细胞技术

Angiogenin is one of several unusual members of the pancreatic ribonuclease superfamily (for reviews see refs. 1,2). It was first isolated as a 14 kDa soluble protein from culture medium conditioned by human colon carcinoma (HT-29) cells, and identified as an angiogenic substance based on its c ...

Restriction endonucleases, which cleave DNA in a site-specific manner, are a fundamental tool of molecular biology. The discovery of endonucleases began in the 1960s and led to commercial availability in the early 1970s. The number of characterized enzymes continues to grow, as does the num ...

Toxins from plants and bacteria have been coupled to antibodies to produce selective cytotoxic agents (immunotoxins) (1–3). However, toxic side effects and immunogenicity have presented major obstacles to the successful clinical application of these proteins (4–9). Production of ...

Currently, there are approx 3000 restriction endonucleases known, recognizing 235 different sequences (1). Although primarily found in bacteria, they also exist in archaea, viruses, and eukaryotes. An estimated 25% of bacteria examined contain at least one restriction endonucle ...

Subcloning can be extraordinarily easy or extremely difficult. The simplest case requires cleavage of the desired fragment from the DNA in which it is located with one or two restriction enzymes, cleavage of the plasmid that will serve as the ultimate recipient with the same enzymes, and ligati ...

DNA-protein interactions are the basis for the molecular mechanisms responsible for nucleic-acid replication, gene transcription, recombination, viral integration, and gene regulation in both normal and pathophysiological conditions. Initially, deletional analys ...

Streptomycetes are mycelial, Gram-positive soil bacteria which produce a variety of biologically active secondary metabolites, including the majority of known antibiotics. In addition to this physiological differentiation, they undergo a complex cycle of morphological d ...

The ribonuclease protection assay (RPA) is a sensitive and straightforward method for detecting, quantitating, and mapping specific mRNA transcripts (5′ and 3′ ends, intron:exon boundaries; 1–6). The method is an adaptation of the S1 nuclease assay (7,8; see also Chapter 31) where RNA, instead ...

Hepatitis C virus (HCV) contains a positive-sense, single-stranded RNA viral genome that encodes viral structural and nonstructural proteins (1). Initiation of translation is under control of the internal ribosome entry site (IRES) located within the viral 5′-nontranslated regi ...

Embryonic stem (ES) cells have the potential to differentiate into all cell types originating from the three germ layers; however, there are still few reports about the formation of functional organs from embryonic stem cells. Recently, we reported that by hanging drops of mouse ES cells, embry ...

Vascular endothelial cells or endothelial progenitor cells derived from stem cells could potentially lead to a variety of clinically relevant applications, including cell-based therapies and tissue engineering. Embryonic stem (ES) cells serve as an excellent in vitro system for s ...

Embryonic stem (ES) cells are pluripotent cells derived from blastocyst-stage embryos. They are characterized by their infinite self-renewal capacity and their ability to differentiate into many cell types in vitro as well as in vivo. The present protocol describes culture conditio ...

The development of techniques for the in vitro differentiation of mouse embryonic stem (ES) cells has provided researchers with the tools to investigate vascular development as would occur in an early embryo. Mice lacking the vascular integrins have various defects in the vasculature, i ...

The roles of the transforming growth factor (TGF)-β superfamily in vasculogenesis have been implicated by the findings that mutations in genes encoding for various TGF-β superfamily signaling components exhibit defects in vascular tissues in humans and mice. Embryonic stem cell (ES ...

Embryonic stem (ES) cells represent an attractive tool not only for the study of the development of various cell types but also as a potential source of cells for transplantation. Previous studies suggested a role of the signal transduction protein SRC homology 2(SH2) protein of Beta-cells (SHB) ...

Embryonic stem (ES) cells represent a potential source of transplantable cells for the treatment of diabetes because of their almost unlimited proliferation capacity and the potential to differentiate into insulin-producing cells. The differentiation conditions signifi ...

Currently, there is no effective treatment for photoreceptor degeneration, the most common cause of blindness caused by diseases like retinitis pigmentosa, age-related macular degeneration, and diabetic retinopathy. Two promising approaches include cell therapy to replace ...

From a therapeutic perspective on liver, the use of embryonic stem (ES) technology in the generation of a large number of high-functional hepatocytes developed from ES cells for cell transplantation is anticipated. We have explored a three-dimensional culture system in which hepatocy ...

During normal embryogenesis, embryonic stem cells (ESCs) reside in the context of complex three-dimensional tissue structures, in particular of extracellular matrices (ECMs), which determine cell migration, proliferation, and differentiation. Therefore, to study ESC diff ...

For cell replacement therapies of retinal diseases, the most-needed cells are retinal pigment epithelial cells and photoreceptor cells; lens cells are needed for replacement of the cataract. Stromal cell-derived inducing activity induces the differentiation of mouse embryon ...