The puzzling origin of lymphocytes

Sanford-Burnham Medical Research Institute.
Blood (Impact Factor: 10.45). 06/2012; 119(24):5609-10. DOI: 10.1182/blood-2012-04-420737
Source: PubMed


In this issue of Blood, Yoshimoto et al show that yolk sac (YS) and para-aortic splanchnopleura (P-Sp) cells, early in development, can generate both adult and fetal type T lymphocytes. The most remarkable conclusion is that T lymphocytes are derived directly from the hemogenic endothelium, before the appearance of hematopoietic stem cells.

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