Life Sciences Commons^™

Hla Class I Supertype Associations With Clinical Outcome Of Secondary Dengue Virus Infections In Ethnic Thais, Sasijit Vejbaesya, Rungrot Thongpradit, Siripen Kalayanarooj, Komon Luangtrakool, Panpimon Luangtrakool, Robert V. Gibbons, Duangporn Srinak, Somporn Ngammthaworn, Kusuma Apisawes, In-Kyu Yoon, Stephen J. Thomas, Richard G. Jarman, Anon Srikiatkhachorn, Sharone Green, Dasnayanee Chandanayingyong, Sangshin Park, Jennifer Friedman, Alan L. Rothman, Henry A.F. Stephens

Sharone Green

BACKGROUND: Human leukocyte antigen (HLA) supertypes are groups of functionally related alleles that present structurally similar antigens to the immune system.

OBJECTIVES: To analyze HLA class I supertype associations with clinical outcome in hospitalized Thai children with acute dengue illness.

METHODS: Seven hundred sixty-two patients and population-matched controls recruited predominantly in Bangkok were HLA-A and -B typed. HLA supertype frequencies were compared and tested for significant dengue disease associations using logistic regression analyses. Multivariable models were built by conducting forward stepwise selection procedures.

RESULTS: In the final logistic regression model, the HLA-B44 supertype was protective against dengue hemorrhagic fever (DHF) …

Impaired T Cell Proliferation In Acute Dengue Infection, Anuja Mathew, Ichiro Kurane, Sharone Green, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Francis Ennis, Alan Rothman

Sharone Green

Decreased proliferative responses to mitogens and recall Ags have been observed in PBMC obtained during several acute human viral infections. To determine whether cell-mediated responses are altered during acute dengue infection, we examined the proliferative responses of PBMC from children enrolled in a prospective study of dengue infections in Thailand. All responses of PBMC during acute illness were compared with the same patients' PBMC obtained at least 6 mo after their infection. Proliferative responses to PHA, anti-CD3, tetanus toxoid, and dengue Ags were decreased significantly in PBMC obtained during the acute infection. The proliferative responses to PHA were restored by …

Development Of Antigen-Specific Memory Cd8+ T Cells Following Live-Attenuated Chimeric West Nile Virus Vaccination, Heidi Smith, Thomas Monath, Pamela Pazoles, Alan Rothman, Diane Casey, Masanori Terajima, Francis Ennis, Farshad Guirakhoo, Sharone Green

Sharone Green

ChimeriVax-WN02 is a novel live-attenuated West Nile virus (WNV) vaccine containing modified WNV premembrane (prM) and envelope (E) sequences inserted into the yellow fever 17D vaccine genome. We investigated the induction and evolution of CD8(+) T cell responses to a WNV envelope epitope, which is a dominant target in naturally infected HLA-A*02-positive individuals. WNV epitope-specific CD8(+) T cells were detected by HLA tetramer staining in 22 of 23 donors tested, with peak frequencies occurring between days 14 and 28. WNV epitope-specific T cells evolved from an effector phenotype to a long-lived memory phenotype. In the majority of donors, CD8(+) T …

T Cell Responses To An Hla-B*07-Restricted Epitope On The Dengue Ns3 Protein Correlate With Disease Severity, Iva Zivna, Sharone Green, David Vaughn, Siripen Kalayanarooj, Henry Stephens, Dasnayanee Chandanayingyong, Ananda Nisalak, Francis Ennis, Alan Rothman

Sharone Green

Dengue hemorrhagic fever (DHF), the severe manifestation of dengue virus (DV) infection characterized by plasma leakage, is more common in secondary DV infections in previously infected individuals and is associated with high levels of immune activation. To determine the Ag specificity of this immune response, we studied the response to an HLA-B*07-restricted T cell epitope, residues 221-232 of the DV NS3 protein, in 10 HLA-B*07(+) Thai children who were studied during and after acute DV infections. Peptide-specific T cells were detected in 9 of 10 subjects. The frequency of peptide-specific T cells was higher in subjects who had experienced DHF …

Predominance Of Hla-Restricted Cytotoxic T-Lymphocyte Responses To Serotype-Cross-Reactive Epitopes On Nonstructural Proteins Following Natural Secondary Dengue Virus Infection, Anuja Mathew, Ichiro Kurane, Sharone Green, Henry Stephens, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Dasnayanee Chandanayingyong, Francis Ennis, Alan Rothman

Sharone Green

We examined the memory cytotoxic T-lymphocytic (CTL) responses of peripheral blood mononuclear cells (PBMC) obtained from patients in Thailand 12 months after natural symptomatic secondary dengue virus infection. In all four patients analyzed, CTLs were detected in bulk culture PBMC against nonstructural dengue virus proteins. Numerous CD4+ and CD8+ CTL lines were generated from the bulk cultures of two patients, KPP94-037 and KPP94-024, which were specific for NS1.2a (NS1 and NS2a collectively) and NS3 proteins, respectively. All CTL lines derived from both patients were cross-reactive with other serotypes of dengue virus. The CD8+ NS1.2a-specific lines from patient KPP94-037 were HLA …

