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)

Shikonin is a major component of zicao (purple gromwell, the dried root of Lithospermum erythrorhizon), a Chinese herbal medicine with various biological activities, including inhibition of human immunodeficiency virus (HIV) type 1 (HIV-1). G protein-coupled chemokine receptors are used by HIV-1 as coreceptors to enter the host cells. In this study, we assessed the effects of shikonin on chemokine receptor function and HIV-1 replication. The results showed that, at nanomolar concentrations, shikonin inhibited monocyte chemotaxis and calcium flux in response to a variety of CC chemokines (CCL2 [monocyte chemoattractant protein 1], CCL3 [macrophage inflammatory protein 1alpha], and CCL5 [regulated upon activation, normal T-cell expressed and secreted protein]), the CXC chemokine (CXCL12 [stromal cell-derived factor 1alpha]), and classic chemoattractants (formylmethionyl-leucine-phenylalanine and complement fraction C5a). Shikonin down-regulated surface expression of CCR5, a primary HIV-1 coreceptor, on macrophages to a greater degree than the other receptors (CCR1, CCR2, CXCR4, and the formyl peptide receptor) did. CCR5 mRNA expression was also down-regulated by the compound. Additionally, shikonin inhibited the replication of a multidrug-resistant strain and pediatric clinical isolates of HIV in human peripheral blood mononuclear cells, with 50% inhibitory concentrations (IC(50)s) ranging from 96 to 366 nM. Shikonin also effectively inhibited the replication of the HIV Ba-L isolate in monocytes/macrophages, with an IC(50) of 470 nM. Our results suggest that the anti-HIV and anti-inflammatory activities of shikonin may be related to its interference with chemokine receptor expression and function. Therefore, shikonin, as a naturally occurring, low-molecular-weight pan-chemokine receptor inhibitor, constitutes a basis for the development of novel anti-HIV therapeutic agents.
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PMID:Shikonin, a component of chinese herbal medicine, inhibits chemokine receptor function and suppresses human immunodeficiency virus type 1. 1293 78

Entry of human immunodeficiency type 1 virus (HIV-1) into target cells requires both CD(4)and one of the chemokine receptors. Viruses predominantly use one, or occasionally both, of the major co-receptors CCR5 and CXCR4, although other receptors, including CCR2B and CCR3, function as minor co-receptors. A 32-nucleotide deletion (D32) within the b-chemokine receptor 5 gene (CCR5) has been described in subjects who remain uninfected despite extensive exposition to HIV-1. The heterozygous genotype delays disease progression. This allele is common among Caucasians, but has not been found in people of African or Asian ancestry. A more common transition involving a valine to isoleucine switch in transmembrane domain I of CCR2B (64I), with unknown functional consequences, was found to delay disease progression but not to reduce infection risk. As the Brazilian population consists of a mixture of several ethnic groups, we decided to examine the genotype frequency of these polymorphisms in this country. There were 11.5% CCR5 heterozygotes among the HIV-1 infected population and 12.5% among uninfected individuals, similar to data from North America and Western Europe. The prevalence of CCR2-64I homozygotes and heterozygotes was 0.06 and 15.2%, respectively, also similar to what is known for North America and Western Europe.
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PMID:Frequency of polymorphisms of genes coding for HIV-1 co-receptors CCR5 and CCR2 in a Brazilian population. 1453 83

The role that host genetics plays in the modification of the rate of human immunodeficiency virus 1 (HIV-1)-related disease progression was evaluated in a seroprevalent cohort of 1049 children with symptomatic HIV-1 infection who participated in 2 clinical trials in the United States. Variants including CCR2-V64I, CCR5-wt/Delta32, CCR5-59029-G/A, CCR5-59353-T/C, CCR5-59356-C/T, and SDF1-3'-G/A were identified by polymerase chain-reaction genotyping. Children with the CCR5-wt/Delta32 genotype experienced significantly delayed disease progression, including less neurocognitive impairment. In the CCR5-wt/wt group, the most rapid disease progression was in those with the CCR5-59029-A/A genotype, which was present in 23% of the children. Although the SDF1-3'-A/A variant was associated with more-rapid disease progression, it occurred in <2% of the children studied. Modest or little impact was associated with the CCR5-59353, CCR5-59356, or CCR2 genotypes. Thus, in children with the CCR5-wt/wt genotype, variants at CCR5-59029 have the broadest impact on disease progression. These data suggest that, in children, host genetics plays an important role in HIV-1-related disease progression and neurological impairment.
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PMID:Genetic influence of CCR5, CCR2, and SDF1 variants on human immunodeficiency virus 1 (HIV-1)-related disease progression and neurological impairment, in children with symptomatic HIV-1 infection. 1462 71

