Mesenchymal Stem Cell Markers
In general, stem cells are specialized cells capable of self-renewal through cell division with the capability to differentiate into multi-lineage cells.
Mesenchymal stem cells (MSCs) are tissue stem cells. They are ‘multipotent’, implying that they can differentiate into more than one cell type in the body.
Friedenstein et al. first discovered MSCs in bone marrow1. Decades of studies have offered significant in-depth understanding of these cells.
Efficient population of MSCs has been reported from, but not limited to, bone marrow2. For example, cells which exhibits characteristics of MSCs have been isolated from adipose tissue3,4, amniotic fluid5,6, dental tissues7, endometrium8, menstrual blood9, peripheral blood10, placenta and fetal membrane11.

Figure 1: Schematic representation of mesenchymal stem cells (MSCs) differentiation from bone marrow.
Mesenchymal stem cells can be defined by the combination of different surface markers protein like NT5E/CD73, THY1/ CD90 and, ENG/CD105.

Figure 2: Immunohistochemical staining of Endoglin/CD105 in the human blood vessels using Anti-ENG monoclonal antibody (AMAb90925).
Connective Tissue Cells (Fibroblasts)
Fibroblasts or connective tissue cells (also known as stromal cells) provide support and structure for the different organs. Among other things, they also play an essential role in the production, maintanance and remodeling of the extracellular matrix.

Figure 3: Immunohistochemical staining of Serpin Peptidase Inhibitor, or Heat Shock Protein 47, in the human esophagus using Anti-SERPINH1 polyclonal antibody (HPA029198).
Cartilage Cells (Chondrocytes)
Chondrocytes are primarily mesodermal in origin and are the sole cellular constituents of normal cartilaginous tissue. Chondrocytes are responsible for the synthesis of the two major constituents of the matrix (collagens and proteoglycans) and enzymes that degrade matrix components. Hence the chondrocyte plays a key role in the regulation of cartilage synthesis and degradation.
Differentiation of MSCs into chondrocytes is regulated by transcription factors like SOX9.
White Fat Tissue Cells (Adipocytes)
Adipocytes are highly specialized cells that play an essential role in the energy expenditure of most vertebrates. Adipocytes convert excess energy to fat and deposit it during feeding in preparation for periods of food deprivation. They have a distinct “signet-ring” morphology containing one or more large triglyceride (fat) droplets, which distinguish them from the lipid-deficient stromal/vascular cells.
Figure 4 shows immunohistochemical staining for PLN1 (perilipin 1) which is a marker for adipocytes.

Figure 4: Immunohistochemical staining of human breast for Perilipin-1 using Anti-PLIN1 polyclonal antibody (HPA024299).
Muscle Cells
(Smooth, Cardiac, Skeletal)
A myocyte is the functional cell type of muscle tissue. There are three different types of myocytes with distinct properties. These are restricted to smooth, cardiac and skeletal muscle cells.
Smooth muscle cells (SMC) build up involuntarily controlled, non-striated muscles occuring in the walls of visceral tissues and blood vessels. The master regulation of smooth muscle gene expression is mediated by myocardin.
Cardiomyocytes or heart muscle cells are involuntarily controlled striated cells confined to the heart. Cardiomyocytes are among other factors regulated by GATA4 and myocardin.
Skeletal muscle cells are striated muscle cells under voluntary control and are attached to the skeleton by tendons. MyoD1 is a key regulator of skeletal (striatal) muscle cell differentiation.
Figures 5-7 show immunostainings examplifying specific antibody markers for each type of muscle cell.

Figure 5: Immunohistochemical staining of smooth muscle cell (SMC) showing high expression of Transgelin using Anti-TAGLN polyclonal antibody (HPA019467).

Figure 6: Immunohistochemical staining of cardiac muscle cell showing high expression of Fatty Acid Binding Protein 3 in human heart muscle using Anti-FABP3 polyclonal antibody (HPA055754).

