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Full-Text Articles in Medical Immunology

T-Cell Responses To Immunodominant Listeria Epitopes Limit Vaccine-Directed Responses To The Colorectal Cancer Antigen, Guanylyl Cyclase C, John C. Flickinger, Jagmohan Singh, Yanki Yarman, Robert D Carlson, Joshua Barton, Scott A Waldman, Adam E. Snook Mar 2022

T-Cell Responses To Immunodominant Listeria Epitopes Limit Vaccine-Directed Responses To The Colorectal Cancer Antigen, Guanylyl Cyclase C, John C. Flickinger, Jagmohan Singh, Yanki Yarman, Robert D Carlson, Joshua Barton, Scott A Waldman, Adam E. Snook

Department of Pharmacology and Experimental Therapeutics Faculty Papers

The Gram-positive bacterium Listeria monocytogenes (Lm) is an emerging platform for cancer immunotherapy. To date, over 30 clinical trials have been initiated testing Lm cancer vaccines across a wide variety of cancers, including lung, cervical, colorectal, and pancreatic. Here, we assessed the immunogenicity of an Lm vaccine against the colorectal tumor antigen GUCY2C (Lm-GUCY2C). Surprisingly, Lm-GUCY2C vaccination did not prime naïve GUCY2C-specific CD8+ T-cell responses towards the dominant H-2Kd-restricted epitope, GUCY2C254-262. However, Lm-GUCY2C produced robust CD8+ T-cell responses towards Lm-derived peptides suggesting that GUCY2C254-262 peptide may be subdominant to Lm-derived peptides. Indeed, incorporating immunogenic Lm peptides into an adenovirus-based GUCY2C …


The Great Debate At 'Immunotherapy Bridge', Naples, December 5, 2019., Paolo A Ascierto, Carlo Bifulco, Jerome Galon, Claus Garbe, Samir N Khleif, Jennifer Mcquade, Kunle Odunsi, Hideho Okada, Chrystal M Paulos, Sergio A Quezada, Hussein A Tawbi, John Timmerman, Giorgio Trinchieri, Lisa H Butterfield, Igor Puzanov Aug 2020

The Great Debate At 'Immunotherapy Bridge', Naples, December 5, 2019., Paolo A Ascierto, Carlo Bifulco, Jerome Galon, Claus Garbe, Samir N Khleif, Jennifer Mcquade, Kunle Odunsi, Hideho Okada, Chrystal M Paulos, Sergio A Quezada, Hussein A Tawbi, John Timmerman, Giorgio Trinchieri, Lisa H Butterfield, Igor Puzanov

Articles, Abstracts, and Reports

As part of the 2019 Immunotherapy Bridge congress (December 4-5, Naples, Italy), the Great Debate session featured counterpoint views from leading experts on six topical issues in immunotherapy today. These were the use of chimeric antigen receptor T cell therapy in solid tumors, whether the Immunoscore should be more widely used in clinical practice, whether antibody-dependent cellular cytotoxicity is important in the mode of action of anticytotoxic T-lymphocyte-associated protein 4 antibodies, whether the brain is immunologically unique or just another organ, the role of microbiome versus nutrition in affecting responses to immunotherapy, and whether chemotherapy is immunostimulatory or immunosuppressive. Discussion …


Insights From Immuno-Oncology: The Society For Immunotherapy Of Cancer Statement On Access To Il-6-Targeting Therapies For Covid-19., Paolo Antonio Ascierto, Bernard Fox, Walter Urba, Ana Carrizosa Anderson, Michael B Atkins, Ernest C Borden, Julie Brahmer, Lisa H Butterfield, Alessandra Cesano, Daniel Chen, Tanja De Gruijl, Robert O Dillman, Charles G Drake, Leisha A Emens, Thomas F Gajewski, James L Gulley, F Stephen Hodi, Patrick Hwu, David Kaufman, Howard Kaufman, Michael Lotze, Douglas G Mcneel, Kim Margolin, Francesco Marincola, Michael J Mastrangelo, Marcela V Maus, David R Parkinson, Pedro J Romero, Paul M Sondel, Stefani Spranger, Mario Sznol, George J Weiner, Jon M Wiggington, Jeffrey S Weber Apr 2020

