Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

CD14(+) interstitial cells reside beneath the epidermis of skin and mucosal tissue and may therefore play an important role in viral infections and the shaping of an antiviral immune response. However, in contrast to dendritic cells (DC) or blood monocytes, these antigen-presenting cells (APC) have not been well studied. We have previously described long-lived CD14(+) cells generated from CD34(+) hematopoietic progenitors, which may represent model cells for interstitial CD14(+) APC. Here, we show that these cells carry DC-SIGN and differentiate into immature DC in the presence of granulocyte-macrophage colony-stimulating factor. We have compared the CD14(+) cells and the DC derived from these cells with respect to dengue virus and human immunodeficiency virus type 1 (HIV-1) infection. Both cell types are permissive to dengue virus infection, but the CD14(+) cells secrete the anti-inflammatory cytokine interleukin 10 and no tumor necrosis factor alpha. Regarding HIV, the CD14(+) cells are permissive to HIV-1, release higher p24 levels than the derived DC, and more efficiently activate HIV Pol-specific CD8(+) memory T cells. The CD14(+) DC precursors infected with either virus retain their DC differentiation potential. The results suggest that interstitial CD14(+) APC may contribute to HIV-1 and dengue virus infection and the shaping of an antiviral immune response.
 ...
PMID:Dendritic cell precursors are permissive to dengue virus and human immunodeficiency virus infection. 1591 83

Previous studies from this laboratory evaluated the role of p68 kinase (PKR) in the control of HIV-1 replication via retrovirus-mediated gene transfer. PKR was studied because it is a key component of the interferon (IFN)-associated innate antiviral defense pathway in mammalian cells. In this study, CD34(+) hematopoietic stem cells (HSC) were transduced with an HIV-1-based lentiviral vector encoding the PKR transgene (pHIV-PIB) and cultured under conditions that support in vitro differentiation. With high-titer pseudotyped vector stocks, the histogram suggests 100% transduction of the HSC because the cells were blasticidin resistant. Analysis of transduced cells by hybridization revealed an average proviral vector copy number of 1.8 and 2.1 copies of vector sequence per cell. Increased PKR expression and activity (phosphorylation of eukaryotic initiation factor 2alpha [eIF2alpha]) were demonstrated in PKR-transduced, differentiated HSC. There was minimal reduction in cell viability and no induction of apoptosis after transduction of PKR. HSC transduced with the pHIV-PIB lentiviral vector demonstrated normal differentiation into CD34-derived T cell progeny. Two days after HIV-1 infection, lentivirus-mediated transduction of PKR inhibited HIV-1 replication by 72% in T cell progeny compared with cells transduced with the empty vector control (pHIV-IB). By days 5 and 7 post-HIV-1 infection, the surviving PKR-transduced cells were protected from HIV-1 infection, as evidenced by a decrease in p24 antigen expression of at least two orders of magnitude. Our results demonstrate that PKR can be effectively delivered to HSC by a lentiviral vector and can protect CD34-derived T cell progeny from HIV-1 infection. These results provide support for application of the innate antiviral defense pathway in a gene therapy setting to the treatment of HIV-1 infection.
 ...
PMID:Lentivirus-mediated transduction of PKR into CD34(+) hematopoietic stem cells inhibits HIV-1 replication in differentiated T cell progeny. 1595 58

Species-specific innate resistance against viral infections offers novel avenues for antiviral therapeutic and prophylactic approaches. The retroviral and lentiviral restriction factors Ref1 and Lv1 are variants of the tripartite motif protein TRIM5alpha, a component of cytoplasmic bodies. TRIM5alpha severely restricts productive retroviral infections at the postentry and preintegration steps by destabilizing the incoming viral capsid via ubiquitination. Using this approach, resistance to HIV-1 infection could be conferred by TRIM5alpha(rh) expression in otherwise susceptible cells. Here we show that stable expression of simian TRIM5alpha(rh) via a lentiviral vector in a permissive cell culture line, Magi-CXCR4, conferred resistance to HIV-1. To translate these findings into a stem cell gene therapy setting, the TRIM5alpha(rh) transgene was stably introduced into CD34(+) hematopoietic progenitor cells to derive transgenic macrophages. Upon viral challenge, TRIM5alpha(rh)-expressing macrophages were highly resistant to HIV-1 infection compared to control cells. Human macrophages expressing TRIM5alpha(rh) were also found to be phenotypically and functionally normal, expressing the characteristic surface markers CD14, CD4, CCR5, CXCR4, MHC II, and B7.1. These results demonstrate that the species-specific restriction factor TRIM5alpha(rh) is effective in conferring HIV-1 resistance in a stem cell setting, thus paving the way for its application in AIDS gene therapy.
 ...
PMID:TRIM5alpharh expression restricts HIV-1 infection in lentiviral vector-transduced CD34+-cell-derived macrophages. 1608 21

