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)

Human parvovirus B19, which infects and lyses erythroid precursors, can cause severe anemia in patients with immunodeficiency. The incidence of parvovirus infection in adult acquired immunodeficiency syndrome (AIDS) patients is unknown. Eighty-one archival formalin-fixed, paraffin-embedded (FFPE) bone marrow biopsies from 73 AIDS adults were immunostained with monoclonal R92F6 against B19 VP1 and VP2 capsid proteins using streptavidin peroxidase and streptavidin alkaline phosphatase techniques. In addition, the same tissues were hybridized in situ with a digoxigenin-labeled parvovirus B19 DNA probe. Five FFPE bone marrows, from 3 HIV-negative patients with positive immunoglobulin M (IgM) serology for parvovirus B19, and 1 parvovirus B19-infected fetal liver were positive controls. By immunoperoxidase, all tissues were negative with R92F6 except the fetal liver, which exhibited strong positivity predominantly in viral inclusions. With immunoalkaline phosphatase, all positive controls were immunoreactive with R92F6; however, the AIDS marrows were negative. With in situ hybridization (ISH), all positive controls and 7 of 81 (8.6%) of AIDS marrows were positive for B19 parvovirus DNA. We conclude that ISH is more sensitive than R92F6 immunohistochemistry in parvovirus B19 detection. A small but significant number of bone marrows from AIDS adults shows evidence of human parvovirus B19 infection.
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PMID:Human parvovirus B19 in bone marrows from adults with acquired immunodeficiency syndrome: a comparative study using in situ hybridization and immunohistochemistry. 922 41

Infections caused by human parvovirus B19 are known to be controlled mainly by neutralizing antibodies. To analyze the immune reaction against parvovirus B19 proteins, four cell lines secreting human immunoglobulin G monoclonal antibodies (MAbs) were generated from two healthy donors and one human immunodeficiency virus type 1-seropositive individual with high serum titers against parvovirus. One MAb is specific for nonstructural protein NS1 (MAb 1424), two MAbs are specific for the unique region of minor capsid protein VP1 (MAbs 1418-1 and 1418-16), and one MAb is directed to major capsid protein VP2 (MAb 860-55D). Two MAbs, 1418-1 and 1418-16, which were generated from the same individual have identity in the cDNA sequences encoding the variable domains, with the exception of four base pairs resulting in only one amino acid change in the light chain. The NS1- and VP1-specific MAbs interact with linear epitopes, whereas the recognized epitope in VP2 is conformational. The MAbs specific for the structural proteins display strong virus-neutralizing activity. The VP1- and VP2-specific MAbs have the capacity to neutralize 50% of infectious parvovirus B19 in vitro at 0.08 and 0.73 microgram/ml, respectively, demonstrating the importance of such antibodies in the clearance of B19 viremia. The NS1-specific MAb mediated weak neutralizing activity and required 47.7 micrograms/ml for 50% neutralization. The human MAbs with potent neutralizing activity could be used for immunotherapy of chronically B19 virus-infected individuals and acutely infected pregnant women. Furthermore, the knowledge gained regarding epitopes which induce strongly neutralizing antibodies may be important for vaccine development.
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PMID:Generation of neutralizing human monoclonal antibodies against parvovirus B19 proteins. 997 77

An immunogenic sequence from the V3 loop of the MN isolate of human immunodeficiency virus type 1 (HIV-1), His-Ile-Gly-Pro-Gly-Arg-Ala-Phe, was transplanted onto a surface loop of the VP2 capsid protein of human rhinovirus 14. To optimize for virus viability and immunogenicity of the transplanted sequence, the HIV sequence was flanked by (1) a cysteine residue that could form a disulfide bond and (2) randomized amino acids (in either of two arrangements) to generate numerous presentations of the Cys-Cys loop. The location for engineering in VP2 was chosen by searching the geometries of disulfide-bound loops in known protein structures. A model for the structure of the transplanted V3 loop sequence was developed using molecular dynamics and energy minimization calculations. Proteolytic digestion with and without reducing agent demonstrated the presence of the disulfide bond in the chimeric virus examined. Monoclonal and polyclonal antibodies directed against the V3 region of the HIV-1MN strain potently neutralized two chimeric viruses. Guinea pig antisera against two chimeric viruses were able to neutralize HIV-1MN and HIV-1ALA-1 in cell culture. The ability of chimeric viruses to elicit antibodies capable of neutralizing the source of the transplanted sequence could be favorable for vaccine development.
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PMID:A disulfide-bound HIV-1 V3 loop sequence on the surface of human rhinovirus 14 induces neutralizing responses against HIV-1. 1022 39

