PUBLICATION

Early hematopoiesis and developing lymphoid organs in the zebrafish

Authors
Willett, C.E., Cortes, A., Zuasti, A., and Zapata, A.G.
ID
ZDB-PUB-990414-60
Date
1999
Source
Developmental Dynamics : an official publication of the American Association of Anatomists   214: 323-336 (Journal)
Registered Authors
Willett, Catherine
Keywords
zebrafish development; hematopoiesis; thymus; kidney
MeSH Terms
  • Animals
  • Epithelial Cells/metabolism
  • Heart/embryology
  • Hematopoiesis*
  • Kidney/embryology*
  • Leukopoiesis
  • Thymus Gland/embryology*
  • Time Factors
  • Zebrafish/embryology*
PubMed
10213388 Full text @ Dev. Dyn.
Abstract
In zebrafish, the transparent and rapidly developing embryo and the potential for genetic screening offer a unique opportunity to investigate the early development of the vertebrate immune system. Here we describe the initial appearance of various blood lineages and the nature of accumulating hematopoietic tissue in the thymus and kidney, the main lymphoid organs of adult teleosts. The ultrastructure of the first site of hematopoiesis, the intermediate cell mass (ICM), is described from the 5-somite stage, about 11.5 hours post-fertilization (hpf) until 24 hpf. The ICM gives rise to the primitive erythroid lineage, which accounts for all circulating erythrocytes for the first 4 days pf. From 24 to 72 hpf, a few developing granulocytes are seen close to the yolk sac walls and in the caudal axial vein. The heart, previously proposed as an early blood-forming organ in zebrafish, did not contain hematopoietic cells. The thymic primordium, consisting of two layers of epithelial cells, appears at 60 hpf. By 65 hpf, it is colonized by immature lymphoblasts. The thymus gradually accumulates lymphocytes, and the lymphocytes and epithelial cells progressively differentiate for 3 weeks pf. At 96 hr, the pronephros contains hematopoietic cells, mainly developing erythrocytes and granulocytes. The amount of renal hematopoietic tissue increases rapidly; however, lymphocytes were not detected until 3 weeks pf.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping