stem cells in defined conditions Ludwig et al. 2006 Robert Warren, - - PowerPoint PPT Presentation

Derivation of human embryonic stem cells in defined conditions

Ludwig et al. 2006

Robert Warren, Age 20 TBI in War in Afghanistan

EzineMark.com 07/22/11

The Promise of Stem Cells

What are Stem Cells?

• Multipotent or Pluripotent Cell

Types

• Immortal
• Asymmetric Divisions

What are the different types

• f Stem Cells?
• Adult Stem Cells
• Embryonic Stem Cells
• Induced Pluripotency Stem Cells

Stem Cells Can Turn Into Any Cell in the Body and Have a Number of Uses

• 1. Cell Therapy

How Can Stem Cells be Used for Cell Therapy?

Patient Adult Stem Cells Biopsy Patient Specific Differentiated Cells Induced Pluripotent Stem Cells Six Defined Stem Cell Genes Embryonic Stem Cells

Stem Cells Can Turn Into Any Cell in the Body and Have a Number of Uses

• 1. Cell Therapy
• 2. Drug Screening
• 3. Toxicology

Screening

• 4. Developmental

Modeling

Pluripotency is a unique state.

How do you know whether your Pluripotent stem cell is Pluripotent?

You can determine if your cell is pluripotent by testing to see if it is capable of contributing to every tissue type in a live animal.

Chimeras

Chimeras

Chimeras are animals that have two or more different genotypes within the same individual.

Another Key Characteristic of Pluripotent Stem Cells is They are Capable of Incorporating into the Germline (Germline Competent).

How Could You Use Pluripotent Stem Cells In Domestic Livestock that are Capable of Producing Germline Competent Chimeric Animals?

Agriculture: Improving Livestock

• Disease Resistant

Animals

• Feed Efficient Animals
• Animals with Improved

Traits of Interest

• Introduce genes to create transgenic

animals for:

–human disease modeling –produce humanized animals for xenotransplantation

Biomedical Applications

The pre-2006 hESC culture system presented a number of challenges for cell therapy

1.Grown on feeder cells 2.Media contains fetal bovine serum Both of these have undefined factors, can be inconsistent in factors and concentrations and are a potential source of zoonotic, prion, viral contamination and exchange of information between feeder cells and hESCs (Neu5Gc- sialic acid)

What do you need to consider when you are going to develop a new cell culture system?

• 1. Media
• 2. Substrate
• 3. Other

a) Nutrition b) pH c) Osmolarity d) Maintenance signaling factors e) Antioxidents f) Antibiotic and antimicotic a) Cell adherence b) Cell signaling a) Oxygen Levels b) Xeno Free c) Ease of obtaining d) Cost

Where to start: signaling pathways potentially can be manipulated

Big Picture Question

Can they develop a human embryonic stem cell culture system that only uses defined factors that is capable

• f

maintaining these cells in a pluripotent state.

Can the TeSR1 culture system maintain the proliferation rate and pluripotency marker expression?

Which TeSR1 factors are critical to maintaining stem cell proliferation?

Which TeSR1 factors are critical to maintaining stem cell marker expression?

Are hESCs capable of maintaining Karyotype after long term culture in TeSR1?

Are hESCs capable of forming all 3 germ layers via teratoma differentiation after long term culture in Analysis of TeSR1?

Can cells morphologically resembling stem cells be derived in TeSR1 and modified substrate?

Do putative hESCs derived in TeSR1 express stem cell markers?

Do putative hESCs derived in TeSR1 express stem cell markers?

Are hESCs derived in defined conditions karyotypically normal?

Big Picture Conclusion

hESCs can be expanded and derived under defined conditions utilizing TeSR1 media on a human matrix.

What are some of the strengths of this paper?

• Used multiple stem cell lines
• Used multiple stem cell markers
• Quantitative approaches