Search results for "complex"
showing 10 items of 5889 documents
Impact of MHC class I alleles on the M. tuberculosis antigen-specific CD8+ T-cell response in patients with pulmonary tuberculosis
2007
Challenged by scattered understanding of protective immunity to Mycobacterium tuberculosis (MTB), we have mapped peptide epitopes to human leukocyte antigen (HLA)-A*0101, A*0201, A*1101, A*2402, B*0702, B*0801 and B*1501 of the secreted mycobacterial antigen Ag85B, a vaccine candidate that may be associated with immune protection. Affinity (ED(50)) and half-life (t(1/2), off-rate) analysis for individual peptide species on HLA-A and HLA-B molecules revealed binding ranges between 10(-3) and 10(-7) M. After selection of the best matches, major histocompatibility complex class I/peptide tetramer complexes were constructed to measure the CD8+ T-cell responses directly ex vivo in peripheral blo…
Human papillomavirus infection requires cell surface heparan sulfate.
2001
ABSTRACT Using pseudoinfection of cell lines, we demonstrate that cell surface heparan sulfate is required for infection by human papillomavirus type 16 (HPV-16) and HPV-33 pseudovirions. Pseudoinfection was inhibited by heparin but not dermatan or chondroitin sulfate, reduced by reducing the level of surface sulfation, and abolished by heparinase treatment. Carboxy-terminally deleted HPV-33 virus-like particles still bound efficiently to heparin. The kinetics of postattachment neutralization by antiserum or heparin indicated that pseudovirions were shifted on the cell surface from a heparin-sensitive into a heparin-resistant mode of binding, possibly involving a secondary receptor. Alpha-6…
TAP-polymorphisms in juvenile onset psoriasis and psoriatic arthritis.
1996
Abstract Juvenile onset psoriasis is strongly associated with the HLA-class I genes Cw6 and B57 whereas patients with psoriatic arthritis show an increased frequency of HLA-B27. It is unclear whether additional major histocompatibility genes also increase disease susceptibility. The TAP genes (transporter associated with antigen processing) encode two membrane-spanning proteins that translocate antigenic peptides from the cytoplasm into the endoplasmic reticulum. Comparison of 60 patients with juvenile onset psoriasis, 63 psoriatic arthritis patients, and 101 caucasoid controls revealed an increase of the TAP1 ∗ 0101 allele in the psoriasis group, that could not be explained by linkage to o…
Major histocompatibility complex regulation of the class of the immune response: the H-2d haplotype determines poor interferon-γ response to several …
1990
The lymph node cells of CBA (H-2k), but not BALB/c (H-2d) mice, release interferon (IFN)-gamma into the supernatant when immunized with picryl chloride epicutaneously and then exposed to antigen (haptenized cells) in vitro 4 days later. The failure in IFN-gamma production maps to the major histocompatibility complex (MHC; H-2d) in the congenic BALB/c, BALB/k and BALB/b mice. The evidence that this is an MHC regulation of the class of response to a range of antigens and not a classical Ir gene effect is (a) the difference is seen with several antigens including picryl chloride, "oxazolone" and purified protein derivative of tuberculin and (b) BALB/c mice, which fail to produce IFN-gamma, sho…
Myxoma virus Leukemia-associated protein is responsible for major histocompatibility complex class I and Fas-CD95 down-regulation and defines scrapin…
2002
ABSTRACTDown-modulation of major histocompatibility class I (MHC-I) molecules is a viral strategy for survival in the host.Myxoma virus, a member of thePoxviridaefamily responsible for rabbit myxomatosis, can down-modulate the expression of MHC-I molecules, but the viral factor(s) has not been described. We cloned and characterized a gene coding for an endoplasmic reticulum (ER)-resident protein containing an atypical zinc finger and two transmembrane domains, which we called myxoma virus leukemia-associated protein (MV-LAP). MV-LAP down-regulated surface MHC-I and Fas-CD95 molecules upon transfection; the mechanism probably involves an exacerbation of endocytosis and was lost when the ER r…
Review of 8 years of experience with Infanrix hexa (DTPa-HBV-IPV/Hib hexavalent vaccine).
2009
Combination vaccines that include multiple antigens within one formulation are now widely accepted as an effective means of eliciting protection against several diseases at the same time. Owing to improvements in quality and convenient modes of administration, they have become part of routine pediatric practice. Hexavalent vaccines, including diphtheria, tetanus, pertussis, hepatitis B, polio and Haemophilus influenzae type b antigens represent the latest advance in the development of combination vaccines. Over 8 years since its first licensure, this review looks at the immunogenicity, efficacy and safety profile of the only hexavalent pediatric vaccine currently in use--Infanrix hexa (diph…
Interaction of Human Phagocytes with Pigmentless Aspergillus Conidia
2000
ABSTRACT A defect in the pksP gene of Aspergillus fumigatus is associated with the loss of conidial pigmentation, a profound change of the conidial surface structure, and reduced virulence. The structural change of the conidial surface structure was not observed in similar A. nidulans wA mutants. Our data indicate that the pigment of both species is important for scavenging reactive oxygen species and for protection of conidia against oxidative damage.
Differentiation of Effector/Memory Vδ2 T Cells and Migratory Routes in Lymph Nodes or Inflammatory Sites
2003
Vδ2 T lymphocytes recognize nonpeptidic antigens without presentation by MHC molecules and mount both immediate effector functions and memory responses after microbial infection. However, how Vδ2 T cells mediate different facets of a memory response remains unknown. Here, we show that the expression of CD45RA and CD27 antigens defines four subsets of human Vδ2 T cells with distinctive compartmentalization routes. Naive CD45RA+CD27+ and memory CD45RA−CD27+ cells express lymph node homing receptors, abound in lymph nodes, and lack immediate effector functions. Conversely, memory CD45RA−CD27− and terminally differentiated CD45RA+CD27− cells, which express receptors for homing to inflamed tissu…
Low Density Lipoprotein Receptor-related Protein (LRP) Interacts with Presenilin 1 and Is a Competitive Substrate of the Amyloid Precursor Protein (A…
2005
Presenilin 1 (PS1) is a critical component of the gamma-secretase complex, which is involved in the cleavage of several substrates including the amyloid precursor protein (APP) and the Notch receptor. Recently, the low density receptor-related protein (LRP) has been shown to be cleaved by a gamma-secretase-like activity. We postulated that LRP may interact with PS1 and tested its role as a competitive substrate for gamma-secretase. In this report we show that LRP colocalizes and interacts with endogenous PS1 using coimmunoprecipitation and fluorescence lifetime imaging microscopy. In addition, we found that gamma-secretase active site inhibitors do not disrupt the interaction between LRP an…
Revisited BIA-MS combination: Entire "on-a-chip" processing leading to the proteins identification at low femtomole to sub-femtomole levels
2008
International audience; We present the results of a study in which biomolecular interaction analysis (BIA, Biacore 2000) was combined with mass spectrometry (MS) using entire "on-a-chip" procedure. Most BIA-MS studies included an elution step of the analyte prior MS analysis. Here, we report a low-cost approach combining Biacore analysis with homemade chips and MS in situ identification onto the chips without elution step. First experiments have been made with rat serum albumin to determine the sensitivity and validation of the concept has been obtained with an antibody/antigen couple. Our "on-a-chip" procedure allowed complete analysis by MS-MS of the biochip leading to protein identificat…