101
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Borkow G, Bentwich Z. Chronic immune activation associated with chronic helminthic and human immunodeficiency virus infections: role of hyporesponsiveness and anergy. Clin Microbiol Rev 2005; 17:1012-30, table of contents. [PMID: 15489359 PMCID: PMC523563 DOI: 10.1128/cmr.17.4.1012-1030.2004] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Chronic immune activation is one of the hallmarks of human immunodeficiency virus (HIV) infection. It is present also, with very similar characteristics, in very large human populations infested with helminthic infections. We have tried to review the studies addressing the changes in the immune profiles and responses of hosts infected with either one of these two chronic infections. Not surprisingly, several of the immune derangements and impairments seen in HIV infection, and considered by many to be the "specific" effects of HIV, can be found in helminth-infected but HIV-noninfected individuals and can thus be accounted for by the chronic immune activation itself. A less appreciated element in chronic immune activation is the immune suppression and anergy which it may generate. Both HIV and helminth infections represent this aspect in a very wide and illustrative way. Different degrees of anergy and immune hyporesponsiveness are present in these infections and probably have far-reaching effects on the ability of the host to cope with these and other infections. Furthermore, they may have important practical implications, especially with regard to protective vaccinations against AIDS, for populations chronically infected with helminths and therefore widely anergic. The current knowledge of the mechanisms responsible for the generation of anergy by chronic immune activation is thoroughly reviewed.
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Affiliation(s)
- Gadi Borkow
- Animal Scienes, Faculty of Agriculture, Hebrew University, Rehovot, Israel
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102
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103
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Virology. THE AIDS PANDEMIC 2005. [PMCID: PMC7148614 DOI: 10.1016/b978-012465271-2/50004-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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104
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Dong T, Stewart-Jones G, Chen N, Easterbrook P, Xu X, Papagno L, Appay V, Weekes M, Conlon C, Spina C, Little S, Screaton G, van der Merwe A, Richman DD, McMichael AJ, Jones EY, Rowland-Jones SL. HIV-specific cytotoxic T cells from long-term survivors select a unique T cell receptor. ACTA ACUST UNITED AC 2004; 200:1547-57. [PMID: 15596521 PMCID: PMC2212004 DOI: 10.1084/jem.20032044] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
HIV-specific cytotoxic T lymphocytes (CTL) are important in controlling HIV replication, but the magnitude of the CTL response does not predict clinical outcome. In four donors with delayed disease progression we identified Vβ13.2 T cell receptors (TCRs) with very similar and unusually long β-chain complementarity determining region 3 (CDR3) regions in CTL specific for the immunodominant human histocompatibility leukocyte antigens (HLA)-B8–restricted human immunodeficiency virus-1 (HIV-1) nef epitope, FLKEKGGL (FL8). CTL expressing Vβ13.2 TCRs tolerate naturally arising viral variants in the FL8 epitope that escape recognition by other CTL. In addition, they expand efficiently in vitro and are resistant to apoptosis, in contrast to FL8–specific CTL using other TCRs. Selection of Vβ13.2 TCRs by some patients early in the FL8-specific CTL response may be linked with better clinical outcome.
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Affiliation(s)
- Tao Dong
- Medical Research Council Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford OX3 9DS UK
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105
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Ferrari G, Neal W, Ottinger J, Jones AM, Edwards BH, Goepfert P, Betts MR, Koup RA, Buchbinder S, McElrath MJ, Tartaglia J, Weinhold KJ. Absence of immunodominant anti-Gag p17 (SL9) responses among Gag CTL-positive, HIV-uninfected vaccine recipients expressing the HLA-A*0201 allele. THE JOURNAL OF IMMUNOLOGY 2004; 173:2126-33. [PMID: 15265949 DOI: 10.4049/jimmunol.173.3.2126] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
According to a number of previous reports, control of HIV replication in humans appears to be linked to the presence of anti-HIV-1 Gag-specific CD8 responses. During the chronic phase of HIV-1 infection, up to 75% of the HIV-infected individuals who express the histocompatibility leukocyte Ag (HLA)-A*0201 recognize the Gag p17 SLYNTVATL (aa residues 77-85) epitope (SL9). However, the role of the anti-SL9 CD8 CTL in controlling HIV-1 infection remains controversial. In this study we determined whether the pattern of SL9 immunodominance in uninfected, HLA-A*0201 HIV vaccine recipients is similar to that seen in chronically HIV-infected subjects. The presence of anti-SL9 responses was determined using a panel of highly sensitive cellular immunoassays, including peptide:MHC tetramer binding, IFN-gamma ELISPOT, and cytokine flow cytometry. Thirteen HLA-A*0201 vaccinees with documented anti-Gag CD8 CTL reactivities were tested, and none had a detectable anti-SL9 response. These findings strongly suggest that the pattern of SL9 epitope immunodominance previously reported among chronically infected, HLA-A*0201-positive patients is not recapitulated in noninfected recipients of Gag-containing canarypox-based candidate vaccines and may be influenced by the relative immunogenicity of these constructs.
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Affiliation(s)
- Guido Ferrari
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA.
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106
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Fernández-Cruz E, Navarro J, Rodríguez-Sainz C, Gil J, Moreno S, González-Lahoz J, Carbone J. The potential role of the HIV-1 immunogen (Remune) as a therapeutic vaccine in the treatment of HIV infection. Expert Rev Vaccines 2004; 2:739-52. [PMID: 14711358 DOI: 10.1586/14760584.2.6.739] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Immune-based therapies, such as therapeutic vaccination, that might preserve, restore, enhance and induce new HIV-specific immunologic responses are currently being explored. HIV-specific immunotherapy with Remune (The Immune Response Corp.) offers the opportunity to boost immune responses against HIV-1. The clinical trial program in a wide range of subjects has established the efficacy of Remune in stimulating an appropriate immune response in HIV-positive individuals. Furthermore, a recent unblinded study conducted in Europe has documented a significant effect of Remune on viral load. Evidence regarding clinical end points is more difficult to collect. The same studies have revealed no serious safety issues in a total of more than 2000 Remune-treated patients. It is therefore reasonable to suggest that the risk-benefit ratio of Remune could be positive.
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Affiliation(s)
- Eduardo Fernández-Cruz
- University General Hospital Gregorio Marañón, Immunology Department, Complutense University of Madrid, Madrid, Spain.
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107
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Kurle S, Tripathy S, Jadhav S, Agnihotri K, Paranjape R. Full-length gag sequences of HIV type 1 subtype C recent seroconverters from Pune, India. AIDS Res Hum Retroviruses 2004; 20:1113-8. [PMID: 15585103 DOI: 10.1089/aid.2004.20.1113] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Although HIV-1 subtype C is the most prevalent subtype worldwide, data on subtype C viruses are rather limited. Very little information is available on the complete HIV-1 subtype C gag sequences from India. We report full-length gag (p55) sequences from six Indian early seroconverters. The samples were collected within few weeks of seroconversion and may represent immunologically naive viruses. The comparison of p55 sequences with other Indian and non-Indian subtype C sequences as well as with nonsubtype C sequences obtained from the Los Alamos database revealed gag as a well-conserved region of the HIV genome (range: 84-95%). The phylogenetic tree indicated that the sequences compared here cluster together within clade C. Two epitopes in the p24 region of the gag gene were subtype C specific while many epitopes in the same region were also present in other clades. The data on HIV-1 subtype C full-length gag sequences would be useful in the design and evaluation of effective subtype C-based HIV vaccines.
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Affiliation(s)
- Swarali Kurle
- Department of Molecular Virology, National AIDS Research Institute, Pune, India
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108
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Someya K, Xin KQ, Matsuo K, Okuda K, Yamamoto N, Honda M. A consecutive priming-boosting vaccination of mice with simian immunodeficiency virus (SIV) gag/pol DNA and recombinant vaccinia virus strain DIs elicits effective anti-SIV immunity. J Virol 2004; 78:9842-53. [PMID: 15331719 PMCID: PMC515009 DOI: 10.1128/jvi.78.18.9842-9853.2004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
To evaluate immunity induced by a novel DNA prime-boost regimen, we constructed a DNA plasmid encoding the gag and pol genes from simian immunodeficiency virus (SIV) (SIVgag/pol DNA), in addition to a replication-deficient vaccinia virus strain DIs recombinant expressing SIV gag and pol genes (rDIsSIVgag/pol). In mice, priming with SIVgag/pol DNA, followed by rDIsSIVgag/pol induced an SIV-specific lymphoproliferative response that was mediated by a CD4+-T-lymphocyte subset. Immunization with either vaccine alone was insufficient to induce high levels of proliferation or Th1 responses in the animals. The prime-boost regimen also induced SIV Gag-specific cellular responses based on gamma interferon secretion, as well as cytotoxic-T-lymphocyte responses. Thus, the regimen of DNA priming and recombinant DIs boosting induced Th1-type cell-mediated immunity, which was associated with resistance to viral challenge with wild-type vaccinia virus expressing SIVgag/pol, suggesting that this new regimen may hold promise as a safe and effective vaccine against human immunodeficiency virus type 1.
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Affiliation(s)
- Kenji Someya
- AIDS Research Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
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109
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Nakaya Y, Nakaya T, Park MS, Cros J, Imanishi J, Palese P, García-Sastre A. Induction of cellular immune responses to simian immunodeficiency virus gag by two recombinant negative-strand RNA virus vectors. J Virol 2004; 78:9366-75. [PMID: 15308731 PMCID: PMC506935 DOI: 10.1128/jvi.78.17.9366-9375.2004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A recombinant Newcastle disease virus (rNDV) expressing simian immunodeficiency virus (SIV) Gag protein (rNDV/SIVgag) was generated. The rNDV/SIVgag virus induced Gag-specific cellular immune responses in mice, leading to a specific anti-Gag antiviral immunity. This was evidenced by the inhibition of growth of recombinant vaccinia virus expressing an identical Gag antigen (rVac/SIVgag) but not of wild-type vaccinia virus in rNDV/SIVgag-immunized mice. Among intravenous, intraperitoneal, or intranasal immunization routes, intranasal administration induced the strongest protective response against challenge with rVac/SIVgag. We further demonstrated that these immune responses were greatly enhanced after booster immunization with recombinant influenza viruses expressing immunogenic portions of SIV Gag. The magnitude of the protective immune response correlated with the levels of cellular immune responses to Gag, which were still evident 9 weeks after immunization. These results suggest that rNDV and influenza virus vectors are suitable candidate vaccines against AIDS as well as against other infectious diseases.
