Validation and use of a computer-assisted counting procedure to quantify BrdU-labeled proliferating cells in the early postnatal mouse hippocampus.

The dentate gyrus is one of the few brain regions that show proliferation of neuronal precursors postnatally and in adult life. Proliferation in the dentate gyrus has been shown to be influenced by exercise, stress and drugs such as antidepressants. Traditionally, proliferation studies rely on the time consuming and subjective manual count of labeled cells.

5-hydroxytryptamine induces mast cell adhesion and migration.

The neurotransmitter serotonin (5-hydroxytryptamine (5-HT)) is implicated in enhancing inflammatory reactions of skin, lung, and gastrointestinal tract. To determine whether 5-HT acts, in part, through mast cells (MC), we first established that mouse bone marrow-derived MC (mBMMC) and human CD34(+)-derived MC (huMC) expressed mRNA for multiple 5-HT receptors. We next determined the effect of 5-HT on mouse and human MC degranulation, adhesion, and chemotaxis.

High and low affinity carbohydrate ligands revealed for murine SIGN-R1 by carbohydrate array and cell binding approaches, and differing specificities for SIGN-R3 and langerin.

The number of receptors of the 'C-type' lectin family is greater than previously thought with a considerable proportion on cells (dendritic cells and macrophages) critical for innate immunity. Establishing that they bind carbohydrates, unravelling and comparing details of their ligands is crucial for understanding the molecular basis of the cell-cell and cell-pathogen interactions that they mediate. Here we use carbohydrate arrays as a new approach to discovering the ligands of three recently described C-type lectin-type receptors on antigen-presenting cells: murine SIGN-R1, SIGN-R3 and langerin.

The C-type lectin SIGN-R1 mediates uptake of the capsular polysaccharide of Streptococcus pneumoniae in the marginal zone of mouse spleen.

SIGN-R1, a recently discovered C-type lectin expressed at high levels on macrophages within the marginal zone of the spleen, mediates the uptake of dextran polysaccharides by these phagocytes. We now find that encapsulated Streptococcus pneumoniae are rapidly cleared by these macrophages from the bloodstream, and that capture also takes place when different cell lines express SIGN-R1 after transfection. To assess the role of the capsular polysaccharide of S.

SIGN-R1, a novel C-type lectin expressed by marginal zone macrophages in spleen, mediates uptake of the polysaccharide dextran.

The marginal zone macrophages of the spleen are implicated in the clearance of polysaccharides, but underlying mechanisms need to be pinpointed. SIGN-R1 is one of five recently identified mouse genes that are homologous to human DC-SIGN and encode a single, external, C-terminal C-type lectin domain. We find that a polyclonal antibody to a specific SIGN-R1 peptide reacts primarily and strongly with a subset of macrophages in the marginal zone of spleen and lymph node medulla.