Block of T cell development in P53-deficient mice accelerates development of lymphomas with characteristic RAG-dependent cytogenetic alterations

SummaryMice deficient in the DNA damage sensor P53 display normal T cell development but eventually succumb to thymic lymphomas. Here, we show that inactivation of the TCR β gene enhancer (Eβ) results in a block of T cell development at stages where recombination-activating genes (RAG) are expressed. Introduction of the Eβ mutation into p53−/− mice dramatically accelerates the onset of lethal thymic lymphomas that harbor RAG-dependent aberrant rearrangements, chromosome 14 and 12 translocations, and amplification of the chromosomal region 9A1–A5.3. Phenotypic and genetic analyses suggest that lymphomas emerge through a normal thymocyte development pathway. These findings provide genetic evidence that block of lymphocyte development at stages with RAG endonuclease activity can provoke lymphomagenesis on a background with deficient DNA damage responses

Anti-inflammatory effects of Radix Gentianae Macrophyllae (Qinjiao), Rhizoma Coptidis (Huanglian) and Citri Unshiu Pericarpium (Wenzhou migan) in animal models

<p>Abstract</p> <p>Background</p> <p>KHU14, an ethanolic extract of <it>Radix Gentianae Macrophyllae </it>(<it>Qinjiao</it>), <it>Rhizoma Coptidis </it>(<it>Huanglian</it>) and <it>Citri Unshiu Pericarpium </it>(<it>Wenzhou migan</it>) was tested for its anti-inflammatory effects.</p> <p>Methods</p> <p>Three out of 20 herbs were found to have anti-inflammatory effects. The formulation of these herbs, i.e. KHU14 was tested for croton oil-induced ear edema, carrageenan-induced paw edema, acetic acid-induced capillary permeability, cotton pellet and delayed type hypersensitivity.</p> <p>Results</p> <p>KHU14 exhibited anti-inflammatory effects in animal models of acute and chronic inflammation. The anti-inflammatory activity of KHU14 observed was comparable to that of celecoxib. KHU14 inhibited the production of NO and PGE₂in LPS/IFN-gamma-stimulated peritoneal macrophages, and reduced edema and the amount of infiltrated cells in animal models.</p> <p>Conclusion</p> <p>KHU14 exhibited anti-inflammatory effects as demonstrated in typical immunological tests for anti-inflammation <it>in vitro </it>and <it>in vivo</it>.</p

Identification of dentinogenic cell-specific surface antigens in odontoblast-like cells derived from adult dental pulp

Abstract Background Odontoblast is a unique progenitor that plays a role in dentin formation. So far, the dentinogenic differentiation of dental pulp stem cells and the role of surface molecules of odontoblasts in dentinogenesis are not well known yet. In this study, we obtained odontoblast-like cells from human dental pulp cells and screened odontoblast-specific cell surface antigens by decoy immunization. Methods Through decoy immunization with intact odontoblast-like cells derived from human dental pulp cells, we constructed 12 monoclonal antibodies (mAbs) of IgG type, and their binding affinities for cell surface of odontoblast-like cells were analyzed by flow cytometry. Immunoprecipitation, mass spectrometry, and immunohistochemistry were performed to demonstrate odontoblast-specific antigens. Odontoblasts were sorted by these mAbs using magnetic-activated cell sorting system, and their mineralization efficiency was increased after sorting. Results We constructed 12 mAbs of IgG type, which had a strong binding affinity for cell surface antigens of odontoblast-like cells. In human adult tooth, these mAbs accumulated in the odontoblastic layer between dentin and pulp and in the perivascular region adjacent to the blood vessels in the pulp core. Cell surface expression of the antigenic molecules was increased during odontogenic cytodifferentiation and decreased gradually as dentinogenic maturation progressed. Proteomic analysis showed that two representative antigenic molecules, OD40 and OD46, had the potential to be components for cell adhesion and extracellular matrix structures. Conclusion These results suggest that mAbs will be useful for detecting and separating odontoblasts from the primary pulp cells and other lineage cells and will provide information on the structures of extracellular matrix and microenvironment that appears during the dentinogenic differentiation

Enhanced expression of cell-surface B-cell receptor-associated protein 31 contributes to poor survival of non-small cell lung carcinoma cells.

B-cell receptor-associated protein 31 (BAP31) is an endoplasmic reticulum (ER) membrane protein which plays a role as a molecular chaperone for the newly synthesized transmembrane proteins. BAP31 is also an important apoptosis regulator for extrinsic apoptosis induction in the ER membrane. Recent studies have shown that BAP31 is also expressed on the surface of embryonic stem cells. However, the function of cell surface BAP31 (csBAP31) still remains unclarified. In an attempt to search for surface markers on tumorspheres, here, we generated monoclonal antibodies (MAbs) against the sphere cells from the non-small cell lung carcinoma cell (NSCLC) line A549. SP1-B7, one of the MAbs, recognized csBAP31 whose expression was further increased on A549 sphere cells, as compared with A549 adherent cells. To investigate the role of csBAP31 in A549 cells, A549 adherent and sphere cells were stained with annexin V, propidium iodide, and SP1-B7. Interestingly, annexin V-high cells showed increased expression of csBAP31 as compared with annexin V-low cells. Caspase-3/7 activity was also increased in csBAP31-high cells as compared with csBAP31-low cells, suggesting that csBAP31-high cells are more sensitive to apoptosis. To further demonstrate the survival of csBAP31-positive A549 cells, csBAP31-positive and -negative A549 cells were sorted and subjected to the clonogenic survival assay. The colony number of csBAP31-positive A549 cells was decreased by approximately 1.7-fold, as compared that of csBAP31-negative A549 cells, suggesting that csBAP31-positve cells are sensitive to cell death indeed. The results suggest that enhanced expression of csBAP31 contributes to poor survival of NSCLC cells

Flow cytometric analysis of the percent expression of cell surface-expressed BAP31 on H9 hESCs.

<p>The cell surface expression of BAP31 was examined by flow cytometric analysis with various concentrations (1, 5, or 10 μg/ml) of rabbit (residues 165–246), goat (residues 125–158), or mouse (residues 137–161) anti-BAP31 antibodies. Shown are the percentages of BAP31-positive cells at the concentration of 10 μg/ml of antibodies.</p

MAb 297-D4 and MAb 144-A8 recognize BAP31 on the cell surface of hESCs.

<p>(A) Immunoprecipitation of biotinylated hESCs with α-BAP31, 297-D4, and 144-A8 antibodies. Immunoprecipitates were detected by western blots with the indicated antibodies or SA-HRP. (B) Flow cytometric analysis of hESCs with anti-TRA-1-60, α-BAP31, 297-D4, or 144-A8 antibodies.</p