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Affiliation(s)
- Yurie Nakaya
- Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA
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110
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Li L, Bouvier M. Structures of HLA-A*1101 complexed with immunodominant nonamer and decamer HIV-1 epitopes clearly reveal the presence of a middle, secondary anchor residue. THE JOURNAL OF IMMUNOLOGY 2004; 172:6175-84. [PMID: 15128805 DOI: 10.4049/jimmunol.172.10.6175] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
HLA-A*1101 is one of the most common human class I alleles worldwide. An increased frequency of HLA-A*1101 has been observed in cohorts of female sex workers from Northern Thailand who are highly exposed to HIV-1 and yet have remained persistently seronegative. In view of this apparent association of HLA-A*1101 with resistance to acquisition of HIV-1 infection, and given the importance of eliciting strong CTL responses to control and eliminate HIV-1, we have determined the crystal structure of HLA-A*1101 complexed with two immunodominant HIV-1 CTL epitopes: the nonamer reverse transcriptase(313-321) (AIFQSSMTK) and decamer Nef(73-82) (QVPLRPMTYK) peptides. The structures confirm the presence of primary anchor residues P2-Ile/-Val and P9-/P10-Lys, and also clearly reveal the presence of secondary anchor residues P6-Ser for reverse transcriptase and P7-Met for Nef. The overall backbone conformation of both peptides is defined as two bulges that are separated by a more buried middle residue. In this study, we discuss how this topology may offer functional advantages in the selection and presentation of HIV-1 CTL epitopes by HLA-A*1101. Overall, this structural analysis permits a more accurate definition of the peptide-binding motif of HLA-A*1101, the characterization of its antigenic surface, and the correlation of molecular determinants with resistance to HIV-1 infection. These studies are relevant for the rational design of HLA-A*1101-restricted CTL epitopes with improved binding and immunological properties for the development of HIV-1 vaccines.
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MESH Headings
- Alleles
- Crystallography, X-Ray
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/metabolism
- Female
- Gene Products, nef/chemistry
- Gene Products, nef/metabolism
- HIV Reverse Transcriptase/chemistry
- HIV Reverse Transcriptase/metabolism
- HIV-1/immunology
- HLA-A Antigens/chemistry
- HLA-A11 Antigen
- Humans
- Hydrogen Bonding
- Hydrophobic and Hydrophilic Interactions
- Immunodominant Epitopes/chemistry
- Immunodominant Epitopes/metabolism
- Peptide Fragments/chemistry
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- Protein Binding/immunology
- Protein Conformation
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/metabolism
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- Thermodynamics
- nef Gene Products, Human Immunodeficiency Virus
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Affiliation(s)
- Lenong Li
- School of Pharmacy, University of Connecticut, Storrs, CT 06269, USA
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111
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McKee HJ, T'sao PY, Vera M, Fortes P, Strayer DS. Durable cytotoxic immune responses against gp120 elicited by recombinant SV40 vectors encoding HIV-1 gp120 +/- IL-15. GENETIC VACCINES AND THERAPY 2004; 2:10. [PMID: 15324456 PMCID: PMC517511 DOI: 10.1186/1479-0556-2-10] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2003] [Accepted: 08/23/2004] [Indexed: 11/19/2022]
Abstract
Background A vaccine that elicits durable, powerful anti-HIV immunity remains an elusive goal. In these studies we tested whether multiple treatments with viral vector-delivered HIV envelope antigen (gp120), with and without IL-15, could help to approach that goal. For this purpose, we used recombinant Tag-deleted SV40-derived vectors (rSV40s), since they do not elicit neutralizing antibody responses, and so can be given multiply without loss of transduction efficiency. Methods SV(gp120) carried the coding sequences for HIV-1NL4-3 Env, and SV(mIL-15) carried the cDNA for mouse IL-15. Singly, and in combination, these two vectors were given monthly to BALB/cJ mice. Cytotoxic immunity and cytotoxic memory were tested in direct cytotoxicity assays using unselected effector cells. Antibody vs. gp120 was measured in a binding assay. In both cases, targets were P815 cells that were stably transfected with gp120. Results Multiple injections of SV(gp120) elicited powerful anti-gp120 cytolytic activity (>70% specific lysis) by unselected spleen cells. Cells from multiply-immunized mice that were rested 1 year after their last injections still showed >60% gp120-specific lysis. Anti-gp120 antibody was first detected after 2 monthly injections of SV(gp120) and remained elevated thereafter. Adding SV(mIL-15) to the immunization regimen dramatically accelerated the development of memory cytolytic responses, with ≥ 50% specific lysis seen 1 month after two treatments. IL-15 did not alter the development of antibody responses. Conclusions Thus, rSV40s encoding antigens and immunostimulatory cytokines may be useful tools for priming and/or boosting immune responses against HIV.
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Affiliation(s)
- Hayley J McKee
- Department of Pathology, Jefferson Medical College, Philadelphia, PA, USA
| | - Patricia Y T'sao
- Department of Pathology, Jefferson Medical College, Philadelphia, PA, USA
| | - Maria Vera
- School of Medicine. Foundation for Applied Medical Research. Division of Gene Therapy. Laboratory of Vector Development. University of Navarra. Irunlarrea 1. 31008. Pamplona. Spain
| | - Puri Fortes
- School of Medicine. Foundation for Applied Medical Research. Division of Gene Therapy. Laboratory of Vector Development. University of Navarra. Irunlarrea 1. 31008. Pamplona. Spain
| | - David S Strayer
- Department of Pathology, Jefferson Medical College, Philadelphia, PA, USA
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112
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Kan-Mitchell J, Bisikirska B, Wong-Staal F, Schaubert KL, Bajcz M, Bereta M. The HIV-1 HLA-A2-SLYNTVATL is a help-independent CTL epitope. THE JOURNAL OF IMMUNOLOGY 2004; 172:5249-61. [PMID: 15100263 DOI: 10.4049/jimmunol.172.9.5249] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The CTL response to the HLA-A*0201-restricted, HIV-1 p17 Gag(77-85) epitope (SLYNTVATL; SL9) has been extensively studied in patients. Although this reactivity is exceptionally prominent in chronically infected patients and inversely correlated to viral load, SL9-specific CTLs (SL9-CTLs) are rarely detected in acute infection. To explore the cellular basis for this unusual manifestation, SL9-CTLs primed ex vivo from naive circulating CD8(+) T cells of healthy, seronegative donors were generated and characterized. SL9 appeared to differ from other well-studied A*0201-restricted epitopes in several significant respects. In contrast to published reports for influenza and melanoma peptides and the HIV gag IV9 epitope studied here in parallel, SL9-CTLs were primed by immature but not mature autologous dendritic cells. Highly activated SL9-CTLs produce sufficient autocrine mediators to sustain clonal expansion and CTL differentiation for months without CD4(+) T cells or exogenous IL-2. Moreover, SL9-CTLs were sensitive to paracrine IL-2-induced apoptosis. IL-2 independence and sensitivity to paracrine IL-2 were also characteristic of SL9-CTLs immunized by dendritic cells transduced by a nonreplicating lentiviral vector encoding full-length Gag. In vitro-primed SL9-CTLs resembled those derived from patients in degeneracy of recognition and functional avidities for both SL9 and its natural mutations. Together, these data show that SL9 is a highly immunogenic, help-independent HIV epitope. The scarcity of SL9-CTLs in acute infection may result from cytokine-induced apoptosis with the intense activation of the innate immunity. In contrast, SL9-CTLs that constitutively produce autocrine help would predominate during CD4-diminished chronic infection.
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MESH Headings
- Antigen Presentation/genetics
- Antigen Presentation/immunology
- Cell Differentiation/immunology
- Cell Division/immunology
- Clone Cells
- Cytokines/physiology
- Cytotoxicity Tests, Immunologic
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Epitopes, T-Lymphocyte/immunology
- Gene Products, gag/immunology
- Genes, T-Cell Receptor beta
- Genetic Vectors
- HIV Antigens/immunology
- HIV-1/genetics
- HIV-1/immunology
- HLA-A Antigens/immunology
- HLA-A2 Antigen/immunology
- Humans
- Interleukin-2/pharmacology
- Lymphocyte Activation/immunology
- Lymphocyte Depletion
- Mutation
- Paracrine Communication/immunology
- Peptide Fragments
- Peptides/immunology
- Peptides/pharmacology
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- T-Lymphocytes, Cytotoxic/virology
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Helper-Inducer/metabolism
- Transduction, Genetic
- Viral Proteins/immunology
- env Gene Products, Human Immunodeficiency Virus
- gag Gene Products, Human Immunodeficiency Virus
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Affiliation(s)
- June Kan-Mitchell
- Karmanos Cancer Institute, Department of Pathology and Immunology, Wayne State University, Detroit, MI 48201, USA.
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113
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Egan MA. Current prospects for the development of a therapeutic vaccine for the treatment of HIV type 1 infection. AIDS Res Hum Retroviruses 2004; 20:794-806. [PMID: 15320982 DOI: 10.1089/0889222041725244] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Michael A Egan
- Department of Immunobiology, Wyeth Vaccines Research, Pearl River, New York, 10965, USA.
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114
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Wild J, Bojak A, Deml L, Wagner R. Influence of polypeptide size and intracellular sorting on the induction of epitope-specific CTL responses by DNA vaccines in a mouse model. Vaccine 2004; 22:1732-43. [PMID: 15068857 DOI: 10.1016/j.vaccine.2004.01.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have analysed the influence of size, intracellular localisation, and sorting of various human immunodeficiency virus type 1 (HIV-1)-derived Gag and Env polypeptides containing well defined H2(d)-restricted cytotoxic T lymphocyte (CTL) epitopes on the induction of a humoral and cellular immune response after DNA vaccination. Thus, expression vectors were generated based on RNA- and codon-optimised genes encoding (i). budding competent full-length Gag, (ii). a myristylation defect mutant GagMyr(-), (iii). the isolated p24 capsid moiety of Gag as well as variants of these proteins, which were C-terminally fused HIV gp120-derived V3 epitope (R10I), respectively. These constructs were compared to different minitopes each encoding one of the H2(d)-restricted Gag epitopes A9I and E10F or the V3 epitope R10I that were directly linked to the C-terminus of an Ad2-E3 protein-derived ER signal peptide. Immunological evaluation of these constructs in BALB/c mice revealed that both, the budding competent as well as the intracellular Gag proteins were-irrespective of their molecular weights-equally efficient in the priming of Gag-specific humoral and cellular immune responses. In addition, the capacity of these constructs to stimulate Gag-specific humoral as well as H2-K(d) and H2-L(d) restricted cellular immune responses was not influenced by C-terminal fusion of the immunodominant H2-D(d) restricted V3 epitope. Chimeric GagV3 polyproteins encoding all three major CTL epitopes within a continuous polyprotein were more efficient to stimulate epitope-specific cellular immune responses than the selected minitopes. In addition, the minitopes failed to induce epitope-specific antibody responses. These results clearly show the advantages of complex polypeptides over minitopes regarding the induction of strong humoral and cellular immune responses.