Genetic polymorphisms of CCR5, CCR2, and SDF1 genes have been associated with resistance during human immunodeficiency virus type 1 (HIV-1) infection and disease progression. In the present report, we studied the frequency and co-occurrence of CCR5Delta32, CCR5-59029A/G, CCR2-64I, and SDF1-3'A allelic variants among HIV-1-seronegative individuals (n = 171) in Moscow. Observed allelic frequencies were 0.0906 [95% confidence interval (CI), 0.06-0.1212] for CCR5Delta32, 0.4072 (95% CI, 0.3542-0.4602) for CCR5-59029G, 0.1061 (95% CI, 0.0728-0.1394) for CCR2-64I, and 0.2218 (95% CI 0.1715-0.2721) for SDF1-3'A. A significant linkage disequilibrium (p = 0.0034) between CCR2-64I and SDF1-3'A alleles was observed.
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PMID:Prevalence of alleles associated with HIV resistance in Russia. 1514 Mar 77

Virus infection of the central nervous system (CNS) often results in chemokine upregulation. Although often associated with lymphocyte recruitment, increased chemokine expression is also associated with non-lymphocyte-mediated CNS disease. In these instances, the effect of chemokine upregulation on neurological disease is unclear. In vitro, several chemokines including monocyte chemotactic protein 1 (MCP-1) protect neurons from apoptosis. Therefore, in vivo, chemokine upregulation may be a protective host response to CNS damage. Alternatively, chemokines may contribute to pathogenesis by stimulating intrinsic brain cells or recruiting macrophages to the brain. To investigate these possibilities, we studied a neurovirulent retrovirus, Fr98, that induces severe non-lymphocyte-mediated neurological disease and causes the upregulation of several chemokines that bind to chemokine receptors CCR2 and CCR5. Knockout mice deficient in CCR2 had reduced susceptibility to Fr98 pathogenesis, with significantly fewer mice developing clinical disease than did wild-type controls. In contrast, no reduction in Fr98-induced disease was observed in CCR5 knockout mice. Thus, signaling through CCR2, but not CCR5, plays an important role in Fr98-mediated pathogenesis. Three ligands for CCR2 (MCP-1, MCP-3, and MCP-5) were upregulated during Fr98 infection of the brain. Antibody-blocking experiments demonstrated that MCP-1 was important for retrovirus-induced neurological disease. In situ hybridization analysis revealed that MCP-1 was expressed by glial fibrillary acidic protein-positive astrocytes. Thus, astrocytes, previously not thought to play an effector role in the disease process were found to contribute to pathogenesis through the production of MCP-1. This study also demonstrates that chemokines can mediate pathogenesis in the CNS in the absence of lymphocytic infiltrate and gives credence to the hypothesis that chemokine upregulation is a mechanism by which retroviruses such as human immunodeficiency virus induce neurological damage.
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PMID:MCP-1 and CCR2 contribute to non-lymphocyte-mediated brain disease induced by Fr98 polytropic retrovirus infection in mice: role for astrocytes in retroviral neuropathogenesis. 1516 38

To investigate African long-term survivors (LTSs) infected with non-subtype B human immunodeficiency virus type 1 (HIV-1), we obtained full-length HIV-1 RNA sequences and immunogenetic profiles from 6 untreated women enrolled in the Pumwani Sex Worker Cohort in Nairobi, Kenya. There were no discernible sequence changes likely to cause attenuation. CCR2-V64I, an immunogenetic polymorphism linked to LTSs, was detected in 4 women, all of whom carried the HLA B58 allele. Further investigation of 99 HIV-1-infected Nairobi women found an association between CCR2-V64I and HLA B58 (P=.0048). Studying the interaction among immunogenetics, immune responses, and viral sequences from all HIV-1 subtypes may increase our understanding of slow HIV-1 disease progression.
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PMID:Long-term survivors in Nairobi: complete HIV-1 RNA sequences and immunogenetic associations. 1527 96

To determine the influence of host genetics on human immunodeficiency virus (HIV) type 1 infection, we examined 94 repeatedly exposed seronegative (ES) individuals for polymorphisms in multiple genes and compared the results with those for 316 HIV-1-seropositive and 425 HIV-1-seronegative individuals. The frequency of homozygous C-C chemokine receptor (CCR) 5- Delta 32 was higher in ES (3.2%) than in HIV-1-seropositive individuals (0.0%; P=.012). However, the CCR5-59029A, CCR2-64I, stromal cell-derived factor (SDF)-1-3'A, RANTES (regulated on activation, normally T cell-expressed and -secreted)-403A, and RANTES-28G polymorphisms were not associated with resistance to HIV-1 infection. Furthermore, we identified novel variants in the DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin) repeat region and observed that heterozygous DC-SIGN reduced the risk of HIV-1 infection (3.2% in ES individuals vs. 0.0% in HIV-1-seropositive individuals; P=.011).
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PMID:Analysis of genetic polymorphisms in CCR5, CCR2, stromal cell-derived factor-1, RANTES, and dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin in seronegative individuals repeatedly exposed to HIV-1. 1531 53

