Metanephric mesenchyme contains multipotent stem cells whose fate is restricted after induction

Area of Science:

• Developmental biology
• Cell biology
• Genetics

Background:

• The mammalian nephron comprises at least fourteen epithelial cell types.
• These diverse cell types originate from the metanephric mesenchyme.
• The cellular composition of the metanephric mesenchyme is not fully understood.

Purpose of the Study:

• To determine if the metanephric mesenchyme contains multipotent stem cells or committed renal cell lines.
• To investigate the differentiation potential of individual renal progenitor cells.

Main Methods:

• Introduction of the lac-Z gene into individual renal progenitors using retroviral-mediated gene transfer.
• Characterization of the differentiated cell types derived from single, lac-Z-tagged metanephric mesenchymal cells after cytodifferentiation.

Main Results:

• The metanephric mesenchyme harbors multipotent stem cells.
• These stem cells can differentiate into at least three distinct epithelial cell types: glomerular, proximal, and distal epithelia.
• The developmental potential of these multipotent cells becomes restricted to a single nephron segment after induction.

Conclusions:

• The metanephric mesenchyme contains multipotent stem cells capable of generating multiple nephron cell lineages.
• Cell fate decisions in renal development involve the restriction of multipotent progenitor potential.
• This study clarifies the cellular origins of nephron diversity.