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

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.
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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

Pneumocystis carinii pneumonia occurred in 6 of 17 rhesus monkeys infected with simian immunodeficiency virus and was studied by immunohistochemistry and by scanning and transmission electron microscopy. A monoclonal antibody/streptavidin-biotin-peroxidase staining method was highly sensitive for detecting the organisms in small, early lesions and was much more sensitive and specific than traditional silver impregnation methods. Reprocessing of paraffin wax-embedded lung tissue for scanning electron microscopy and use of a video printer to produce a photographic montage of light microscopic lesions allowed the same areas of tissue to be examined and compared by both methods. The ultrastructural morphology of P. carinii in the rhesus monkey was identical to that in man, as were the histological and electron microscopic lesions, including pulmonary fibrosis. Trophozoites were seen attached to alveolar type I epithelium mainly by intimate apposition to the plasma membrane, but scanning electron microscopy also showed attachment by elongated filopodia. Few macrophages were present in infected alveoli, and though phagocytosis followed by digestion of P. carinii trophozoites was observed, it appeared to occur at a very low level.
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PMID:Pneumocystis carinii pneumonia in simian immunodeficiency virus infection: immunohistological and scanning and transmission electron microscopical studies. 207 17

The human serum antibody response to polypeptides of human immunodeficiency virus type 1 (HIV-1) was quantitated by reflectance densitometry of Western immunoblots by using two commercially available blotting systems. In one system, human antibodies were detected by an avidin-biotin method using peroxidase as the label, and in the other, human antibodies were detected by peroxidase-labeled conjugate against human immunoglobulins. When staining intensity was plotted against the log of the serum dilution, a shallow slope was evident, with a 50% change in staining intensity requiring as much as a 100-fold change in antibody content. The linear range of the staining intensity curves was frequently found in serum dilutions of 1:2,500 to 1:1,000,000, and a plateau was often observed at high antibody concentrations (1:80 to 1:640). When replicate strips were tested, staining intensities varied by +/- 7 to 37%. Antibodies to p24gag and gp160env were readily detectable in several sera diluted 1:1,000,000, a result seen with both blotting systems. If Western blotting were to be used to observe increase or decreases in levels of antibodies to various polypeptides, several widely spaced serum dilutions would need to be tested.
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PMID:Quantitation of antibody reactivity to human immunodeficiency virus (type 1) proteins and glycoproteins on Western immunoblots by reflectance densitometry. 212 85

In horseradish peroxidase (EC: 1.11.1.7)-dependent immunoblot assays, particulate 3,3',5,5'-tetramethylbenzidine (TMB) is shown to be a more efficient immunoblot substrate than the standard substrate 3,3'-diaminobenzidine (DAB), because TMB is easily prepared, stable, and less carcinogenic than is DAB. Assays of antibody in a serially diluted human immunodeficiency virus (HIV) control serum (CDC reference CAT# VS2151) have the same sensitivity limits with both DAB and TMB (1:312,500). Complete, working substrate solutions of H2O2/TMB/enhancer and of H2O2/DAB were stored at room temperatures and at 48 degrees C respectively. Periodic tests showed the TMB substrate system to be functional after four weeks at 48 degrees C and after eight weeks at room temperature, while the DAB system was functional after one week at 48 degrees C and after four weeks at room temperature. The stability, safety, and convenience of the commercially available TMB kits make this substrate ideal for immunoblot tests.
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PMID:Comparison of particulate 3,3',5,5'-tetramethylbenzidine and 3,3'-diaminobenzidine as chromogenic substrates for immunoblot. 232 54

Nitrocellulose was activated with divinyl sulfone, a spacer of ethylenediamine, and glutaraldehyde. The aldehyde groups on the activated nitrocellulose, Nit-CHO, were stable through one month at 4 degrees C. Peptides were attached to the membrane by reaction of the amino group with the free carbonyl, forming peptide bonds. The decapeptide angiotensin I (AI), the octapeptide angiotensin II (AII), angiotensin analogues, Met- and Leu-enkephalin (Met-E and Leu-E) were tested on the membranes with specific rabbit antibodies (sRaAb) against the peptides, and visualized by horseradish peroxidase conjugated anti-rabbit antibody (HRP-anti-RaAb). With this technique AII could be detected with a sensitivity of 20 pg/cm2 and AI by 500 pg/cm2. Substitution of Ala7 for Pro7 in AI and AII caused a marked reduced binding of anti-AI and antid-AII antisera, respectively, and it completely abolished crossreactivity of anti-AI with Ala7-AII as well as anti-AII with Ala7-AI. Peptides from the gp41 and gp36 antigens corresponding to the sequence aa596-618 of the human immunodeficiency viruses type 1 and 2, HIV-1 and HIV-2, were tested on Nit-CHO with two human sera from infected patients. The serological reactions were specific for both the HIV-1 and HIV-2 peptide, respectively. This indicated that the technique could be exploited for serological testing of humans. Separation of peptides by high performance thin layer chromatography (HPTLC) and identification by immunoblotting was demonstrated with angiotensin analogues. After separation by HPTLC on silica aluminium plates the peptides were electrotransfered by semidry electroblotting on Nit-CHO, followed by specific antibody overlays and developed as for the dot immunobinding technique. This combined method enabled us to differentiate between closely related peptide analogues and it improved the sensitivity of peptide detection 100-1000 fold as compared to visualization by quenched fluorescence on chromatography plates.
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PMID:Dot immunobinding and immunoblotting of picogram and nanogram quantities of small peptides on activated nitrocellulose. 239 30

