Search results for "Acquired"
showing 10 items of 522 documents
Immunity and Aging
2016
In the elderly, many alterations of innate and acquired immunity have been described and viewed as deleterious, hence the term immunosenescence. Immunosenescence is a complex process involving multiple reorganizational and developmentally regulated changes, rather than simple unidirectional decline of complete immune function. On the other hand, some immunological parameters are commonly notably reduced in the elderly, and reciprocally good function is tightly correlated to health status. Whereas innate immunity is relatively well preserved in elderly, acquired immunity is more susceptible due to both the functional decline associated with the passage of time, and to antigen burden to which…
Single tube real time PCR for detection of Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae and Legionella pneumophila from …
2012
We designed a multiplex real time PCR for rapid, sensitive and specific detection of Streptococcus pneumoniae, Legionella pneumophila, Chlamydophila pneumoniae and Mycoplasma pneumoniae. The study cases consisted of 129 patients with community acquired pneumonia (CAP). Bacteriological techniques were implemented for detection of the cultivable organisms. DNA were extracted from sputa, throat swabs, bronchoalveolar lavages and tracheal aspirates and used as templates in real time PCR. The primers and probes were designed for cbpA (S. pneumoniae), p1adhesin (M. pneumoniae), mip (L. pneumophila) and ompA (C. pneumoniae). After optimization of real time PCR for every organism, the experiments w…
Auditory brain stem responses in patients with human immunotropic virus infection of different stages.
1992
Thirty patients (26 men, 4 women) with human immunotropic virus infection of different stages were examined. Eleven patients had a history of i.v. drug abuse, nine patients had a history of treated lues infection, and one patient suffered from Kaposi's sarcoma. At the time of the examination, opportunistic infections or acute encephalitis were not apparent in any patient. All patients underwent otoneurological examinations, including pure-tone audiometry, caloric vestibular testing, and recording of the auditory brain stem responses (ABR). Six patients reported onset of hearing impairment during the last 3 yr. Two of them had flat sensorineural hearing loss; in the other cases, pure-tone au…
Molecular Evolution of Defense Pathways in Sponges: Self–Self-recognition and Fight against the Nonself
2016
This article provides an overview of the immune system in poriferans at a tissue, cellular, and molecular level. Despite their simple organization, sponges have developed molecular mechanisms to recognize and resist foreign organisms. They are able to distinguish among food organisms, pathogens, and sponge-associated organisms. Although they lack specialized immune cells, sponges display molecular precursors, which are similar to molecular mediators involved in innate and adaptive immune systems, present in more evolutionarily advanced taxa, as outlined in succeeding articles in the Phylogeny section.
Wheat Amylase Trypsin Inhibitors as Nutritional Activators of Innate Immunity
2015
While the central role of an adaptive, T cell-mediated immune response to certain gluten peptides in celiac disease is well established, the innate immune response to wheat proteins remains less well defined. We identified wheat amylase trypsin inhibitors (ATIs), but not gluten, as major stimulators of innate immune cells (dendritic cells > macrophages > monocytes), while intestinal epithelial cells were nonresponsive. ATIs bind to and activate the CD14-MD2 toll-like receptor 4 (TLR4) complex. This activation occurs both in vitro and in vivo after oral ingestion of purified ATIs or gluten, which is usually enriched in ATIs. Wheat ATIs represent a family of up to 17 proteins with molec…
Liver-primed memory T cells generated under noninflammatory conditions provide anti-infectious immunity.
2013
SummaryDevelopment of CD8+ T cell (CTL) immunity or tolerance is linked to the conditions during T cell priming. Dendritic cells (DCs) matured during inflammation generate effector/memory T cells, whereas immature DCs cause T cell deletion/anergy. We identify a third outcome of T cell priming in absence of inflammation enabled by cross-presenting liver sinusoidal endothelial cells. Such priming generated memory T cells that were spared from deletion by immature DCs. Similar to central memory T cells, liver-primed T cells differentiated into effector CTLs upon antigen re-encounter on matured DCs even after prolonged absence of antigen. Their reactivation required combinatorial signaling thro…
An innate cell-mediated, murine ulcerative colitis-like syndrome in the absence of nuclear factor of activated T cells.
2004
Abstract Background & Aims: Nuclear factor of activated T cells transcription factors plays a central role in immunity by regulating the expression of multiple cytokines and other regulatory molecules, many of which have been heavily implicated in the pathogenesis of inflammatory bowel disease. However, few studies have directly investigated the nuclear factor of activated T cells proteins in inflammatory bowel disease. We describe here a specific role for nuclear factor of activated T cells c2 in the pathogenesis of murine inflammatory bowel disease. Methods: Mice deficient for nuclear factor of activated T cells c2, recombinase activating gene-2, or both and transgenic or nontransgenic fo…
Synergistic activation of dendritic cells by combined Toll-like receptor ligation induces superior CTL responses in vivo.
2006
Toll-like receptors (TLRs) are able to interact with pathogen-derived products and their signals induce the coordinated activation of innate and adaptive immune mechanisms. Dendritic cells (DCs) play a central role in these events. As the different TLRs are able to trigger MyD88/TRIF-dependent and -independent signaling pathways, we wondered if the simultaneous activation of these signaling cascades would synergize with respect to DC activation and induce superior cytotoxic T-lymphocyte (CTL) activity in vivo. We observed that indeed the combined activation of MyD88-dependent and -independent signaling induced by TLR7 and TLR3 ligands provoked a more rapid and more sustained bone marrow–der…
Host immune response to Cryptosporidium parvum infection
2010
Species of the genus Cryptosporidium are protozoan parasites (Apicomplexa) that cause gastroenteritis in animals and humans. Of these Cryptosporidium parvum and Cryptosporidium hominis are the major causative agents of human cryptosporidiosis. Whereas infection is self-limiting in the immunocompetent hosts, immunocompromised individuals develop a chronic, life-threatening disease. As specific therapeutic or preventive interventions are not yet available, better understanding of the immune response to the parasite is required. This minireview briefly summarizes the factors involved in the innate and acquired immune response in this pathogen-host interaction with an emphasis on more recent da…
An Efficient Synthesis of Tenofovir (PMPA): A Key Intermediate Leading to Tenofovir-Based HIV Medicines
2020
Abstract: Herein, we report further improvements to the synthesis of tenofovir 1, the precursor to tenofovir disoproxil fumarate and tenofovir alafenamide fumarate. Starting from acyclic precursor diaminomalononitrile 12, a four-step protocol to tenofovir 1 will allow for vertical integration for more manufacturers. The key transformation is a more convergent one step procedure from 6 as compared to the current commercial process, with an improved yield from 59% (two steps) to 70%. Further improvements include eliminating the need for problematic magnesium tert-butoxide (MTB) and significant solvent reduction by eliminating the need for an intermediate workup. With the costs of HIV/AIDS tre…