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)

Conventional assays based on infection of T-cell lymphoblastoid lines with tissue culture-adapted strains of human immunodeficiency virus (HIV) are well established and have been used successfully to discover potent inhibitors of HIV replication. In this report we show that such assays are not easily applied to testing the susceptibilities of clinical HIV isolates to inhibitors because of differences in replication rates and cytotoxicity, thus demonstrating that conventional HIV assays should be used with caution when the zidovudine susceptibility of clinical isolates is assessed. An assay based on plaque reduction in CD4+ HeLa cell monolayers was validated by determining susceptibilities of HIV to a large number of inhibitors in this system. In general, 50% inhibitory doses for HIV type 1 and 2 strains derived from plaque reduction data were in good agreement with susceptibility data obtained by using conventional assays with T-cell lines. The susceptibilities of previously identified zidovudine-resistant HIV isolates to a large group of inhibitors, including nonucleosides, such as interferons and soluble CD4, were tested by using a plaque reduction assay in CD4+ HeLa cells. Surprisingly, an extremely narrow range of cross resistance was observed; cross resistance was limited to nucleoside analogs containing a 3'-azido group. These data point the way to the use of combinations of inhibitors to delay the appearance of drug resistance.
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PMID:Susceptibilities of zidovudine-susceptible and -resistant human immunodeficiency virus isolates to antiviral agents determined by using a quantitative plaque reduction assay. 233 56

We present a case of chronic mucocutaneous candidiasis of the chronic diffuse kind. It began at eight months of age with lesions in plaque in the totality of the oral and nasal mucosa with affection of the nails. He received different treatment during ten years, without improvements. The diagnosis was established by clinical features en laboratory exams as follows: Skin test to Candida antigen and PPD antigen, direct smears, immunoglobulins and leucocyte random migration test. He received treatment with ketoconazole at an initial dose of 100 mg daily, and it was increased to 200 mg each day for a two years period, and then 100 mg every other day for an other year. Simultaneously, a Candida antigen stimulus treatment was used. We stress about the possibility of an immune enhancing role for ketoconazole as well as about that the correction of secondary immunodeficiency due to the chronic antigen stimulus.
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PMID:[Chronic mucocutaneous candidiasis. A case report]. 236 5

Although atypical gingivitis may be an early indicator of human immunodeficiency virus (HIV) infection, dental caries and periodontal disease has not been investigated in African HIV patients. To correct this gap in the research, the prevalence of dental caries, gingival inflammation, and oral hygiene was measured in 83 male and female acquired immunodeficiency syndrome (AIDS) patients hospitalized in Kinshasa, Zaire, in 1988-89. Most patients were 21-40 years of age; the mean age was 39 years. 32% of these patients has decayed teeth, teeth were missing in 35%, and 5% had fillings. According to the Plaque Index, 69% of the AIDS patients had good oral hygiene. On the other hand, 66% (76% of females and 54% of males) has gingival inflammation, and it was considered severe in 30% of these cases. The only variable that was significantly higher among AIDS patients than healthy individuals in Kinshasa was gingivitis. The high incidence of gingivitis in AIDS patients is most likely a reflection of an impaired immune system and the susceptibility to opportunistic infections. Oral candidiasis was isolated from subgingival plaque in 94% of the cases in this series, suggesting a need for more attention to the role of Candida in the pathogenesis of HIV-related periodontal disease.
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PMID:Prevalence of dental caries, gingivitis, and oral hygiene in hospitalized AIDS cases in Kinshasa, Zaire. 240 61

Sera were collected from patients with common varied immunodeficiency (CVI) prior to and following intravenous gamma-globulin (IVGG) infusion. Cultures of pokeweed mitogen (PWM)-stimulated peripheral blood mononuclear cells from normal donors in medium containing post-IVGG infusion sera generated significantly fewer plaque-forming cells (PFC) than those cultures in medium containing the corresponding pre-IVGG infusion sera. However, preinfusion CVI sera were found to be similar to normal sera in their capacities to support PWM-induced PFC generation, despite the disparity in Ig levels between the two groups of sera. Furthermore, serum collected from a CVI patient 24 hr or more after IVGG infusion no longer possessed the same inhibitory capacity as serum collected 10 min after IVGG infusion despite elevated IgG levels compared to baseline. These studies suggest that IVGG infusion may induce an immunosuppressive effect which is transient in nature, raising the possibility of in vivo counterbalancing homeostatic mechanisms responding to this immune perturbation.
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PMID:Modulation of the immune response by immunoglobulin for intravenous use. II. Inhibitory effects of sera from treated patients. 242 97

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 inhibitory effect of all-trans-retinoic acid (RA) on human immunodeficiency virus (HIV) replication upon infection was studied quantitatively using a novel bioassay system with a HTLV-I-carrying human T-cell line, MT-4. The results can be summarized as follows. The appearance of HIV antigen was significantly reduced when the cells were treated with more than 1 microgram/ml of the chemical after infection. When HIV specific plaque assay was performed to titrate the virus from the supernatant of culture treated with 10 micrograms/ml of RA no plaques were observed. When RA was applied directly in the plaque assay, significant decrease of the number of plaques was discerned showing 68, 66, 47 and 16, at doses of 0.1, 1, 5, and 10 micrograms/ml of RA, while 102 plaques were formed in the control dish. The appearance of cytopathic effects of MT-4 cells by HIV was more delayed in RA-treated cultures than in untreated cultures. Concomitant treatment of the cells with 5 micrograms/ml of RA and various concentrations of suramin resulted in the more effective inhibition of HIV replication than suramin alone. RA did not inhibit the reverse transcriptase activity (RT) of HIV directly. These data suggest that RA inhibits HIV replication by inducing an antiviral state in the cells.
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PMID:Effect of retinoic acid on the replication of human immunodeficiency virus in HTLV-I-positive MT-4 cells. 244 Dec 39

