概要：OP9, a macrophage-derived embryonic stem cell line, was isolated from the stroma of a mouse embryo.
With their fibroblast-like morphology and origin from the bone marrow stromal cells, OP9 cells have proven to be instrumental in advancing our understanding of cell therapy, regenerative medicine, and immunomodulation.
It shares an identical immunophenotype with standard mouse mesenchymal stem cells (MSCs).
The cell line was cultured from the newborn calvaria of osteopetrosis mutant mice, which lack functional macrophage colony-stimulating factor (M-CSF).
Specific markers such as CD140a+, CD140b+, ?-SMA+, and Calponin+ suggest a perivascular origin for these cells.
Morphologically, OP9 cells exhibit a distinct bipolar, fibroblast-like appearance.
Their characteristics have been extensively studied using immunofluorescence staining and flow cytometry.
Notably, the absence of markers such as CD45, CD11b, Flk-1, CD31, and CD34 confirms their non-hematopoietic and non-endothelial identity.
OP9 cells can expand mouse mesenchymal stem cells (MSCs) in vitro, facilitating the study of MSCs biological features.
Their mesenchymal potential has been confirmed through successful differentiation when cultured in an adipogenic medium.
When co-cultured with ES cells, OP9 cells enhance the hematopoietic supportive capacity of hemogenic precursors and progeny.
Co-culturing ESC with OP9 cells triggers a cascade of events, ultimately leading to the development of various lineages of blood cells.
This enables the study of hematopoietic cell differentiation from MSCs, including B cell lineages, erythrocytes, lymphocytes, and megakaryocytes.
Furthermore, OP9 cells promote the production of hematopoietic progenitors when multipotent germline stem cells (mGS) are differentiated on their surface.
In addition, OP9 cells have demonstrated their ability to facilitate the differentiation of MSCs into osteocytes, chondrocytes, myocytes, tenocytes, and adipocytes.
Their migration can be prompted by using growth factors such as bFGF, IGF-1, IL-3, PDGF-BB, TGF-?1, and TGF-?3.
However, while OP9 cells offer great promise, there are certain limitations to consider.
Since OP9 cells are not an immortalized cell line, the primary cell culture of OP9 cells can only be utilized for short-term, small-scale projects, as it has a limited lifespan of approximately one month.
