Multiparameter flow cytometry characterization of MHC class I negative mouse bone marrow cells

Area of Science:

• Hematology
• Stem Cell Biology
• Immunology

Background:

• MHC-I down-regulation is observed in fetal liver progenitors and specific adult bone marrow stem cell subsets.
• Bone marrow derived liver stem cells (BMDLSC) and multipotent adult progenitors (MAPC) are two such subsets capable of differentiating into hepatocytes.
• The study aimed to characterize the MHC-I negative bone marrow compartment in relation to BMDLSC and MAPC.

Purpose of the Study:

• To characterize the MHC-I negative bone marrow compartment.
• To investigate the relationship between MHC-I expression and stem cell markers in BMDLSC and MAPC.

Main Methods:

• Multiparameter flow cytometry was used to analyze the MHC-I negative bone marrow compartment in adult mice.
• Hematopoietic (CD45, Ter119) and stem cell markers (Thy1.2, c-Kit, IL-3R, CD34) were utilized.
• Analysis focused on identifying distinct subpopulations within the MHC-I negative bone marrow compartment.

Main Results:

• The MHC-I negative bone marrow compartment segregated into four subpopulations based on CD45 and Ter119 expression.
• Stem cell markers were predominantly expressed on MHC-I negative/CD45+/Ter119- cells.
• In vivo, multipotent adult progenitors (MAPC) comprised both MHC-I negative and positive cells and did not express tested stem cell markers.

Conclusions:

• Mouse BMDLSC and MAPC represent distinct stem cell populations.
• Down-regulation of MHC-I is a shared characteristic between BMDLSC and MAPC.
• Selecting MHC-I negative cells may be an effective strategy for enriching bone marrow stem cells with liver developmental potential.