Insights From Immuno-Oncology: The Society For Immunotherapy Of Cancer Statement On Access To Il-6-Targeting Therapies For Covid-19., Paolo Antonio Ascierto, Bernard Fox, Walter Urba, Ana Carrizosa Anderson, Michael B Atkins, Ernest C Borden, Julie Brahmer, Lisa H Butterfield, Alessandra Cesano, Daniel Chen, Tanja De Gruijl, Robert O Dillman, Charles G Drake, Leisha A Emens, Thomas F Gajewski, James L Gulley, F Stephen Hodi, Patrick Hwu, David Kaufman, Howard Kaufman, Michael Lotze, Douglas G Mcneel, Kim Margolin, Francesco Marincola, Michael J Mastrangelo, Marcela V Maus, David R Parkinson, Pedro J Romero, Paul M Sondel, Stefani Spranger, Mario Sznol, George J Weiner, Jon M Wiggington, Jeffrey S Weber

Department of Microbiology and Immunology Faculty Papers

No abstract provided.


Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman Dec 2013

Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman

Dartmouth Scholarship

Understanding the coordination between humoral and cellular immune responses may be the key to developing protective vaccines, and because genetic studies of long-term HIV-1 nonprogressors have associated specific HLA-B alleles with spontaneous control of viral replication, this subject group presents an opportunity to investigate relationships between arms of the adaptive immune system. Given evidence suggesting that cellular immunity may play a role in viral suppression, we sought to determine whether and how the humoral immune response might vary among controllers. Significantly, Fc-mediated antibody effector functions have likewise been associated with durable viral control. In this study, we compared the effector …


The Role Of Indoleamine 2,3-Dioxygenase In Lp-Bpm5 Murine Retroviral Disease Progression, Megan A. O'Connor, William R. Green May 2013

The Role Of Indoleamine 2,3-Dioxygenase In Lp-Bpm5 Murine Retroviral Disease Progression, Megan A. O'Connor, William R. Green

Dartmouth Scholarship

Indoleamine 2,3-dioxygenase (IDO) is an immunomodulatory intracellular enzyme involved in tryptophan degradation. IDO is induced during cancer and microbial infections by cytokines, ligation of co-stimulatory molecules and/or activation of pattern recognition receptors, ultimately leading to modulation of the immune response. LP-BM5 murine retroviral infection induces murine AIDS (MAIDS), which is characterized by profound and broad immunosuppression of T- and B-cell responses. Our lab has previously described multiple mechanisms regulating the development of immunodeficiency of LP-BM5-induced disease, including Programmed Death 1 (PD-1), IL-10, and T-regulatory (Treg) cells. Immunosuppressive roles of IDO have been demonstrated in other retroviral models, suggesting a possible …


Enhanced Phagocytic Activity Of Hiv-Specific Antibodies Correlates With Natural Production Of Immunoglobulins With Skewed Affinity For Fcγr2a And Fcγr2b, Margaret E. Ackerman, Anne-Sophie Dugast, Elizabeth G. Mcandrew, Stephen Tsoukas Mar 2013

Enhanced Phagocytic Activity Of Hiv-Specific Antibodies Correlates With Natural Production Of Immunoglobulins With Skewed Affinity For Fcγr2a And Fcγr2b, Margaret E. Ackerman, Anne-Sophie Dugast, Elizabeth G. Mcandrew, Stephen Tsoukas

Dartmouth Scholarship

While development of an HIV vaccine that can induce neutralizing antibodies remains a priority, decades of research have proven that this is a daunting task. However, accumulating evidence suggests that antibodies with the capacity to harness innate immunity may provide some protection. While significant research has focused on the cytolytic properties of antibodies in acquisition and control, less is known about the role of additional effector functions. In this study, we investigated antibody-dependent phagocytosis of HIV immune complexes, and we observed significant differences in the ability of antibodies from infected subjects to mediate this critical effector function. We observed both …