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Affiliation(s)
- Jens Wild
- Institute of Medical Microbiology, University of Regensburg, Franz-Josef-Strauss Allee 11, 93053 Regensburg, Germany
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115
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Majumder B, Gray B, McBurney S, Schaefer TM, Dentchev T, Mahalingam S, Reinhart TA, Ayyavoo V. Attenuated nef DNA vaccine construct induces cellular immune response: role in HIV-1 multiprotein vaccine. Immunol Lett 2004; 89:207-14. [PMID: 14556980 DOI: 10.1016/s0165-2478(03)00141-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
HIV-1 positive patients generate Nef-specific CTL response, indicating that Nef is a potent immunogen. However, Nef is also known to down regulate the expression of CD4 and MHC-I molecules, thereby protecting virally infected target cells. We compared the immunogenicity of non-functional nef vaccine constructs to wild type functional nef as potential immunogen. Mice were immunized with different nef constructs and assessed for their ability to induce cellular immune responses. Evaluation of T cell immune responses in mice showed that non-functional nef vaccine constructs are capable of inducing a significant T cell immune response measured by IFN-gamma ELISPOT. Further epitope mapping studies indicate that one of our attenuated constructs, Nef R-38, has multiple CTL epitopes spanning throughout the gene. Our results indicate that functionally attenuated Nef antigen might be a better candidate for future multiprotein HIV-1 vaccine.
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Affiliation(s)
- Biswanath Majumder
- Department of Infectious Diseases and Microbiology, University of Pittsburgh/GSPH, 130 DeSoto Street, Pittsburgh, PA 15261, USA
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116
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Gori A, Trabattoni D, Bandera A, Saresella M, Marchetti G, Gazzola L, Biasin M, Rhodes J, McDade H, Panebianco R, Galli M, Moroni M, Ferrante P, Thomas N, Franzetti F, Bray D, Clerici M. Immunomodulation Induced by Tucaresol in HIV Infection: Results of a 16 Week Pilot Phase I/II Trial. Antivir Ther 2004. [DOI: 10.1177/135965350400900418] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objective Immune reconstitution in highly active anti-retroviral therapy (HAART)-treated individuals is incomplete and immunomodulatory compounds are needed to improve the outcome of HIV therapy. In a Phase I/II clinical trial performed on HIV-positive patients we analysed the safety and immunomodulating effects of tucaresol, a novel compound that has previously been described to enhance cell-mediated immune responses. Patients and methods Sixteen weeks pulse dose escalation protocol. Four groups of HIV-positive patients were enrolled: group A ( n=6): HAART, CD4+ 300–500 cells/μl, HIV RNA <80 copies/ml; group B ( n=6): HAART-naive, CD4+ <500 cells/μl, HIV RNA >10 000 copies/ml; group C ( n=3): HAART-naive, CD4+ >500 cells/μl, HIV RNA <10 000 copies/ml; and group D ( n=6): HAART, CD4+ <200 cells/μl, HIV RNA <80 copies/ml. Tucaresol was added to HAART in group A and D patients; group B patients started tucaresol with HAART, group C patients received tucaresol alone. Clinical and immunological analyses were performed at different time points. Results Tucaresol-related serious adverse events were observed in the first week of therapy in 2/21 patients who were viraemic when commencing treatment, but did not occur in patients on stable HAART. Tucaresol did not affect HIV viraemia whereas increases in CD4+ percentages, mainly supported by naive CD4+ cells, were observed. CD8+/28-/45RA+ cells and HIV-specific CD8+ IFNγ- and perforin-producing cells improved whereas IL-10 mRNA diminished in tucaresol-treated patients. The effects were greater with 25 mg given every other day for 1 week. Conclusion In HAART-receiving patients with proper virus suppression, tucaresol was not associated with serious adverse events and resulted in qualitative and quantitative stimulation of HIV-specific cytotoxic T lymphocyte activity and generation of naive T cells. These data may support further exploration of tucaresol use in reconstitution of immune system parameters in HIV patients with proper virus suppression while on HAART.
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Affiliation(s)
- Andrea Gori
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | | | - Alessandra Bandera
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | - Marina Saresella
- Laboratory of Biology, ‘Don C Gnocchi’ Foundation, IRCCS, Milan, Italy
| | - Giulia Marchetti
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | - Lidia Gazzola
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | - Mara Biasin
- Department of Immunology, University of Milan, Milan, Italy
| | | | | | | | - Massimo Galli
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | - Mauro Moroni
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | | | | | - Fabio Franzetti
- Institute of Infectious Diseases and Tropical Medicine, ‘L Sacco’ Hospital, University of Milan, Milan, Italy
| | - Dorothy Bray
- Royal Free and University College Medical School, London, UK
| | - Mario Clerici
- Department of Immunology, University of Milan, Milan, Italy
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117
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Trabattoni D, Piconi S, Biasin M, Rizzardini G, Migliorino M, Seminari E, Boasso A, Piacentini L, Villa ML, Maserati R, Clerici M. Granule-dependent mechanisms of lysis are defective in CD8 T cells of HIV-infected, antiretroviral therapy-treated individuals. AIDS 2004; 18:859-69. [PMID: 15060433 DOI: 10.1097/00002030-200404090-00003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND HIV-specific cytotoxic T-cell (CTL) responses are defective in HIV-infected patients undergoing antiretroviral therapy (ART). This defect has been attributed to the decreased antigenic burden secondary to ART-associated suppression of HIV-replication, and is responsible for the rebounds of viraemia that occur when patients interrupt therapy. CTL are stimulated by type 1 cytokines and can kill targets via granule-dependent (perforin and granzymes) and -independent (tumour necrosis factor-alpha, CD95) mechanisms. METHODS Granule-dependent and granule-independent mechanisms of CTL killing, as well as type 1 cytokine production by CD4 T cells, were analysed in 57 chronically HIV-infected ART-treated or ART-untreated individuals. RESULTS The results can be summarized as follows: the frequency of gp160 (env)-specific interferon-gamma-secreting CD8 T lymphocytes correlates positively with HIV viraemia in ART-treated and -untreated patients; Env-specific perforin- and granzymes-expressing CD8 T lymphocytes, and Env-stimulated perforin and granzymes mRNA, are reduced in ART-treated patients independently of HIV viral load and of type 1 cytokine production; tumour necrosis factor-alpha production is increased in ART-treated individuals; and Env-specific immature CD8+28+27+ cells are only marginally augmented in ART-treated patients, Similar results are observed in cytomegalovirus-specific CD8 T cells and peripheral blood mononuclear cells. CONCLUSIONS A defect of CTL function that selectively affects the granule-dependent mechanisms of lysis is observed in ART-treated individuals. Because interferon-gamma production is higher in these patients, this could be a defect primarily involving CTL. These data suggest an independence of CD8 T-cell numbers and their lytic ability in HIV-infected, ART-receiving patients. Immunomodulants are needed to successfully treat HIV infection.
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Affiliation(s)
- Daria Trabattoni
- Department of Immunology, University of Milan, Via GB Grassi 74, 20157 Milan, Italy
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118
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Masemola A, Mashishi T, Khoury G, Mohube P, Mokgotho P, Vardas E, Colvin M, Zijenah L, Katzenstein D, Musonda R, Allen S, Kumwenda N, Taha T, Gray G, McIntyre J, Karim SA, Sheppard HW, Gray CM. Hierarchical targeting of subtype C human immunodeficiency virus type 1 proteins by CD8+ T cells: correlation with viral load. J Virol 2004; 78:3233-43. [PMID: 15016844 PMCID: PMC371059 DOI: 10.1128/jvi.78.7.3233-3243.2004] [Citation(s) in RCA: 177] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An understanding of the relationship between the breadth and magnitude of T-cell epitope responses and viral loads is important for the design of effective vaccines. For this study, we screened a cohort of 46 subtype C human immunodeficiency virus type 1 (HIV-1)-infected individuals for T-cell responses against a panel of peptides corresponding to the complete subtype C genome. We used a gamma interferon ELISPOT assay to explore the hypothesis that patterns of T-cell responses across the expressed HIV-1 genome correlate with viral control. The estimated median time from seroconversion to response for the cohort was 13 months, and the order of cumulative T-cell responses against HIV proteins was as follows: Nef > Gag > Pol > Env > Vif > Rev > Vpr > Tat > Vpu. Nef was the most intensely targeted protein, with 97.5% of the epitopes being clustered within 119 amino acids, constituting almost one-third of the responses across the expressed genome. The second most targeted region was p24, comprising 17% of the responses. There was no correlation between viral load and the breadth of responses, but there was a weak positive correlation (r = 0.297; P = 0.034) between viral load and the total magnitude of responses, implying that the magnitude of T-cell recognition did not contribute to viral control. When hierarchical patterns of recognition were correlated with the viral load, preferential targeting of Gag was significantly (r = 0.445; P = 0.0025) associated with viral control. These data suggest that preferential targeting of Gag epitopes, rather than the breadth or magnitude of the response across the genome, may be an important marker of immune efficacy. These data have significance for the design of vaccines and for interpretation of vaccine-induced responses.