We examined the ability of a HIV-1-based vector (VRX494) encoding a 937-bp antisense HIV-1 envelope sequence to inhibit the replication of chimeric SIV/HIV-1 viruses encoding the HIV-1 envelope. Challenge of VRX494-transduced CEMx174 cells resulted in potent inhibition of HIV-1 and several SHIV strains. To evaluate the potential efficacy of the VRX494 vector for stem cell gene therapy, rhesus CD34(+) bone marrow cells were transduced with VRX494 and then cultured on thymus stroma to induce T cell differentiation. Transduction conditions for CD34(+) cells were optimized to yield high transduction efficiency with minimal effective multiplicity of infection. Purified CD4(+) GFP(+) T cells derived from VRX494-transduced CD34(+) cells strongly inhibited SHIV HXBC2P 3.2 and SHIV 89.6P replication compared to controls. Southern blot analysis of VRX494-transduced T cell clones revealed a subset of cells with multiple proviral copies per cell. Expression of GFP and the antisense inhibitor in VRX494-transduced cells was upregulated by Tat. Analysis of HIV-1 envelope sequences in VRX494-transduced cells revealed modifications consistent with those mediated by double-stranded RNA-dependent adenosine deaminase. These results indicate that the macaque/SHIV model should serve as a useful preclinical model to evaluate this lentiviral vector expressing an HIV-1 antisense inhibitor for stem cell gene therapy for AIDS.
 ...
PMID:Inhibition of simian/human immunodeficiency virus replication in CD4+ T cells derived from lentiviral-transduced CD34+ hematopoietic cells. 1616 13

Transduction domains such as those derived from the HIV-TAT protein are candidate vectors for intracellular delivery of therapeutic macromolecules such as DNA and proteins. The mechanism by which they enter cells is controversial, and very little spatial information regarding the downstream fate of these peptides from the plasma membrane is available. We studied endocytic traffic of fluorescent conjugates of HIV-TAT peptide and octaarginine in human hematopoietic cell lines K562 (CD34-) and KG1a (CD34+) and substantiated our findings in epithelia cells. Both peptides were efficiently internalized to endocytic pathways of both hematopoietic cell lines; however, comparative analysis of the intracellular location of the peptides with endocytic probes revealed major differences in spatial organization of their endocytic organelles and their interaction with the peptides at low temperatures. Double labeling confocal microscopy demonstrates that prelabeled lysosomes of all the tested cells are accessible to internalized peptides within 60 min of endocytic uptake. Incubation of cells with nocodazole and cytochalasin D inhibited peptide traffic from early to late endosomal structures, demonstrating a cytoskeletal requirement for lysosomal delivery. Disruption of Golgi and endoplasmic reticulum dynamics was without effect on peptide localization, suggesting that endosomes and lysosomes rather than these organelles are the major acceptor compartments for these molecules.
 ...
PMID:Intracellular traffic and fate of protein transduction domains HIV-1 TAT peptide and octaarginine. Implications for their utilization as drug delivery vectors. 1641 56

Nonintegrating lentiviral (NIL) vectors were produced from HIV-1-based lentiviral vectors by introducing combinations of mutations made to disable the integrase protein itself and to alter the integrase recognition sequences (att) in the viral LTR. NIL vectors with these novel combinations of mutations were used to transduce the human T lymphoid cell line Jurkat and primary human CD34(+) hematopoietic progenitor cells to assess their efficacy measured through transient expression of the enhanced green fluorescent protein (eGFP) reporter gene. The most disabled NIL vectors resulted in initial high levels of eGFP expression (approximately 90% of cells), but expression was transient, diminishing toward background (<0.5%) within less than 1 month. Southern blot analyses of transduced Jurkat cells confirmed the loss of detectable NIL vector sequence (linear form and one- and two-LTR circles) by 1 month. There were low residual levels of integration by NIL vectors (reduced approximately 10(4)-fold compared to wild-type vectors), despite any combination of the engineered changes. Based upon analysis of the sequences of the DNA from the junctions of the vector LTR and cellular chromosomes, these rare integrated NIL vector sequences were not mediated by an integrase-driven mechanism due to reversion of the engineered mutations, but more likely were produced by background recombination events. The development of NIL vectors provides a novel tool for efficient transient gene expression in primary stem cells and hematopoietic and lymphoid cells.
 ...
PMID:Transient gene expression by nonintegrating lentiviral vectors. 1655 11