This report describes a real-time reverse transcription polymerase chain reaction (RT-PCR) assay with SYBR Green targeting the VP2 (ORF 3) of feline caliciviruses. All of the 44 feline calicivirus isolates tested were detected, whereas neither feline herpesvirus, feline panleukopenia virus, feline immunodeficiency virus and feline leukemia virus nor other calicivirus like rabbit hemorrhagic disease virus and a canine calicivirus isolate showed specific amplification products. The sensitivity of the SYBR Green reaction was shown to be equivalent to 5 x 10(1) to 5 x 10(2) copies/reaction and the overall sensitivity equivalent to a feline calicivirus titer of 10(0.6) TCID(50)/100 microl in Crandell Reese Feline Kidney (CRFK) cells.
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PMID:Real-time reverse transcription polymerase chain reaction assay to detect a broad range of feline calicivirus isolates. 1626 55

Erythrovirus (parvovirus) B19 (B19) is a common human pathogen. It is a non-enveloped single-strand DNA virus packaging its genome in small tight capsids consisting of viral VP1 and VP2 proteins. It is now accepted that B19 is a relatively quickly evolving virus having diverged in several genetic variants recently identified. The main route of B19 transmission is respiratory, with a majority of infections occurring during childhood and manifesting as erythema infectiousum. B19 can also be transmitted vertically and via blood transfusion and organ transplantation. The majority of adult populations show immunological evidence of previous exposure to B19. Although the immune response is able to clear infection and provide life-long protection against B19, recent data suggest that in some, if not the majority, of individuals the acute phase of infection is followed by viral persistence in the blood or other tissues regardless of the host's immunocompetence. Transmission of B19 by blood and blood products and its resistance to common viral inactivation methods raises several blood safety questions, still unanswered. The diversity of B19 strains and the ability of the virus to persist in the presence of specific antibodies raise the issue of transmissibility by transfusion not so much to immunocompetent recipients but rather to the large proportion of recipients in whom there is some degree of immunodeficiency. The ability of the virus to reactivate in immunodeficient recipients may create difficulties in differentiating between transfusion transmission and reactivation.
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PMID:Human erythrovirus B19 and blood transfusion - an update. 1768 Sep 52

Chicken anemia virus (CAV) is an important pathogen of chicken worldwide, causing severe anemia and immunodeficiency. Its small single-stranded DNA genome (2.3kb) encodes three proteins: VP1, the only structural protein, VP2, a protein phosphatase, and VP3, also known as apoptin, which induces apoptosis. In this study, CAV proteins were expressed in plants as an alternative for recombinant protein production in animal cells. Additionally, the effect of VP3 expression was tested to evaluate possible involvement in programmed cell death in plants. The CAV genes were cloned in binary vectors with the Green fluorescent protein (GFP) as N terminal fusion, and into a Potato virus X (PVX) and Tobacco Mosaic Virus (TMV)-based vectors. Nicotiana benthamiana plants were inoculated with Agrobacterium tumefaciens containing the binary vector constructs or the PVX and TMV constructs. Upon transient expression GFP:VP1 and GFP:VP2 were observed throughout the nucleoplasm, whereas VP3 formed compact aggregates within the nucleus, indicating functional nuclear localization signals in all three proteins. An intense fluorescence was observed for VP2 and VP3 fusions, whereas GFP:VP1 fluorescence remained faint and was only detected in a limited number of cells. Co-expression of GFP:VP1 and VP2 had a marked alteration on the distribution of GFP:VP1, forming large VP1 aggregates throughout the nucleus, indicating an interaction of the two CAV proteins. No visible alteration on GFP pattern was detected upon co-expression of GFP:VP1 and VP3, or with GFP:VP2 and VP3. Plants infected with PVX or TMV-based vectors expressing VP3 displayed strong necrosis and wilting, however, a direct association with VP3 expression and programmed cell death in plants, could not be established. Overall, our results show that all CAV proteins can be expressed in plant cells, though expression level of VP1 needs to be further optimized before testing its potential as (edible) subunit vaccine.
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PMID:Assessing the expression of chicken anemia virus proteins in plants. 1769 36

Chicken anaemia virus (CAV) is a small virus of a unique type with a particle diameter of 23 to 25 nm and a genome consisting of a circular single-stranded (minus-strand) DNA. This DNA multiplies in infected cells via a circular double-stranded replicative intermediate, which was recently cloned. DNA analysis of CAV strains isolated in different continents revealed only minor differences among the various isolates. Apparently, all CAV isolates belong to a single serotype. CAV is not related to other known animal single-stranded circular-DNA viruses, such as porcine circovirus and psittacine beak-and-feather-disease virus. The major transcript from the CAV genome is an unspliced polycistronic mRNA of about 2100 nucleotides encoding three proteins of 51.6 kDa (VP1), 24.0 kDa (VP2) and 13.6 kDa (VP3 or apoptin). All three predicted CAV proteins are synthesized in CAV-infected cells. Immunization with (recombinant) VP1 and VP2 synchronously synthesized in the same cells elicits a protective response and can be used as subunit vaccine against chicken infectious anaemia. CAV causes clinical and subclinical disease in chickens, and is recognized as an important avian pathogen worldwide. In young chickens, CAV causes a transient severe anaemia due to destruction of erythroblastoid cells in the bone marrow and immunodeficiency due to depletion of cortical thymocytes. The depletion of the cortical thymocytes is considered to cause a (transient) immunodeficiency resulting in enhanced concurrent infections and to vaccination failures. The depletion of thymocytes and most likely also of erythroblastoid cells occurs via CAV-induced apoptosis. The CAV-encoded protein apoptin is the main inducer of this phenomenon.
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PMID:Chicken anaemia virus infection: molecular basis of pathogenicity. 1864 63