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Affiliation(s)
- Agatha Masemola
- National Institute for Communicable Diseases, Johannesburg, South Africa
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119
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120
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Talal AH, Shata MT, Markatou M, Dorante G, Chadburn A, Koch R, Neumann AU, Ribeiro RM, Perelson AS. Virus dynamics and immune responses during treatment in patients coinfected with hepatitis C and HIV. J Acquir Immune Defic Syndr 2004; 35:103-13. [PMID: 14722440 DOI: 10.1097/00126334-200402010-00001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Mathematical modeling of the biological effect of interferon on virus decay permits the quantification of the efficacy (epsilon) of blocking virion production in different patient populations. The viral dynamic and immunologic responses of hepatitis C virus (HCV) infection to daily interferon therapy were characterized in twelve patients co-infected with human immunodeficiency virus (HIV). Three out of the twelve patients (25%) achieved an early viral response, a two-log reduction in HCV RNA by week 12. The mean epsilon of IFN-alpha in blocking HCV and HIV production were 72% and 74%, respectively. For HCV epsilon was highest (97%) in the one patient who had a sustained viral response, while it was reduced in the other two patients (68% and 77%). Baseline HCV RNA and the number of CD3+CD56+16+ cells were inversely related (r = -0.89, p = 0.03), and baseline HCV-specific immune responses were significantly higher in the three patients with 2-log viral load reductions. These data suggest that: 1) interferon efficacy at blocking virion production is correlated with treatment outcome in HIV/HCV co-infected patients, 2) that immunodeficient patients can respond to standard IFN-alpha, 3) that both innate and adaptive immune responses may be important determinants of HCV RNA decline in response to interferon.
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Affiliation(s)
- Andrew H Talal
- Department of Medicine, Weill Medical College of Cornell University, New York City, NY, USA.
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121
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Wilson CC, McKinney D, Anders M, MaWhinney S, Forster J, Crimi C, Southwood S, Sette A, Chesnut R, Newman MJ, Livingston BD. Development of a DNA vaccine designed to induce cytotoxic T lymphocyte responses to multiple conserved epitopes in HIV-1. THE JOURNAL OF IMMUNOLOGY 2004; 171:5611-23. [PMID: 14607970 DOI: 10.4049/jimmunol.171.10.5611] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Epitope-based vaccines designed to induce CTL responses specific for HIV-1 are being developed as a means for addressing vaccine potency and viral heterogeneity. We identified a set of 21 HLA-A2, HLA-A3, and HLA-B7 restricted supertype epitopes from conserved regions of HIV-1 to develop such a vaccine. Based on peptide-binding studies and phenotypic frequencies of HLA-A2, HLA-A3, and HLA-B7 allelic variants, these epitopes are predicted to be immunogenic in greater than 85% of individuals. Immunological recognition of all but one of the vaccine candidate epitopes was demonstrated by IFN-gamma ELISPOT assays in PBMC from HIV-1-infected subjects. The HLA supertypes of the subjects was a very strong predictor of epitope-specific responses, but some subjects responded to epitopes outside of the predicted HLA type. A DNA plasmid vaccine, EP HIV-1090, was designed to express the 21 CTL epitopes as a single Ag and tested for immunogenicity using HLA transgenic mice. Immunization of HLA transgenic mice with this vaccine was sufficient to induce CTL responses to multiple HIV-1 epitopes, comparable in magnitude to those induced by immunization with peptides. The CTL induced by the vaccine recognized target cells pulsed with peptide or cells transfected with HIV-1 env or gag genes. There was no indication of immunodominance, as the vaccine induced CTL responses specific for multiple epitopes in individual mice. These data indicate that the EP HIV-1090 DNA vaccine may be suitable for inducing relevant HIV-1-specific CTL responses in humans.
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MESH Headings
- AIDS Vaccines/administration & dosage
- AIDS Vaccines/chemical synthesis
- AIDS Vaccines/immunology
- Adult
- Amino Acid Motifs/immunology
- Animals
- Cell Line, Transformed
- Conserved Sequence/immunology
- Cytotoxicity Tests, Immunologic/methods
- Drug Evaluation, Preclinical
- Enzyme-Linked Immunosorbent Assay
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/isolation & purification
- HIV Infections/immunology
- HIV-1/immunology
- HIV-1/isolation & purification
- HLA-A2 Antigen/genetics
- HLA-A2 Antigen/immunology
- HLA-A3 Antigen/genetics
- HLA-A3 Antigen/immunology
- HLA-B7 Antigen/genetics
- HLA-B7 Antigen/immunology
- Histocompatibility Testing
- Humans
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/metabolism
- Leukocytes, Mononuclear/virology
- Mice
- Mice, Transgenic
- Predictive Value of Tests
- Superantigens/immunology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/virology
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/chemical synthesis
- Vaccines, DNA/immunology
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Affiliation(s)
- Cara C Wilson
- University of Colorado Health Sciences Center, Denver, CO 80262, USA
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122
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Nair MPN, Mahajan S, Hewitt R, Whitney ZRB, Schwartz SA. Association of drug abuse with inhibition of HIV-1 immune responses: studies with long-term of HIV-1 non-progressors. J Neuroimmunol 2004; 147:21-5. [PMID: 14741421 DOI: 10.1016/j.jneuroim.2003.10.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Recreational drug use has been proposed to affect the course of human immunodeficiency virus (HIV) infections. To investigate the effects of substance abuse on HIV infections, we compared virus-specific cytotoxic T lymphocyte (CTL) responses and the expression of IL-16, TGF-beta1, and CXCR4 in three different cohorts of HIV-infected patients: (1) long-term nonprogressors (LT-NPs) of HIV infection who do not use recreational drugs; (2) nondrugs using normal progressors (NPs), and (3) drugs using NPs. Our results show that LT-NPs manifest increased CTL activity and IL-16 expression and decreased expression of TGF-beta1 and CXCR4 compared to NPs, regardless of recreational drug usage. Furthermore, drugs using NPs showed significantly lower levels of CTL and IL-16 expression and increased TGF-beta1 and CXCR4 expression compared to nondrugs using NPs. Our results suggest that recreational drug use may reduce CTL and IL-16 expression and increase the expression of TGF-beta1 and CXCR4, all of which may facilitate progression of HIV infections.
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Affiliation(s)
- Madhavan P N Nair
- Department of Medicine and Microbiology, State University of New York at Buffalo, Kaleida Health/Buffalo General Hospital, 100 High Street, Buffalo, NY 14203, USA.
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123
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Keoshkerian E, Ashton LJ, Smith DG, Ziegler JB, Kaldor JM, Cooper DA, Stewart GJ, Ffrench RA. Effector HIV-specific cytotoxic T-lymphocyte activity in long-term nonprogressors: associations with viral replication and progression. J Med Virol 2004; 71:483-91. [PMID: 14556259 DOI: 10.1002/jmv.10525] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ex vivo effector cytotoxic T-lymphocyte (CTL) activity was assessed in 27 members of the Australian Long-Term Nonprogressor cohort and correlated with genetic, virological, and immunological markers. The 27 individuals were antiretroviral naive with CD4(+) T-cell counts of >500 cells/ microl for more than 8 years after human immunodeficiency virus type 1 (HIV-1) infection. Effector CTL activity was determined using a standard ex vivo chromium release assay. Individuals with CTL activity (HIV-1 env(IIIB) or pol or gag) were then compared to those without CTL activity in relation to plasma HIV-1 RNA, ICD p24 antigen, beta(2)-microglobulin, CD4 and CD8 T-cell counts, CCR5 and CCR2b genotypes, and progression to CD4 <500 cells/microl or commencement of antiretroviral treatment. Of the 27 individuals examined, 19 had no detectable effector CTL activity. The eight individuals with detectable CTL activity had significantly higher plasma levels of HIV-1 RNA (P = 0.014), immune complex dissociated p24 antigen (P = 0.006), and beta(2)-microglobulin (P = 0.009). There was increased risk of progression within 4 years of study entry in individuals with detectable effector CTL activity, higher plasma levels of HIV-1 RNA, higher beta(2)-microglobulin levels, and higher immune complex dissociated p24 antigen levels at enrollment (P = 0.017, P = 0.004, P = 0.027, P = 0.008 respectively). Multivariate analysis demonstrated viral load remained the strongest predictor of disease progression within this group (P = 0.017). There were no significant associations between CTL response and chemokine receptor genotype. These findings demonstrate the importance of HIV replication in generating an effector CTL response and show that effector CTL activity may be an early predictor of progression in people with long-term asymptomatic HIV infection.
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Affiliation(s)
- Elizabeth Keoshkerian
- Department of Immunology and Infectious Diseases, Sydney Children's Hospital, Randwick, Australia.
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124
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Vödrös D, Thorstensson R, Doms RW, Fenyö EM, Reeves JD. Evolution of coreceptor use and CD4-independence in envelope clones derived from SIVsm-infected macaques. Virology 2003; 316:17-28. [PMID: 14599787 DOI: 10.1016/s0042-6822(03)00579-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Coreceptor use of HIV can evolve during infection. We previously examined coreceptor use of related SIVsm inoculum viruses and sequential reisolates from cynomolgus macaques. These viruses exhibited broad coreceptor specificities and, generally, CCR5 use remained efficient and stable, while alternative coreceptor use decreased longitudinally. Here we demonstrate that individual envelopes (Envs) from inoculum and reisolate viruses fuse via a range of coreceptors, including CCR5, CCR8, CXCR6, GPR15, GPR1, and APJ. On the whole, coreceptor use of Envs from sequential reisolates recapitulated that of reisolate viruses, thus CCR5 use remained stable while alternative coreceptor use tended to decrease over time. Rhesus CCR5, GPR15, and CXCR6 supported fusion to a similar extent as their human counterparts. Additionally, a number of Envs mediated CD4-independent fusion via CCR5 and GPR15. Envs from different inoculum viruses exhibited distinct dependencies on CD4 for fusion via CCR5, ranging from strictly CD4-dependent to efficiently CD4-independent. Early reisolates from macaques infected with CD4-independent inoculums maintained or evolved Envs with a broad range of CD4-independence. CD4-independence became less variable/efficient in late reisolates from macaques that developed neutralizing antibodies. Infection with a CD4-dependent virus resulted in evolution of CD4-independent Envs in late reisolates. While CD4 independence can potentially broaden tropism in vivo, CD4-independent viruses are particularly sensitive to neutralizing antibodies. Therefore, interplay between receptor tropism and neutralization may shape viral evolution and SIV pathogenesis.
