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81.
Mário Almeida‐Neto Daniella M. B. Frensel Werner Ulrich 《Global Ecology and Biogeography》2012,21(7):772-777
Baselga [Partitioning the turnover and nestedness components of beta diversity. Global Ecology and Biogeography, 19 , 134–143, 2010] proposed pairwise (βnes) and multiple‐site (βNES) beta‐diversity measures to account for the nestedness component of beta diversity. We used empirical, randomly created and idealized matrices to show that both measures are only partially related to nestedness and do not fit certain fundamental requirements for consideration as true nestedness‐resultant dissimilarity measures. Both βnes and βNES are influenced by matrix size and fill, and increase or decrease even when nestedness remains constant. Additionally, we demonstrate that βNES can yield high values even for matrices with no nestedness. We conclude that βnes and βNES are not true measures of the nestedness‐resultant dissimilarity between sites. Actually, they quantify how differences in species richness that are not due to species replacement contribute to patterns of beta diversity. Finally, because nestedness is a special case of dissimilarity in species composition due to ordered species loss (or gain), the extent to which differences in species composition is due to nestedness can be measured through an index of nestedness. 相似文献
82.
Makino N Toyofuku T Takegahara N Takamatsu H Okuno T Nakagawa Y Kang S Nojima S Hori M Kikutani H Kumanogoh A 《FEBS letters》2008,582(28):3935-3940
Dilated cardiomyopathy often results from autoimmunity triggered by microbial infections during myocarditis. However, it remains unclear how immunological disorders are implicated in pathogenesis of autoimmune myocarditis. Here, we demonstrated that Sema4A, a class IV semaphorin, plays key roles in experimental autoimmune myocarditis (EAM). Dendritic cells pulsed with myosin heavy chain-α peptides induced severe myocarditis in wild-type mice, but not in Sema4A-deficient mice. In adoptive transfer experiments, CD4+ T-cells from wild-type mice induced severe myocarditis, while CD4+ T-cells from Sema4A-deficient mice exhibited considerably attenuated myocarditis. Our results indicated that Sema4A is critically involved in EAM by regulating differentiation of T-cells. 相似文献
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The construction and in vitro testing of a photo-activatable anti-tumour immuno-regulatory antibody is described. In this ‘cloaked’ folated anti-CD3 antibody conjugate, the folate portion of the conjugate is free to bind to folate receptor expressing cancer cells, whilst the anti-CD3 activity is effectively rendered inert by a coating of photo-labile 2-nitrobenzyl groups. On irradiation with UV-A light the activity of the anti-CD3 antibody is restored, not only when it is required, but more importantly, only where it is required. The conjugate can then attract killer T-cells to the surface of the tumour cells and kill them. Unirradiated normal tissues, to which the conjugate has been targeted by specific and non-specific binding, remain unharmed. We believe that these ‘photo-switchable’ conjugates could be used to markedly improve the targeting of the immune response to folate receptor (FR) expressing ovarian and breast cancers whilst minimising the side effects in the rest of the body. 相似文献
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86.
Takeshi Kawahara Akira Ichikawa Yoshinori Katakura Kiichiro Teruya Takahisa Yoshida Masahiro Kikuchi Masanori Kamei Shuichi Hashizume Sanetaka Shirahata 《Cytotechnology》2001,36(1-3):171-177
Adult T cell leukemia (ATL) is a malignant disease characterized by tumorous proliferation of CD4+ T cells infected with retrovirus human T cell leukemia virus Type-I (HTLV-I) and concurs with an autoimmune disease and cancer
due to attenuated immune response. In this study, we established ATL patient derived B-cell line TM-1 producing cancer-specific
IgM antibodies, and further characterized its antigen specificity by establishing hybridomas fused with human-mouse origin
hetero-myeloma cell line RF-S1. We established three hybridoma cell lines termed 2E12, 3E9, and 3E10, which continuously secreted
human IgM antibodies. Immunohistochemical staining of formalin-fixed tissue section using antibodies secreted from these hybridomas
showed that these antibodies specifically recognized tumor sites of human colon adenocarcinomas. Antibody produced from hybridoma
3E9 bound to some of leukemic cell lines, but not to normal human PBL, which was evidenced by the flow cytometric analysis,
indicating that antibody produced from 3E9 recognizes cell surface antigen specifically expressed in the leukemic cells.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
N. P. Sharova 《Russian Journal of Developmental Biology》2006,37(3):139-145
A lot of facts that require understanding have been accumulated since immune proteasomes were discovered and their relationship with the immune response was established. For example, why are immune proteasomes present in all studied mammalian organs and tissues, including nonlymphoid tissues? What is responsible for differences in the ratio of immune to constitutive proteasomes in different organs? Are the functions of immune proteasomes related to the immune response alone, as was shown initially, or not? Are immune proteasomes formed simultaneously in different organs during ontogenesis? An attempt is made in this review to answer these and other related questions. 相似文献
88.
Priv.-Doz. Dr. Brita von Gaudecker Ulrich Pfingsten Hans-Konrad Müller-Hermelink 《Cell and tissue research》1984,238(1):135-143
Summary In the present study attention was focussed on several lymphoid subpopulations and specific stationary cells of the human tonsilla palatina. They were labeled at the light- and electron-microscopic levels by means of monoclonal antibodies to cell surface antigens. Cells resembling interdigitating cells (IDC-like cells) within the crypt epithelium and the interdigitating cells in the parafollicular T-cell region express the HLA-DR antigen. This fact suggests a relationship between these two populations of cells. Both cell types were frequently found in close contact to T-helper cells labeled with Anti-Leu 3a. This fact is discussed as a confirmation of earlier suggestions that the tonsillar crypt epithelium serves as T-cell region. Cytotoxic/ suppressor-T cells (OKT 8
+) and Leu 7-positive cells do not appear to contact interdigitating cells. Anti-Leu 7 is a monoclonal antibody, that defines a differentiation antigen shown to be selectively expressed on human natural killer cells (NK-cells). With the use of the immuno-electron-microscopic labeling method it was possible to analyze the ultrastructure of this lymphoid subpopulation. Two morphologically distinguishable subtypes of Leu 7-positive cells populate different microenvironments: The Leu 7-positive large-granular lymphocyte was predominantly found in the crypt epithelium, while numerous Leu 7-positive cells located in the germinal centers had the appearance of small lymphocytes. This finding is discussed in favour of distinct phenotypes representing different stages in a differentiation pathway of the maturing NK-cell: Small Leu 7-positive lymphocytes in the germinal centers are supposed to be functionally inactive precursors, and only the Leu 7-positive large granulated lymphocytes in the crypt epithelium may represent differentiated active NK-cells. This interpretation is in agreement with the observation that the tonsilla palatina, in spite of containing numerous Leu 7-positive cells, shows only low NK-activity against tumor cells.Glossary of Abbreviations used in this Paper DAB
diamino-benzidine
- DMSO
dimethyl sulfoxide
- HLA
human leucocyte antigen
- HLA-DR
human leucocyte antigen, D-region related
- Ia-antigen
immune-associated antigen of the MHC
- IDC
interdigitating cell
- IDC-like cell
cell that resembles an interdigitating cell
- LGL
large granular lymphocyte
- MHC
major histocompatibility gene complex
- NK-cell
natural killer cell
- PBS
phosphate-buffered saline 相似文献
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