A case of prepubertal periodontitis was observed and examined immunohistologically with peroxidase-antiperoxidase staining. The patient was an 11-year and 7-month-old Japanese girl, well-developed and well-nourished. Her parents were first cousins. Her chief complaint was the loosening and loss of the permanent teeth. There was a similar history of primary dentition. Her remaining permanent teeth were loosened with severe alveolar bone loss, but calculus deposit was minimal. Significantly, there was no palmar-plantar hyperkeratosis. General examination showed normal data except for the increase of the immunoglobulin concentrations. In neutrophil function tests chemotaxis was depressed, although phagocytosis, random migration and superoxide production were within normal limits. Histologically, neutrophils were seen in the gingival tissue and other findings were also similar to those of adult periodontitis. In immunohistological examination, IgG-bearing cells which mostly consisted of plasma cells predominated in the lesion. Considering the past history, the immunodeficiency and the absence of palmar-plantar hyperkeratosis, the case was diagnosed as prepubertal periodontitis.
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PMID:Immunohistological study with peroxidase-antiperoxidase staining in a case of generalized prepubertal periodontitis. 242 Sep 57

Cells infected with human immunodeficiency virus (HIV) were selectively stained with peroxidase-coupled antibodies in a recently developed plaque assay for HIV. The numbers of plaques formed with the human T-cell lymphotropic virus type III strain of HIV were exactly the same in stained (immunologically detectable) and unstained (visible) dishes. However, four times more plaques were visualized in stained dishes than in unstained dishes when the YU-6 and acquired immune deficiency syndrome-associated retrovirus strains of HIV were used. Linear relationship was observed between the number of stained plaques and the virus concentrations in the titration of human T-cell lymphotropic virus type III and YU-6. The assay should be useful for the titration of HIV, especially for non- or weakly cytopathic strains of HIV.
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PMID:Plaque staining assay for non- or weakly cytotoxic human immunodeficiency virus. 244 Sep 7

The polymerase chain reaction (PCR) procedure has many potential applications in mass screening. We describe here a general assay for colorimetric detection of amplified DNA. The target DNA is first amplified by PCR, and then a second set of oligonucleotides, nested between the first two, is incorporated by three or more PCR cycles. These oligonucleotides bear ligands: for example, one can be biotinylated and the other can contain a site for a double-stranded DNA-binding protein. After linkage to an immobilized affinity reagent (such as a cloned DNA-binding protein, which we describe here) and labeling with a second affinity reagent (for example, avidin) linked to horseradish peroxidase, reaction with a chromogenic substrate allows detection of the amplified DNA. This amplified DNA assay (ADA) is rapid, is readily applicable to mass screening, and uses routine equipment. We show here that it can be used to detect human immunodeficiency virus sequences specifically against a background of human DNA.
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PMID:Colorimetric detection of specific DNA segments amplified by polymerase chain reactions. 264 2

In the capture competition immunoassay, undiluted serum was reacted in solution with purified human immunodeficiency virus (HIV) antigen in wells of microtest plates coated with anti-HIV immunoglobulin G antibodies (HIV capture antibodies). HIV antibodies present in the serum being tested combined with the HIV antigen and thus blocked (completely or partially) the fixation of the antigen to the capture layer. Unblocked antigenic activity was measured in subsequent steps by the use of biotinylated anti-HIV immunoglobulin G and peroxidase-conjugated avidin. The assay was evaluated in comparison with indirect enzyme-linked immunosorbent assay and Western (immuno-) blot (WB). A total of 180 serum samples which reacted repeatedly as positive in indirect enzyme-linked immunosorbent assay but negative in WB were found to be negative by the capture competition assay. Of 54 serum samples showing dubious reactions (single p24 bands in WB), 53 were clearly separated into positive or negative reactions, whereas 1 serum sample gave a borderline reaction. It was concluded that a characteristic feature of this kind of inhibition assay is a very low frequency of equivocal results.
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PMID:Antigen-antibody reaction in solution in capture competition immunoassay for human immunodeficiency virus antibodies. 276 47

A luminescence assay was adapted for detection of peroxidase-labelled secondary antibodies, which react specifically with antibodies to human immunodeficiency virus on Western blots. This method is about one hundred times more sensitive than either commercial enzyme-linked immunosorbent assay or the chromogenic peroxidase assay on Western blots and detects seroconversion earlier than any other technique currently available.
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PMID:A luminescence Western blot with enhanced sensitivity for antibodies to human immunodeficiency virus. 303 9


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