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Affiliation(s)
- Dalma Vödrös
- Department of Medical Microbiology, Dermatology and Infection, Lund University, Lund, Sweden
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125
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Altfeld M, Addo MM, Rosenberg ES, Hecht FM, Lee PK, Vogel M, Yu XG, Draenert R, Johnston MN, Strick D, Allen TM, Feeney ME, Kahn JO, Sekaly RP, Levy JA, Rockstroh JK, Goulder PJ, Walker BD. Influence of HLA-B57 on clinical presentation and viral control during acute HIV-1 infection. AIDS 2003; 17:2581-91. [PMID: 14685052 DOI: 10.1097/00002030-200312050-00005] [Citation(s) in RCA: 271] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND HLA-B57, as well as cytotoxic T-lymphocyte (CTL) responses restricted by this allele, have been strongly associated with long-term non-progressive chronic HIV-1 infection. However, their impact on viral replication during acute HIV-1 infection is not known. METHODS Clinical and immunological parameters during acute and early HIV-1 infection in individuals expressing HLA-B57 were assessed. HIV-1-specific T-cell responses were determined by peptide-specific interferon-gamma production measured using Elispot assay and flow-based intracellular cytokine quantification. RESULTS Individuals expressing HLA-B57 presented significantly less frequently with symptomatic acute HIV-1 infection (4/116, 3.4%) than expected from the frequency of chronically infected individuals expressing this allele (43/446, 9.6%; P < 0.05). During acute infection, virus-specific CD8 T-cell responses were dominated by HLA-B57-restricted responses, with significantly broader (P < 0.02) and stronger (P < 0.03) responses restricted by HLA-B57 than restricted by all other co-expressed HLA class I alleles combined. Six out of nine individuals expressing HLA-B57 controlled HIV-1 viremia in the absence of therapy at levels < 5000 copies/ml (median, 515 copies/ml) during up to 29 months following acute infection. CONCLUSION These data demonstrate that host genetic factors can influence the clinical manifestations of acute HIV-1 infection and provide a functional link between HLA-B57 and viral immune control.
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Affiliation(s)
- Marcus Altfeld
- Partners AIDS Research Center and Infectious Disease Division, Massachusetts General Hospital, Boston, Massachusetts, USA
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126
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Campbell TB, Schneider K, Wrin T, Petropoulos CJ, Connick E. Relationship between in vitro human immunodeficiency virus type 1 replication rate and virus load in plasma. J Virol 2003; 77:12105-12. [PMID: 14581547 PMCID: PMC253754 DOI: 10.1128/jvi.77.22.12105-12112.2003] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Although plasma human immunodeficiency virus type 1 (HIV-1) RNA concentration is a major determinant of the rate of HIV-1 disease progression, the reasons for variability in plasma virus loads among infected individuals are not fully understood. We conducted investigations with 15 HIV-1-infected individuals who were not receiving antiretroviral therapy to evaluate the hypothesis that HIV-1 replication rate in vitro is a significant determinant of plasma virus load. Virus could not be isolated from one subject. Two subjects were excluded because they had features previously associated with distinct plasma virus loads and altered rates of disease progression; one harbored a syncytium-inducing virus and the second was heterozygous for a 32-bp deletion from the CCR5 gene. HIV-1 replication rates were determined by culturing autologous virus isolates in phytohemagglutinin-treated peripheral blood mononuclear cells (PBMC) and determining the rate of p24 antigen production during the logarithmic phase of viral replication. The contribution of HIV-1 reverse transcriptase (RT) and protease (PR) alleles to replication capacity was assessed using recombinant viruses in a single-cycle infection assay. HIV-1 replication rates ranged from 0.15 to 0.76 log(10) pg/ml/day and were reproducible within the same donor PBMC (coefficient of variation +/- 4%). RT-PR replication capacity ranged from 14 to 95% of that of control virus and was linearly related to replication rate (r(2) = 0.53; P = 0.007). Plasma HIV-1 RNA concentration was linearly related to replication rate (r(2) = 0.71; P < 0.001) and RT-PR replication capacity (r(2) = 0.44; P = 0.019). These data suggest that different RT-PR alleles are important determinants of HIV-1 replication rates and that HIV-1 replication rate explains much of the variability in plasma virus load in chronic HIV-1 infection.
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Affiliation(s)
- Thomas B Campbell
- Division of Infectious Diseases, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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127
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Smith SM, Pentlicky S, Klase Z, Singh M, Neuveut C, Lu CY, Reitz MS, Yarchoan R, Marx PA, Jeang KT. An in vivo replication-important function in the second coding exon of Tat is constrained against mutation despite cytotoxic T lymphocyte selection. J Biol Chem 2003; 278:44816-25. [PMID: 12947089 DOI: 10.1074/jbc.m307546200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human and simian immunodeficiency virus (HIV/SIV) Tat proteins are specified by two coding exons. Tat functions in the transcription of primate lentiviruses. A plethora of in vitro data currently suggests that the second coding exon of Tat is largely devoid of function. However, whether the second exon of Tat contributes functionally to viral pathogenesis in vivo remains unknown. To address this question directly, we compared infection of rhesus macaques with an SIV, engineered to express only the first coding exon of Tat (SIVtat1ex), to counterpart infection with wild-type SIVmac239 virus, which expresses the full 2-exon Tat. This comparison showed that the second coding exon of Tat contributes to chronic SIV replication in vivo. Interestingly, in macaques, we observed a cytotoxic T lymphocytes (CTL) response to the second coding exon of Tat, which appears to durably control SIV replication. When SIV mutated in an attempt to escape this second Tat-exon-CTL, the resulting virus was less replicatively fit and failed to populate the host in vivo. Our study provides the first evidence that the second coding exon in Tat embodies an important function for in vivo replication. We suggest the second coding exon of Tat as an example of a functionally constrained "epitope" whose elicited CTL response cannot be escaped by virus mutation without producing a virus that replicates poorly in vivo.
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Affiliation(s)
- Stephen M Smith
- Saint Michael's Medical Center, Newark, New Jersey 07102, USA.
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128
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Yang OO, Sarkis PTN, Trocha A, Kalams SA, Johnson RP, Walker BD. Impacts of Avidity and Specificity on the Antiviral Efficiency of HIV-1-Specific CTL. THE JOURNAL OF IMMUNOLOGY 2003; 171:3718-24. [PMID: 14500671 DOI: 10.4049/jimmunol.171.7.3718] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Although CD8(+) CTLs are presumed to be an important mediator of protective immunity in HIV-1 infection, the factors that determine CTL antiviral efficiency are poorly understood. Two factors that have been proposed to influence CTL antiviral function are antigenic avidity and epitope specificity. In this study we evaluate these by examining the activity of HIV-1-specific CTL against acutely infected cells. The ability of CTL to kill infected cells is variable and depends more on epitope specificity than functional avidity within the range for the tested clones (50% of maximal killing, 50 pg/ml to 100 ng/ml); killing efficiency is similar for different clones recognizing the same epitope, despite their variation in avidity. When CTL clones are tested for their ability to suppress viral replication, similar results are observed. Inhibition is more dependent on epitope specificity than functional avidity among the tested clones (50% of maximal killing, 20 pg/ml to 20 ng/ml). Thus, CTL specificity can be an overriding factor in the ability of CTL to interact with HIV-1-infected cells, indicating that factors determining the process of epitope presentation on infected cells have a key influence on CTL efficiency. These results suggest that CTL specificity may have a pivotal role in the immunopathogenesis of infection, and that simple quantitative measures of CTL may be insufficient indicators of the CTL response to HIV-1.
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MESH Headings
- Antiviral Agents/immunology
- Cell Death/immunology
- Cell Line
- Clone Cells
- Coculture Techniques
- Cytotoxicity Tests, Immunologic/methods
- Cytotoxicity, Immunologic
- Epitopes, T-Lymphocyte/immunology
- Gene Products, env/immunology
- Gene Products, env/metabolism
- Gene Products, gag/immunology
- Gene Products, gag/metabolism
- Gene Products, nef/immunology
- Gene Products, nef/metabolism
- Gene Products, pol/immunology
- Gene Products, pol/metabolism
- HIV-1/growth & development
- HIV-1/immunology
- Humans
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- T-Lymphocytes, Cytotoxic/virology
- Virus Replication/immunology
- nef Gene Products, Human Immunodeficiency Virus
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Affiliation(s)
- Otto O Yang
- Division of Infectious Diseases and AIDS Institute, University of California, Los Angeles Medical Center, Los Angeles, CA 90095, USA.
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129
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Mealey RH, Zhang B, Leib SR, Littke MH, McGuire TC. Epitope specificity is critical for high and moderate avidity cytotoxic T lymphocytes associated with control of viral load and clinical disease in horses with equine infectious anemia virus. Virology 2003; 313:537-52. [PMID: 12954220 PMCID: PMC3342690 DOI: 10.1016/s0042-6822(03)00344-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Equine infectious anemia virus (EIAV) is a lentivirus that causes persistent infections in horses. We hypothesized that high-avidity CTL specific for nonvariable epitopes might be associated with low viral load and minimal disease in EIAV-infected horses. To test this hypothesis, memory CTL (CTLm) responses were analyzed in two infected horses with high plasma viral loads and recurrent disease (progressors), and in two infected horses with low-to-undetectable viral loads and mild disease (nonprogressors). High-avidity CTLm in one progressor recognized an envelope gp90 epitope, and the data documented for the first time in EIAV that viral variation led to CTL escape. Each of the nonprogressors had high-to-moderate avidity CTLm directed against epitopes within Rev, including the nuclear export and nuclear localization domains. These results suggested that the epitope specificity of high- and moderate-avidity CTLm was an important determinant for disease outcome in the EIAV-infected horses examined.
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Affiliation(s)
- Robert H Mealey
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA.
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130
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Rayevskaya M, Kushnir N, Frankel FR. Anti-human immunodeficiency virus-gag CD8+ memory T cells generated in vitro from Listeria-immunized mice. Immunology 2003; 109:450-60. [PMID: 12807492 PMCID: PMC1782980 DOI: 10.1046/j.1365-2567.2003.01669.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The goal of vaccination is the generation of immune memory, an immune state that permits rapid and intense recall responses to a pathogen. Considerable effort is being made to understand the nature of memory T cells. We report here that by extending the length of in vitro culture following a single restimulation with specific peptide, preparations of highly enriched, highly active antigen-specific CD8+ memory T cells could be obtained. These cultures were begun with splenocytes from mice primed by infection either with an attenuated strain of Listeria monocytogenes or vaccinia virus, both expressing the human immunodeficiency virus-1-gag gene. In the cultures, antigen-specific cytotoxic T lymphocyte (CTL) activity reached a maximum at about 9 days and thereafter fell to negligible values. Concomitant with the fall of CTL activity, however, we observed enrichment for a subset of CD11ahigh antigen-specific gag-tetramerpos CD8+ T cells. The cells showed little or no 4-hr CTL activity, but had high delayed (18-hr) CTL activity, and very high cytolytic activity after restimulation. They rapidly expressed interferon-gamma production. Their growth and survival after sorting was completely dependent on interleukin-2 or -15. As few as 5000 of the fluorescence-activated cell sorting-purified cells protected recipients against challenge 3 months after transfer. In response to the challenge, the cells repopulated lymphoid and non-lymphoid organs and showed a sizeable increase in number. The cells therefore demonstrate high protective activity for long periods of time. These cultured cells are thus a potential source of enriched natural memory T cells for reperfusion studies and in which the mechanisms that underlie the generation, differentiation and persistence of memory can be examined.