Glycyrrhizin sulfate (GLS) was synthesized and investigated for antiviral effect on the human immunodeficiency virus (HIV) in vitro in comparison with the parental anti-HIV compound glycyrrhizin (GL). In MT-4 cells after HIV infection, the virus-induced cytopathic effect and the expression of viral antigens were inhibited by 0.25 mg/ml (0.184 mM) of GLS. Moreover, GLS completely inhibited HIV-induced plaque formation in MT-4 cells at a concentration of 1 mg/ml (736 microM), the 50% inhibitory dose being 0.055 mg/ml (40 microM). GLS was found to be an efficient inhibitor of reverse transcriptase. The effect of GLS was 4 times stronger than that of GL in molar terms.
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PMID:A new anti-human immunodeficiency virus substance, glycyrrhizin sulfate; endowment of glycyrrhizin with reverse transcriptase-inhibitory activity by chemical modification. 244 73

Three boy cousins suffering from x-linked hypogammaglobulinaemia have been described. Their disease is quite different from the classical x-linked hypogammaglobulinaemia. We present data from 15 family members of three families. The three mothers are sisters and 3 boys from 5 are suffering from immunodeficiency. HLA A, B and DR typing and in vitro diagnostics of immune functions of all family members were carried out. In the patients we could demonstrate a well functioning T cell system which seems to be regular for T cell help on PMW driven B cell maturation into cytoplasmic immunoglobulin positive (cIg+) cells of all immunoglobulin classes but we had no evidence for IgG secreting cells in a plaque forming cell (PFC) assay. The registration of spontaneous suppressor phenomena should be taken into account. If patients undergo an gamma-globulin therapy the changed suppressor effects come back to normal values but the secretion defect is unchanged. The three healthy mothers express one identical haplotype (A2 B8 DR3) which we could demonstrate in the three patients but also in one healthy boy.
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PMID:X-linked hypogammaglobulinaemia with a late secretion defect. A family study. 244 12

A new reverse transcriptase (RT) inhibitor was extracted and purified from the red alga Schizymenia pacifica. The chromatographic behavior and chemical properties of this sea algal extract (SAE) suggest that it is a sulfated polysaccharide having a molecular weight of approximately 2,000,000. SAE is composed of galactose (73%), sulfonate (20%), and 3,6-anhydrogalactose (0.65%). SAE is a member of the lambda-carrageenan family, based on its infrared spectrum and products of hydrolysis. SAE selectively inhibited human immunodeficiency virus (HIV) RT and replication in vitro. When MT-4 cells were treated with more than 10(4) inhibitory units (IU) of SAE per ml after HIV infection, significant inhibition of viral antigen synthesis was observed. Furthermore, more than 90% of cells were viable in the cultures exposed to 4 X 10(4) to 8 X 10(4) IU of SAE per ml, while almost all the MT-4 cells in the control culture had died by 10 days after HIV infection. The inhibitory effect of SAE on HIV replication was confirmed by plaque reduction assays. The 50% inhibitory dose of SAE was 9.5 x 10(3) IU/ml. Chondroitin sulfate A, dermatan sulfate, heparan sulfate, keratan polysulfate, and heparin also inhibited the RT of avian myeloblastosis virus. SAE immediately inhibited RT activity when added to an assay mixture after the start of the reaction.
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PMID:Purification and characterization of an avian myeloblastosis and human immunodeficiency virus reverse transcriptase inhibitor, sulfated polysaccharides extracted from sea algae. 244 20

Different isolates (HTLV-IIIB, LAV1 and ARV2) of human immunodeficiency virus (HIV) were cloned by a plaque-forming assay using MT-4 cells. The reverse transcriptase (RT) activity and plaque-forming unit (PFU) titers of all viral preparations were assayed. PFU/RT values, which indicate the relative proportions of incomplete and infectious viruses, were used for determination of viral infectivity. High values were obtained mainly for clones of HTLV-IIIB and LAV1, and low values for ARV2-derived clones, suggesting that ARV2 and its clones were genetically less infectious. For studies on cytocidal effects of the viruses, four clones of HTLV-IIIB, LAV1 and ARV2 were selected that had similar PFU/RT (infectivity) values for proliferation in infected MT-4 cells. When compared at the same dose (MOI), one clone (HTLV-IIIB-C-2) was found to be more cytocidal than the others. Furthermore, plaques induced by HTLV-IIIB-C-2 were larger than those induced by other clones, suggesting that the release of progeny from HTLV-IIIB-C-2-infected cell and their proliferation were the most efficient. Among the cloned viruses tested, three were found to induce strong cytopathic changes (fusion and ballooning) selectively in MT-4 cells. Thus, the infectivity, proliferation and cytopathic fusion-effects were proposed to be encoded by the viral genome and be separable by the plaque-cloning method.
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PMID:Clonal analysis of functional differences among strains of human immunodeficiency virus (HIV). 245 Aug 87


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