Gel images of DNA isolated and amplified for specific DNA sequences.  GAPDH is a gene that Pedro knows should be in every organ of the animal model, this is his way of ensuring that he did the DNA extraction and amplification correctly. hKM is a human chunk of DNA that will let Pedro determine if there is human DNA in any of the organs he collected from the living models.  If there is human DNA in the organs, he can conclude the human MSCs he injected have migrated to those organs. Pedroexamines the gels by comparing the presence of fluorescent bands (bright blue) in his samples to the control bands that show the correct size of the DNA he has amplified.

An internet search of “DNA electrophoresis” and “PCR” will explain this process if you are interested.

Using your interactive reading Passage, review the graph below and answer the Waypoints.

STEMJourneys Real Science Cancer Path Relative Expression Table

Pedro wants to learn more about how stem cells are working in the injured joints. Now he knows that intra-articular joint injections are the best method, which of the following should be Pedro’s next step in his research?

• Choice A) Find patients at the hospital with injured joints, extract MSCs from their adipose tissue, and inject them directly into their injured joint, tracking their healing.
• Choice B) Pedro should design a controlled experiment using two animal models with the same injury. One model should get stem cells injected into their injured joint (intra-articular injection) and the other model should get only a fluid injection without any stem cells.
• Choice C) Pedro should do the experiment above but with several control models and several stem cell injected models.

Check this out!

Microscope slide image of animal model lung tissue. Nuclei of cells are stained purple. Stem cells are identified by looking for the brown immunohistochemistry stain for proteins associated with stem cells. The images look like a maze because the alveoli in the lungs are pockets of air (white space) surrounded by a thin layer of cells (purple). Can you see brown spots in any of the cells? These brown spots indicate that stem cells are indeed present in the lungs of Pedro’s living models.

Based on your analysis, what do you think Hannah’s next step should be?

• Choice A) Run a clinical trial with the drug that targets GENEblue to see if she can cure cancer. 
• Choice B) Try to collect the genetic material for GENEgreen and GENEblue and see if she can grow the genes in bacteria and other cells for future studies on the genes.
• Choice C) Design the drug to target GENEgreen, grow a whole mouse brain from stem cells and put the drug for GENEgreen on it to study what happens.

Check this out!

Fluorescent microscopic image of a neural rosette within a cerebral organoid derived from a human induced pluripotent stem cell line.

If you chose Answer C for Pedro, you’re correct!

Microscope image of animal model knee joint.

Pedro can analyze the cell type, structure, uniformity, and patterning of the joints to determine how much healing has occurred.

If you chose B, you’re correct!

More research on GENEgreen and GENEblue helps the team understand cell signals and allows them to consider targets or communicates their body of research before trying new medicines in a human population. Click here to watch a bonus video!