细胞技术

The RAG-deficient blastocyst complementation system (RBCS) represents a flexible and rapid method for the genetic analysis of lymphocyte function using a gene-targeting approach. In chimeras derived from manipulated embryonic stem cells injected into VDJ recombinationin ...

Differentiation of B lymphocytes can be efficiently obtained when multipotent hematopoietic precursors are cocultured with stromal cell lines and soluble growth factors. Stromal cell lines provide yet-undefined signals required for the expansion of the precursor populati ...

In the past, the life-span of B cells in rodents has been determined by a variety of methods, leading to conflicting results. Among the various techniques employed, labeling of dividing cells with the thymidine analog 5-bromo-2′-deoxyuridine (BrdU) has turned out to be a versatile and reliable pr ...

In the last few years, the effectiveness of developmental and functional studies of individual subsets of cells has increased dramatically owing to the identification of additional subset markers and the extension of fluorescence-activated cell sorter (FACS) capabilities to si ...

In the periphery different populations of B cells can be identified, corresponding to subsequent stages of B-cell development. Transitional 1 B cells are recent bone marrow emigrants traveling with the blood to the spleen. Here they further develop to transitional 2 and mature B cells. Margi ...

This chapter provides information on the application of flow cytometry for analysis of B-cell development, describing in detail the particular surface proteins that can serve as markers for recognizing distinct stages in this process. These cell fractions range from just prior to init ...

Alginic acid is a linear polysaccharide of approx 240 kDa present in the cell walls of the fronds of various seaweeds, including the giant brown kelp (Macrocystis pyrifera), horsetail kelp (Laminaria digitalis), and sugar kelp (L. saccharina). It is a hydrophilic colloidal polyuronic acid co ...

Over the last decade, the use of in vitro production of mammalian embryos and the utilization of assisted reproductive technologies (ART), such as non-surgical embryo transfer, cryopreservation, and intracytoplasmic sperm injection (ICSI), has increased. However, the efficienc ...

Micron-sized fluid channels have been used for biology-related procedures, such as single-cell manipulation (1–3), cell deformation (4,5), cell assays (6), and subcellular molecule positioning (7). Owing to laminar fluid flow on this scale, small volumes of fluid can be precisely contro ...

The important principle of cryopreservation for mammalian embryos is to reduce damage caused by intracellular ice formation. To achieve this goal, two basic approaches were developed: Controlled slow-rate freezing protocols (1). and Vitrification protocols (2).

In the last few years, there has been a significant resurgence of interest in the potential benefits of human oocyte freezing. Essentially, these benefits are formation of donor “egg banks” to facilitate and lessen the cost of oocyte donation for women unable to produce their own oocytes; provis ...

The cytoplasm of oocytes and early embryos is literally the “stuff of life.” The mature mammalian oocyte is an enormous cell invested with all the components required for the initiation of development. Through embryonic cloning scenarios, it is now clear that such cytoplasm is a primary requir ...

Every cell in a mammal, other than odd exceptions (e.g. mature erythrocytes or lymphocytes with rearranged antigen receptors) contains a complete complement of the genetic information required to build another copy of the animal in question. However, the vast majority of adult cells are ter ...

Because of its many favorable characteristics, the zebrafish has become a popular model for studies of vertebrate development (1,2). To further enhance the utility of the zebrafish model for the genetic analysis of embryogenesis, we have been working to establish methods for cell-mediat ...

Zebrafish transgenesis was first demonstrated over 10 yr ago; however, the intensity of technological development has significantly increased in the past few years with the popularity of the zebrafish model. By transgenesis we are referring to germline transgenesis—the introduc ...

Zebrafish (Danio rerio) are a popular vertebrate model system, particularly useful for research in developmental genetics and neurobiology. The adults are easy to obtain and rear; the generation times are only a few months; and large clutches of big embryos are produced (100–1000 per mating). ...

Somatic and germline chimeric chickens are very useful for studying various biological functions of cells, such as immune rejection of donor cells in recipient embryos and chickens, or analyzing the developmental fate of transferred donor cells into recipients. Production of germl ...

The genome of the cat is highly conserved. In fact, of the nonprimate mammalian species in which gene maps are developing, the cat genome exhibits the most similarities to that of the human (1). Biomedical studies in the domestic cat have contributed significantly to our knowledge in the areas of immu ...

For decades, a dream of animal breeders has been to clone (make exact genetic copies of) outstanding animals. This was first achieved by splitting embryos (1); however, with this technique, only a few animals of the same genetic origin could be produced (2). The second approach, which seemed to be more pro ...

Rabbits are widely used as experimental animals in various fields of research. However, unlike mice and rats, rabbits with a homologous genetic background are difficult to obtain, as few inbred strains have been established because of the fact that inbreeding decreases reproductive abi ...