Il-4 Engagement Of The Type 1 Il-4 Receptor Complex Enhances Mouse Eosinophil Migration To Eotaxin-1 In Vitro, Nicola M. Heller, William M. Gwinn, Raymond P. Donnelly, Stephanie L. Constant, Achsah D. Keegan Jun 2012

Il-4 Engagement Of The Type 1 Il-4 Receptor Complex Enhances Mouse Eosinophil Migration To Eotaxin-1 In Vitro, Nicola M. Heller, William M. Gwinn, Raymond P. Donnelly, Stephanie L. Constant, Achsah D. Keegan

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Previous work from our laboratory demonstrated that IL-4Rα expression on a myeloid cell type was responsible for enhancement of Th2-driven eosinophilic inflammation in a mouse model of allergic lung inflammation. Subsequently, we have shown that IL-4 signaling through type I IL-4 receptors on monocytes/macrophages strongly induced activation of the IRS-2 pathway and a subset of genes characteristic of alternatively activated macrophages. The direct effect(s) of IL-4 and IL-13 on mouse eosinophils are not clear. The goal of this study was determine the effect of IL-4 and IL-13 on mouse eosinophil function.

Methods

Standard Transwell chemotaxis assay was used to …


Evidence That The Density Of Self Peptide-Mhc Ligands Regulates T-Cell Receptor Signaling., Nadia Anikeeva, Dimitry Gakamsky, Jørgen Schøller, Yuri Sykulev Jan 2012

Evidence That The Density Of Self Peptide-Mhc Ligands Regulates T-Cell Receptor Signaling., Nadia Anikeeva, Dimitry Gakamsky, Jørgen Schøller, Yuri Sykulev

Department of Microbiology and Immunology Faculty Papers

Noncognate or self peptide-MHC (pMHC) ligands productively interact with T-cell receptor (TCR) and are always in a large access over the cognate pMHC on the surface of antigen presenting cells. We assembled soluble cognate and noncognate pMHC class I (pMHC-I) ligands at designated ratios on various scaffolds into oligomers that mimic pMHC clustering and examined how multivalency and density of the pMHCs in model clusters influences the binding to live CD8 T cells and the kinetics of TCR signaling. Our data demonstrate that the density of self pMHC-I proteins promotes their interaction with CD8 co-receptor, which plays a critical role …


B1b Lymphocyte-Derived Antibodies Control Borrelia Hermsii Independent Of Fcα/Μ Receptor And In The Absence Of Host Cell Contact., Matthew J. Colombo, David Abraham, Akira Shibuya, Kishore R. Alugupalli Dec 2011

B1b Lymphocyte-Derived Antibodies Control Borrelia Hermsii Independent Of Fcα/Μ Receptor And In The Absence Of Host Cell Contact., Matthew J. Colombo, David Abraham, Akira Shibuya, Kishore R. Alugupalli

Department of Microbiology and Immunology Faculty Papers

The critical role of IgM in controlling pathogen burden has been demonstrated in a variety of infection models. In the murine model of Borrelia hermsii infection, IgM is necessary and sufficient for the rapid clearance of bacteremia. Convalescent, but not naïve, B1b cells generate a specific IgM response against B. hermsii, but the mechanism of IgM-mediated protection is unknown. Here, we show that neither Fcα/μR, a high-affinity receptor for IgM, nor IgM-dependent complement activation is required for controlling B. hermsii. Bacteria in diffusion chambers with a pore size impermeable to cells were killed when diffusion chambers were implanted into either …


In Vitro Migration Of Cytotoxic T Lymphocyte Derived From A Colon Carcinoma Patient Is Dependent On Ccl2 And Ccr2., Klara Berencsi, Pyapalli Rani, Tianqian Zhang, Laura Gross, Michael Mastrangelo, Neal J Meropol, Dorothee Herlyn, Rajasekharan Somasundaram Mar 2011

In Vitro Migration Of Cytotoxic T Lymphocyte Derived From A Colon Carcinoma Patient Is Dependent On Ccl2 And Ccr2., Klara Berencsi, Pyapalli Rani, Tianqian Zhang, Laura Gross, Michael Mastrangelo, Neal J Meropol, Dorothee Herlyn, Rajasekharan Somasundaram

