Structurally distinct endocytic pathways for B cell receptors in B lymphocytes

Distinct Pathways of B Cell Differentiation

Phenotypically distinct B cell development pathways map to the three B cell lineages in the mouse.

A recent article by Montecino-Rodriguez et al. [Montecino-Rodriguez, E., Leathers, H. & Dorshkind, K. (2006) Nat. Immunol.7, 293-301] has distinguished the early progenitors for B-1 cells, which principally develop in neonates, from early progenitors for B-2 cells, which principally develop in adult bone marrow. Here we introduce syndecan-1 (CD138) and MHC class II (I-A) as markers of early B c...

Two Distinct Pathways of B-Cell Development in Peyer’s Patches

The developmental biology of sheep ileal and jejunal Peyer's patches (PP) was investigated using corticosteroids to deplete immature B lymphocytes. During a 7-day treatment with dexamethasone, ileal PP follicular (iPf)B-cell proliferation was arrested and most iPfB-cells died. This resulted in follicular involution with the survival of mesenchymal cells. No iPfB-cell proliferation was detected ...

Distinct Dynamin-dependent and -independent Mechanisms Target Structurally Homologous Dopamine Receptors to Different Endocytic Membranes

D1 and D2 dopamine receptors are structurally homologous G protein-coupled receptors that serve distinct physiological functions both in neurons and nonneural cell types. We have observed that these receptors are selectively endocytosed in HEK293 cells by distinct dynamin-dependent and -independent mechanisms. Although these endocytic mechanisms operate with similarly rapid kinetics, they diffe...

Revising B Cell Receptors

B cell development is often portrayed as a series of decision points that expand an antigen-reactive cell to a clone producing a single antibody. This is hardly the case: B cell development is dependent on a series of error-prone, random rearrangement events that through ongoing diversification reach a compromise in which most cells are not au-toreactive (except in disease) and the majority of ...