B-Cell Responses During Primary And Secondary Dengue Virus Infections In Humans, Anuja Mathew, Kim West, Siripen Kalayanarooj, Robert Gibbons, Anon Srikiatkhachorn, Sharone Green, Daniel Libraty, Smita Jaiswal, Alan Rothman

Sharone Green

Low-avidity serotype-cross-reactive antibodies are hypothesized to play a key role in triggering severe disease in patients with secondary dengue virus (DENV) infection. However, there is little systematic information about the frequency, avidity, and cross-reactivity of DENV-specific B cells in individuals experiencing primary instead of secondary infection. We compared DENV-specific B-cell responses in a cohort of Thai children with primary or secondary DENV infection. B cells specific for DENV precursor membrane protein, envelope (E) protein, and nonstructural protein 1 were detectable in immune peripheral blood mononuclear cells with the highest frequencies of DENV E-specific B cells detected in patients experiencing primary …

Immunopathologic Mechanisms Of Dengue Hemorrhagic Fever And Dengue Shock Syndrome, Ichiro Kurane, Alan Rothman, Peter Livingston, Sharone Green, Susan Gagnon, Jurand Janus, Bruce Innis, Suchitra Nimmannitya, Ananda Nisalak, Francis Ennis

Sharone Green

Dengue virus infections are a major cause of morbidity and mortality in tropical and subtropical areas of the world. The immunopathological mechanisms that result in severe complications of dengue virus infection, i.e. dengue hemorrhagic fever (DHF), are important to determine. Primary dengue virus infections induce serotype-specific and serotype-cross-reactive, CD4+ and CD8+ memory cytotoxic T lymphocytes (CTL). In secondary infections with a virus of a different serotype from that which caused primary infections, the presence of cross-reactive non-neutralizing antibodies results in an increased number of infected monocytes by dengue virus--antibody complexes. This in turn results in marked activation of serotype cross-reactive …

Dengue Virus-Reactive Cd8+ T Cells Display Quantitative And Qualitative Differences In Their Response To Variant Epitopes Of Heterologous Viral Serotypes, Hema Bashyam, Sharone Green, Alan Rothman

Sharone Green

Reactivation of serotype cross-reactive CD8+ memory T lymphocytes is thought to contribute to the immunopathogenesis of dengue disease during secondary infection by a heterologous serotype. Using cytokine flow cytometry, we have defined four novel HLA-A*02-restricted dengue viral epitopes recognized by up to 1.5% of circulating CD8+ T cells in four donors after primary vaccination. All four donors had the highest cytokine response to the epitope NS4b 2353. We also studied the effect of sequence differences in heterologous dengue serotypes on dengue-reactive CD8+ memory T cell cytokine and proliferative responses. The D3 variant of a different NS4b epitope 2423 and the …

Long Term Recall Of Memory Cd8 T Cells In Mice To First And Third Generation Smallpox Vaccines, Sharone Green, Francis Ennis, Anuja Mathew

Sharone Green

Since long-term immunity is a critical component of any effective vaccine, we compared over a 15-month period, the strength, durability and specificity of immunity of an attenuated smallpox vaccine Modified Vaccinia Ankara (MVA) to the New York City Board of Health (NYCBH) vaccine. The frequencies of CD8(+) T cells to an immunodominant CD8 T cell epitope B8R(20-27) remained remarkably stable in mice given either MVA or NYCBH. Both groups were also protected from a lethal intranasal challenge with Western Reserve strain of vaccinia virus (VACV-WR). Cytokine responses to virus-specific peptides were detectable with significant boosting upon challenge. Expression of most …

Cytokine Gene Expression And Protein Production In Peripheral Blood Mononuclear Cells Of Children With Acute Dengue Virus Infections, Susan Gagnon, Masuko Mori, Ichiro Kurane, Sharone Green, David Vaughn, Siripen Kalayanarooj, Saroj Suntayakorn, Francis Ennis, Alan Rothman

Sharone Green

Plasma leakage in dengue hemorrhagic fever (DHF) is associated with elevated plasma levels of cytokines. To define further the contribution of immune activation to DHF and the source of cytokines, we analyzed the production of cytokines in peripheral blood mononuclear cells (PBMC) obtained from children with dengue, using RT-PCR and immunostaining. Tumor necrosis factor-alpha (TNF-alpha) and TNF-beta expression was detected in all samples by PCR and in < 50% of samples by immunostaining. Interferon-gamma (IFN-gamma) expression was detected in < 50% of samples by either method. Interleukin-2 (IL-2) and IL-4 expression was detected in a few samples by immunostaining but was not …