The incidence of simian virus 40 (SV40) infections in rhesus macaques infected with simian-human immunodeficiency viruses (SHIV) and in uninfected animals was determined using PCR. Rates varied from 5% in peripheral blood mononuclear cells of uninfected monkeys to 19.6% in SHIV-infected macaques. Much higher detection rates, up to 75%, were found in lymph nodes and spleen samples of SHIV-infected animals. Sequence analysis of PCR amplicons revealed that they form two genetic clusters, one containing the majority of known SV40 strains and the other formed by variants with 7% genetic difference. Based on this difference, we propose two SV40 types: "type 1" or "classical type" for the majority of SV40 strains and "type 2" for the novel SV40 variants. The genome of one variant, SV40-Ri257, was completely sequenced and analyzed. The agnogene of SV40-Ri257 extends into the VP2 open reading frame and encodes a typical agnoprotein fused to a C-terminal hydrophobic region. The transcriptional control region (TCR) of SV40-Ri257 is the least conserved region compared to type 1 viruses. Particularly, the 3' end of the TCR, containing the early promoter and enhancer region, exhibits considerable variation. Further analysis of SHIV-infected macaques with type-specific PCRs revealed that the TCR of type 1 was completely conserved, whereas this region in type 2 varied considerably within the early enhancer region. We provide evidence here for the existence of a novel SV40 type in rhesus macaques and show that double infections with both types frequently occur.
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PMID:Molecular analysis of a novel simian virus 40 (SV40) type in rhesus macaques and evidence for double infections with the classical SV40 type. 2130 14

Infectious bursal disease virus (IBDV) induces immunodeficiency in young chickens and apoptosis in chicken embryos. To understand the relation between the viral pathogenesis and the induction of cell death, chicken embryonic fibroblast (CEF) cells were infected with IBDV intermediate (im) and very virulent (vv) strains at different MOIs. The cell viability and DNA fragmentation were evaluated in infected cells. The cellular apoptotic pathway involve was investigated by determining the activities of caspase cascade. The imIBDV strain was replicated well in CEF cells and shown higher viral titers than vvIBDV. Apoptosis changes were observed only in vvIBDV-infected CEF cells at higher MOI 48 h post infection. Efflux of cytochrome c suggests that the intrinsic pathway of the apoptotic process induced by vvIBDV infection independently of virus replication. Prediction of caspase substrates cleavage sites revealed that different IBDV strains have conserved cleavage motif pattern for VP2 and VP5 viral proteins. These findings suggest the pathogenicity of IBDV strains might be involved in the induction of apoptosis in host cells.
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PMID:Apoptotic response of chicken embryonic fibroblast cells to infectious bursal disease virus infections reflects viral pathogenicity. 2499 62

Most serological assays detect antibody responses in biological samples through affinity of serum antibodies for antigens provided in the assay. Certain antigens, however, may be difficult to produce and/or may contain unwanted epitopes. In these cases, a practical alternative may be the use of peptides as representatives for specific epitopes. Peptides can be obtained after purification in large quantities for a modest price, but screening of a large set of peptides during development may be relatively expensive. To cut costs of screening peptides for a new serological assay, the concept was investigated of using cheap non-purified (crude) peptides instead of purified peptides. Peptides were selected that represent three well-described linear epitopes of viral proteins: VP2 of canine parvovirus (CPV), gp41 of human immunodeficiency virus (HIV) and E2 of classical swine fever virus (CSFV). Crude and purified biotinylated peptides with either a short or long spacer between the biotin and the epitope were used to test their capability to bind antibodies in a bead-based suspension array. The results show that, in a bead-based suspension array, crude peptides can function as antigen for specific monoclonal antibodies, and that the acquired signals are less than with purified peptides. CSFV-derived crude peptides were also able to detect specific antibodies in swine serum, indicating the applicability of crude peptides for pre-screening large numbers of different peptides during the development of serological peptide-based assays.
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PMID:Pre-screening of crude peptides in a serological bead-based suspension array. 2854 17


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