The effects of CD34 mobilization with chemotherapy and G-CSF administration were evaluated in 13 HIV-positive patients with relapsed lymphomas and low CD4 counts. After mobilization, CD4+ cells increased significantly while HIV-RNA and integrated HIV-DNA showed no increases. G-CSF led to an increase of CD4+ cells with limited effects on HIV replication.
 ...
PMID:Effects on virological and immunological parameters during CD34 mobilization in HIV patients with lymphoma. 1683 24

Lentiviral vectors derived from the human immunodeficiency virus-1 (HIV-1) have a higher propensity to transduce nondividing cells compared to vectors based on oncoretroviruses. We report here that genistein, a previously known protein tyrosine kinase (PTK) inhibitor and G2 cell cycle arrest inducer, significantly enhanced lentiviral transduction in a dose-dependent manner. Increased transduction, as measured by vector expression, was seen in a variety of human cell lines, murine primary lymphocytes, and primary human CD34(+) peripheral blood progenitor cells as well. Increased vector expression was also associated with an increase in vector DNA copy number, as assessed by quantitative PCR. Genistein-mediated G2 cell cycle arrest, rather than PTK inhibition, appears to be the major factor responsible for increased gene transfer. Genistein also increases cyclophilin A (CypA) protein, a cellular protein important for efficient HIV-1 infection. While we show that CypA(-/-) Jurkat cells transduce poorly with lentiviral vectors, genistein does increase gene transfer in CypA-deficient cells. CypA and G2 cell cycle arrest appear to be two independent factors important for efficient lentiviral gene transfer. The role of genistein and other G2-arresting agents may be useful for improving the efficiency of lentiviral gene therapy.
 ...
PMID:G2 cell cycle arrest and cyclophilin A in lentiviral gene transfer. 1690 58

Cord blood, because of its rich mix of fetal and adult hemoglobin, high platelet and WBC counts, and a plasma filled with cytokine and growth factors, as well as its hypo antigenic nature and altered metabolic profile, has all the potential of a real and safe alternative to adult blood transfusion. Our team's experience (from 1st April 1999 to 1st July 2005) with 123 units of placental umbilical cord whole blood (62 ml-154 ml mean 85 ml +/- 8.4 ml SD, median 82 ml, mean packed cell volume 48.8 +/- 4.2 SD, mean percent hemoglobin concentration 16.3 g/dl +/- 1.6 g/dl SD; after collection the blood was immediately preserved in a refrigerator and transfused within 72 hours of collection) collected after lower uterine cesarean section (LUCS), and the transfusion to 16 consenting HIV-positive patients (12 cases had full blown AIDS) with anemia and emaciation is presented here. On the basis of our preliminary experience of cord blood transfusion, we are of the opinion that umbilical cord whole blood transfusion is safe in HIV-positive patients. This blood has the potential to carry more oxygen than adult blood and it does not trigger any clinical, immunological or non-immunological reaction after its transfusion to an adult host with a HIV-positive status. Apart from the correction of anemia, there was also definite improvement in the energy and fatigue levels in individuals with HIV, i.e., physical functioning, a sense of well-being and weight gain from two to five pounds, within three to ten months of the commencement of transfusion. There was also an immediate rise in CD34 levels of peripheral blood in the HLA-randomized host after transfusion, without any clinical graft vs host reaction.
 ...
PMID:A preliminary report of 123 units of placental umbilical cord whole blood transfusion in HIV-positive patients with anemia and emaciation. 1690 52

A 65-year-old diabetic Saudi Arabian man taking glibenclamide for 9 years presented with painful reddish patches and plaques involving the palms and soles of 6 months' duration. These lesions started as small faint purple-red macules and gradually increased in number and size. The patient did not seek any medical advice other than for these painful lesions. His medical history was insignificant. On examination, the patient had multiple, discrete, dull red-to-violaceous and tender patches and plaques of variable sizes on both palms and soles (Figure 1 and Figure 2). His mucous membranes, scalp, and nails were normal. A systemic clinical examination was unremarkable other than an amputation of the distal phalanx of the left index. Result of routine laboratory investigations including complete blood cell count, liver and renal function tests, and chest x-ray were normal. An HIV test was negative. A punch skin biopsy taken from the left palm showed acanthosis and spongiosis in the epidermis. The dermis showed a large number of dilated, medium-sized capillaries with scanty extravasated red blood cells, marked infiltration of lymphocytes and histiocytes, and a few plasma cells (Figure 3 and Figure 4). Immunohistochemistry results were positive for CD34 and CD68. Polymerase chain reaction for human herpesvirus 8 was also positive. The treatment options, including cryotherapy and intralesional chemotherapy, were discussed with the patient but, unfortunately, he did not return for follow-up.
 ...
PMID:Primary palmoplantar Kaposi's sarcoma: an unusual presentation. 1695 40


<< Previous 1 2 3 4 5 6 7 8 9 10