Identification of major histocompatibility complex class I alleles in Chinese rhesus macaques

Major histocompatibility complex (MHC) class I information is vital for understanding variance of immune responses in HIV vaccination and biomedical models. In this study, 9 Mamu-A and 13 Mamu-B alleles were identified from the cDNA products of 10 Chinese

Probabilistic Modeling of Rosette Formation

英文摘要: Rosetting, or forming a cell aggregate between a single target nucleated cell and a number of red blood cells (RBCs), is a simple assay for cell adhesion-mediated by specific receptor-ligand interaction. For example, rosette formation between sheep RBC and human lymphocytes has been used to differentiate T cells from B cells. Rosetting assay is commonly used to determine the interaction of Fc gamma-receptors (Fc gamma R) expressed on inflammatory cells and IgG-coated on RBCs. Despite its wide use in measuring cell adhesion, the biophysical parameters of rosette formation have not been well characterized. Here we developed a probabilistic model to describe the distribution of rosette sizes, which is Poissonian. The average rosette size is predicted to be proportional to the apparent two-dimensional binding affinity of the interacting receptor-ligand pair and their site densities. The model has been supported by experiments of rosettes mediated by four molecular interactions: Fc gamma RIII interacting with IgG, T cell receptor and coreceptor CD8 interacting with antigen peptide presented by major histocompatibility molecule, P-selectin interacting with P-selectin glycoprotein ligand 1 (PSGL-1), and L-selectin interacting with PSGL-1. The latter two are structurally similar and are different from the former two. Fitting the model to data enabled us to evaluate the apparent effective two-dimensional binding affinity of the interacting molecular pairs: 7.19x10(-5) mu m(4) for Fc gamma RIII-IgG interaction, 4.66x10(-3) mu m(4) for P-selectin-PSGL-1 interaction, and 0.94x10(-3) mu m(4) for L-selectin-PSGL-1 interaction. These results elucidate the biophysical mechanism of rosette formation and enable it to become a semiquantitative assay that relates the rosette size to the effective affinity for receptor-ligand binding.

A single amino acid defines cross-species reactivity of tree shrew (Tupaia belangeri) CD1d to human invariant natural killer T (iNKT) cells

P>The non-classical major histocompatibility complex (MHC) class I molecule CD1d presents lipid antigens to invariant natural killer T (iNKT) cells, which are an important part of the innate immune system. CD1d/iNKT systems are highly conserved in evoluti

长江江豚MHCD-RB基因第二外显子的分离鉴定

主要组织相容性复合体(Major histocompatibility complex,MHC)在脊椎动物的免疫系统中起着重要的作用,常作为适应性遗传标记应用于保护遗传学研究。长江江豚(Neophocaena phocaenoides asiaeorientalis)是惟一生活于淡水环境中的江豚种群,且已处于濒危状况。为了开发适用于长江江豚保护遗传学研究的MHC遗传标记,首次采用北象海豹(Mirounga angustirostris)的一对DRB基因引物对长江江豚的基因组进行扩增,从5个个体中成功扩增并

HLA-DRB1与胃腺癌临床特征及Hp感染关联性研究

<正> 人类主要组织相容性复合体(major histocompatibility complex,MHC)即人类白细胞抗原(human leucocyte antigen,HLA)复合体,定位于人第6号染色体短臂(6p23)上,具有单倍体(haplotype)遗传、高度多态性(polymorphism)、连锁不平衡(linkage disequilibrium)等遗传特征。我们运用序列特异性引物聚合酶链反应(sequence specific primer based polymerase chain

Effects of cyanobacterial toxin microcystin-LR on the transcription levels of immune-related genes in grass carp Ctenopharyngodon idella

Recent studies in mammals have revealed that the cyanobacterial toxin MC-LR suppresses immune functions. Nevertheless, immunotoxic effects of microcystins have been little studied in fish. In this paper, we present the profiles of the immune modulation of MC-LR in grass carp, and quantitative real-time PCR methodology was developed for the measurement of relative transcription changes of six immune-related genes in the spleen and head kidney of the grass carp Ctenopharyngodon idella, which were intraperitoneally injected with 50 mu g MC-LR center dot kg(-1) body weight in a three-week period. This study was focused exclusively on gene transcription level changes at different time points after MC-LR exposure, so, only one dose was given. The investigated genes were interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), type I interferon (Type I IFN), peptidoglycan recognition protein-L (PGRP-L), immunoglobulin M (IgM) and major histocompatibility complex class I (MHC-I) genes. The results demonstrated that the transcription levels of the TNF-alpha, type I IFN, and PGRP-L genes in the spleen and head kidney were significantly low at all time points, and those of IL-1 beta were significantly low in the head kidney at different time points. In addition, IgM and MHC-I transcription levels were only significantly low in the spleen and head kidney at 21 d postinjection. The changes in the transcription levels of immune-related genes induced by MC-LR confirmed its effect on inhibiting immune function at the transcription level.

Immunoprotective analysis of VhhP2, a Vibrio harveyi vaccine candidate

VhhP2 is an Outer membrane protein identified in a pathogenic Vibrio harveyi strain, T4, isolated from diseased fish. When used as a Subunit Vaccine, purified recombinant VhhP2 affords high level of protection upon Japanese flounder against V harveyi challenge. Vaccination with VhhP2 induced the expression of a number of immune-related genes, especially those encoding immunoglobulin M (IgM) and major histocompatibility complex (MHC) II alpha. A VhhP2 surface display system, in the form of the fish commensal strain FIR harboring the vhhP2-expressing plasmid pJVP, was constructed. PF3/pJVP is able to produce and present recombinant VhhP2 on cell surface. Vaccination of fish with live PF3/pJVP via intraperitoneal injection elicited Strong immunoprotection. Vaccination of fish orally with live PF3/pJVP embedded in alginate microspheres also induced effective immunoprotection. In addition, a VhhP2-based surface display system was created, in which VhhP2 serves as a carrier for the Surface delivery of a heterologous Edwardsiella tarda immunogen, Et18, that is fused in-frame to VhhP2. DH5 alpha/pJVP18, which expresses and surface-displays the VhhP2-Et18 chimera, proved to be an effective vaccine that call protect fish against infections by V. harveyi and E. tarda to the extents comparable to those produced by vaccination with purified recombinant VhhP2 and Et18, respectively. These data suggest that VhhP2 may be applied as a vaccine and a vaccine carrier against infections by V. harveyi and other pathogens such as F. tarda. (C) 2009 Elsevier Ltd. All rights reserved.