Department of Medical Oncology Faculty Papers

BACKGROUND: Infiltration of colorectal carcinomas (CRC) with T-cells has been associated with good prognosis. There are some indications that chemokines could be involved in T-cell infiltration of tumors. Selective modulation of chemokine activity at the tumor site could attract immune cells resulting in tumor growth inhibition. In mouse tumor model systems, gene therapy with chemokines or administration of antibody (Ab)-chemokine fusion proteins have provided potent immune mediated tumor rejection which was mediated by infiltrating T cells at the tumor site. To develop such immunotherapeutic strategies for cancer patients, one must identify chemokines and their receptors involved in T-cell migration toward …


Uncoupling Scavenger Receptor A-Mediated Phagocytosis Of Bacteria From Endotoxic Shock Resistance, Eyal Amiel, Julie L. Acker, Ryan M. Collins, Brent Berwin Aug 2009

Uncoupling Scavenger Receptor A-Mediated Phagocytosis Of Bacteria From Endotoxic Shock Resistance, Eyal Amiel, Julie L. Acker, Ryan M. Collins, Brent Berwin

Dartmouth Scholarship

Unresolved infection by gram-negative bacteria can result in the potentially lethal condition known as endotoxic shock, whereby uncontrolled inflammation can lead to multiple organ failure and death of the infected host. Previous results have demonstrated that animals deficient in class A scavenger receptor (SRA), a trafficking receptor for bacteria and bacterium-derived molecules, are more susceptible to endotoxic shock. This has been proposed to be a result of impaired SRA-dependent phagocytic clearance of bacteria resulting in stronger proinflammatory stimuli. In this report, we test the hypothesis that there is an obligate reciprocal relationship between SRA-mediated phagocytosis of bacteria and susceptibility to …


Il-9 As A Mediator Of Th17-Driven Inflammatory Disease, Elizabeth C. Nowak, Casey T. Weaver, Henrietta Turner, Sakhina Begum-Haque, Burkhard Becher, Bettina Schreiner, Anthony J. Coyle, Lloyd H. Kasper, Randolph J. Noelle Jun 2009

Il-9 As A Mediator Of Th17-Driven Inflammatory Disease, Elizabeth C. Nowak, Casey T. Weaver, Henrietta Turner, Sakhina Begum-Haque, Burkhard Becher, Bettina Schreiner, Anthony J. Coyle, Lloyd H. Kasper, Randolph J. Noelle

Dartmouth Scholarship

We report that like other T cells cultured in the presence of transforming growth factor (TGF) beta, Th17 cells also produce interleukin (IL) 9. Th17 cells generated in vitro with IL-6 and TGF-beta as well as purified ex vivo Th17 cells both produced IL-9. To determine if IL-9 has functional consequences in Th17-mediated inflammatory disease, we evaluated the role of IL-9 in the development and progression of experimental autoimmune encephalomyelitis, a mouse model of multiple sclerosis. The data show that IL-9 neutralization and IL-9 receptor deficiency attenuates disease, and this correlates with decreases in Th17 cells and IL-6-producing macrophages in …


Ccl20/Macrophage Inflammatory Protein 3Α And Tumor Necrosis Factor Alpha Production By Primary Uterine Epithelial Cells In Response To Treatment With Lipopolysaccharide Or Pam3cys, M. A. Crane-Godreau, C. R. Wira Jan 2005

Ccl20/Macrophage Inflammatory Protein 3Α And Tumor Necrosis Factor Alpha Production By Primary Uterine Epithelial Cells In Response To Treatment With Lipopolysaccharide Or Pam3cys, M. A. Crane-Godreau, C. R. Wira