Figure 7: Immunohistochemical staining of skeletal muscle cell (SMC) showing high expression of Troponin t type 1 using Anti-TNNT1 polyclonal Antibody (HPA058448).
References
- Friedenstein AJ. et al. (1970) Cell Tiss Kinet. 3(4):393-403.
- Pittenger MF. et al. (1999) Science 284(5411):143-7.
- Wagner W. et al. (2005) Exp Hematol. 33(11):1402-16.
- Zhang X. et al. (2006) Calcif Tissue Int. 79(3):169-78.
- In ’t Anker PS. et al. (2003) Blood.102(4):1548-9.
- Tsai MS. et al. (2004) Hum Reprod. 19(6):1450-6.
- Huang GT. et al. (2009) J Dent Res. 88(9):792-806.
- Schüring AN. et al. (2011) Fertil Steril. 95(1):423-6.
- Allickson JG. et al. (2011) Open Stem Cell. 3:4-10.
- Ab Kadir R. et al. (2012) Sci World Journal. 843843.
- Raynaud CM. et al. (2012) Stem Cells Int. 658356.
Products
* Products with enhanced validation for indicated application

HPA059297
Target: CD29/ITGB1
Clonality: Polyclonal
Validated Application: IHC*, WB
Sequence Identity Mouse/Rat: 91%/91%

HPA011868
Target: CD105/ENG
Clonality: Polyclonal
Validated Application: IHC, WB*, ICC-IF
Sequence Identity Mouse/Rat: 83%/88%

HPA034796
Target: CD106/VCAM1
Clonality: Polyclonal
Validated Application: IHC*
Sequence Identity Mouse/Rat: 72%/75%

HPA004471
Target: CD117/KIT
Clonality: Polyclonal
Validated Application: IHC*
Sequence Identity Mouse/Rat: 66%/72%

HPA008848
Target: CD146/MCAM
Clonality: Polyclonal
Validated Application: IHC*, WB*
Sequence Identity Mouse/Rat: 75%/73%

HPA010926
Target: CD166/ALCAM
Clonality: Polyclonal
Validated Application: IHC*
Sequence Identity Mouse/Rat: 94%/93%

HPA005785
Target: CD44
Clonality: Polyclonal
Validated Application: IHC, WB*, ICC-IF
Sequence Identity Mouse/Rat: 51%/47%

HPA002126
Target: CD54/ICAM1
Clonality: Polyclonal
Validated Application: IHC*, WB*
Sequence Identity Mouse/Rat: 55%/49%

HPA039835
Target: CD56/NCAM1
Clonality: Polyclonal
Validated Application: IHC*, WB, ICC-IF*
Sequence Identity Mouse/Rat: 93%/94%

HPA017357
Target: CD73/NT5E
Clonality: Polyclonal
Validated Application: IHC, WB, ICC-IF
Sequence Identity Mouse/Rat: 90%/92%

HPA003733
Target: CD90/Thy-1
Clonaility: Polyclonal
Validated Application: IHC*, ICC-IF
Sequence Identity Mouse/Rat: 64%/68%

HPA002951
Target: CSPG4/NG2
Clonality: Polyclonal
Validated Application: IHC, WB*
Sequence Identity Mouse/Rat: 87%/83%

HPA015648
Target: GDF5
Clonality: Polyclonal
Validated Application: IHC, WB
Sequence IDentity Mouse/Rat: 93%/93%

HPA031168
Target: ITGA2B
Clonality: Polyclonal
Validated Application: IHC*
Sequence Identity Mouse/Rat: 81%/77%

HPA028336
Target: MYOG
Clonality: Polyclonal
Validated Application: ICC-IF
Sequence Identity Mouse/Rat: 94%/92%

HPA063202
Target: OSX/SP7
Clonality: Polyclonal
Validated Application: IHC
Sequence Identity Mouse/Rat: 99%/99%

HPA022040
Target: RUNX2
Clonality: Polyclonal
Validated Application: IHC*, WB*, ICC-IF
Sequence Identity Mouse/Rat: 100%/81%

HPA059006
Target: RUNX3
Clonality: Polyclonal
Validated Application: IHC*, WB
Sequence Idenity Mouse/Rat: 87&/87%

HPA00536
Target: SOX11
Clonality: Polyclonal
Validated Application: IHC, WB
Sequence Identity Mouse/Rat: 82%/82%

HPA003908
Target: SOX6
Clonality: Polyclonal
Validated Application: IHC*, WB*
Sequence Identity Mouse/Rat: 97%/95%

HPA001758
Target: SOX9
Clonality: Polyclonal
Validated Application: IHC*, WB*, ICC-IF
Sequence Identity Mouse/Rat: 97%/96%