Biomedical Engineering Reference
In-Depth Information
Natural killer
(NK) cell
Neutrophil
Bone
T lymphocytes
Basophil
Lymphoid
progenitor
cell
Eosinophil
B lymphocyte
Hematopoietic
stem cell
Monocyte/macrophage
Multipotential
stem cell
Myeloid
progenitor
cell
Platelets
Red blood cells
Bone (or cartilage)
Hematopoietic
supportive stroma
Marrow
adipocyte
Bone
matrix
Stromal
cell
Osteoblast
Stromal
stem cell
Lining cell
Osteocyte
Blood
vessel
Pericyte
Pre-osteoblast
Skeletal muscle stem cell?
Hematopoietic
stem cell
Hepatocyte stem cell?
Adipocyte
Osteoclast
Figure 1.1
Differentiation of hematopoietic and stromal cells.
(See insert for color representation
of the figure.)
Table 1.3 Proposed cell-surface markers of
undifferentiated hematopoietic stem cells
Mouse
Human
CD34
low/−
CD34
+
SCA-1
+
CD59
+
Thy1
+/low
Thy1
+
CD38
+−
CD38
low/−
C-kit
+
C-kit
−/low
Lin
−
Lin
−
Over the past years, different kinds of surface markers have been used to identify,
isolate, and purify HSCs derived from the bone marrow and the blood. Undifferentiated
HSCs and hematopoietic progenitor cells express c-kit, CD34, and H-2 K. These cells
often lack the Lin lineage marker completely, or only express it at a very low level (Lin
−/
low
). Weissman and his collaborators have focused on surface protein markers of blood
cells from mice and have identified the closest common markers for mouse and human
HSCs. Moreover, it has been demonstrated that the cell surface markers can no longer be
identified during cell development [53]. Indeed, for transplantation purposes, cells that
express the surface proteins CD34
+
, Thy1
+
, and Lin
−
are the most likely to contain stem
cells [54, 55] (Table 1.3).
There are also different sources of HSCs, for example, bone marrow, peripheral blood,
umbilical cord blood, and fetal hematopoietic system. In 1985, Perkins demonstrated
that all major lineages of progenitor cells can be obtained from the bodies of mouse
