Human blood progenitors made from skin

Following earlier studies showing that mouse fibroblasts could be converted into neurons and muscle cells without the need to create first iPS, a recent paper in Nature presented the first direct conversion of human skin cells into blood subtypes.
Szabo et al. (7 Nov 2010; doi:10.1038/nature09591) transduced human skin fibroblasts with the pluripotency factor OCT4 and grew them with different cytokines to convert them into hematopoietic progenitors and mature blood cells. After a few days, the cells expressed the pan- haematopoietic factor CD45 and eventually gave rise to all blood cell types (myeloid, erythroid and megakaryocytic lineages), depending on the cytokines added to the medium.

The hemotopoietic differentiation medium used in this study to derive blood progenitors was made with cytokines from R&D Systems:

Embryonic stem cell defined media: culturing goes from art to science

A team of researchers at the University of Wisconsin-Madison reports the development of a fully defined embryonic or pluripotent stem cells culture system.
[R&D Systems has an excellent defined media, StemXVivo culture matrix, composed of a mixture of recombinant human adhesion molecules for the culture of stem/progenitor cells.]
Writing this week (Nov. 14, 2010) in Nature Methods, a team led by Laura Kiessling, unveiled an inexpensive system that takes much of the guess work out of culturing the all-purpose cells.
"It's a technology that anyone can use," says Kiessling. "It's very simple."
The new culture system utilizes a synthetic, chemically made substrate of protein fragments, peptides, which have an affinity for binding with stem cells. Used in combination with a defined growth medium, the system devised by the Wisconsin team can culture cells in their undifferentiated states for up to three months and possibly longer. The system, according to the new report, also works for induced pluripotent stem cells, the adult cells genetically reprogrammed to behave like embryonic stem cells.

Figure 3

(Lim et al.)

: Synthetic surfaces support the long-term culture of pluripotent stem cells.

(a) Immunostaining of H9 hES cells cultured for three months in mTeSR with ROCK inhibitor on the synthetic surface for Oct-4 and SSEA-4, and stained with DAPI. Scale bar, 200 μm. (b,c) Immunostaining of DF19-9 7T iPS cells cultured for 2.5 months in mTeSR with ROCK inhibitor on the synthetic surface for nanog and E-cadherin (b) or for Sox2 and Tra-1-60

R&D Systems reagents used in this study:

recombinant proteins:
Activin A
BMP-4
Noggin

Plates:
Vitronectin-coated plates

Antibodies:
Oct-4
Nanog
Sox-2
β-III tubulin
FoxA2
Fatty acid binding protein 4
Alkaline phosphatase, APC-conjugated
SSEA-1, PE–conjugated


Joseph R Klim, Lingyin Li, Paul J Wrighton, Marian S Piekarczyk & Laura L Kiessling. A defined glycosaminoglycan-binding substratum for human pluripotent stem cells. Nature Methods, 14 November 2010 DOI: 10.1038/nmeth.1532

[News adapted from this UW-Madison press release]

Detection of Epithelial-To-Mesenchymal Transition

R&D Systems now offers a Human EMT 3-Color Immunocytochemistry Kit (Catalog # SC026). The kit contains three fluorochrome-conjugated antibodies that can be used together for single-step immunocytochemical assessment of epithelial-to-mesenchymal transition (EMT). EMT is a mechanism by which cells shed their epithelial characteristics and acquire more migratory mesenchymal cell-like properties. This process is essential for embryonic development and wound healing, but is also involved in cancer metastasis. The antibodies included in the kit are NorthernLights 637-conjugated anti-human E-Cadherin, NorthernLights™ 493-conjugated anti-human Vimentin, and NorthernLights 557-conjugated anti-human Snail. Snail is a transcription factor that acts as a master regulator of EMT, while E-Cadherin and Vimentin serve as epithelial and mesenchymal markers, respectively.


