Lymphocyte-vascular adhesion protein-2 was recently identified as CD73. The CD73 molecule, otherwise known as ecto-5'-nucleotidase, is a lymphocyte maturation marker that is involved in intracellular signaling, and lymphocyte proliferation and activation. We now show that CD73, in addition to mediating lymphocyte binding to endothelial cells, also mediates adhesion between B cells and follicula...

B lymphocytes undergo affinity maturation of their antigen receptors within germinal centers. These anatomical structures develop in secondary lymphoid organs from the clonal expansion of a few antigen-specific founder B cells, whose isolation and characterization are reported here. Human germinal center founder cells express the naive B cell markers surface IgM and IgD as well as the germinal ...

BACKGROUND AND PURPOSE This study examines the role of thrombin's protease-activated receptor (PAR)-1, PAR-4 in mediating cyclooxygenase-2 and mammalian target of rapamycin after germinal matrix hemorrhage. METHODS Germinal matrix hemorrhage was induced by intraparenchymal infusion of bacterial collagenase into the right ganglionic eminence of P7 rat pups. Animals were treated with PAR-1, PAR...

The generation of robust T-cell-dependent humoral immune responses requires the formation and expansion of germinal center structures within the follicular regions of the secondary lymphoid tissues. B-cell proliferation in the germinal center drives ongoing antigen-dependent selection and the generation of high-affinity class-switched plasma and memory B cells. However, the mechanisms regulatin...

Germinal centers are critical for affinity maturation of antibody (Ab) responses. This process allows the production of high-efficiency neutralizing Ab that protects against virus infection and bacterial exotoxins. In germinal centers, responding B cells selectively mutate the genes that encode their receptors for antigen. This process can change Ab affinity and specificity. The mutated cells t...

The development of germinal centres in the spleen has been estimated in a series of 266 children dying in hospital and 205 children presenting as unexpected death in infancy. The prevalence of germinal centres in the spleen increases rapidly after birth. The percentage of Malpighian bodies showing germinal centres in the spleen is greater in all categories of our classification of death in chil...

A previous study of 70 cases of thymoma described in 1966 by the author1 reported that definite germinal centers were found in the normal thymic tissue attached to one case of thymoma associated with myasthenia gravis, and that this was very interesting from the point of view of whether thymoma or thymic germinal center was a more important occurrence of a myasthenic condition. Since then routi...

At the turn of the twentieth century, Edmund B. Wilson performed experiments to show where germinal matter was located in molluscs. At Columbia University [4] in New York City, New York, Wilson studied what causes cells to differentiate during development. In 1904 he conducted his experiments on molluscs, and he modified the theory about the location of germinal matter in the succeeding years. ...

BACKGROUND AND PURPOSE The volumetric changes of the ventricular system and germinal matrix are important to understand brain maturation and the mechanism of subependymal hemorrhage. Our purpose was to show the 3D configuration of the brain, germinal matrix, and lateral ventricles and to discuss the volumetric changes of each structure with maturation by using high-resolution MR imaging. METH...

The proliferation of cells in the germinal zone of the optic tectum of adult goldfish was studied following unilateral optic nerve crush or removal of one eye. Dividing germinal cells were labeled with [3H]thymidine, which was injected at various times (0 to 30 days) following surgery; fish were sacrificed after short (48 hr) survival times. The numbers of labeled nuclei in the tectal germinal ...