Medicine and Health Sciences Commons^™

Dengue Virus Protein Recognition By Virus-Specific Murine Cd8+ Cytotoxic T Lymphocytes, Alan L. Rothman, Ichiro Kurane, Ching-Juh Lai, Michael Bray, Barry Falgout, Ruhe Men, Francis A. Ennis

Alan Rothman

The identification of the protein targets for dengue virus-specific T lymphocytes may be useful for planning the development of subunit vaccines against dengue. We studied the recognition by murine dengue virus-specific major histocompatibility complex class I-restricted, CD8+ cytotoxic T lymphocytes (CTL) of dengue virus proteins using recombinant vaccinia viruses containing segments of the dengue virus genome. CTL from H-2k mice recognized a single serotype-cross-reactive epitope on the nonstructural (NS) protein NS3. CTL from H-2b mice recognized a serotype-cross-reactive epitope that was localized to NS4a or NS4b. CTL from H-2d mice recognized at least three epitopes: a serotype-specific epitope on one …

Dengue Virus Nonstructural Protein Ns5 Induces Interleukin-8 Transcription And Secretion, Carey L. Medin, Katherine A. Fitzgerald, Alan L. Rothman

Alan Rothman

Elevated circulating levels of chemokines have been reported in patients with dengue fever and are proposed to contribute to the pathogenesis of dengue disease. To establish in vitro models for chemokine induction by dengue 2 virus (DEN2V), we studied a variety of human cell lines and primary cells. DEN2V infection of HepG2 and primary dendritic cells induced the production of interleukin-8 (IL-8), RANTES, MIP-1alpha, and MIP-1beta, whereas only IL-8 and RANTES were induced following dengue virus infection of HEK293 cells. Chemokine secretion was accompanied by an increase in steady-state mRNA levels. No chemokine induction was observed in HEK293 cells treated …

Cross-Reactivity And Expansion Of Dengue-Specific T Cells During Acute Primary And Secondary Infections In Humans, Heather L. Friberg-Robertson, Hema Sundara Bashyam, Tomoko Toyosaki-Maeda, James A. Potts, Thomas C. Greenough, Siripen Kalayanarooj, Robert V. Gibbons, Ananda Nisalak, Anon Srikiatkhachorn, Sharone Green, Henry A. F. Stephens, Alan L. Rothman, Anuja Mathew

Alan Rothman

Serotype-cross-reactive memory T cells responding to secondary dengue virus (DENV) infection are thought to contribute to disease. However, epitope-specific T cell responses have not been thoroughly compared between subjects with primary versus secondary DENV infection. We studied CD8(+) T cells specific for the HLA-A*1101-restricted NS3(133) epitope in a cohort of A11(+) DENV-infected patients throughout acute illness and convalescence. We compared the expansion, serotype-cross-reactivity, and activation of these cells in PBMC from patients experiencing primary or secondary infection and mild or severe disease by flow cytometry. Our results show expansion and activation of DENV-specific CD8(+) T cells during acute infection, which …

Analysis Of Murine Cd8(+) T-Cell Clones Specific For The Dengue Virus Ns3 Protein: Flavivirus Cross-Reactivity And Influence Of Infecting Serotype, Anne C. Spaulding, Ichiro Kurane, Francis A. Ennis, Alan L. Rothman

Alan Rothman

Serotype-cross-reactive dengue virus-specific cytotoxic T lymphocytes (CTL) induced during a primary dengue virus infection are thought to play a role in the immunopathogenesis of dengue hemorrhagic fever (DHF) during a secondary dengue virus infection. Although there is no animal model of DHF, we previously reported that murine dengue virus-specific CTL responses are qualitatively similar to human dengue virus-specific CTL responses. We used BALB/c mice to study the specificity of the CTL response to an immunodominant epitope on the dengue virus NS3 protein. We mapped the minimal H-2Kd-restricted CTL epitope to residues 298 to 306 of the dengue type 2 virus …

Dengue Virus Infection And Virus-Specific Hla-A2 Restricted Immune Responses In Humanized Nod-Scid Il2rgammanull Mice, Smita Jaiswal, Todd Pearson, Heather Friberg, Leonard D. Shultz, Dale L. Greiner, Alan L. Rothman, Anuja Mathew

Alan Rothman

BACKGROUND: The lack of a suitable animal model to study viral and immunological mechanisms of human dengue disease has been a deterrent to dengue research.

