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Full-Text Articles in Medicine and Health Sciences
Parasite Manipulation Of The Invariant Chain And The Peptide Editor H2-Dm Affects Major Histocompatibility Complex Class Ii Antigen Presentation During Toxoplasma Gondii Infection, Louis-Philippe Leroux, Manami Nishi, Sandy El-Hage, Barbara A. Fox, David I Bzik, Florence Dzierszinsk
Parasite Manipulation Of The Invariant Chain And The Peptide Editor H2-Dm Affects Major Histocompatibility Complex Class Ii Antigen Presentation During Toxoplasma Gondii Infection, Louis-Philippe Leroux, Manami Nishi, Sandy El-Hage, Barbara A. Fox, David I Bzik, Florence Dzierszinsk
Dartmouth Scholarship
Toxoplasma gondii is an obligate intracellular protozoan parasite. This apicomplexan is the causative agent of toxoplasmosis, a leading cause of central nervous system disease in AIDS. It has long been known that T. gondii interferes with major histocompatibility complex class II (MHC-II) antigen presentation to attenuate CD4(+) T cell responses and establish persisting infections. Transcriptional downregulation of MHC-II genes by T. gondii was previously established, but the precise mechanisms inhibiting MHC-II function are currently unknown. Here, we show that, in addition to transcriptional regulation of MHC-II, the parasite modulates the expression of key components of the MHC-II antigen presentation pathway, …
Corneal Replication Is An Interferon Response-Independent Bottleneck For Virulence Of Herpes Simplex Virus 1 In The Absence Of Virion Host Shutoff, Tracy J. Pasieka, Vineet D. Menachery, Pamela C. Rosato, David A. Leib
Corneal Replication Is An Interferon Response-Independent Bottleneck For Virulence Of Herpes Simplex Virus 1 In The Absence Of Virion Host Shutoff, Tracy J. Pasieka, Vineet D. Menachery, Pamela C. Rosato, David A. Leib
Dartmouth Scholarship
Herpes simplex viruses lacking the virion host shutoff function (Δvhs) are avirulent and hypersensitive to type I and type II interferon (IFN). In this study, we demonstrate that even in the absence of IFN responses in AG129 (IFN-αβγR−/−) mice, Δvhs remains highly attenuated via corneal infection but is fully virulent via intracranial infection. The data demonstrate that the interferon-independent inherent replication defect of Δvhs has a significant impact upon peripheral replication and neuroinvasion.
Alpha-Defensins 1-3 Release By Dendritic Cells Is Reduced By Estrogen, Maria M. Escribese, Marta Rodríguez-García, Rhoda Sperling, Stephanie M. Engel
Alpha-Defensins 1-3 Release By Dendritic Cells Is Reduced By Estrogen, Maria M. Escribese, Marta Rodríguez-García, Rhoda Sperling, Stephanie M. Engel
Dartmouth Scholarship
During pregnancy the immune system of the mother must protect any activation that may negatively affect the fetus. Changes in susceptibility to infection as well as resolution of some autoimmune disorders represent empirical evidence for pregnancy related alterations in immunity. Sex hormones reach extremely high levels during pregnancy and have been shown to have direct effects on many immune functions including the antiviral response of dendritic cells. Among the immunologically active proteins secreted by monocyte derived DCs (MDDC) are the alpha-defensins 1-3. This family of cationic antimicrobial peptides has a broad spectrum of microbicidal activity and has also been shown …
Lack Of Il-15 Results In The Suboptimal Priming Of Cd4+ T Cell Response Against An Intracellular Parasite, Crescent L. Combe, Magali M. Moretto, Joseph D. Schwartzman, Jason P. Gigley, David J. Bzik, Imtiaz A. Khan
Lack Of Il-15 Results In The Suboptimal Priming Of Cd4+ T Cell Response Against An Intracellular Parasite, Crescent L. Combe, Magali M. Moretto, Joseph D. Schwartzman, Jason P. Gigley, David J. Bzik, Imtiaz A. Khan
Dartmouth Scholarship
IFN-gamma-producing CD4+ T cells, although important for protection against acute Toxoplasma gondii infection, can cause gut pathology, which may prove to be detrimental for host survival. Here we show that mice lacking IL-15 gene develop a down-regulated IFN-gamma-producing CD4+ T cell response against the parasite, which leads to a reduction in gut necrosis and increased level of survival against infection. Moreover, transfer of immune CD4+ T cells from WT to IL-15-/- mice reversed inhibition of gut pathology and caused mortality equivalent to levels of parental WT mice. Down-regulated CD4+ T cell response in the absence of IL-15, manifested as reduced …
Characterization Of The Cd154-Positive And Cd40-Positive Cellular Subsets Required For Pathogenesis In Retrovirus-Induced Murine Immunodeficiency, Kathy A. Green, Randolph J. Noelle, Brigit G. Durell, William R. Green
Characterization Of The Cd154-Positive And Cd40-Positive Cellular Subsets Required For Pathogenesis In Retrovirus-Induced Murine Immunodeficiency, Kathy A. Green, Randolph J. Noelle, Brigit G. Durell, William R. Green
Dartmouth Scholarship
Genetically susceptible C57BL/6 (B6) mice that are infected with the LP-BM5 isolate of murine retroviruses develop profound splenomegaly, lymphadenopathy, hypergammaglobulinemia, terminal B-cell lymphomas, and an immunodeficiency state bearing many similarities to the pathologies seen in AIDS. Because of these similarities, this syndrome has been called murine AIDS (MAIDS). We have previously shown that CD154 (CD40 ligand)-CD40 molecular interactions are required both for the initiation and progression of MAIDS. Thus, in vivo anti-CD154 monoclonal antibody (MAb) treatment inhibited MAIDS symptoms in LP-BM5-infected wild-type mice when either a short course of anti-CD154 MAb treatment was started on the day of infection or …
Lineage-Restricted Function Of Nuclear Factor Kappab-Inducing Kinase (Nik) In Transducing Signals Via Cd40., Norman Garceau, Yoko Kosaka, Sally Masters, John Hambor, Reiko Shinkura, Tasuko Honjo, Randolph J. Noelle
Lineage-Restricted Function Of Nuclear Factor Kappab-Inducing Kinase (Nik) In Transducing Signals Via Cd40., Norman Garceau, Yoko Kosaka, Sally Masters, John Hambor, Reiko Shinkura, Tasuko Honjo, Randolph J. Noelle
Dartmouth Scholarship
CD40 signaling in B cells and dendritic cells (DCs) is critical for the development of humoral and cell-mediated immunity, respectively. Nuclear factor kappaB (NF-kappaB)-inducing kinase (NIK) has been implicated as a central transducing kinase in CD40-dependent activation. Here, we show that although NIK is essential for B cell activation, it is dispensable for activation of DCs. Such data provide compelling evidence that different intermediary kinases are used by different cellular lineages to trigger NF-kappaB activation via CD40.