ABSTRACT
The transduction signals from the immobilisation of a class I heavy chain, HLA-A2, on a layer guided acoustic plate mode device, followed by binding of beta(2)-microglobulin and subsequent selective binding of a target peptide are reported.
Subject(s)
Biosensing Techniques/methods , HLA-A2 Antigen/metabolism , Streptavidin/metabolism , Biosensing Techniques/instrumentation , Humans , Microscopy, Acoustic , Protein Folding , Protein Interaction Mapping , beta 2-Microglobulin/metabolismABSTRACT
We show that at least half of patients with common variable immunodeficiency (CVID) have circulating CD8(+) T cells specific for epitopes derived from cytomegalovirus (CMV) and/or the Epstein-Barr virus (EBV). Compared to healthy age-matched subjects, more CD8(+) T cells in CVID patients were committed to CMV. Despite previous reports of defects in antigen presentation and cellular immunity in CVID, specific CD4(+) and CD8(+) T cells produced interferon (IFN)-gamma after stimulation with CMV peptides, and peripheral blood mononuclear cells secreted perforin in response to these antigens. In CVID patients we found an association between a high percentage of circulating CD8(+) CD57(+) T cells containing perforin, CMV infection and a low CD4/CD8 ratio, suggesting that CMV may have a major role in the T cell abnormalities described previously in this disease. We also show preliminary evidence that CMV contributes to the previously unexplained severe enteropathy that occurs in about 5% of patients.
Subject(s)
Common Variable Immunodeficiency/immunology , Herpesviridae Infections/immunology , Opportunistic Infections/immunology , T-Lymphocyte Subsets/immunology , CD8-Positive T-Lymphocytes/immunology , Colitis/immunology , Colitis/virology , Common Variable Immunodeficiency/complications , Cytomegalovirus Infections/complications , Cytomegalovirus Infections/immunology , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/immunology , Herpesviridae Infections/complications , Humans , Immunophenotyping , Interferon-gamma/biosynthesis , Membrane Glycoproteins/metabolism , Middle Aged , Opportunistic Infections/complications , Perforin , Pore Forming Cytotoxic Proteins/metabolismABSTRACT
Cytomegalovirus disease still remains a major cause of morbidity and mortality in hematopoietic stem cell transplantation recipients. The cell-mediated immune response is essential in the maintenance of latency and the resolution of primary infections. The identification of immunodominant cytomegalovirus antigens has enabled researchers to determine the best candidate antigens to be included in a cytomegalovirus vaccine. Such a vaccine would have to stimulate both a cell-mediated and humoral immune response. Recent advances have enabled the rapid identification of minimal cytotoxic epitopes required to trigger such responses. Epitope mapping to date has mainly focused on the pp65 antigen but other antigens such as IE1 are starting to be mapped. A human leukocyte antigen allele hierarchy is starting to emerge that is dependent on the alleles present in an individual; this is relevant when considering what peptides should be included in a vaccine. This review looks at the current methods available for epitope mapping and the progress that has been made to date.
Subject(s)
Cytomegalovirus Infections/prevention & control , Cytomegalovirus/immunology , Algorithms , Animals , Antigens, Viral/genetics , Antigens, Viral/immunology , CD8-Positive T-Lymphocytes/immunology , Cytomegalovirus/genetics , Cytomegalovirus/metabolism , Cytomegalovirus Infections/immunology , Cytomegalovirus Infections/therapy , Epitopes, T-Lymphocyte/analysis , Epitopes, T-Lymphocyte/immunology , Genetic Vectors/genetics , Genetic Vectors/immunology , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/immunology , Humans , Immediate-Early Proteins/genetics , Immediate-Early Proteins/immunology , Mice , Mice, Transgenic , Peptide Fragments/genetics , Peptide Fragments/immunology , Phosphoproteins/genetics , Phosphoproteins/immunology , Vaccines, Subunit/immunology , Vaccines, Subunit/therapeutic use , Viral Matrix Proteins/genetics , Viral Matrix Proteins/immunology , Viral Proteins/genetics , Viral Proteins/immunologyABSTRACT
We report the cloning and sequencing of the gene containing cytochrome c' (cycP) from the photosynthetic purple bacterium Rhodobacter capsulatus and the regions flanking that gene. Mutant strains unable to synthesize cytochrome c' had increased sensitivity to nitrosothiols and to nitric oxide (which binds to the heme moiety of cytochrome c').