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Affiliation(s)
- Marina Rayevskaya
- Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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131
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Alter G, Hatzakis G, Tsoukas CM, Pelley K, Rouleau D, LeBlanc R, Baril JG, Dion H, Lefebvre E, Thomas R, Côté P, Lapointe N, Routy JP, Sékaly RP, Conway B, Bernard NF. Longitudinal assessment of changes in HIV-specific effector activity in HIV-infected patients starting highly active antiretroviral therapy in primary infection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 171:477-88. [PMID: 12817033 DOI: 10.4049/jimmunol.171.1.477] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Both the magnitude and breadth of HIV-specific immunity were evaluated longitudinally on samples collected from six subjects starting highly active antiretroviral therapy (HAART) preseroconversion (group 1), 11 recently infected subjects starting HAART postseroconversion (group 2), five subjects starting HAART in the second half of the first year of infection (group 3), and six persons starting treatment in the chronic phase of infection (group 4). HIV-specific immunity was measured by IFN-gamma ELISPOT, detecting the frequency of cells responding to a panel of HLA-restricted HIV-1 peptides. Intracellular cytokine staining was used to detect the frequency of HIV-1 Gag p55-specific CD4(+) and CD8(+) T cells in a subset of participants. The magnitude and breadth of HIV-specific responses persisted in all group 1 subjects and in 5 of 11 (45%) group 2 subjects. Both of these parameters declined in 6 of 11 (55%) group 2 and in all group 3 and 4 individuals. All persons who maintained detectable numbers of HIV-1 Gag p55-specific CD4(+) and CD8(+) T cells after starting HAART preserved the intensity and breadth of their HIV-specific effector response. Our results show that HIV-specific immunity can be preserved even if HAART is initiated beyond the acute phase of infection.
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Affiliation(s)
- G Alter
- McGill University Health Center, Montreal, Quebec, Canada
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132
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Baumeister MA, Chattergoon MA, Weiner DB. Prospects for an HIV vaccine: conventional approaches and DNA immunization. Biotechnol Genet Eng Rev 2003; 19:205-42. [PMID: 12520879 DOI: 10.1080/02648725.2002.10648030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Mark A Baumeister
- University of Pennsylvania School of Medicine, Department of Pathology and Laboratory Medicine, 505 Stellar-Chance Laboratories, 422 Curie Blvd., Philadelphia, PA 19104, USA
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133
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Geffin R, Hutto C, Andrew C, Scott GB. A longitudinal assessment of autologous neutralizing antibodies in children perinatally infected with human immunodeficiency virus type 1. Virology 2003; 310:207-15. [PMID: 12781708 DOI: 10.1016/s0042-6822(03)00137-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The evolution of autologous neutralizing antibodies to sequential human immunodeficiency virus type 1 (HIV-1) isolates was studied in a population of 16 children who were perinatally infected with human immunodeficiency virus type 1. The cohort included seven children with rapid disease progression (RP) and nine who had nonrapid disease progression (NRP). Four of the NRP after 6 months of age harbored viruses that could be neutralized by antibodies found in autologous contemporaneous plasma (titers up to 1:640) while the majority of longitudinally collected viruses from five NRP were resistant to neutralization with contemporaneous plasma. Because of their shorter survival, only five of the RP had studies after 6 months of age; three of the five had neutralizing antibodies to contemporaneous virus isolates and the highest titers were 1:20. The highest titers in RP (up to 1:160) occurred in specimens obtained prior to 6 months of age but these were most likely of maternal origin. Most isolates that were not neutralized by contemporaneous plasma could be neutralized using noncontemporaneous plasma obtained months to years after the virus isolates. These autologous noncontemporaneous neutralizing antibodies persisted for years, had titers that were higher to viruses isolated at younger ages, and were generally more potent in children with NRP than RP. Demonstration of neutralizing antibodies to viruses previously resistant to neutralization by contemporaneous plasma suggests a continuous evolution of virus variants in vivo that are able to escape the effect of neutralizing antibodies.
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Affiliation(s)
- Rebeca Geffin
- Department of Pediatrics, University of Miami School of Medicine, Miami, FL 33136, USA.
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134
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Autran B, Debré P, Walker B, Katlama C. Therapeutic vaccines against HIV need international partnerships. Nat Rev Immunol 2003; 3:503-8. [PMID: 12776210 DOI: 10.1038/nri1107] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The successes of anti-retroviral treatments against HIV are limited today by the cost and toxicity of lifelong administration. An innovative therapeutic strategy has been proposed to boost the immune system of infected patients with HIV vaccines and to help limit the use of anti-retroviral treatments. This perspective article reviews the crucial questions raised by such a strategy and the main international efforts that are already set up to provide rapid answers--in particular, a not-for-profit international network that is dedicated to the development of therapeutic immunization programmes against HIV.
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Affiliation(s)
- Brigitte Autran
- Laboratoire d'Immunologie Cellulaire, Centre Hospitalier Universitaire Pitié-Salpétrière, 75651 Paris, France.
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135
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Cao J, McNevin J, Holte S, Fink L, Corey L, McElrath MJ. Comprehensive analysis of human immunodeficiency virus type 1 (HIV-1)-specific gamma interferon-secreting CD8+ T cells in primary HIV-1 infection. J Virol 2003; 77:6867-78. [PMID: 12768006 PMCID: PMC156203 DOI: 10.1128/jvi.77.12.6867-6878.2003] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1)-specific CD8(+) T cells provide an important defense in controlling HIV-1 replication, particularly following acquisition of infection. To delineate the breadth and potency of these responses in patients upon initial presentation and before treatment, we determined the fine specificities and frequencies of gamma interferon (IFN-gamma)-secreting CD8(+) T cells recognizing all HIV-1 proteins in patients with primary infection. In these subjects, the earliest detected responses were directed predominantly against Nef, Tat, Vpr, and Env. Tat- and Vpr-specific CD8(+) T cells accounted for the greatest frequencies of mean IFN-gamma spot-forming cells (SFC). Nef-specific responses (10 of 21) were more commonly detected. A mean of 2.3 epitopes were recognized with various avidities per subject, and the number increased with the duration of infection (R = 0.47, P = 0.031). The mean frequency of CD8(+) T cells (985 SFC/10(6) peripheral blood mononuclear cells) correlated with the number of epitopes recognized (R = 0.84, P < 0.0001) and the number of HLA-restricting alleles (R = 0.79, P < 0.0001). Neither the total SFC frequencies nor the number of epitopes recognized correlated with the concurrent plasma viral load. Seventeen novel epitopes were identified, four of which were restricted to HLA alleles (A23 and B72) that are common among African descendents. Thus, primary HIV-1 infection induces strong CD8(+)-T-cell immunity whose specificities broaden over time, but their frequencies and breadth do not correlate with HIV-1 containment when examined concurrently. Many novel epitopes, particularly directed to Nef, Tat, and Env, and frequently with unique HLA restrictions, merit further consideration in vaccine design.
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Affiliation(s)
- Jianhong Cao
- Program in Infectious Diseases, Clinical Research Division, Fred Hutchinson Cancer Research Center and Department of Medicine, University of Washington, Seattle, Washington 98109, USA
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136
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Affiliation(s)
- Steven G Deeks
- Positive Health Program, San Francisco General Hospital, University of California, San Francisco, 94110, USA.
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137
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Yang OO, Sarkis PTN, Ali A, Harlow JD, Brander C, Kalams SA, Walker BD. Determinant of HIV-1 mutational escape from cytotoxic T lymphocytes. J Exp Med 2003; 197:1365-75. [PMID: 12743169 PMCID: PMC2193781 DOI: 10.1084/jem.20022138] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
CD8+ class I-restricted cytotoxic T lymphocytes (CTLs) usually incompletely suppress HIV-1 in vivo, and while analogous partial suppression induces antiretroviral drug-resistance mutations, epitope escape mutations are inconsistently observed. However, escape mutation depends on the net balance of selective pressure and mutational fitness costs, which are poorly understood and difficult to study in vivo. Here we used a controlled in vitro system to evaluate the ability of HIV-1 to escape from CTL clones, finding that virus replicating under selective pressure rapidly can develop phenotypic resistance associated with genotypic changes. Escape varied between clones recognizing the same Gag epitope or different Gag and RT epitopes, indicating the influence of the T cell receptor on pressure and fitness costs. Gag and RT escape mutations were monoclonal intra-epitope substitutions, indicating limitation by fitness constraints in structural proteins. In contrast, escape from Nef-specific CTL was more rapid and consistent, marked by a polyclonal mixture of epitope point mutations and upstream frameshifts. We conclude that incomplete viral suppression by CTL can result in rapid emergence of immune escape, but the likelihood is strongly determined by factors influencing the fitness costs of the particular epitope targeted and the ability of responding CTL to recognize specific epitope variants.
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Affiliation(s)
- Otto O Yang
- Division of Infectious Diseases, 37-121 CHS, UCLA Medical Center, 10833 LeConte Ave., Los Angeles, CA 90095, USA.