Dartmouth Scholarship

Having previously shown that CCL20/macrophage inflammatory protein 3 and tumor necrosis factor alpha (TNF-alpha) are released by polarized primary rat uterine epithelial cells (UEC) in response to Escherichia coli but not to Lactobacillus rhamnosus , we sought to determine if epithelial cells are responsive to pathogen-associated molecular patterns (PAMP), including lipopolysaccharide (LPS), lipoteichoic acid (LTA), and Pam 3 Cys, a bacterial lipoprotein analog. Epithelial cells were grown to confluence on Nunc cell culture inserts prior to apical treatment with PAMPs. In response to LPS, LTA, and Pam 3 Cys (EMC Microcollection GmbH, Tu ̈- bingen, Germany), CCL20 levels increased (4- …


Differential Expression Of Toll-Like Receptors 2 And 4 In Tissues Of The Human Female Reproductive Tract, Patricia A. Pioli, Eyal Amiel, Todd M. Schaefer, John E. Connolly, Charles R. Wira, Paul M. Guyre Oct 2004

Differential Expression Of Toll-Like Receptors 2 And 4 In Tissues Of The Human Female Reproductive Tract, Patricia A. Pioli, Eyal Amiel, Todd M. Schaefer, John E. Connolly, Charles R. Wira, Paul M. Guyre

Dartmouth Scholarship

Toll-like receptor (TLR) signal transduction is a central component of the innate immune response to pathogenic challenge. Although recent studies have begun to elucidate differences in acquired immunity in tissues of the human female reproductive tract, there is a relative paucity of work regarding innate defense mechanisms. We investigated TLR mRNA and protein expression in tissues of the human female reproductive tract. Constitutive mRNA expression of TLRs 1 to 6 was observed in fallopian tubes, uterine endometrium, cervix, and ectocervix. Furthermore, transcripts of the signaling adapter MyD88 and the accessory molecule CD14 were also detected in all tissues assayed. Quantitative …


Gitr Activation Induces An Opposite Effect On Alloreactive Cd4(+) And Cd8(+) T Cells In Graft-Versus-Host Disease., Stephanie J Muriglan, Teresa Ramirez-Montagut, Onder Alpdogan, Thomas W Van Huystee, Jeffrey M Eng, Vanessa M Hubbard, Adam A Kochman, Kartono H Tjoe, Carlo Riccardi, Pier Paolo Pandolfi, Shimon Sakaguchi, Alan N Houghton, Marcel R M Van Den Brink Jul 2004

Gitr Activation Induces An Opposite Effect On Alloreactive Cd4(+) And Cd8(+) T Cells In Graft-Versus-Host Disease., Stephanie J Muriglan, Teresa Ramirez-Montagut, Onder Alpdogan, Thomas W Van Huystee, Jeffrey M Eng, Vanessa M Hubbard, Adam A Kochman, Kartono H Tjoe, Carlo Riccardi, Pier Paolo Pandolfi, Shimon Sakaguchi, Alan N Houghton, Marcel R M Van Den Brink

Department of Medical Oncology Faculty Papers

Glucocorticoid-induced tumor necrosis factor receptor family-related gene (GITR) is a member of the tumor necrosis factor receptor (TNFR) family that is expressed at low levels on unstimulated T cells, B cells, and macrophages. Upon activation, CD4(+) and CD8(+) T cells up-regulate GITR expression, whereas immunoregulatory T cells constitutively express high levels of GITR. Here, we show that GITR may regulate alloreactive responses during graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT). Using a BMT model with major histocompatibility complex class I and class II disparity, we demonstrate that GITR stimulation in vitro and in vivo enhances alloreactive CD8(+)CD25(-) T …


Combined Tlr And Cd40 Triggering Induces Potent Cd8+ T Cell Expansion With Variable Dependence On Type I Ifn, Cory L. Ahonen, Christie L. Doxsee, Sean M. M. Mcgurran, Tony R. Riter, William F. Wade, Richard J. Barth, John P. Vasilakos, Randolph J. Noelle, Ross M. Kedl Mar 2004

Combined Tlr And Cd40 Triggering Induces Potent Cd8+ T Cell Expansion With Variable Dependence On Type I Ifn, Cory L. Ahonen, Christie L. Doxsee, Sean M. M. Mcgurran, Tony R. Riter, William F. Wade, Richard J. Barth, John P. Vasilakos, Randolph J. Noelle, Ross M. Kedl