METHODOLOGY/PRINCIPAL FINDINGS: We sought to establish an animal model for dengue virus (DENV) infection and immunity using non-obese diabetic/severe combined immunodeficiency interleukin-2 receptor gamma-chain knockout (NOD-scid IL2rgamma(null)) mice engrafted with human hematopoietic stem cells. Human CD45(+) cells in the bone marrow of engrafted mice were susceptible to in vitro infection using low passage clinical and established strains of DENV. Engrafted mice were infected with DENV type 2 by different routes and at multiple time points …

A Comparative Study Of Leptospirosis And Dengue In Thai Children, Daniel H. Libraty, Khin S. A. Myint, Clinton K. Murray, Robert V. Gibbons, Mammen P. Mammen, Timothy P. Endy, Wenjun Li, David W. Vaughn, Ananda Nisalak, Siripen Kalayanarooj, Duane R. Hospenthal, Sharone Green, Alan L. Rothman, Francis A. Ennis

Alan Rothman

BACKGROUND: Leptospirosis is an emerging zoonosis that is often under-recognized in children and commonly confused with dengue in tropical settings. An enhanced ability to distinguish leptospirosis from dengue in children would guide clinicians and public health personnel in the appropriate use of limited healthcare resources. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a prospective, hospital-based, study of children with acute febrile illnesses and dengue in Thailand. Among the children without dengue, we identified those with leptospirosis using anti-leptospira IgM and microscopic agglutination titers in paired acute and convalescent blood samples. We then performed a case-control comparison of symptoms, signs, and clinical laboratory values …

Prediction Of Dengue Disease Severity Among Pediatric Thai Patients Using Early Clinical Laboratory Indicators, James A. Potts, Robert V. Gibbons, Alan L. Rothman, Anon Srikiatkhachorn, Stephen J. Thomas, Pra-On Supradish, Stephenie C. Lemon, Daniel H. Libraty, Sharone Green, Siripen Kalayanarooj

Alan Rothman

BACKGROUND: Dengue virus is endemic in tropical and sub-tropical resource-poor countries. Dengue illness can range from a nonspecific febrile illness to a severe disease, Dengue Shock Syndrome (DSS), in which patients develop circulatory failure. Earlier diagnosis of severe dengue illnesses would have a substantial impact on the allocation of health resources in endemic countries. METHODS AND FINDINGS: We compared clinical laboratory findings collected within 72 hours of fever onset from a prospective cohort children presenting to one of two hospitals (one urban and one rural) in Thailand. Classification and regression tree analysis was used to develop diagnostic algorithms using different …

Robust Intrapulmonary Cd8 T Cell Responses And Protection With An Attenuated N1l Deleted Vaccinia Virus, Anuja Mathew, Joel O'Bryan, William L. Marshall, Girish J. Kotwal, Masanori Terajima, Sharone Green, Alan L. Rothman, Francis A. Ennis

Alan Rothman

BACKGROUND: Vaccinia viruses have been used as a model for viral disease and as a protective live vaccine. METHODOLOGY AND PRINCIPAL FINDINGS: We investigated the immunogenicity of an attenuated strain of vaccinia virus engineered to inactivate the N1L gene (vGK5). Using the intranasal route, this recombinant virus was 2 logs less virulent compared to the wildtype VACV-WR. Infection by the intranasal, intraperitoneal, and tail scarification routes resulted in the robust induction of cytolytic virus-specific CD8 T cells in the spleens and the lungs. VACV-specific antibodies were also detected in the sera of mice infected 3-5 months prior with the attenuated …

Dengue Virus-Specific Murine T-Lymphocyte Proliferation: Serotype Specificity And Response To Recombinant Viral Proteins, Alan L. Rothman, Ichiro Kurane, Yi-Ming Zhang, Ching-Juh Lai, Francis A. Ennis

Alan Rothman

Definition of the T-lymphocyte responses to dengue viruses should aid in the development of safe and effective vaccines and help to explain the pathophysiology of dengue hemorrhagic fever and dengue shock syndrome. In this study, we demonstrated that dengue virus-specific T lymphocytes were detected in spleen cells from dengue virus-immune mice using an in vitro proliferation assay. Following immunization with a single dose of infectious dengue virus, murine lymphocytes showed increased proliferation when incubated in the presence of viral antigens of the same serotype but not in the presence of control antigens. Depletion experiments with antibody and complement showed that …