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138
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Bu Z, Ye L, Compans RW, Yang C. Enhanced cellular immune response against SIV Gag induced by immunization with DNA vaccines expressing assembly and release-defective SIV Gag proteins. Virology 2003; 309:272-81. [PMID: 12758174 DOI: 10.1016/s0042-6822(03)00066-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Codon-optimized genes were synthesized for the SIVmac239 Gag, a mutant Gag with mutations in the major homology region, and a chimeric Gag containing a protein destruction signal at the N-terminus of Gag. The mutant and chimeric Gag were expressed at levels comparable to that observed for the wild-type Gag protein but their stability and release into the medium were found to be significantly reduced. Immunization of mice with DNA vectors encoding the mutant or chimeric Gag induced fourfold higher levels of anti-SIV Gag CD4 T cell responses than the DNA vector encoding the wild-type SIV Gag. Moreover, anti-SIV Gag CD8 T cell responses induced by DNA vectors encoding the mutant or chimeric Gag were found to be 5- to 10-fold higher than those induced by the DNA construct for the wild-type Gag. These results indicate that mutations disrupting assembly and/or stability of the SIV Gag protein effectively enhance its immunogenicity when expressed from DNA vaccines.
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Affiliation(s)
- Zhigao Bu
- Department of Microbiology and Immunology, Emory University School of Medicine, 1510 Clifton Road, Room 3086, Rollins Research Center, Atlanta, GA 30322, USA
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139
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Xu J, Lori F, Lisziewicz J. Vaccinia assay for the rapid detection of functional HIV-specific CD8+ cytotoxic T lymphocytes. J Immunol Methods 2003; 276:45-57. [PMID: 12738358 DOI: 10.1016/s0022-1759(03)00064-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Human immunodeficiency virus (HIV)-specific T cells play a critical role in anti-virus immunity. Therefore, during the clinical development of immune-based therapies, it is important to perform a diagnostic test that rapidly quantifies and characterizes cellular immune responses. For detection of functional HIV-specific CD8(+) cytotoxic T cells (CTL), we used a rapid vaccinia assay that employs recombinant vaccinia virus-infected peripheral blood mononuclear cells (PBMC). This assay was compared with the traditional 51Cr-release CTL assay and with the peptide pool-based enzyme-linked immunospot assay (ELISPOT). We demonstrated a close correlation between these assays by using identical antigens in parallel assays. However, the vaccinia assay was the least expensive and time- and labor-consuming test. Regarding sensitivity, the vaccinia assay was similar to both the peptide pool-based ELISPOT and CTL assays. We showed that human histocompatibility leukocyte antigen (HLA)-Dr(+) cells are responsible for presenting recombinant vaccinia antigens to T cells. The recombinant vaccinia-based assay is a rapid, sensitive and quantitative test and is thus suitable for the detection of functional antigen-specific CD8(+) CTL in large-scale clinical studies.
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Affiliation(s)
- Jianqing Xu
- Research Institute for Genetic and Human Therapy (RIGHT), Washington, DC, USA
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140
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Khatissian E, Monceaux V, Cumont MC, Ho Tsong Fang R, Estaquier J, Hurtrel B. Simian immunodeficiency virus infection of CD4+CD8+ T cells in a macaque with an unusually high peripheral CD4+CD8+ T lymphocyte count. AIDS Res Hum Retroviruses 2003; 19:267-74. [PMID: 12804002 DOI: 10.1089/088922203764969465] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We assessed the possible role in vivo CD4(+) CD8(+) T cells as a viral reservoir for simian immunodeficiency virus (SIV), in a macaque with 50% CD4(+) CD8(+) T cells in peripheral blood. During primary infection (day 14) of this rhesus macaque with the pathogenic SIVmac251 strain, proviruses were detected at similar frequencies in CD4(+) CD8(+) T cells (1/10) and CD4(+) T cells (1/10) and at a lower frequency in CD8(+) T cells (1/800). On day 235, no viral DNA was detected in CD8(+) cells, despite the persistent high viral load, indicating that CD8(+) cells do not constitute a reservoir during the chronic phase of SIV infection. Infection induced early lymphopenia of CD4(+), CD4(+) CD8(+), and CD8(+) cells; only the CD8(+) cell population returned to initial levels and expanded further. We found that CD4(+) CD8(+) T cells expressed the costimulatory CD28 molecule less and were more prone to die in vitro after phytohemagglutinin/interleukin 2 stimulation than were CD4(+) T cells. Taken together, massive death of CD4(+) CD8(+) T cells during acute stages of SIV infection may explain why CD8(+) T cells did not represent a major reservoir for SIV at the onset of infection.
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Affiliation(s)
- Emmanuel Khatissian
- Unité de Physiopathologie des Infections Lentivirales, Institut Pasteur, 75724 Paris Cedex 15, France.
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141
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Keeney TS, Nomura LE, Maecker HT, Sastry KJ. Flow cytometric analysis of macaque whole blood for antigen-specific intracellular cytokine production by T lymphocytes. J Med Primatol 2003; 32:23-30. [PMID: 12733599 DOI: 10.1034/j.1600-0684.2003.00005.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We report here the standardized conditions for stimulation of macaque whole blood samples with various protein or peptide antigens, and production of significant intracellular levels of interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) in CD4+ as well as CD8+ T lymphocytes. We observed significantly higher levels of TNF-alpha compared with IFN-gamma in both CD4+ and CD8+ T lymphocytes from all the macaque whole blood samples stimulated with staphylococcal enterotoxin B (SEB) as an antigen. Similarly, when whole blood samples from rhesus macaques immunized with an HIV envelope peptide cocktail vaccine were stimulated with either the peptide cocktail or recombinant gp160, we observed production of significant levels of TNF-alpha by both CD4+ and CD8+ T lymphocytes. These results strongly support the utility of the whole blood cytokine flow cytometry methodology for determining antigen-specific immune responses of macaques in vaccine studies.
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Affiliation(s)
- Talitha S Keeney
- Department of Veterinary Sciences, The University of Texas M. D. Anderson Cancer Center, Bastrop, TX 78602, USA
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142
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Ridgely SL, Zhang B, McGuire TC. Response of ELA-A1 horses immunized with lipopeptide containing an equine infectious anemia virus ELA-A1-restricted CTL epitope to virus challenge. Vaccine 2003; 21:491-506. [PMID: 12531649 DOI: 10.1016/s0264-410x(02)00474-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Lipopeptide containing an ELA-A1-restricted cytotoxic T lymphocyte (CTL) epitope from the envelope surface unit (SU) protein of the EIAV(WSU5) strain was used to immunize three horses having the ELA-A1 haplotype. Peptide-specific ELA-A1-restricted CTL were induced in all three horses, although these were present transiently in PBMC. These horses were further immunized with lipopeptide containing the corresponding CTL epitope from the EIAV(PV) strain. Then, the three immunized horses and three non-immunized horses were challenged by intravenous inoculation with 300 TCID(50) EIAV(PV). All horses developed cell free viremia, fever and thrombocytopenia. However, there was a statistically lower fever and thrombocytopenia severity score in the immunized group. Shorter duration of plasma viral load in two of the three immunized horses likely explains the less severe clinical disease in this group. Results indicate that lipopeptide immunization had a protective effect against development of clinical disease following virus challenge.
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Affiliation(s)
- Sherritta L Ridgely
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
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143
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Willey RL, Byrum R, Piatak M, Kim YB, Cho MW, Rossio JL, Bess J, Igarashi T, Endo Y, Arthur LO, Lifson JD, Martin MA. Control of viremia and prevention of simian-human immunodeficiency virus-induced disease in rhesus macaques immunized with recombinant vaccinia viruses plus inactivated simian immunodeficiency virus and human immunodeficiency virus type 1 particles. J Virol 2003; 77:1163-74. [PMID: 12502833 PMCID: PMC140830 DOI: 10.1128/jvi.77.2.1163-1174.2003] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
An effective vaccine against the human immunodeficiency virus type 1 (HIV-1) will very likely have to elicit both cellular and humoral immune responses to control HIV-1 strains of diverse geographic and genetic origins. We have utilized a pathogenic chimeric simian-human immunodeficiency virus (SHIV) rhesus macaque animal model system to evaluate the protective efficacy of a vaccine regimen that uses recombinant vaccinia viruses expressing simian immunodeficiency virus (SIV) and HIV-1 structural proteins in combination with intact inactivated SIV and HIV-1 particles. Following virus challenge, control animals experienced a rapid and complete loss of CD4(+) T cells, sustained high viral loads, and developed clinical disease by 17 to 21 weeks. Although all of the vaccinated monkeys became infected, they displayed reduced postpeak viremia, had no significant loss of CD4(+) T cells, and have remained healthy for more than 15 months postinfection. CD8(+) T-cell and neutralizing antibody responses in vaccinated animals following challenge were demonstrable. Despite the control of disease, virus was readily isolated from the circulating peripheral blood mononuclear cells of all vaccinees at 22 weeks postchallenge, indicating that immunologic control was incomplete. Virus recovered from the animal with the lowest postchallenge viremia generated high virus loads and an irreversible loss of CD4(+) T-cell loss following its inoculation into a naïve animal. These results indicate that despite the protection from SHIV-induced disease, the vaccinated animals still harbored replication-competent and pathogenic virus.
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Affiliation(s)
- Ronald L Willey
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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144
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Novitsky V, Gilbert P, Peter T, McLane MF, Gaolekwe S, Rybak N, Thior I, Ndung'u T, Marlink R, Lee TH, Essex M. Association between virus-specific T-cell responses and plasma viral load in human immunodeficiency virus type 1 subtype C infection. J Virol 2003; 77:882-90. [PMID: 12502804 PMCID: PMC140844 DOI: 10.1128/jvi.77.2.882-890.2003] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Virus-specific T-cell immune responses are important in restraint of human immunodeficiency virus type 1 (HIV-1) replication and control of disease. Plasma viral load is a key determinant of disease progression and infectiousness in HIV infection. Although HIV-1 subtype C (HIV-1C) is the predominant virus in the AIDS epidemic worldwide, the relationship between HIV-1C-specific T-cell immune responses and plasma viral load has not been elucidated. In the present study we address (i) the association between the level of plasma viral load and virus-specific immune responses to different HIV-1C proteins and their subregions and (ii) the specifics of correlation between plasma viral load and T-cell responses within the major histocompatibility complex (MHC) class I HLA supertypes. Virus-specific immune responses in the natural course of HIV-1C infection were analyzed in the gamma interferon (IFN-gamma)-enzyme-linked immunospot assay by using synthetic overlapping peptides corresponding to the HIV-1C consensus sequence. For Gag p24, a correlation was seen between better T-cell responses and lower plasma viral load. For Nef, an opposite trend was observed where a higher T-cell response was more likely to be associated with a higher viral load. At the level of the HLA supertypes, a lower viral load was associated with higher T-cell responses to Gag p24 within the HLA A2, A24, B27, and B58 supertypes, in contrast to the absence of such a correlation within the HLA B44 supertype. The present study demonstrated differential correlations (or trends to correlation) in various HIV-1C proteins, suggesting (i) an important role of the HIV-1C Gag p24-specific immune responses in control of viremia and (ii) more rapid viral escape from immune responses to Nef with no restraint of plasma viral load. Correlations between the level of IFN-gamma-secreting T cells and viral load within the MHC class I HLA supertypes should be considered in HIV vaccine design and efficacy trials.