Detection of EMT in TGF-beta 1-treated Human Lung Carcinoma Cells using the Human EMT 3-Color Immunocytochemistry Kit. A549 human lung carcinoma cells were either untreated (A) or treated with Recombinant Human TGF-beta 1 (Catalog # 240-B) for 48 hours (B ). The cells were analyzed for an epithelial-to-mesenchymal transition (EMT) by simultaneously staining with antibodies contained in the Human EMT 3-Color Immunocytochemistry Kit (Catalog # SC026 ), including NorthernLights 637-conjugated anti-human E-Cadherin (pseudo-colored gray), NorthernLights 493-conjugated anti-human Vimentin (green), and NorthernLights 557-conjugated anti-human Snail (red). Induction of EMT following TGF-beta 1 treatment was revealed by down-regulation of E-Cadherin and concurrent up-regulation of Vimentin and Snail.

For more information on products for EMT research, please visit our website at www.RnDSystems.com/go/EMT

A Mesenchymal-to-Epithelial Transition Initiates and Is Required for the Nuclear Reprogramming of Mouse Fibroblasts

Li et al. Cell Stem Cell, Volume 7, Issue 1, 51-63, 17 June 2010
10.1016/j.stem.2010.04.014

Highlights:

• Mouse fibroblast reprogramming involves a mesenchymal-to-epithelial transition
• Sox2, Oct4, and c-Myc suppress TGF-β signaling
• Klf4 activates multiple epithelial genes including E-cadherin
• E-cadherin knockdown impairs reprogramming

R&D Systems used in these studies:

• Klf4 Exacta ChIP

Klf4 ChIP from Figure 4 of Li et al.

• Human anti-Nanog antibody
• Recombinant human TGFb1
• Recombinant human TGFb2
• Recombinant human TGFb3
• Recombinant human Activin A
• Human TGFb1 ELISA
• Human TGFb2 ELISA
• Human TGFb3 ELISA

R&D Systems' Cancer Stem Cells Products

To see a comprehensive list of R&D Systems' products for Cancer Stem Cells research, click here.

New: APC-conjugated Mouse CCR2 Monoclonal Antibody

Detection of CCR2 by Flow Cytometry. A. L1.2 mouse pro-B cells transfected with mouse CCR2 were stained with APC-conjugated Mouse CCR2 Monoclonal Antibody (Catalog # FAB5538A; filled histogram) or APC-conjugated Rat IgG2B Isotype Control (Catalog # IC013A; open histogram). B. Mouse peripheral blood cells were stained with APC-conjugated Mouse CCR2 Monoclonal Antibody (Catalog # FAB5538A) and PE-conjugated Mouse Integrin alpha M/CD11b Monoclonal Antibody (Catalog # FAB1124P).


R&D Systems now offers an APC-conjugated Mouse CCR2 Monoclonal Antibody (Catalog # FAB5538A) for flow cytometry. CCR2 is a G protein-linked chemokine receptor that preferentially binds monocyte chemo-attractant protein-1 and -3 (MCP-1/CCL2 and MCP-3/CCL7). Cells that respond to the action of MCP-1, and are therefore likely to express CCR2 receptors, include monocytes, T cells, natural killer cells, basophils, mast cells, and dendritic cells. CCR2, along with other chemokine receptors, is involved in the recruitment of leukocytes to sites of inflammation, making it a potential target for inflammatory disorders. In addition, CCR2 can serve as an HIV fusion co-factor, suggesting that it may also serve as a target for inhibiting the HIV infection process. For more information, please visit our website at www.RnDSystems.com or call 1-800-343-7475.

R&D Systems FoxP3 Antibodies and Kits

FoxP3 is a major marker for regulatory T cells (T Regs) and it is a member of the forkhead family of DNA-binding proteins. T Regs are essential regulators of the immune system and important players in autoimmune disorders, transplantation therapy, and cancer. R&D Systems has developed a new FoxP3 polyclonal antibody that is highly specific (Figure 1). This new FoxP3 antibody has been validated for Western blotting (Figure 1), immunohistochemistry (Figure 2), multi-color flow cytometry (Figure 3) and chromatin immunoprecipitation (Figure 4).









check out all R&D Systems FoxP3-related products here