Extracellular Vesicles and Membrane Protrusions in Developmental Signaling.

During embryonic development, cells communicate with each other to determine cell fate, guide migration, and shape morphogenesis. While the relevant secreted factors and their downstream target genes have been characterized extensively, how these signals travel between embryonic cells is still emerging. Evidence is accumulating that extracellular vesicles (EVs), which are well defined in cell culture and cancer, offer a crucial means of communication in embryos.

Preparation and Morphological Analysis of Chick Cranial Neural Crest Cell Cultures.

During vertebrate development, neural crest cells (NCCs) migrate extensively and differentiate into various cell types that contribute to structures like the craniofacial skeleton and the peripheral nervous system. While it is critical to understand NCC migration in the context of a 3D embryo, isolating migratory cells in 2D culture facilitates visualization and functional characterization, complementing embryonic studies. The present protocol demonstrates a method for isolating chick cranial neural folds to generate primary NCC cultures.

Chick cranial neural crest cells release extracellular vesicles that are critical for their migration.

The content and activity of extracellular vesicles purified from cell culture media or bodily fluids have been studied extensively; however, the physiological relevance of exosomes within normal biological systems is poorly characterized, particularly during development. Although exosomes released by invasive metastatic cells alter migration of neighboring cells in culture, it is unclear whether cancer cells misappropriate exosomes released by healthy differentiated cells or reactivate dormant developmental programs that include exosome cell-cell communication. Using chick cranial neural fold cultures, we show that migratory neural crest cells, a developmentally critical cell type and model for metastasis, release and deposit CD63-positive 30-100 nm particles into the extracellular environment.

Age- and sex-specific differences in blood-borne microvesicles from apparently healthy humans.

Background: Sex differences in incidence of cardiovascular disease may reflect age-associated intravascular cellular activation resulting in shedding of cell membrane-derived bioactive microvesicles (MV or microparticles) into the blood. Concentrations of cell-specific MV in blood have the potential to be a diagnostic/prognostic marker of pathology, but ranges of MV must first be established in healthy individuals. This study identified cellular origin of blood-borne MV >0.