细胞技术

Part A. Production of Hybridoma Cell Lines A strategy for raising monoclonal antibodies involves immunization of mice; fusion of the mouse spleen cells with a myeloma cell line; selection, cloning, and freezing of hybridoma cell lines; and screening for monoclonal antibody production. P ...

Purification of membrane proteins of necessity requires the use of detergents to solubilize the proteins prior to their isolation. Although reconstitution of membrane proteins has been achieved without the use of detergents (e.g., by sonication of membrane proteins with lipids), det ...

Protein-protein interactions in biological membranes can be studied using conventional chemical crosslinking methods, crosslinked products being detected either by altered molecular weights on SDS-polyacrylamide gels or using specific antibodies. Unfortunately, ...

Interactions between lipids and proteins have been studied using a variety of spectroscopic methods. Nuclear magnetic resonance (usually using deuterated phospholipid) can give information about conformational changes of lipid molecules on binding to membrane proteins, b ...

The basic principle for probing the transverse distribution of membrane lipids is simple. Lipids that are available for modification by enzymes or for covalent labeling in impermeable membrane vesicles are considered to be in the outer leaflet of the membrane bilayer, and those that are also ...

The transforming growth factor-β (TGF-β) pathway is important in the growth control of many different cell types, particularly epithelial cells, and is often disrupted in the development of cancer (1,2). The most common mutation in the TGF-β pathway detected thus far is mutation of the type II rec ...

The mitogen-activated protein kinase (MAPK) superfamily includes three major subfamilies: extracellular signal-regulated kinase (Erks), c-Jun-N-terminal kinases (JNKs)/stress-activated protein kinases (SAPKs), and p38 kinases (1–3). Activation of MAPK requires the p ...

The transforming growth factor-β (TGF-β) pathway is important in the growth control of many different cell types, particularly epithelial cells, and is often disrupted in the development of several different types of cancer. Many tumor cell lines are resistant to the growth suppressive ef ...

Transforming growth factor-β (TGF-β) is an important regulator of cellular growth and immune homeostasis (1–3). TGFβ is a homodimeric 25-kDa protein which activates cellular signaling through the recruitment and transphos-phorylation of specific heterodimeric cell-surfa ...

Transforming growth factors (TGFs) were initially isolated from the conditioned medium of transformed cell lines through their ability to stimulate anchorage-dependent cells to form colonies in soft agar (1,2). The ability to proliferate in an anchorage-independent manner is sti ...

The transforming growth factors-β (TGF-βs) constitute a family of potent regulators of cellular differentiation, proliferation, migration, and protein expression (1,2). Three isoforms of TGF-β have been described in mammals: TGF-β1, 2, and 3 (3–5). Most cell lines and tissues secrete TGF-β ...

Radioiodinated transforming growth factors ( TGF-βs) are critical reagents for functional studies on TGF-β ligand-receptor binding (1–5), TGF-β-binding protein interactions (6–9), ligand uptake, degradation and clearance (1,10,11), titering of TGF-β neutralizing antibodi ...

Transforming growth factor-β1 (TGF-(β1) is a 25-kDa homodimeric protein secreted by numerous cells including platelets, monocytes, macrophages, epithelial cells, and fibroblasts (1–3). Active TGF-(β1 exerts multiple and divergent effects on mesenchymal and epithelial cell cy ...

Coordinated regulation of production and turnover of extracellular matrix (ECM) components is essential for normal tissue homeostasis. The composition of the extracellular matrix can influence cell growth, state of differentiation, and specific gene induction. The multifu ...

Signaling by transforming growth factor-(β superfamily members is initiated when ligand binds to and induces formation of a heteromeric receptor complex composed of type I and type II serine/threonine kinase receptors (reviewed in refs. 1–4). Upon formation of this complex, receptor II p ...

The activator protein-1 (AP-1) transcriptional complex is composed of DNA binding proteins belonging to the Jun and Fos proto-oncogene families, which play an important role in cell proliferation and transformation (reviewed in ref. 1). AP-1 activity is required to stimulate many genes t ...

The tranforming growth factor β (TGF-β ) family of cytokines participates in regulating cell growth, morphogenesis, and differentiation by modulating expression of a variety of genes (1–4). These gene products broadly cover proteins involved in deposition of an extracellular matrix ...

The chemical mutagenesis of mouse embryonic stem (ES) cells is an approach complementary to chemical mutagenesis of spermatogonia in whole animals. It has great potential to contribute significantly to the generation of a comprehensive collection of multiple alleles for most mamma ...

Cell fusion is a powerful tool for understanding the molecular mechanisms of epigenetic reprogramming. In hybrid cells of somatic cells and pluripotential stem cells, including embryonic stem (ES) and embryonic germ cells, somatic nuclei acquire pluripotential competence. ES and ...

Stem cells raise the possibility of regenerating failing body parts with new tissue. Before stem cells can safely fulfill their promise, many technical problems, including understand-ing the stem cell phenotype, must be overcome. DNA methylation, which is responsible for gene silenc ...