Dartmouth Scholarship

Toll-like receptors are important in the activation of innate immunity, and CD40 is a molecule critical for many T and B cell responses. Whereas agonists for either pathway have been used as vaccine adjuvants, we show that a combination of Toll-like receptor (TLR)7 and CD40 agonists synergize to stimulate CD8+ T cell responses 10–20-fold greater than the use of either agonist alone. Antigen-specific CD8+ T cells elicited from combination CD40/TLR7 treatment demonstrated both lytic activities and interferon (IFN)γ production and an enhanced secondary response to antigenic challenge. Agonists for TLRs 2/6, 3, 4, and 9 also synergized with …


Il-7 Enhances Peripheral T Cell Reconstitution After Allogeneic Hematopoietic Stem Cell Transplantation., Onder Alpdogan, Stephanie J Muriglan, Jeffrey M Eng, Lucy M Willis, Andrew S Greenberg, Barry J Kappel, Marcel R M Van Den Brink Oct 2003

Il-7 Enhances Peripheral T Cell Reconstitution After Allogeneic Hematopoietic Stem Cell Transplantation., Onder Alpdogan, Stephanie J Muriglan, Jeffrey M Eng, Lucy M Willis, Andrew S Greenberg, Barry J Kappel, Marcel R M Van Den Brink

Department of Medical Oncology Faculty Papers

We used clinically relevant murine allogeneic bone marrow transplantation (BMT) models to study the mechanisms by which IL-7 administration can improve posttransplant peripheral T cell reconstitution. After transplant we could distinguish two populations of mature donor T cells: (a) alloreactive T cells with decreased expression of CD127 (IL-7 receptor alpha chain) and (b) nonalloreactive T cells, which express CD127 and undergo homeostatic proliferation. IL-7 administration increased the homeostatic proliferation of nonalloreactive T cells, but had no effect on alloreactive T cells and the development of graft-versus-host disease. Allogeneic transplant of purified hematopoietic stem cells and adoptive transfer of thymocytes into …


A Genetic Lesion That Arrests Plasma Cell Homing To The Bone Marrow, Loren D. Erickson, Ling-Li Lin, Biyan Duan, Laurence Morel, Randolph J. Noelle Jan 2003

A Genetic Lesion That Arrests Plasma Cell Homing To The Bone Marrow, Loren D. Erickson, Ling-Li Lin, Biyan Duan, Laurence Morel, Randolph J. Noelle

Dartmouth Scholarship

The coordinated regulation of chemokine responsiveness plays a critical role in the development of humoral immunity. After antigen challenge and B cell activation, the emerging plasma cells (PCs) undergo CXCL12-induced chemotaxis to the bone marrow, where they produce Ab and persist. Here we show that PCs, but not B cells or T cells from lupus-prone NZM mice, are deficient in CXCL12-induced migration. PC unresponsiveness to CXCL12 results in a marked accumulation of PCs in the spleen of mice, and a concordant decrease in bone marrow PCs. Unlike normal mice, in NZM mice, a majority of the splenic PCs are long-lived. …


Treatment With Soluble Interleukin-15ralpha Exacerbates Intracellular Parasitic Infection By Blocking The Development Of Memory Cd8+ T Cell Response, Imtiaz A. Khan, Magali Moretto, Xiao-Qing Wei, Martha Williams, Joseph D. Schwartzman, F Y. Liew Jun 2002

Treatment With Soluble Interleukin-15ralpha Exacerbates Intracellular Parasitic Infection By Blocking The Development Of Memory Cd8+ T Cell Response, Imtiaz A. Khan, Magali Moretto, Xiao-Qing Wei, Martha Williams, Joseph D. Schwartzman, F Y. Liew

Dartmouth Scholarship

Interferon (IFN)-γ–producing CD8+ T cells are important for the successful resolution of the obligate intracellular parasite Toxoplasma gondii by preventing the reactivation or controlling a repeat infection. Previous reports from our laboratory have shown that exogenous interleukin (IL)-15 treatment augments the CD8+ T cell response against the parasite. However, the role of endogenous IL-15 in the proliferation of activated/memory CD8+ T cells during toxoplasma or any other infection is unknown. In this study, we treated T. gondii immune mice with soluble IL-15 receptor α (sIL-15Rα) to block the host endogenous IL-15. The treatment markedly reduced the ability …


Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper Jul 1994

Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper

Dartmouth Scholarship

Depression of the cellular immune response to Toxoplasma gondii has been reported in both mice and humans. The present study was undertaken to determine the kinetics and mechanism of the observed downregulation of interleukin 2 (IL-2) production during experimental murine toxoplasmosis. For these investigations, the cell-mediated immune response to the wild type (PTg) was compared with that to the less-virulent mutant parasite (PTgB), which is deficient in the major surface antigen, p30 (SAG-1). Spleen cells from infected A/J mice failed to proliferate in response to Toxoplasma antigens during the first week of infection. Both PTg- and PTgB-infected A/J mice exhibited …


Comparison Of Cytotoxic Properties Of Neonatal And Adult Neutrophils And Monocytes And Enhancement By Cytokines., E . R. Stiehm, R. L. Roberts, B. J. Ank, S. Plaeger-Marshall, N. Salman, L. Shen, M. W. Fanger May 1994

Comparison Of Cytotoxic Properties Of Neonatal And Adult Neutrophils And Monocytes And Enhancement By Cytokines., E . R. Stiehm, R. L. Roberts, B. J. Ank, S. Plaeger-Marshall, N. Salman, L. Shen, M. W. Fanger

Dartmouth Scholarship

We studied cytotoxic capabilities of newborn polymorphonuclear leukocytes (PMNs) and monocytes and their enhancement by cytokines and antibodies. Umbilical cord PMNs were assessed for their ability to kill various target cells spontaneously, after activation with phorbol myristate acetate, in the presence of antiserum (antibody-dependent cellular cytotoxicity), and in the presence of dually specific antibody (heteroantibody-mediated cytotoxicity). Target cells included the K562 cell line (natural killer cell target), chicken erythrocytes (CRBCs), and herpes simplex virus-infected CEM cell lines. Newborn PMNs were equivalent to adult PMNs in their cytotoxic capacity in several cytotoxicity assays. Neither adult nor newborn PMNs lyse tumor cell …


A Phorbol Ester Response Element Within The Human T-Cell Receptor Beta-Chain Enhancer., Haydn M. Prosser, David Wotton, Anne Gegonne, Jacques Ghysdael, Shuwen Wang, Nancy A. Speck, Michael J. Owen Oct 1992

A Phorbol Ester Response Element Within The Human T-Cell Receptor Beta-Chain Enhancer., Haydn M. Prosser, David Wotton, Anne Gegonne, Jacques Ghysdael, Shuwen Wang, Nancy A. Speck, Michael J. Owen

Dartmouth Scholarship

The activity of the T-cell receptor beta-chain gene enhancer is increased by activators of the protein kinase C pathway during T-cell activation. Analysis of mutant enhancer constructs identified two elements, beta E2 and beta E3, conferring phorbol ester inducibility. Multimerized beta E2 acted in isolation as a phorbol ester-responsive element. Both beta E2 and beta E3, which contain a consensus Ets-binding site, were shown to bind directly to the product of the c-ets-1 protooncogene. Both regions also bound a second factor, core-binding factor. Mutation of the beta E2 Ets site abolished the inducibility of the beta E2 multimer. beta E2 …


Camp Antagonizes Interleukin 2-Promoted T-Cell Cycle Progression At A Discrete Point In Early G1., Kirk W. Johnson, Bruce H. Davis, Kendall A. Smith Aug 1988

Camp Antagonizes Interleukin 2-Promoted T-Cell Cycle Progression At A Discrete Point In Early G1., Kirk W. Johnson, Bruce H. Davis, Kendall A. Smith

