细胞功能测定

B-lymphopoiesis in vivo is a very complex process that is influenced by cooperation between cells, cytokines, and other receptor-ligand interactions, which developmentally occur at different cellular stages. Various in vitro models have been very useful in unraveling this complex ...

A chicken DT40 B-cell line provides an excellent model system for the analysis of the function of genes related to B-cell antigen receptor (BCR) signaling. Crosslinking of BCR by �-chain-specific antibody stimulates DT40 cells to undergo apoptosis. Activation of protein-tyrosine kina ...

Over the past 15 yr, the use of transgenic mice has led to significant advances in our understanding of immunological tolerance. In a normal repertoire the number of B cells with a single antigen receptor specificity is very small, making the study of their fate difficult. In contrast, animals that ca ...

Recent advances in cell biology have provided evidence that the plasma membrane is not a homogeneous lipid bilayer but rather contains within it sphingolipid- and cholesterol-rich membrane microdomains, termed lipid rafts, which serve as platforms for both receptor signaling and tr ...

Signal transduction by the B-cell antigen receptor (BCR) regulates development, survival, and clonal expansion of B cells. The BCR complex comprises the membrane-bound immunoglobulin molecule and the Ig-α/Ig-β heterodimer, and was shown to form oligomeric structures. Antigen-me ...

Helper T-cell-regulated B-cell memory develops in response to initial antigen priming as a cellular product of the germinal center (GC) reaction. On antigen recall, memory response precursors expand rapidly with exaggerated differentiation into plasma cells to produce the high-t ...

The development and functional activities of B lymphocytes critically depend on their migratory capacity. Both in vitro and in vivo assays can be used to assess the migratory ability of B cells. Filter-based transwell assays measure both spontaneous and chemoattractant-induced cell m ...

During an immune response, B lymphocytes can switch expression of immunoglobulin (Ig) class (isotype) from IgM to IgG, IgE, or IgA. This Ig class switch is based on a deoxyribonucleic acid (DNA) recombination event that results in an exchange of the gene segments coding for the constant region of the Ig ...

Primary murine splenic B cells can be cultured ex vivo and, following treatment with LPS, cytokines and/or CD40L proliferate, and undergo class switch recombination and terminal differentiation to become immunoglobulin-secreting plasmacytic cells. Methods are described here ...

To determine whether an immune system is able to support T-cell-dependent affinity maturation one needs antigens that induce well-characterized immune responses. This chapter describes the response of the BALB/c mouse to hapten 2-phenyl-4-ethoxymethylene-oxazolone (phOx) c ...

This chapter describes the analysis of long- and short-lived plasma cells on tissue sections. Mice are immunized with 4-hydroxy-3-nitrophenyl acetyl (NP) coupled to a T-cell-dependent carrier. Antigen-specific germinal center cells and extrafollicular plasma cells are identi ...

Since its first application in mice almost 10 yr ago, the Cre/loxP has become the system of choice to study gene function in vivo in a cell-type, stage-specific, and inducible manner. This chapter provides a set of updated protocols that will help the reader to construct a vector for conditional gene tar ...

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 ...