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Phospholipase C-gamma2 is essential for NK cell cytotoxicity and innate immunity to malignant and virally infected cells.

Phospholipase C-gamma2 (PLC-gamma2) is a key component of signal transduction in leukocytes. In natural killer (NK) cells, PLC-gamma2 is piv … d in PLC-gamma2-deficient cells, regardless of whether targets expressed NKG2D ligands, missed self major histocompatibility complex (MHC) class I, or whether NK cells were stimulated with IL-2 and antibodies specific for NKR-P1C, CD16, CD244, Ly49D, and Ly49H. Defective secretion was specific to cytotoxic granules because release of IFN-gamma on stimulation with IL-12 was normal …

Intrathecal production and secretion of vascular endothelial growth factor during Cryptococcal Meningitis.

BACKGROUND: Patients with cryptococcal meningitis (CM) show elevated intracranial pressure (ICP) and blood-brain barrier (BBB) disruption in … on by PBMCs induced by antigens strongly exceeded production by monocytes (P<.001). The addition of major histocompatibility complex class II antibody inhibited this production of VEGF (P=.005). Confirming the in vitro data, patients with CM showed significantly elevated VEGF levels in CSF (P<.001), plasma (P=.028), and serum (P<.001), compared with healthy control subjects. Calc …

Dendritic cells fused with core binding factor-beta positive acute myeloid leukaemia blast cells induce activation of cytotoxic lymphocytes.

Several reports have described various strategies of dendritic cell (DC) vaccination to induce specific T-cell responses in patients with acute myeloid leukaemia (AML). About 50-60% of AML cases blasts have chromosomal abnormalities, such as inv(16) or t(8,21), which could encode for leukaemia-specific antigenic peptide sequences, possibly presented in the context of self-major histocompatibility complex (MHC) molecules. As the co-culture of AML blasts with T lymphocytes seldom resulted in T-cell stimulation, we fused AML blasts with autologous DC to enhance this effect. The fusion cells expre…

The distribution of polymorphic Alu insertions within the MHC class I HLA-B7 and HLA-B57 haplotypes.

There are five polymorphic Alu insertion (POALIN) loci within the major histocompatibility complex (MHC) class I region that have been strongly associated with HLA class I alleles, such as HLA-A1, HLA-A2 and HLA-B57. In order to assess the variability and frequency of POALIN distribution within two common HLA-B haplotypes, we detected the presence of the MHC class I POALIN by PCR in a panel of 15 individuals with HLA-B57 and 47 homozygous individuals with 7.1 AH (HLA-B7, -Cw7, -A3) obtained from the Australian Bone Marrow Donor Registry, and also from four families (25 individuals) containing …

Liver regeneration in a retrorsine/CCl4-induced acute liver failure model: do bone marrow-derived cells contribute?

BACKGROUND/AIMS: Adult bone marrow contains progenitors capable of generating hepatocytes. Here a new liver failure model is introduced to assess whether bone marrow-derived progeny contribute to liver regeneration after acute hepatotoxic liver failure. METHODS: Retrorsine was used to inhibit endogenous hepatocyte proliferation, before inducing acute liver failure by carbon tetrachloride. Bone marrow chimeras were generated before inducing liver failure to trace bone marrow-derived cells. Therefore, CD45 and major histocompatibility complex (MHC) class I dimorphic rat models were applied. RE…

Preliminary crystallographic characterization of the human beta2 microglobulin His31Tyr mutant in a tetrameric assembly.

Patients receiving prolonged haemodialysis treatment are exposed to a variety of arthropathies and bone lesions arising from deposition of amyloid material in the skeletal system. beta2 microglobulin is the 11.7 kDa light chain of the class I major histocompatibility complex, from which it is normally released to plasmatic fluids, transported to kidneys and excreted. Owing to renal failure it accumulates, giving rise to dialysis-related amyloidosis, a severe disease found in patients receiving dialysis for several years. The three-dimensional structure of beta2 microglobulin is known to be bas…

Vaccine immunity to pathogenic fungi overcomes the requirement for CD4 help in exogenous antigen presentation to CD8+ T cells: implications for vaccine development in immune-deficient hosts.