Dartmouth Scholarship

T lymphocytes are stimulated to proliferate in an autocrine/paracrine manner by the lymphokine interleukin 2 (IL-2). In seeking further insight into the mechanisms by which IL-2 induces progression of T cells through the G1 phase of the cell cycle, studies were performed with agents that increase cellular adenosine 3',5'-cyclic monophosphate (cAMP), a well-known inhibitor of lymphocyte growth. The addition of dibutyryl-cAMP, cholera toxin, forskolin, or 3-isobutyl-1-methylxanthine to an IL-2-dependent murine T-cell line evoked a dose-related suppression of S-phase transition without affecting cellular viability. Moreover, elevation of cAMP levels led to an accumulation of uniformly small cells, suggesting an arrest in …


Interleukin 2 Regulates Its Own Receptors., Kendall A. Smith, Doreen A. Cantrell Feb 1985

Interleukin 2 Regulates Its Own Receptors., Kendall A. Smith, Doreen A. Cantrell

Dartmouth Scholarship

The cell surface density of high-affinity membrane receptors for the T-lymphocytotrophic hormone interleukin 2 (IL-2) determines the rate of T-cell-cycle progression. Since 10-fold greater numbers of IL-2 receptor molecules were found by using a radiolabeled monoclonal antibody reactive with IL-2 receptors (anti-Tac) compared with binding of IL-2, the functional relationship of the binding sites recognized by both of these ligands was assessed. In the presence of cycloheximide, IL-2 binding sites declined with a half-time (t1/2) of 2.6 hr, whereas the decay of anti-Tac binding sites was much slower (t 1/2 = 6.4 hr). Moreover, after limited membrane proteolysis, the half-time …


Triggering Of The T3-Ti Antigen-Receptor Complex Results In Clonal T-Cell Proliferation Through An Interleukin 2-Dependent Autocrine Pathway., Stefan C. Meuer, Rebecca E. Hussey, Doreen A. Cantrell, James C. Hodgdon, Stuart F. Schlossman, Kendall A. Smith, Ellis L. Reinherz Mar 1984

Triggering Of The T3-Ti Antigen-Receptor Complex Results In Clonal T-Cell Proliferation Through An Interleukin 2-Dependent Autocrine Pathway., Stefan C. Meuer, Rebecca E. Hussey, Doreen A. Cantrell, James C. Hodgdon, Stuart F. Schlossman, Kendall A. Smith, Ellis L. Reinherz

Dartmouth Scholarship

Human T-cell clones and anti-T-cell-receptor antibodies (clonotypic) directed at surface receptors for antigen (T3-Ti molecular complex) as well as anti-interleukin 2 (IL-2) and anti-IL-2-receptor antibodies were utilized to investigate the mechanism by which alloantigens or antigen plus self-major histocompatibility complex (MHC) (i.e., physiologic ligand) trigger specific clonal proliferation. Soluble or Sepharose-bound anti-Ti monoclonal antibodies, like physiologic ligand, enhanced proliferative responses to purified IL-2 by inducing a 6-fold increase in surface IL-2 receptor expression. In contrast, only Sepharose-bound anti-Ti or physiologic ligand triggered endogenous clonal IL-2 production and resulted in subsequent proliferation. The latter was blocked by antibodies directed at either …


Rat Dendritic Cells Function As Accessory Cells And Control The Production Of A Soluble Factor Required For Mitogenic Responses Of T Lymphocytes., Wolfgang E. Klinkert, Jon H. Labadie, James P. O'Brien, Carl F. Beyer, William E. Bowers Sep 1980

Rat Dendritic Cells Function As Accessory Cells And Control The Production Of A Soluble Factor Required For Mitogenic Responses Of T Lymphocytes., Wolfgang E. Klinkert, Jon H. Labadie, James P. O'Brien, Carl F. Beyer, William E. Bowers

Dartmouth Scholarship

Transformation of T lymphocytes, induced by treatment with periodate or with neuraminidase plus galactose oxidase, requires the participation of accessory cells. Procedures were developed for the fractionation of rat lymph node cells, by which most of the lymphocytes can be recovered as a major population of cells that do not respond to mitogenic stimulation unless accessory cells from a separated minor population are added. Further purification led to a 1000-fold overall increase in accessory activity per cell, with a 50-70% yield. The purest preparations were virtually free of macrophages and contained more than 90% typical dendritic cells. Maximum responses occurred …