Malignant transformation of human cell in vitro by the SV 40 DNA and related alteration in biological activity of cell membranes

In vitro cell transformation of human embryonic cells could be induced by DNA extracted from virions of SV 40 purified by density gradient centrifugation. The result shows clearly that cell transformation is in· duced by incorporation ofa part of viral DNA into the genome. In addition, for the purpose of clarifing the biological differences between the normal and transformant, the alteration of the cell membrane structures of transformants was observed from the mechanism of phagocytosis. The iron colloid particles are taken up by normal diploid fibroblasts but not by the human and hamster transformants. This fact suggests a difference in the molecular arrangement of the cell membranes between the normal and transformants. In the presence of histones, however, the transformants phagocytize the colloid particles very actively. The results show cell membranes of transformants are altered in the molecular structure responsible for the surface charge.</p

Construction of Childcare Support Program for two-children families: From Cooperation with Higashi-Hiroshima City Childcare Support Centers

The purpose of this study was to construct a childcare support program for the families who have two children to bring up. With the assistance of Higashi-Hiroshima city and childcare support centers, members from early childhood education research facility in Hiroshima University built up the program. In this program, it is demanded that the supporters draft the program while being conscious of four times, specifically approach-time, core-time, free-time and feedback-time. And this program also has four main components including topics, leaflet, picture books and reflection sheets. According to the practice, supporters can not only grow up with mothers and children by making use of their childcare specialty, but also can build a relationship of mutual trust with the participants. Besides, the support of the high quality is maintained by the collaboration of Higashi-Hiroshima city and childcare support centers and Hiroshima University.本研究は平成29年度「広島大学地域連携推進事業」に提案した「地域における虐待防止ペアレントトレーニングの効果検証－親が抱えるリスク要因の低減を目指して－」という研究の一環として，東広島市子ども家庭課の協力で実施したものである

Human NK cell development in hIL-7 and hIL-15 knockin NOD/SCID/IL2rgKO mice.

The immune system encompasses acquired and innate immunity that matures through interaction with microenvironmental components. Cytokines serve as environmental factors that foster functional maturation of immune cells. Although NOD/SCID/IL2rgKO (NSG) humanized mice support investigation of human immunity in vivo, a species barrier between human immune cells and the mouse microenvironment limits human acquired as well as innate immune function. To study the roles of human cytokines in human acquired and innate immune cell development, we created NSG mice expressing hIL-7 and hIL-15. Although hIL-7 alone was not sufficient for supporting human NK cell development in vivo, increased frequencies of human NK cells were confirmed in multiple organs of hIL-7 and hIL-15 double knockin (hIL-7xhIL-15 KI) NSG mice engrafted with human hematopoietic stem cells. hIL-7xhIL-15 KI NSG humanized mice provide a valuable in vivo model to investigate development and function of human NK cells

Hydrolyzed eggshell membrane immobilized on phosphorylcholine polymer supplies extracellular matrix environment for human dermal fibroblasts

We have found that a water-soluble alkaline-digested form of eggshell membrane (ASESM) can provide an extracellular matrix (ECM) environment for human dermal fibroblast cells (HDF) in vitro. Avian eggshell membrane (ESM) has a fibrous-meshwork structure and has long been utilized as a Chinese medicine for recovery from burn injuries and wounds in Asian countries. Therefore, ESM is expected to provide an excellent natural material for biomedical use. However, such applications have been hampered by the insolubility of ESM proteins. We have used a recently developed artificial cell membrane biointerface, 2-methacryloyloxyethyl phosphorylcholine polymer (PMBN) to immobilize ASESM proteins. The surface shows a fibrous structure under the atomic force microscope, and adhesion of HDF to ASESM is ASESM-dose-dependent. Quantitative mRNA analysis has revealed that the expression of type III collagen, matrix metalloproteinase-2, and decorin mRNAs is more than two-fold higher when HDF come into contact with a lower dose ASESM proteins immobilized on PMBN surface. A particle-exclusion assay with fixed erythrocytes has visualized secreted water-binding molecules around the cells. Thus, HDF seems to possess an ECM environment on the newly designed PMBN-ASESM surface, and future applications of the ASESM-PMBN system for biomedical use should be of great interest

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Study on the Mechanism of phagocytosis: Effect of Ionic strength on Adhesion of Fixed Red Blood Cells to Monocytes

