Search results for " IMMUNITY"
showing 10 items of 618 documents
The Molecular Anatomy of Human Hsp60 and its Similarity with that of Bacterial Orthologs and Acetylcholine Receptor Reveal a Potential Pathogenetic R…
2012
Heat-shock protein 60 (Hsp60) is ubiquitous and highly conserved being present in eukaryotes and prokaryotes, including pathogens. This chaperonin, although typically a mitochondrial protein, can also be found in other intracellular sites, extracellularly, and in circulation. Thus, it can signal the immune system and participate in the development of inflammation and immune reactions. Both phenomena can be elicited by human and foreign Hsp60 (e.g., bacterial GroEL), when released into the blood by infectious agents. Consequently, all these Hsp60 proteins become part of a complex autoimmune response characterized by multiple cross reactions because of their structural similarities. In this s…
Identification and relevance of the CD95-binding domain in the N-terminal region of ezrin.
2003
The CD95 (Fas/APO-1) linkage to the actin cytoskeleton through ezrin is an essential requirement for susceptibility to the CD95-mediated apoptosis in CD4+ T cells. We have previously shown that moesin was not involved in the binding to CD95. Here we further support the specificity of the ezrin/CD95 binding, showing that radixin did not bind CD95. The ezrin region specifically and directly involved in the binding to CD95 was located in the middle lobe of the ezrin FERM domain, between amino acids 149 and 168. In this region, ezrin, radixin, and moesin show 60-65% identity, as compared with the 86% identity in the whole FERM domain. Transfection of two different human cell lines with a green …
Regulatory T Cells and IL-10 Independently Counterregulate Cytotoxic T Lymphocyte Responses Induced by Transcutaneous Immunization
2011
Background: The imidazoquinoline derivate imiquimod induces inflammatory responses and protection against transplanted tumors when applied to the skin in combination with a cognate peptide epitope (transcutaneous immunization, TCI). Here we investigated the role of regulatory T cells (Treg) and the suppressive cytokine IL-10 in restricting TCI-induced cytotoxic T lymphocyte (CTL) responses. Methodology/Principal Findings: TCI was performed with an ointment containing the TLR7 agonist imiquimod and a CTL epitope was applied to the depilated back skin of C57BL/6 mice. Using specific antibodies and FoxP3-diphteria toxin receptor transgenic (DEREG) mice, we interrogated inhibiting factors after…
Designing disease-resistant crops : from basic knowledge to biotechnology
2020
Ancient records describe how plant diseases were attributed to many causes which included divine power, religious belief, and superstition. Far from these days, we now have detailed knowledge about how plant immunity is executed. Plants employ two types of sensors to perceive and defeat the litany of pathogenic organisms that attack them, whilst microbes deploy a myriad of specialized weapons to suppress immunity and promote infection. This opens a path to exploiting these insights to increase crop resistance. Here we describe novel biotechnological approaches for designing superior disease-resistant crops to fight agricultural losses in the field while reducing chemical inputs, towards a m…
Ageing and production of the cytokines in Chernobyl clean-up workers from Latvia
2009
Ageing and production of the cytokines in Chernobyl clean-up workers from Latvia Chronic low-grade inflammation with subsequent impairment of immune system function promotes the development of age-related diseases, such as cancers, degenerative and infection diseases. It is not yet clear, if exposure to ionising radiation accelerates the aging process. The aim of the present work was to estimate the production of several cytokines by peripheral blood cells of Latvia's Chernobyl clean-up workers depending on age. ELISA was employed to determine the plasma level of sIL-1β and sIL-6 as well as level of IL-4 and TNF-α spontaneous and 24h and 96h after in vitro stimulation of peripheral blood mo…
Two Antigenic Peptides from Genes m123 and m164 of Murine Cytomegalovirus Quantitatively Dominate CD8 T-Cell Memory in the H-2 d Haplotype
2001
ABSTRACT The importance of CD8 T cells for the control of cytomegalovirus (CMV) infection has raised interest in the identification of immunogenic viral proteins as candidates for vaccination and cytoimmunotherapy. The final aim is to determine the viral “immunome” for any major histocompatibility complex class I molecule by antigenicity screening of proteome-derived peptides. For human CMV, there is a limitation to this approach: the T cells used as responder cells for peptide screening are usually memory cells that have undergone in vivo selection. On this basis, pUL83 (pp65) and pUL123 (IE1 or pp68 to -72) were classified as immunodominant proteins. It is an open question whether this li…
Control of murine cytomegalovirus in the lungs: Relative but not absolute immunodominance of the immediate-early 1 nonapeptide during the antiviral c…
1998
Effective control by the immune system is a hallmark of cytomegalovirus (CMV) infection. Accordingly, human CMV disease is a medical problem restricted to the immunologically immature or immunocompromised host (for a review, see reference 21). Murine models have implicated natural killer (NK) cells and CD8 T cells in the control of CMV infection. While NK cells mediate early protection in genetically resistant mouse inbred strains (4, 5, 31, 51), CD8 T cells establish enduring protective memory and function as principal antiviral effectors in susceptible strains (31). Specifically, in the BALB/c strain, major histocompatibility complex (MHC) class I-restricted antiviral CD8 T cells resolve …
The Putative Natural Killer Decoy Early Genem04(gp34) of Murine Cytomegalovirus Encodes an Antigenic Peptide Recognized by Protective Antiviral CD8 T…
2000
ABSTRACTSeveral early genes of murine cytomegalovirus (MCMV) encode proteins that mediate immune evasion by interference with the major histocompatibility complex class I (MHC-I) pathway of antigen presentation to cytolytic T lymphocytes (CTL). Specifically, them152gene product gp37/40 causes retention of MHC-I molecules in the endoplasmic reticulum (ER)-Golgi intermediate compartment. Lack of MHC-I on the cell surface should activate natural killer (NK) cells recognizing the “missing self.” The retention, however, is counteracted by them04early gene product gp34, which binds to folded MHC-I molecules in the ER and directs the complex to the cell surface. It was thus speculated that gp34 mi…
Processing and Presentation of Murine Cytomegalovirus pORFm164-Derived Peptide in Fibroblasts in the Face of All Viral Immunosubversive Early Gene Fu…
2002
ABSTRACTCD8 T cells are the principal effector cells in the resolution of acute murine cytomegalovirus (mCMV) infection in host organs. This undoubted antiviral and protective in vivo function of CD8 T cells appeared to be inconsistent with immunosubversive strategies of the virus effected by early (E)-phase genesm04,m06, andm152. The so-called immune evasion proteins gp34, gp48, and gp37/40, respectively, were found to interfere with peptide presentation at different steps in the major histocompatibility complex (MHC) class I pathway of antigen processing and presentation in fibroblasts. Accordingly, they were proposed to prevent recognition and lysis of infected fibroblasts by cytolytic T…
The Immune Evasion Paradox: Immunoevasins of Murine Cytomegalovirus Enhance Priming of CD8 T Cells by Preventing Negative Feedback Regulation▿
2008
ABSTRACTCytomegaloviruses express glycoproteins that interfere with antigen presentation to CD8 T cells. Although the molecular modes of action of these “immunoevasins” differ between cytomegalovirus species, the convergent biological outcome is an inhibition of the recognition of infected cells. In murine cytomegalovirus, m152/gp40 retains peptide-loaded major histocompatibility complex class I molecules in acis-Golgi compartment, m06/gp48 mediates their vesicular sorting for lysosomal degradation, and m04/gp34, although not an immunoevasin in its own right, appears to assist in the concerted action of all three molecules. Using the Ld-restricted IE1 epitope YPHFMPTNL in the BALB/c mouse m…