Systemic fungal infections with primary and opportunistic pathogens have become increasingly common and represent a growing health menace in … hogen. In the absence of T helper cells, exogenous fungal antigens activated memory CD8+ cells in a major histocompatibility complex class I-restricted manner and CD8+ T cell-derived cytokines tumor necrosis factor alpha, interferon gamma, and granulocyte/macrophage colony-stimulating factor-mediated durable vaccine immunity. CD8+ T cells could also rely on alternate mechanisms f …

Lack of IFN-gamma-mediated induction of the class II transactivator (CIITA) through promoter methylation is predominantly found in developmental tumor cell lines.

Downregulation of major histocompatibility complex (MHC) molecules by tumor cells impairs cellular immune recognition and contributes to inefficient cell-mediated tumor eradication. Low or lack of expression of MHC molecules is frequently observed in early developmental or embryonically derived tumor cells. Considering the central role of the class II transactivator (CIITA) in MHC class II- and class I-mediated antigen presentation, we compared the induction of CIITA by interferon-gamma (IFN-gamma) in a diverse panel of developmental and more differentiated tumor cell lines. In contrast to the…

Lamina propria dendritic cells express activation markers and contact lymphocytes in chronic periodontitis.

BACKGROUND: Dendritic cells are characterized by shape, structure, and membrane molecule expression; they contact T lymphocytes to present a … ral epithelium but restricted to the basal layer in pocket epithelium; they did not usually express major histocompatibility complex (MHC)-II antigens nor contact lymphocytes. Dendritic cells were abundant in the lamina propria of pocket epithelium; they were MHC-II positive, admixed with CD4-positive and CD8-positive T lymphocytes, and, they expressed CD54, CD80, and CD86. Dendr …

Dendritic cell involvement in pulmonary granuloma formation elicited by bacillus calmette-guérin in rats.

Dendritic cells (DCs) are the most potent antigen-presenting cells that play a central role in initiating the primary immune response. Howev … ulomas. The OX62(+) cells isolated from the granulomatous lung showed intense surface expression of major histocompatibility complex class II, B7-1, and B7-2, and a lack of T cell- and monocyte/macrophage-specific markers. Their ultrastructural morphology was characteristic of DCs. Functionally, they had potent capacity to stimulate allogeneic T cells as well as purified protein …

Conjunctival T-cell subpopulations in Sjögren's and non-Sjögren's patients with dry eye.

PURPOSE: To examine the conjunctiva of patients with Sjögren's syndrome keratoconjunctivitis sicca (SS-KCS) and non-Sjögren's keratoconjunctivitis sicca (NS-KCS) for evidence of immune-based inflammation. METHODS: Conjunctival biopsy specimens were obtained from 15 patients with SS-KCS and 15 with NS-KCS. Immunohistochemistry was performed on frozen sections to characterize and quantify T-cell subtypes (CD3, CD4, and CD8) and markers of immune activation (major histocompatibility complex [MHC] class II: HLA-DR, HLA-DQ) and inflammation (intercellular adhesion molecule [ICAM]-1). The numbers o…

Cathepsins are upregulated by IFN-gamma/STAT1 in human muscle culture: a possible active factor in dermatomyositis.

The aim of this work was to study which genes upregulated by the IFN-gamma/STAT1 system in human muscle might be involved in the process of muscle fiber atrophy in dermatomyositis (DM). These proteins included proteases (cathepsins B and L, calpain), proteins implicated in apoptosis and cell cycle (Bcl-x(l), Fas, p21), structural proteins (beta-actin, utrophin, desmin), and other proteins whose expression is known to be modified by IFN-gamma (neural cell adhesion molecule (N-CAM), major histocompatibility complex-I (MHC-I)). We performed immunocytochemistry, Western blot, and semiquantitative …

Melanocyte destruction after antigen-specific immunotherapy of melanoma: direct evidence of t cell-mediated vitiligo.

Current strategies for the immunotherapy of melanoma include augmentation of the immune response to tumor antigens represented by melanosoma … . Analysis of the infiltrating lymphocytes in skin and tumor biopsies using T cell-specific peptide-major histocompatibility complex tetramers demonstrated a localized predominance of MART-1-specific CD8(+) T cells (>28% of all CD8 T cells) that was identical to the infused clones (as confirmed by sequencing of the complementarity-determining region 3). In contrast to skin biopsi …

HLA-B27 expression and reactive arthritis susceptibility in two patient cohorts infected with Salmonella Typhimurium.