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Affiliation(s)
- V Novitsky
- Harvard School of Public Health, Boston, Massachusetts 02115, USA
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145
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Wang B, Dyer WB, Zaunders JJ, Mikhail M, Sullivan JS, Williams L, Haddad DN, Harris G, Holt JAG, Cooper DA, Miranda-Saksena M, Boadle R, Kelleher AD, Saksena NK. Comprehensive analyses of a unique HIV-1-infected nonprogressor reveal a complex association of immunobiological mechanisms in the context of replication-incompetent infection. Virology 2002; 304:246-64. [PMID: 12504566 DOI: 10.1006/viro.2002.1706] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We recently demonstrated that a unique HIV-1-infected nonprogressor was infected with a nonevolving replication-incompetent HIV-1 strain, showing a total absence of viral evolution in vivo. Potent immune responses against HIV-1 were observed in his PBMC, despite an apparent lack of viral replication for at least 8 years. His PBMC resisted superinfection with CCR5, CXCR4, and dual-tropic HIV-1 strains, although highly purified CD4+ T cells supported infection, but without any visible cytopathic effect. Potent noncytolytic CD8+ T cell antiviral activity was shown to protect his PBMC from productive infection. This activity was not mediated by several known chemokines or IFN-gamma, which were produced at high levels after PHA activation of his CD8+ T cells, indicating the action of other CAF-like CD8 factors. This antiviral activity was a memory response, induced by HIV-specific stimulation to similar levels observed by PHA stimulation, but absent in ex vivo resting T cells. Immunological mechanisms associated with this antiviral suppressive activity included vigorous Gag-specific helper T cell proliferative responses and high-level IFN-gamma release by both CD4 and CD8 T cells. These responses were broadly directed against multiple Gag epitopes, both previously reported and some novel epitopes. Strong HIV-specific helper T cell function was also associated with strong neutralizing antibodies. Understanding how to induce these protective immune responses in other individuals could provide a major step forward in the design of effective immunotherapies or vaccines against HIV infection.
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Affiliation(s)
- Bin Wang
- Retroviral Genetics Laboratory, Centre for Virus Research, Westmead Millennium Institute, Westmead Hospital, University of Sydney, Westmead, New South Wales 2145, Australia
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146
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Thakar MR, Patke D, Lakhashe SK, Bhonge L, Kulkarni SV, Tripathy SP, Gupte N, Brookmeyer R, Quinn TC, Paranjape RS, Bollinger RC. Consistent subtype-specific anti-HIV type 1 T lymphocyte responses in Indian subjects recently infected with HIV type 1. AIDS Res Hum Retroviruses 2002; 18:1389-93. [PMID: 12487810 DOI: 10.1089/088922202320935465] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Anti-HIV-1-specific T cell responses in early HIV-1 infection have been found to be important in deciding the course of disease progression. But there are few data concerning nonsubtype B HIV infection. HIV-1 subtype C is the most prevalent subtype in India. HIV-1 Gag-specific T cell responses in 12 Indian subjects with recent HIV-1 infection were characterized by an ELISpot assay at two consecutive visits and their correlation with plasma viral load and CD4(+) T lymphocyte counts was studied. Ten of the 12 subjects demonstrated T cell responses to either one or both Gag B and C peptides, on at least one visit. Five of 10 responders showed a consistent response (response at both visits): 4 exhibited a Gag C-specific consistent response and 1 showed a consistent response to Gag B. The remaining five patients, showing response at only one of the two visits, were considered inconsistent responders. None of the individuals showed a consistent response to both B and C Gag peptides. Marginally significant correlation was observed between consistency of the response and lower plasma viral load (p = 0.062). The subtype-specific Gag C response was also found to be correlated with lower viral load as compared with the response to Gag B (r = -0.336, p = 0.054 for subtype C and r = -0.234, p = 0.13 for subtype B). The data suggest that the patients exhibiting consistent subtype-specific responses to HIV-1 Gag might have better control of viral replication in early HIV infection.
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147
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Chouquet C, Autran B, Gomard E, Bouley JM, Calvez V, Katlama C, Costagliola D, Rivière Y. Correlation between breadth of memory HIV-specific cytotoxic T cells, viral load and disease progression in HIV infection. AIDS 2002; 16:2399-407. [PMID: 12461413 DOI: 10.1097/00002030-200212060-00004] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Memory cytotoxic T lymphocytes (CTL) should play a key role in controlling HIV infection. The correlations between the breadth and specificities of memory CTL and virus production and disease progression are still unknown, but are of major importance for vaccine strategies. METHODS AND DESIGN One-hundred and forty-eight chronically-infected patients, enrolled before the advent of highly active antiretroviral therapy, were followed-up prospectively over 5 years. Memory CTL were tested in vitro against autologous target cells expressing Env, Gag, Pol, Nef, Vif, Rev or Tat HIV-LAI sequences. RESULTS At entry, an HIV-specific CTL response was detected against at least one viral protein in 77% cases, with Pol and Gag recognized in 57% each, Env and Nef in 36% and 30%, Vif, Rev and Tat in 14%, 10% and 5% of cases respectively. The same pattern was observed over time with some individual variations in responder status. Multivariate analysis of longitudinal data showed that the average number of recognized proteins of two at entry significantly decreased over time with the average loss of one protein per 7 years. The number of recognized proteins was negatively associated with viral load (P < 0.05), and with occurrence of opportunistic infection (P < 0.01), and significantly correlated with CD8 cell counts (P < 0.05) but not with CD4 cell counts. CONCLUSION The breadth of HIV antigens recognized by memory CTL is a major correlate of immune control of HIV-replication and disease progression.
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Affiliation(s)
- Cécile Chouquet
- INSERM EMI 0214, Laboratoire d'Immunologie Cellulaire et Tissulaire, Centre Hospitalier Pitié-Salpétrière, Institut Pasteur, 25 rue du Dr. Roux, 75015 Paris, France
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148
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van Baarle D, Kostense S, van Oers MHJ, Hamann D, Miedema F. Failing immune control as a result of impaired CD8+ T-cell maturation: CD27 might provide a clue. Trends Immunol 2002; 23:586-91. [PMID: 12464570 DOI: 10.1016/s1471-4906(02)02326-8] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Despite readily detectable virus-specific CD8(+) T cells in most HIV-infected patients, immune surveillance is eventually lost, leading to progression to AIDS. Recently developed insights into human T-cell differentiation have been used to study the phenotype of virus-specific T cells in HIV-infected individuals. Based on these results, we propose that failing immune control in human viral infection could be a result of impaired cytotoxic T-lymphocyte (CTL) maturation into fully differentiated effector T cells. Impaired maturation is not confined to HIV-specific CD8(+) T cells but could also be involved in failing immunity to Epstein-Barr virus and other viral infections. We postulate that CD27(-) effector CD8(+) T cells might be required for adequate control of chronic viral infection and prevention of disease development.
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Affiliation(s)
- Debbie van Baarle
- Dept of Clinical Viro-Immunology, Sanquin Research at CLB & Landsteiner Laboratory of the Academic Medical Center, University of Amsterdam, The Netherlands.
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149
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Abstract
The AIDS epidemic continues to advance, and the development of a preventive HIV vaccine has become a major objective for scientific research. An effective vaccine against this virus is not available and complete protection still has not been achieved in animal models. In this review the major challenges related to the development of a vaccine against HIV are analyzed, particularly the mechanisms involved in viral escape from the immune response, and the results obtained with the various therapeutic and preventive vaccine prototypes are summarized. Finally, the social, economic and health aspects related to research on HIV vaccines and the current controversy around the performance of clinical trials with these agents is discussed.
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Affiliation(s)
- José Alcami
- Unidad de Inmunopatología del SIDA. Centro Nacional de Microbiología. Instituto de Salud Carlos III. Madrid. España.
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150
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Jin X, Gao X, Ramanathan M, Deschenes GR, Nelson GW, O'Brien SJ, Goedert JJ, Ho DD, O'Brien TR, Carrington M. Human immunodeficiency virus type 1 (HIV-1)-specific CD8+-T-cell responses for groups of HIV-1-infected individuals with different HLA-B*35 genotypes. J Virol 2002; 76:12603-10. [PMID: 12438586 PMCID: PMC136673 DOI: 10.1128/jvi.76.24.12603-12610.2002] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2002] [Accepted: 08/29/2002] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1)-infected individuals with HLA-B*35 allelic variants B*3502/3503/3504/5301 (B*35-Px) progress more rapidly to AIDS than do those with B*3501 (B*35-PY). The mechanisms responsible for this phenomenon are not clear. To examine whether cellular immune responses may differ according to HLA-B*35 genotype, we quantified HIV-1-specific CD8(+)-T-cell (CTL) responses using an intracellular cytokine-staining assay with specimens from 32 HIV-1-positive individuals who have B*35 alleles. Among them, 75% had CTL responses to Pol, 69% had CTL responses to Gag, 50% had CTL responses to Nef, and 41% had CTL responses to Env. The overall magnitude of CTL responses did not differ between patients bearing B*35-Px genotypes and those bearing B*35-PY genotypes. A higher percentage of Gag-specific CTL was associated with lower HIV-1 RNA levels (P = 0.009) in individuals with B*35-PY. A negative association between CTL activity for each of the four HIV antigens and viral load was observed among individuals with B*35-PY, and the association reached significance for Gag. No significant relationship between CTL activity and viral load was observed in the B*35-Px group. The relationship between total CTL activity and HIV RNA among B*35-Px carriers differed significantly from that among B*35-PY carriers (P < 0.05). The data are consistent with the hypothesis that higher levels of virus-specific CTL contribute to protection against HIV disease progression in infected individuals with B*35-PY, but not in those with B*35-Px.
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Affiliation(s)
- Xia Jin
- Infectious Disease Unit, University of Rochester Medical Center, 601 Elmwood Avenue, Box 689, Rochester, NY 14642, USA.
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