One obtained a complete response, eight had partial responses, and four had no response to interferon-alpha therapy. The mean absolute platelet count of the group rose from 15.5 x 10(9)/L at baseline to 47.3 x 10(9)/L at 2 weeks and remained in this range for the duration of the study. CD4+ T-lymphocyte counts and serum chemistries did not change significantly during therapy. Ability to detect platelet-associated immunoglobulin did not change in a predictable manner in relation to platelet count response. Hematologic toxicity was limited to one episode of granulocytopenia, which resolved after a lowering of zidovudine dosage. Subjective toxicities were mild and tolerable, and minor bleeding problems improved in all participants so affected. Low-dose, continuous therapy with interferon-alpha resulted in meaningful increases in the platelet counts of the majority of study participants with HIV-ITP. Interferon-alpha was safe and tolerable for most participants with HIV-ITP at the dosage and schedule employed in this study. Interferon-alpha for clinically significant thrombocytopenia and who have failed to respond to zidovudine.
 ...
PMID:Continuous low-dose interferon-alpha therapy for HIV-related immune thrombocytopenic purpura. 854 45

We report the results of intravenous anti-D (WinRho, WinRho SD) therapy in 261 non-splenectomized patients treated at the New York Hospital-Cornell Medical Center over the period from 1987 to 1994. Children (n = 124) and adult patients (n = 137) with classic immune thrombocytopenic purpura (ITP; n = 156) or human immunodeficiency virus (HIV) related thrombocytopenia (n = 105) and acute (n = 75) or chronic (n = 186) disease at the time of the initial anti-D treatment were studied. In addition, 11 previously splenectomized patients were treated as a separate group. Our objectives were to evaluate the following. (1) Efficacy of anti-D: The response after the initial infusion was analyzed according to clinical parameters, such as patient's age, HIV status, gender, disease duration, pretreatment platelet count, and hemoglobin value, as well as treatment-related factors, including the dose of anti-D, the solvent detergent treatment of the preparation, and the type of administration. (2) Use of anti-D as maintenance therapy: The duration of response after the initial infusion and the results of subsequent treatments were evaluated. (3) Safety/toxicity of anti-D: Postinfusion reactions and hemoglobin decrease after treatment were studied. Anti-D is a safe treatment providing a hemostatic platelet increase in greater than 70% of the Rh+ non-splenectomized patients. The group with the best results is HIV- children, but all patient groups respond and the effect lasts more than 21 days in 50% of the responders. Duration of response is not influenced by HIV status; furthermore, HIV+ patients show no adverse effects on hemoglobin decrease or HIV disease progression. Patients with chronic ITP after splenectomy have minimal or no response to intravenous anti-D.
 ...
PMID:Intravenous anti-D treatment of immune thrombocytopenic purpura: experience in 272 patients. 910 86

Nondenaturing gel electrophoresis was used to study the nucleotide substrate-induced conformational change in reverse transcriptase (RT) of human immunodeficiency virus type 1 (HIV-1). Dead-end complex was formed between HIV-1 RT, dideoxynucleotide chain-terminated primer, and DNA template in the presence of deoxynucleotide triphosphate (dNTP) complementary to the next position on the template. Complexes which form in the absence of the next complementary dNTP were disrupted by adding excess poly(rA)/oligo(dT) or heparin just prior to electrophoresis. Dead-end complex formation by noncomplementary dNTP's or ribonucleotides was at least 2000-fold less efficient than with the complementary nucleotide. When dA was the next nucleotide on the template, analogues of dTTP supported dead-end complex formation with increased apparent Kd (dTTP < dideoxy-TTP approximately alpha-thio-dTTP < dUTP < 3'-azidothymidine triphosphate). A similar relationship was observed for dGTP analogues across from dC on the template (dGTP < dideoxy-GTP < alpha-thio-dGTP << dITP < dideoxy-ITP). The optimal length of the primer/template duplex region for dead-end complex formation was between 20 and 32 base pairs. Primer-template with a mismatched primer terminus did not support dead-end complex formation, and primer terminated with 3'-azidothymidine formed dead-end complex with 25-fold elevated apparent Kd. By contrast, dead-end complex formation on primer terminated with dideoxy-IMP base paired with dC on the template was more efficient than on primer terminated with dideoxy-GMP. Implications for the mechanisms of discrimination between nucleotide analogues by HIV-1 RT are discussed.
 ...
PMID:Nucleotide-induced stable complex formation by HIV-1 reverse transcriptase. 915 15


1 2 3 Next >>