Xenopus laevis is the model of choice for evolutionary, comparative, and developmental
studies of immunity, and invaluable research tools including MHC‐defined clones, inbred …

We provide a comparative analysis of the expression patterns and ventral mesoderm‐
inducing properties of Xenopus BMP‐2 and BMP‐4. Transcripts for BMP‐2 and BMP‐4 are …

The adult hematopoietic system of mammals is a dynamic hierarchy of cells with the
hematopoietic stem cell at its foundation. During embryonic development, the source and …

The precise time of appearance of the first hematopoietic stem cell activity in the developing
mouse embryo is unknown. Recently the aorta-gonad-mesonephros region of the …

IT is widely accepted that during murine embryogenesis, totipotent haematopoietic stem
cells first originate in the yolk sac, then migrate to the fetal liver and finally colonize the bone …

Hematopoietic stem cells (HSCs) are responsible for generating all the lineages of the
blood. During vertebrate development, waves of hematopoietic activity can be found in …

Haematopoietic stem cells (HSCs) are tissue-specific stem cells that replenish all mature
blood lineages during the lifetime of an individual. Clinically, HSCs form the foundation of …

The hematopoietic system of vertebrates is derived from the mesodermal germ layer in early
embryogenesis. Various animal models have been used for the study of hematopoiesis …

Whether embryonic and adult blood derive from a single (yolk sac) or dual (yolk sac plus
intraembryonic) origin is controversial. Here, we show, in Xenopus, that the yolk sac (VBI) …

Vertebrate embryonic blood formation is regulated by factors that participate in dorsal-
ventral patterning and mesoderm induction. The GATA-binding transcription factors are …