Both antiretroviral therapy and the human coreceptor polymorphism CCR2-V64I slow progression of human immunodeficiency virus type 1 (HIV-1) disease. To examine the effect of V64I on disease progression in patients receiving therapy, we determined CCR2 genotypes in the Women's Interagency HIV Study cohort. We studied 2047 HIV-1-infected women, most of whom initiated treatment during the study. No association was seen between CCR2 genotype and either disease progression or therapeutic response, suggesting that the benefits of treatment most likely overshadow the salutary effects of the V64I polymorphism.
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PMID:CCR2 genotype and disease progression in a treated population of HIV type 1-infected women. 1547 20

Here we report that the N-pyridinylmethyl cyclam analog AMD3451 has antiviral activity against a wide variety of R5, R5/X4, and X4 strains of human immunodeficiency virus type 1 (HIV-1) and HIV-2 (50% inhibitory concentration [IC(50)] ranging from 1.2 to 26.5 microM) in various T-cell lines, CCR5- or CXCR4-transfected cells, peripheral blood mononuclear cells (PBMCs), and monocytes/macrophages. AMD3451 also inhibited R5, R5/X4, and X4 HIV-1 primary clinical isolates in PBMCs (IC(50), 1.8 to 7.3 microM). A PCR-based viral entry assay revealed that AMD3451 blocks R5 and X4 HIV-1 infection at the virus entry stage. AMD3451 dose-dependently inhibited the intracellular Ca(2+) signaling induced by the CXCR4 ligand CXCL12 in T-lymphocytic cells and in CXCR4-transfected cells, as well as the Ca(2+) flux induced by the CCR5 ligands CCL5, CCL3, and CCL4 in CCR5-transfected cells. The compound did not interfere with chemokine-induced Ca(2+) signaling through CCR1, CCR2, CCR3, CCR4, CCR6, CCR9, or CXCR3 and did not induce intracellular Ca(2+) signaling by itself at concentrations up to 400 microM. In freshly isolated monocytes, AMD3451 inhibited the Ca(2+) flux induced by CXCL12 and CCL4 but not that induced by CCL2, CCL3, CCL5, and CCL7. The CXCL12- and CCL3-induced chemotaxis was also dose-dependently inhibited by AMD3451. Furthermore, AMD3451 inhibited CXCL12- and CCL3L1-induced endocytosis in CXCR4- and CCR5-transfected cells. AMD3451, in contrast to the specific CXCR4 antagonist AMD3100, did not inhibit but enhanced the binding of several anti-CXCR4 monoclonal antibodies (such as clone 12G5) at the cell surface, pointing to a different interaction with CXCR4. AMD3451 is the first low-molecular-weight anti-HIV agent with selective HIV coreceptor, CCR5 and CXCR4, interaction.
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PMID:Inhibition of human immunodeficiency virus replication by a dual CCR5/CXCR4 antagonist. 1554 51

To dissect the haplotype structure of candidate genes for disease association studies, it is important to understand the nature of genetic variation at these loci in different populations. We present a survey of haplotype structure and linkage disequilibrium of chemokine and chemokine receptor genes in 11 geographically-distinct population samples (n=728). Chemokine proteins are involved in intercellular signalling and the immune response. These molecules are important modulators of human immunodeficiency virus (HIV)-1 infection and the progression of the acquired immune deficiency syndrome, tumour development and the metastatic process of cancer. To study the extent of genetic variation in this gene family, single nucleotide polymorphisms (SNPs) from 13 chemokine and chemokine receptor genes were genotyped using the 5' nuclease assay (TaqMan). SNP haplotypes, estimated from unphased genotypes using the Expectation-Maximization-algorithm, are described in a cluster of four CC-chemokine receptor genes (CCR3, CCR2, CCR5 and CCRL2) on chromosome 3p21, and a cluster of three CC-chemokine genes [MPIF-1 (CCL23), PARC (CCL18) and MIP-1alpha (CCL3)] on chromosome 17q11-12. The 32 base pair (bp) deletion in exon 4 of CCR5 was also included in the haplotype analysis of 3p21. A total of 87.5 per cent of the variation of 14 biallelic loci scattered over 150 kilobases of 3p21 is explained by 11 haplotypes which have a frequency of at least 1 per cent in the total sample. An analysis of haplotype blocks in this region indicates recombination between CCR2 and CCR5, although long-range pairwise linkage disequilibrium across the region appears to remain intact on two common haplotypes. A reduced-median network demonstrates a clear relationship between 3p21 haplotypes, rooted by the putative ancestral haplotype determined by direct sequencing of four primate species. Analysis of six SNPs on 17q11-12 indicates that 97.5 per cent of the variation is explained by 15 haplotypes, representing at least 1 per cent of the total sample. Additionally, a possible signature of selection at a non-synonymous coding SNP (M106V) in the MPIF-1 (CCL23) gene warrants further study. We anticipate that the results of this study of chemokine and chemokine receptor variation will be applicable to more extensive surveys of long-range haplotype structure in these gene regions and to association studies of HIV-1 disease and cancer.
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PMID:Haplotype structure and linkage disequilibrium in chemokine and chemokine receptor genes. 1558 86


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