Appendix K. 
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Reports have indicated that mammary stem cells also exist. 
Isolated cells from mouse could be propagated in vitro and 
differentiated into all three mammary epithelial lineages. Clonally- 
propagated cells were induced in culture to generate complex three- 
dimensional structures similar to that seen in vivo. Transcriptional 
profiling indicated that the mammary stem cells showed similar gene 
expression profiles to those of bone marrow stem cells. In that 
respect, there is a report that human and mouse mammary stem cells 
exist as a side population, as seen for bone marrow, liver, and muscle 
stem cells. When propagated in culture, the isolated mammary 
side population stem cells could form epithelial ductal structures. 
SALIVARY GLAND 
A recent report indicates that stem cells can be isolated by 
limiting dilution from regenerating rat salivary gland and propagated 
in vitro.^^^ Under differing culture conditions, the cells express genes 
typical of liver or pancreas, and when injected into rats can integrate 
into liver tissue. 
SKIN 
Multipotent adult stem cells have been isolated from the 
dermis and hair follicle of rodents. The cells play a role in 
maintenance of epidermal and hair follicle structures, can be 
propagated in vitro, and clonally isolated stem cells can be induced 
to form neurons, glia, smooth muscle, and adipocytes in culture. 
Dermal hair follicle stem cells have also shown the abihty to reform 
the hematopoietic system of myeloablated mice.^^® 
TENDON 
A recent report notes the isolation of established stem cell- 
like lines from mouse tendon. The cells exhibited a mesenchymal 
morphology, and expressed genes related to osteogenic, 
chondrogenic, and adipogenic potential, similar to that seen in bone 
marrow mesenchymal stem cells. 
SYNOVIAL MEMBRANE 
Stem cells from human synovial membrane (knee joint) have 
been isolated which show multipotent abilities for differentiation, 
including evidence of myogenic potential. These stem cells were 
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