mortality/aging
• a single live-born pup was pale, runt, in obvious respiratory distress, and died within 15 minutes of birth
|
• all delivered embryos (6%) are stillborn, with a single exception that died within 15 minutes of birth
|
• homozygous embryos die steadily across a wide developmental span from ~E10.5 until birth
|
growth/size/body
• concentric hypertrophy of the cardiac ventricular wall at E19.5, suggesting increased vascular resistance
|
• average gestational age-adjusted weight of live embryos is ~20% below that of wild-type controls
|
• some of the embryos euthanized at E13.5 to E19.5 appear runted
|
• embryos appear growth restricted
|
embryo
• placentas appear thinner and poorly developed at E19.5
• a striking number of microcalcifications are seen along the giant cell and spongiotrophoblastic layers, suggesting placental distress
|
• poorly formed maternal vascular spaces at E19.5
|
• collapse of the labyrinth reduces placenta thickness at E19.5
|
immune system
• a severely hypoplastic spleen is often seen at E19.5
|
• significant B-cell lymphopenia at E13.5 and E19.5
|
• a severely hypoplastic spleen is often seen at E19.5
|
• marked underdevelopment of lymphoid tissues at E19.5
|
cardiovascular system
• concentric hypertrophy of the cardiac ventricular wall at E19.5, suggesting increased vascular resistance
|
• the thin-walled capillary bed of fetal circulation is ill defined
|
hemorrhage
(
J:229985
)
• some of the embryos euthanized at E13.5 to E19.5 are hemorrhagic
|
liver/biliary system
small liver
(
J:229985
)
• embryonic livers are often small
|
pale liver
(
J:229985
)
• embryonic livers are often pale
|
hematopoietic system
• a severely hypoplastic spleen is often seen at E19.5
|
• variable, multi-lineage hematopoietic deficiency at E13.5 and E19.5, with deficits in erythroid, granulocyte/macrophage, and lymphoid lineages, as shown by immunophenotyping of fetal liver cells and colony-forming assays
|
• bone marrow hypoplasia at E19.5
|
• significantly decreased number of hepatic megakaryocytes at E19.5
|
• significant B-cell lymphopenia at E13.5 and E19.5
|
• rarefaction of hepatic and bone marrow hematopoietic precursors across all lineages at E19.5, suggesting impaired hematopoiesis
• significantly reduced numbers of hematopoietic progenitor cells at E13.5 and E19.5, as shown by colony-forming assays
|
• a severely hypoplastic spleen is often seen at E19.5
|
• despite normal or even increased numbers of hematopoietic stem cells (HSCs), transplantation of mutant HSCs into lethally irradiated mice fails to reconstitute hematopoiesis
|
respiratory system
small lung
(
J:229985
)
• markedly small lungs at E19.5
|
• marked lung hypoplasia at E19.5
|
• broad, thick-walled terminal sacs lined by primarily bronchial-type cuboidal epithelium at E19.5
|
• reduced branching of air spaces at E19.5
|
nervous system
• marked brain parenchymal hypercellularity at E19.5
|
• cerebral hyperplasia at E19.5
|
• reduced organization of layers I to VI of the diencephalic cortex with less distinct cortical layering at E19.5
|
• no cerebellar lobations are present at the level of the choroid plexus in the IV ventricle at E19.5
|
integument
endocrine/exocrine glands
• a severely hypoplastic spleen is often seen at E19.5
|