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

The MN strain of human immunodeficiency virus type 1 was grown in H9 cells, concentrated by centrifugation, and disrupted, and proteins were purified by reversed-phase high-pressure liquid chromatography. Complete amino acid sequences were determined for the mature Gag proteins, showing natural proteolytic cleavage sites and the order of proteins (p17-p24-p2-p7-p1-p6) in the Gag precursors. At least two sequence variants of p24 and eight sequence variants of p17 were detected. The two most abundant variants of p24 and p17 represented at least 50% +/- 5% and 20% +/- 5% of their totals, respectively. These data suggest heterogeneity in the virus population, with 50% of the total virus containing the most abundant forms of p17 and p24 and 20% of the virus containing the second most abundant forms. The Gag precursors of these suggested viruses differ from each other by only 3 amino acid residues but differ from the precursors predicted by the published MN proviral DNA sequence by 10 residues. Electrospray ionization mass spectrometry analysis of the purified p24 forms showed that the measured molecular weight of the protein was 200 +/- 50 atomic mass units greater than the calculated molecular weight. The source of additional mass for the p24 forms was not determined, but the observation is consistent with previous suggestions that the protein is phosphorylated. Greater than 98% of the total recovered p17 was myristylated at the N-terminal glycine residue, and the measured molecular weights (as determined by electrospray ionization mass spectrometry) of the most abundant forms were within 3 atomic mass units of the calculated molecular weights (15,266).
 ...
PMID:Gag proteins of the highly replicative MN strain of human immunodeficiency virus type 1: posttranslational modifications, proteolytic processings, and complete amino acid sequences. 154 43

The entire and partial gag regions of human immunodeficiency virus type 1 (HIV-1) were overproduced in Escherichia coli and used for epitope mapping of antibodies against p17. We found that a mouse monoclonal antibody to p17, V17 recognizes the mature p17 but not the unprocessed Gag proteins containing the entire p17 moiety. Further analysis revealed that V17 recognizes the C-terminal 12-amino-acid region of p17 having free C-terminus. This monoclonal antibody may be useful for monitoring the maturation of virus particles.
 ...
PMID:A unique monoclonal antibody that recognizes mature p17 of HIV-1 but not its precursor. 158 67

Accumulating evidence suggests that the matrix (MA) protein of retroviruses plays a key role in virus assembly by directing the intracellular transport and membrane association of the Gag polyprotein. In this report, we show that the MA protein of human immunodeficiency virus type 1 is also critical for the incorporation of viral Env proteins into mature virions. Several deletions introduced in the MA domain (p17) of human immunodeficiency virus type 1 Gag polyprotein did not greatly affect the synthesis and processing of the Gag polyprotein or the formation of virions. Analysis of the viral proteins revealed normal levels of Gag and Pol proteins in these mutant virions, but the Env proteins, gp120 and gp41, were hardly detectable in the mutant virions. Our data suggest that an interaction between the viral Env protein and the MA domain of the Gag polyprotein is required for the selective incorporation of Env proteins during virus assembly. Such an interaction appears to be very sensitive to conformational changes in the MA domain, as five small deletions in two separate regions of p17 equally inhibited viral Env protein incorporation. Mutant viruses were not infectious in T cells. When mutant and wild-type DNAs were cotransfected into T cells, the replication of wild-type virus was also hindered. These results suggest that the incorporation of viral Env protein is a critical step for replication of retroviruses and can be a target for the design of antiviral strategies.
 ...
PMID:The matrix protein of human immunodeficiency virus type 1 is required for incorporation of viral envelope protein into mature virions. 162 61

The coding sequences of p17 and p24 of the Glasgow-8 strain of feline immunodeficiency virus (FIV) were amplified using the polymerase chain reaction and cloned into plasmid vectors. The predicted amino-acid sequences of FIV/Glasgow-8 p17 and p24 were compared with those of the Petaluma and PPR isolates of FIV. As seen with other retroviruses, these gag gene products are highly conserved, indicating that the protein products would be suitable antigens to detect anti-FIV antibodies in an immunoassay. Both p17 and p24 were stably expressed in Escherichia coli as fusion proteins with glutathione S transferase. A pure preparation of each fusion protein was obtained from induced bacterial lysates by affinity chromatography using glutathione-agarose beads. These recombinant proteins were used in an enzyme-linked immunosorbent assay to detect antibodies directed against FIV p17 and p24 in cat sera. This assay allows the identification of seropositive cats following infection with FIV and has greater sensitivity and specificity than a currently available immunodiagnostic test.
 ...
PMID:Immunodiagnosis of feline immunodeficiency virus infection using recombinant viral p17 and p24. 166 75

Levels of antibodies to six major structural proteins of human immunodeficiency virus type 1 (gp120, gp41, p66, p31, p24, and p17) were assessed in serial samples from 22 persons with severe hemophilia (16 asymptomatic and 6 who developed acquired immunodeficiency syndrome [AIDS] or AIDS-related complex) with an automated dot blot assay using purified recombinant antigens. High and sustained levels of antibody to gp120, gp41, and p31 were found in all patients irrespective of their clinical condition for 4 to 6 years after seroconversion. In contrast, immune response to p66 and p17 was significantly lower in symptomatic patients. Over time, the levels of these two antibodies, as well as anti-p24, decreased and tended to become undetectable. Abnormal immune response and low levels of antibody to p66 and p17 are early indications of rapid clinical progression.
 ...
PMID:Monitoring of specific antibodies to human immunodeficiency virus structural proteins: clinical significance. 167 48

The gag and pol genes of the human immunodeficiency virus type 1 (HIV-1) (ref. 1) are translated as two polyproteins, Pr55gag and Pr160gag-pol (refs 2-6), which are subsequently cleaved by the action of a virus-encoded protease into the four structural gag proteins of the virion core (p17, p24, p7 and p6) and the pol-encoded enzymes essential for retrovirus replication (protease, reverse transcriptase, ribonuclease H, and endonuclease). Mutational inactivation of the proteases of HIV-1 and other retroviruses results in immature, non-infectious virions, indicating that exogenous inhibition of the protease may represent an attractive approach to anti-AIDS therapy. Here we demonstrate that synthetic peptide analogues, which are potent inhibitors of purified HIV-1 protease, inhibit the processing of the viral polyproteins in cultures of HIV-1-infected T lymphocytes and attenuate viral infectivity.
 ...
PMID:Inhibition of HIV-1 protease in infected T-lymphocytes by synthetic peptide analogues. 168 46

Two monoclonal antibodies (MAbs) against p27 and one against p17 of simian immunodeficiency virus (SIV) from rhesus macaques were produced and characterized by reacting with disrupted, viral antigens on immunoblots. Human immunodeficiency virus type 1 (HIV-1), HIV-2 and SIV isolates from sooty mangabey, stump-tailed macaque, rhesus macaque and African green monkey (SIVSM, SIVStM, SIVMAC and SIVAGM) were used for comparative analysis. The p27 monoclonal antibodies HE3 and FA2 reacted with SIVMAC and SIVSM, but not with HIV-1, HIV-2, SIVStM and SIVAGM. The p17 monoclonal antibodies reacted with SIVMAC and SIVStM, but not HIV-1, HIV-2, SIVSM and SIVAGM. The differential reactivity of these monoclonal antibodies indicated that common conserved antigenic epitopes are shared between SIVMAC and SIVSM with respect to p27 MAbs and between SIVMAC and SIVStM with respect to p17. Since these MAbs reacted differently with the SIV isolates, they are useful reagents for comparative pathogenesis studies for differentiating SIV isolates.
 ...
PMID:Characterization of monoclonal antibodies that distinguish simian immunodeficiency virus isolates from each other and from human immunodeficiency virus types 1 and 2. 168 69

Studies on monitoring the immune response to viral structural proteins during human immunodeficiency virus (HIV-1) infection have established the significance of antibodies to the core protein p24 during the progression of the disease. We have studied the prevalence of antibodies to the core protein p17 in order to study their diagnostic and prognostic significance in the pathogenesis of HIV-1. Full-length HIV-1 p17, molecularly cloned and expressed in Escherichia coli was purified by immunoaffinity chromatography using an HIV-1 p17-specific monoclonal antibody. A highly sensitive enzyme-linked immunoassay was developed using the purified recombinant p17 as the serological target to detect antibodies to p17. The results indicated that antibodies to p17 decline during progression of disease, with the decline being more dramatic as patients moved from asymptomatic to AIDS-related complex (ARC). Patient specimens deficient in p24 antibody, but having detectable levels of antibody to p17 were almost always positive for p24 antigen. Under these conditions, p17 antibody is an important serological marker because it provides a more consistent marker for core antigens during HIV-1 infection.
 ...
PMID:Prevalence of antibodies to the core protein P17, a serological marker during HIV-1 infection. 169 27

A new type of immunochemical mapping of the human immunodeficiency virus type 1 (HIV-1) gag region was performed. By use of native HIV-1 viral lysates or the gag recombinant p24-15 antigen, a new set of monoclonal antibodies (Mabs) to the gag region proteins was generated. Synthetic HIV-1 peptides covering the entire gag region were used to specifically localize the continuous epitopes by direct binding to the Mabs and by blocking the Mab immunoreactivity. The identified immunogenic epitopes were localized between the gag amino acids (aa) 108-127, 203-217, 208-222, 248-282, 273-302, 288-307, 308-322, 331-354 and 408-422. These continuous epitopes formed seven immunogenic regions. One strongly p17-reactive Mab appeared to react with a discontinuous epitope, the components of which were 110 aa distant in the linear sequence: aa 23-27 and 128-132. The synthetic peptides appeared to be more congruent with the Mab-reactive sites in solution than when coated to a solid phase.
 ...
PMID:Epitope mapping of the HIV-1 gag region with monoclonal antibodies. 169 57

Evaluation of the immune response of individuals exposed to human immunodeficiency virus (HIV) is an important component of any plan designed to lead toward the development of an AIDS vaccine. Since the levels of antibodies to HIV p17 and the synthetic p17 peptide HGP-30 correlate with stages of progression to AIDS, studies were initiated to determine whether cytotoxic lymphocytes directed toward target cells pulsed with HGP-30 and radioactive chromium were present in seropositive individuals. The significance of such cells in controlling HIV viral infection has recently been enhanced by reports that HIV p17 is on the surface of infected cells and that an inactivated virus vaccine depleted of viral envelope appears to be effective in controlling expression. The selection of HGP-30 as the p17 peptide to be evaluated in early studies is based on the presence of both T-cell and B-cell epitopes as predicted by computer modeling and mouse studies and the demonstration of in vitro neutralization activity by antibodies to the epitope. By using B-lymphoblastoid cells pulsed with HGP-30 and radioactive chromium as autologous targets and mixed leukocyte culture-expanded peripheral blood lymphocytes as effectors, CD8+ cytotoxic T lymphocytes against HGP-30-coated targets were identified in seropositive individuals. In this report we demonstrate that a synthetic p17 epitope can be a target for major histocompatibility complex-restricted cytotoxic T lymphocytes in HIV-infected individuals.
 ...
PMID:HGP-30, a synthetic analogue of human immunodeficiency virus (HIV) p17, is a target for cytotoxic lymphocytes in HIV-infected individuals. 169 89


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