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881.
Kai Wang Chia-Lam Kou Kuang-Chuan Cheng Mi-Kyung Lee Bryan Paeper Ben F. Koop Tai-June Yoo Leroy Hood 《Immunogenetics》1994,40(2):116-122
Cosmid clones containing T-cell receptor Tcra V2 subfamily gene segments have been isolated from a BALB/c cosmid library and subjected to DNA sequence analysis. The V gene segments in the Tcra V2 subfamily differ from each other by 3%–7% at the nucleotide level and 5%–16% at the amino acid level. T-cell receptor Tcra V2 gene segment polymorphisms have been identified in the B10.PL and PL/J mouse strains with a Tcra V2 subfamily-specific probe. These V gene segment polymorphisms may cause the differential Tcra V gene usage in induced experimental allergic encephalomyelitis between B10.PL and PL/J mice.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide database and have been assigned the accession numbers U04312 and U04622-U04626 相似文献
882.
Hiroshi Mashimo Michael J. Chorney Pierre Pontarotti Douglas A. Fisher Leroy Hood Stanley G. Nathenson 《Immunogenetics》1992,36(5):326-332
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number M75875. 相似文献
883.
Autoimmune T cells: immune recognition of normal and variant peptide epitopes and peptide-based therapy 总被引:14,自引:0,他引:14
Experimental autoimmune encephalomyelitis (EAE) results from T helper (TH) cell recognition of myelin basic protein (MBP). We have characterized TH cell reactivity in B10.PL and PL/J (H-2u) mice to 39 N-terminal MBP peptide derivatives of different lengths and with individual amino acid substitutions. The peptide determinant of murine MBP can be divided into a minimal stimulatory core region (residues 1-6) and a tail region (residues 7-20) that alters the structure of the core region to affect both T cell recognition and MHC binding. Core recognition by B10.PL and PL/J mice is highly similar but in one case strain dependent. Peptide analogs that do not stimulate MBP-specific TH cells but bind to the I-Au molecule competitively inhibit T cell reactivity to MBP in vitro and prevent the induction of EAE in vivo. 相似文献
884.
Two genes, one polypeptide chain--fact or fiction? 总被引:7,自引:0,他引:7
L E Hood 《Federation proceedings》1972,31(1):177-187
885.
D W Mann I Stroynowski L Hood J Forman 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(1):318-322
Ld/Q7d, a hybrid molecule consisting of alpha-1 and alpha-2 domains from H-2Ld and alpha-3 and carboxy-end components from Q7d, was expressed on the surface of CRL-3A rat liver cells. This molecule retained serologic H-2Ld epitopes. The Ag is attached to the cell membrane through a phosphatidyl-inositol linkage, characteristic of Qa-2 molecules. Both bulk cultured and cloned H-2Ld alloreactive CTL as well as H-2Ld restricted vesicular stomatitis virus-specific CTL lyse CRL-3A cells which express H-2Ld but show little or no lytic activity on cells which express the Ld/Q7d hybrid. These cells also fail to act as cold target competitors for alloreactive anti-H-2Ld CTL. However, cells expressing Ld/Q7d are not resistant to CTL mediated lysis because they can be killed in the presence of lectin. These data indicate that recognition of polymorphic class I CTL epitopes in the alpha-1 and alpha-2 domains are influenced by the structure of the carboxy-end of the molecule. 相似文献
886.
Patterns of plant species composition and their relationships to soil and topographic variables were investigated in tropical dry forests across the north central Yucatan, Mexico. Seven sites were studied in the oldest accessible forests along a 200–km transect oriented northwest to southeast; an eighth site was located in a little‐disturbed area located 75 km northeast of the transect. Two of the sites were on Mayan ruins. All sites were sampled using 9–24, 10m × 20m plots (<n= 132) for woody stems ≥ 3.0 cm diameter breast height. The important natural forest species were Bursera simaruba, Caesalpinia gaumeri, Gymnopodium floribundum, Piscidia piscipula, and Thouinia paucidentata. The two most important woody species in ruin woodlands were Brosimum alicastrum and Croton lundellii. Forest plots (n=108) had 17 species on average, ruin plots (n= 24) nine species. Mean basal area of stems at the forest plots (20.7 m2.ha‐1) was lower than in ruin plots (28.4 m2.ha‐1). Detrended Correspondence Analysis generally placed plots by site along the geographic transect. Natural forest plots and sites were separated from the plots on ruin sites. The five soil and topographic variables (slope, soil depth, percent surface rock, soil pH, total soil organic matter) differed significantly among sites. Plot values were correlated with DCA axe scores. Intersite floristic variation reflects an overall west to east environmental gradient affected by climate. 相似文献
887.
888.
889.
Kia Joo Puan John Seng Hooi Low Terence Wee Kiat Tan Joseph Tien Seng Wee Eng Huat Tan Kam Weng Fong Eu Tiong Chua Chenggang Jin José-Luis Giner Craig T. Morita Christopher Hood Keng Goh Kam M. Hui 《Cancer immunology, immunotherapy : CII》2009,58(7):1095-1107
Introduction Human Vγ2Vδ2 T cells play important role in immunity to infection and cancer by monitoring self and foreign isoprenoid metabolites
with their γδ T cell antigen receptors. Like CD4 and CD8 αβ T cells, adult peripheral Vγ2Vδ2 T cells represent a pool of heterogeneous
cells with distinct functional capabilities.
Purpose The aim of this study was to characterize the phenotypes and functions of various Vγ2Vδ2 T cell subsets in patients with nasopharyngeal
carcinoma (NPC). We sought to develop a better understanding of the role of these cells during the course of disease and to
facilitate the development of immunotherapeutic strategies against NPC.
Results Although similar total percentages of peripheral blood Vγ2Vδ2 T cells were found in both NPC patients and normal donors, Vγ2Vδ2
T cells from NPC patients showed decreased cytotoxicity against tumor cells whereas Vγ2Vδ2 T cells from normal donors showed
potent cytotoxicity. To investigate further, we compared the phenotypic characteristics of Vγ2Vδ2 T cells from 96 patients
with NPC and 54 healthy controls. The fraction of late effector memory Vγ2Vδ2 T cells (TEM RA) was significantly increased in NPC patients with corresponding decreases in the fraction of early memory Vγ2Vδ2 T cells
(TCM) compared with those in healthy controls. Moreover, TEM RA and TCM Vγ2Vδ2 cells from NPC patients produced significantly less IFN-γ and TNF-α, potentially contributing to their impaired cytotoxicity.
Radiotherapy or concurrent chemo-radiotherapy further increased the TEM RA Vγ2Vδ2 T cell population but did not correct the impaired production of IFN-γ and TNF-α observed for TEM RA Vγ2Vδ2 T cells.
Conclusion We have identified distinct alterations in the Vγ2Vδ2 T cell subsets of patients with NPC. Moreover, the overall cellular
effector function of γδ T cells is compromised in these patients. Our data suggest that the contribution of Vγ2Vδ2 T cells
to control NPC may depend on the activation state and differentiation of these cells.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
890.