BACKGROUND: Reactive arthritis (ReA) is an inflammatory arthritis triggered by certain gastrointestinal and genitourinary infections. Single source outbreaks of triggering infections provide an opportunity to elucidate host susceptibility factors in this disease. AIM: To determine the role of Major Histocompatibility Complex (MHC) Class I alleles in ReA susceptibility after two large single source outbreaks of Salmonella Typhimurium gastroenteritis. METHODS: A questionnaire screening for features of ReA and a request for HLA class I typing were sent to all patients affected by two single sou…

The expansion of human gammadelta T cells in response to Daudi cells requires the participation of CD4+ T cells.

The Burkitt's lymphoma cell line Daudi is a potent inducer of human gammadelta T-cell expansion. Using an in vitro culture system comprised of irradiated Daudi cells as stimulators and normal human lymphocytes as responders, the cellular determinants of this response were investigated. Three of four monoclonal antibodies (mAbs 1-1C4, L243, and 9.3F10) directed against disparate epitopes of human major histocompatibility complex (MHC) class II, as well as a mAb with specificity for CD4 (OKT4), inhibited the expansion of gammadelta T cells in response to Daudi cell stimulators. mAbs with a speci…

Те же аллели HLA-DQ определяют либо подверженность, либо устойчивость к различным аутоиммунным заболеваниям, вызываемым коксакевирусом.

Важной характеристикой аутоиммунных заболеваний является их связь с основными гистосопоставимыми сложными классами I и II. В этом исследовании мы сравнили сахарный диабет, зависящий от инсулина (IDDM), с идиопатической дилапсированной кардиомиопатией (IDC) с сугубо иммунологической точки зрения. Хотя органы-объекты отличаются друг от друга, будучи в одном случае бета-клетками поджелудочной железы, производящими инсулин, а в другом - миокитами сердца, многие аспекты иммунного разрушения конкретных тканей являются распространенными. Схожие, но различные штаммы Коксакивируса В с панкреотропной ил

Совпадение в аннотации оригинала
An important characteristic of autoimmune diseases is their association with major histocompatibility complex class I and class II alleles. In this study, we compared insulin-dependent diabetes mellitus (IDDM) with idiopathic dilated cardiomyopathy (IDC) from a strictly immunologic perspective. Although the target organs are different, being in one case the …

H2-M3-restricted T cells in bacterial infection: rapid primary but diminished memory responses.

Major histocompatibility complex (MHC) class Ib molecules have been implicated in CD8(+) T cell-mediated defenses against intracellular bacterial infection, but the relative importance of MHC class Ib-restricted T cells in antimicrobial immunity is unknown. In this report, we use MHC tetramers to characterize T cell responses restricted by H2-M3, an MHC class Ib molecule that selectively presents N-formyl peptides. We find that sizeable H2-M3-restricted T cell responses, occurring earlier than MHC class Ia-restricted T cell responses, are mounted after primary infection with the intracellular …

Neuronal apoptosis in fatal familial insomnia.

The possibility that neuronal loss in prion diseases occurs through an apoptotic process has been postulated and is consistent with the lack … ptotic neurons also correlated well with microglial activation as demonstrated by the expression of major histocompatibility complex class II antigens. PrPres immunostaining was almost invariably negative, consistent with previous data showing the lack of obvious correlation between neuronal loss and PrPres deposits in prion diseases.

Macrophages/microglia as 'sensors' of injury in the pineal gland of rats following a non-penetrative blast.

The pineal gland of adult rats was examined immunohistochemically and electron microscopically following exposure of the animals to a single blast equivalent to 110 kg TNT explosive. The most dramatic feature in rats killed at 7, 14 and 21 days after the blast was the upsurge of a large number of macrophages/microglia intensely immunostained with OX-42, OX-18, OX-6 and ED1 antibodies. These antibodies recognise the complement type three (CR3) receptors, major histocompatibility complex class I and class II (MHC I and MHC II) antigens and monocyte/macrophage antigens. Cell counts in OX-42 immun…

Familial aspects of narcolepsy-cataplexy in the Czech Republic.

A group of 153 probands with narcolepsy included 38 subjects (24.8%) with a familial incidence of excessive daytime sleepiness (EDS). In 15 … ssociated with cataplexy and "monosymptomatic" forms of narcolepsy and suggest the existence of non-major histocompatibility complex (MHC) susceptibility factors for narcolepsy.