Search results for "Lymphocyte"
showing 10 items of 2280 documents
Reconstitution of lymphocyte populations and cytomegalovirus viremia or disease after allogeneic peripheral blood stem cell transplantation
2003
Early reconstitution of lymphoid populations was monitored by immunophenotyping in 57 allogeneic peripheral blood stem cell (allo-PBSC) transplant patients either with or without cytomegalovirus (CMV) viremia or disease. Cell counts for total lymphocytes and CD4(+) T cells above the percentile 60th at day 14 postransplant were associated significantly with CMV viremia-free survival within 120 days after transplant. Recovery of total lymphocyte, CD3(+), and CD8(+) T-cell counts proceeded at a more rapid rate in CMV viremic patients than in nonviremic patients, irrespective of whether preemptive treatment with ganciclovir had been prescribed. Significant expansion of CD8(+) and CD8(+) CD57(+)…
Experimental Preemptive Immunotherapy of Murine Cytomegalovirus Disease with CD8 T-Cell Lines Specific for ppM83 and pM84, the Two Homologs of Human …
2001
ABSTRACTCD8 T cells are the principal antiviral effectors controlling cytomegalovirus (CMV) infection. For human CMV, the virion tegument protein ppUL83 (pp65) has been identified as a source of immunodominant peptides and is regarded as a candidate for cytoimmunotherapy and vaccination. Two sequence homologs of ppUL83 are known for murine CMV, namely the virion protein ppM83 (pp105) expressed late in the viral replication cycle and the nonstructural protein pM84 (p65) expressed in the early phase. Here we show that ppM83, unlike ppUL83, is not delivered into the antigen presentation pathway after virus penetration before or in absence of viral gene expression, while other virion proteins o…
Suppression of CD8+ T cell recognition in the immediate-early phase of human cytomegalovirus infection.
2012
Human cytomegalovirus (HCMV) interferes with MHC class I-restricted antigen presentation and thereby reduces recognition by CD8+ T-cells. This interference is mediated primarily by endoplasmic reticulum-resident glycoproteins that are encoded in the US2–11 region of the viral genome. Such a suppression of recognition would be of particular importance immediately after infection, because several immunodominant viral antigens are already present in the cell in this phase. However, which of the evasion proteins gpUS2–11 interfere(s) with antigen presentation to CD8+ T-cells at this time of infection is not known. Here we address this question, using recombinant viruses (RV) that express only o…
Identification of a Conserved HLA-A2-Restricted Decapeptide from the IE1 Protein (pUL123) of Human Cytomegalovirus
2002
Abstract Control of human cytomegalovirus (HCMV) infection is predominantly mediated by cytolytic CD8 + T lymphocytes (CTL). Among the roughly 200 HCMV-encoded polypeptides, the tegument protein pp65 (ppUL83) and the nonstructural IE1 protein are considered to be dominant CTL targets. Yet the importance of CTL against IE1 for protective immunity against HCMV reactivation and disease has remained elusive. Analyses have been difficult, as all MHC class I presented peptides of IE1 defined so far are located in parts of the protein that are variable between viral strains. In this study a conserved decameric peptide from IE1 (P6, IE1 354–363 ) that bound to HLA-A2 was identified. Using peptide-p…
Evaluating Human T-Cell Therapy of Cytomegalovirus Organ Disease in HLA-Transgenic Mice
2015
Reactivation of human cytomegalovirus (HCMV) can cause severe disease in recipients of hematopoietic stem cell transplantation. Although preclinical research in murine models as well as clinical trials have provided 'proof of concept' for infection control by pre-emptive CD8 T-cell immunotherapy, there exists no predictive model to experimentally evaluate parameters that determine antiviral efficacy of human T cells in terms of virus control in functional organs, prevention of organ disease, and host survival benefit. We here introduce a novel mouse model for testing HCMV epitope-specific human T cells. The HCMV UL83/pp65-derived NLV-peptide was presented by transgenic HLA-A2.1 in the conte…
