Search Results - (Author, Cooperation:C. J. Paige)

2011-12-14

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Bone Marrow Cells/cytology ; Cell Lineage ; Cells, Cultured ; Chimera/immunology ; Citrobacter rodentium/immunology ; Coculture Techniques ; Female ; Germ-Free Life ; Granulocytes/cytology/metabolism ; Immunity, Innate/immunology ; Immunoglobulin A/biosynthesis/*immunology ; Intestinal Mucosa/cytology/immunology ; Intestine, Small/*cytology/*immunology/microbiology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Monocytes/cytology/metabolism ; Nitric Oxide Synthase Type II/biosynthesis/deficiency/metabolism ; Phenotype ; Plasma Cells/*cytology/*immunology/metabolism ; Spleen/cytology ; Stromal Cells/cytology ; Tumor Necrosis Factor-alpha/biosynthesis/deficiency/immunology/metabolism

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The in vitro differentiation of B-lineage progenitors into Ig-secreting mature B cells has classically required a co-culture system containing lipopolysaccharide (LPS) and stromal cells. We have previously showed that B-lineage progenitors cultured in round-bottomed wells can mature and secrete immunoglobulin M (IgM) on par with cultures containing stromal cells. This clearly demonstrates that any factors essential for progenitor cell maturation can be found in cultures containing media, serum, LPS and B-cell progenitors. However, stromal cells are important for the maturation observed when cells are cultured in flat-bottomed wells. We hypothesized that stromal cells may attract B-cell progenitors and promote contacts between responsive cells, a phenomenon that is mimicked by the cultures in round-bottomed wells. In this study, we explore how stromal cells accomplish these functions. We show that stromal cells attract B-cell progenitors in a pertussis toxin-sensitive manner. The stromal cell line S17 produces the chemokine CXCL12, which is able to induce the chemotaxis of B-lineage progenitors. Chemotaxis can be blocked by a small peptide inhibitor (T134) of CXCR4, the CXCL12 receptor. Further, disrupting chemotaxis can reduce the supportive role played by S17 when B-lineage progenitors are cultured in flat-bottomed wells.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The roles of interleukin 2 (IL-2) and gamma interferon (IFN-γ) as direct mediators of B-cell growth and differentiation were analysed. Products of cloned genes were used in both cases. The use of flow cytometric assays coupled with density fractionation of reponding splenic B-cell populations enabled both the characterization of B cells responding to various stimuli and the estimation of their frequency. B cells responding to no-IL-2 related lymphokines promoting growth and differentiation were restricted to low buoyant density fractions. In addition, these cells expressed densities of IL-2 receptor determinants comparable to those found on T cells, although, IL-2 did not support thier growth or differentiation. The inability to demonstrate any direct effect of either IL-2 or IFN-γ on B cells in any state of activation suggests that their physiological roles are mediated through additional cell types.

Electronic Resource

1420-9071

70Z/3 pre-B cells ; poly-A addition site ; post-transcriptional regulation

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract The mouse pre-B cell line, 70Z/3, expresses multiple transcripts of the homeobox gene,HoxB5. We show here that this heterogeneity is due, at least in part, to the usage of alternative poly-A addition sites in the 3′ untranslated region (UT) of the primaryHoxB5 transcript. Furthermore, upon analysis of the subcellular distribution of the differentHoxB5 RNA species, we found that the transcripts are present mainly in the nucleus, with two-to-five-fold less RNA present in the cytoplasm. These studies suggest that multiple post-transcriptional regulatory mechanisms are involved in the expression ofHoxB5 RNA.

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] For homologous recombination, a replacement-type vector (PmlckBSNeo2.3) was constructed (Fig. la) and introduced into D3 embryonic stem cells by electroporation. Six independently targeted embryonic stem cell lines were generated. The average frequency of homologous recombination was about 1 in 2 ...

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] The CD4 molecule is a T-cell-specific surface glycoprotein of relative molecular mass 55,000 (Mr, 55K)11. For homologous recombination, a replacement-type vector (pML3T4Neo) was made (Fig. la). This DNA construct was introduced into D3 embryonic stem (ES) cells by electroporation. Eight ...

Electronic Resource