For the purpose to clarify whether electrostatic contributes to the adhesion of red blood cell to monocyte, first phase of phagocytosis, was studied in vitro in ion deficient environments comparing with that in ionic environments. The experiments were carried out by using mouse ascites macrophage and the fresh and fixed red blood cells of mouse and chicken. Observations revealed that in Hanks' solution, the fixed red blood cells adhered to the monocyte, while fresh red blood cells of both species did not. In isotonic sugar aqueous solutions, however, the fixed red blood cells did not adhere to the monocyte. The test in the varied ionic concentration proved that number percent of monocytes adhering the fixed red blood cells to the total monocytes reduced in proportion to logaritsm of the decrease in ionic strength of the media. Concentration of Ca(++) and Mg(++) and pH of the media gave actually no effect on the red blood cell adhesion to the monocyte. The red blood cells fixed and conditioned with methylation treatment adhered to the monocytes even in ion free sucrose solution, but those conditioned with desamination treatment did not. From these results it is concluded that the ionic strength in the media is a decidive factor for the fixed red blood cell adhesion to the macrophage. Discussion was made on the mechanism of the adhesion from the view point of lyopobic and lyopilic colloid mechanism

Study on the Mechanism of phagocytosis: Effect of Ionic strength on Adhesion of Fixed Red Blood Cells to Monocytes

For the purpose to clarify whether electrostatic contributes to the adhesion of red blood cell to monocyte, first phase of phagocytosis, was studied in vitro in ion deficient environments comparing with that in ionic environments. The experiments were carried out by using mouse ascites macrophage and the fresh and fixed red blood cells of mouse and chicken. Observations revealed that in Hanks' solution, the fixed red blood cells adhered to the monocyte, while fresh red blood cells of both species did not. In isotonic sugar aqueous solutions, however, the fixed red blood cells did not adhere to the monocyte. The test in the varied ionic concentration proved that number percent of monocytes adhering the fixed red blood cells to the total monocytes reduced in proportion to logaritsm of the decrease in ionic strength of the media. Concentration of Ca(++) and Mg(++) and pH of the media gave actually no effect on the red blood cell adhesion to the monocyte. The red blood cells fixed and conditioned with methylation treatment adhered to the monocytes even in ion free sucrose solution, but those conditioned with desamination treatment did not. From these results it is concluded that the ionic strength in the media is a decidive factor for the fixed red blood cell adhesion to the macrophage. Discussion was made on the mechanism of the adhesion from the view point of lyopobic and lyopilic colloid mechanism

Small Heat Shock Protein αB-Crystallin Controls Shape and Adhesion of Glioma and Myoblast Cells in the Absence of Stress

<div><p>Cell shape and adhesion and their proper controls are fundamental for all biological systems. Mesenchymal cells migrate at an average rate of 6 to 60 μm/hr, depending on the extracellular matrix environment and cell signaling. Myotubes, fully differentiated muscle cells, are specialized for power-generation and therefore lose motility. Cell spreading and stabilities of focal adhesion are regulated by the critical protein vinculin from immature myoblast to mature costamere of differentiated myotubes where myofibril Z-band linked to sarcolemma. The Z-band is constituted from microtubules, intermediate filaments, cell adhesion molecules and other adapter proteins that communicate with the outer environment. Mesenchymal cells, including myoblast cells, convert actomyosin contraction forces to tension through mechano-responsive adhesion assembly complexes as Z-band equivalents. There is growing evidence that microtubule dynamics are involved in the generation of contractile forces; however, the roles of microtubules in cell adhesion dynamics are not well determined. Here, we show for the first time that αB-crystallin, a molecular chaperon for tubulin/microtubules, is involved in cell shape determination. Moreover, knockdown of this molecule caused myoblasts and glioma cells to lose their ability for adhesion as they tended to behave like migratory cells. Surprisingly, αB-crystallin knockdown in both C6 glial cells and L6 myoblast permitted cells to migrate more rapidly (2.7 times faster for C6 and 1.3 times faster for L6 cells) than dermal fibroblast. On the other hand, overexpression of αB-crystallin in cells led to an immortal phenotype because of persistent adhesion. Position of matured focal adhesion as visualized by vinculin immuno-staining, stress fiber direction, length, and density were clearly αB-crystallin dependent. These results indicate that the small HSP αB-crystallin has important roles for cell adhesion, and thus microtubule dynamics are necessary for persistent adhesion.</p></div