Immune evasion proteins gpUS2 and gpUS11 of human cytomegalovirus incompletely protect infected cells from CD8 T cell recognition
2009
AbstractHuman cytomegalovirus (HCMV) encodes four glycoproteins, termed gpUS2, gpUS3, gpUS6 and gpUS11 that interfere with MHC class I biosynthesis and antigen presentation. Despite gpUS2–11 expression, however, HCMV infection is efficiently controlled by cytolytic CD8 T lymphocytes (CTL). To address the role of gpUS2 and gpUS11 in antigen presentation during viral infection, HCMV mutants were generated that expressed either gpUS2 or gpUS11 alone without coexpression of the three other proteins. Fibroblasts infected with these viruses showed reduced HLA-A2 and HLA-B7 surface expression. Surprisingly, however, CTL directed against the tegument protein pp65 and the regulatory IE1 protein stil…
Identification of transcripts of the T cell antigen receptor beta chain gene and major histocompatibility complex class II genes in antigen-presentin…
1988
The cloned murine cell line BK-BI-2.6.C6 has previously been shown to exhibit T cell characteristics, to synthesize and express MHC class II molecules, and to present protein antigens to antigen-dependent T cell clones. As a more definitive proof of the T-cell nature of these cells, transcripts of the rearranged T cell antigen receptor (TcR) beta gene were assessed by Northern blot analysis. BK-BI-2.6.C6 cells constitutively transcribe mRNA for the light chain of TcR and express the disulphide-linked alpha, beta TcR heterodimer at the cell surface. In addition mRNA for the polymorphic MHC class II subunits A alpha and A beta as well as for the invariant gamma chain were detected. BK-BI-2.6.…
PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide-Based Polymersomes.
2017
In this work, the first vaccine is reported based on a PeptoSome, which contains a model antigen (SIINFEKL) and adjuvant (CpG). PeptoSomes are polypept(o)ide-based polymersomes built of a block-copolymer with polysarcosine (PSar) as the hydrophilic block (X n = 111) and poly(benzyl-glutamic acid) (PGlu(OBn)) as the hydrophobic one (X n = 46). The polypept(o)ide is obtained with low dispersity index of 1.32 by controlled ring-opening polymerization. Vesicle formation by dual centrifugation technique allows for loading of vesicles up to 40 mol%. PeptoSomes are characterized by multiangle dynamic light scattering, static light scattering, and cryogenic transmission electron microscopy (cryoTEM…
T helper 1 response is correlated with widespread pain, fatigue, sleeping disorders and the quality of life in patients with fibromyalgia and is modu…
2019
Hyperbaric oxygen therapy (HBOT) has been used as treatment for different clinical conditions, including fibromyalgia (FM). HBOT modulates brain activity, ameliorates chronic pain and modifies the ratio of immune cells. Clinical studies have provided evidence that FM is associated with immune system dysregulation. In the present study we aimed to evaluate the effect of HBOT on immune system and on the quality of life-style of FM patients.Patients with primary FM and controls were treated with HBOT. Physical, emotional and social assessment, quality of sleep, tender points, intensity score, WPI and symptom severity were evaluated before and after HBOT. Furthermore, a characterisation of CD4 …
The Role of Interleukin 10 in the Regulation of Allergic Immune Responses
2001
Several clinical studies and animal models have shown that Th2 lymphocytes play a key role in the pathophysiology of IgE-mediated allergic immune responses like allergic rhinitis and asthma or venom anaphylaxis. Classical specific immunotherapy (SIT) that has been proven to be clinically effective can serve as a role model for immunological changes that are associated with amelioration of allergic diseases. During SIT, the Th2-dominated immune response is modified towards a Th1 response leading to a decline in allergen-specific IgE and an increase in allergen-specific IgG production. Most importantly, however, production of the immunosuppressive/-regulatory cytokine interleukin 10 (IL-10) i…