Altered Effector Functions Of Virus-Specific And Virus Cross-Reactive Cd8+ T Cells In Mice Immunized With Related Flaviviruses., Derek Trobaugh, Liyan Yang, Francis Ennis, Sharone Green

Sharone Green

Memory cross-reactive CD8+ T-cell responses may induce protection or immunopathology upon secondary viral challenge. To elucidate the potential role of T cells in sequential flavivirus infection, we characterized cross-reactive CD4+ and CD8+ T-cell responses between attenuated and pathogenic Japanese encephalitis virus (JEV) and pathogenic West Nile virus (WNV). A previously reported WNV NS4b CD8+ T-cell epitope and its JEV variant elicited CD8+ T-cell responses in both JEV- and WNV-infected mice. The peptide variant homologous to the immunizing virus induced greater cytokine secretion and activated higher frequencies of epitope-specific CD8+ T cells. However, there was a virus-dependent, peptide variant-independent pattern of …

Identification Of Murine Poxvirus-Specific Cd8+ Ctl Epitopes With Distinct Functional Profiles, Anuja Mathew, Masanori Terajima, Kim West, Sharone Green, Alan Rothman, Francis Ennis, Jeffrey Kennedy

Sharone Green

Murine T cell epitopes against vaccinia virus (VV) have not been characterized to date in part due to the large and complex genome of VV. We have identified and characterized two CD8+ T cell epitopes on the A47L (modified VV Ankara strain (MVA)-029) and J6R (MVA-043) proteins of VV that are Db and Kb restricted, respectively. Following i.p. immunization with VV New York City Board of Health (NYCBH) strain, MVA-029 peptide-stimulated splenocytes secreted IFN-gamma from 7 days to 7 mo postimmunization, and virus-stimulated effectors were also able to lyse MVA-029-pulsed target cells at the same time points. In contrast, MVA-043 …

The Safety And Tolerability Of An Hiv-1 Dna Prime-Protein Boost Vaccine (Dp6-001) In Healthy Adult Volunteers, Jeffrey Kennedy, Mary Co, Sharone Green, Karen Longtine, Jaclyn Longtine, Melissa O'Neill, Janice Adams, Alan Rothman, Qiao Yu, Renita Johnson-Leva, Ranajit Pal, Shixia Wang, Shan Lu, Phillip Markham

Sharone Green

This report describes the safety observations following administration of a polyvalent DNA prime-protein boost HIV-1 vaccine formulated with adjuvant QS21. Local injection site reactions were the most common (65% of subjects), and included type IV delayed-type hypersensitivity (DTH) reactions at prior DNA inoculation sites in 12 of 28 (43%) subjects following protein vaccination. Systemic reactions revealed two cases of vasculitis temporally related to inoculation with recombinant Env protein+QS21 adjuvant. Questions remain regarding the cause of the vasculitis, but the unique DTH observation may have contributed to the high level of immune responses previously reported for this vaccine.

Cross-Subtype Antibody And Cellular Immune Responses Induced By A Polyvalent Dna Prime-Protein Boost Hiv-1 Vaccine In Healthy Human Volunteers, Shixia Wang, Jeffrey Kennedy, Kim West, David Montefiori, Scott Coley, John Lawrence, Siyuan Shen, Sharone Green, Alan Rothman, Francis Ennis, James Arthos, Ranajit Pal, Phillip Markham, Shan Lu

Sharone Green

An optimally effective AIDS vaccine would likely require the induction of both neutralizing antibody and cell-mediated immune responses, which has proven difficult to obtain in previous clinical trials. Here we report on the induction of Human Immunodeficiency Virus Type-1 (HIV-1)-specific immune responses in healthy adult volunteers that received the multi-gene, polyvalent, DNA prime-protein boost HIV-1 vaccine formulation, DP6-001, in a Phase I clinical trial conducted in healthy adult volunteers of both genders. Robust cross-subtype HIV-1-specific T cell responses were detected in IFNgamma ELISPOT assays. Furthermore, we detected high titer serum antibody responses that recognized a wide range of primary HIV-1 …

Persistence Of Virus-Specific Immune Responses In The Central Nervous System Of Mice After West Nile Virus Infection, Barbara Stewart, Valerie Demarest, Susan Wong, Sharone Green, Kristen Bernard

Sharone Green

BACKGROUND: West Nile virus (WNV) persists in humans and several animal models. We previously demonstrated that WNV persists in the central nervous system (CNS) of mice for up to 6 months post-inoculation. We hypothesized that the CNS immune response is ineffective in clearing the virus. RESULTS: Immunocompetent, adult mice were inoculated subcutaneously with WNV, and the CNS immune response was examined at 1, 2, 4, 8, 12 and 16 weeks post-inoculation (wpi). Characterization of lymphocyte phenotypes in the CNS revealed elevation of CD19+ B cells for 4 wpi, CD138 plasma cells at 12 wpi, and CD4+ and CD8+ T cells …