Human term placenta as a source of hematopoietic cells.
Level 5 - mechanism / opinion, no new human data
Preclinical laboratory tissue study and xenograft animal model.
PubMed 19429852 · doi:10.3181/0809-BC-262
What was done
Researchers evaluated human term placental tissue to determine if it contains hematopoietic stem and progenitor cells, established protocols for processing and cryopreserving these cells, and tested their functionality via in vitro colony-forming assays (erythroid and myeloid) and in vivo xenotransplantation into immunodeficient mice.
What was found
Human placental tissue contained large quantities of CD34-expressing hematopoietic cells, providing an estimated cellular yield several-fold greater than typical umbilical cord blood collections. Both fresh and cryopreserved placental cells generated erythroid and myeloid colonies in vitro and reconstituted lymphoid cells following transplantation into immunodeficient mice. The abstract reports no exact numerical values, sample sizes, or statistical metrics.
Why it matters
Umbilical cord blood transplantation is frequently constrained by low total cell doses for adult recipients; identifying the placenta as a rich, cryopreservable source of functional hematopoietic progenitors offers a potential strategy to expand cell yields for allogeneic transplantation.
Limits
This is entirely preclinical bench and animal work; clinical utility, safety, and long-term multilineage reconstitution in human recipients were not evaluated. The abstract omits sample sizes (number of human placentas and mice evaluated), exact cell yields, quantitative comparison metrics, and engraftment efficiency rates.
Cited by
- supports Dr. Frans Kuypers' laboratory developed a technique that retrieves between 5 and 7 times more hematopoietic stem cells from the placenta than from umbilical cord blood.
- supports Frans Kuypers published papers in 2009 and 2012 demonstrating that cells isolated from human term placenta can be cultured to differentiate into multiple cell types such as neurons and heart cells.