Cells Teaming Up

Initiate a class discussion prior to beginning the activity.

Ask:

Does anyone know anybody who has gotten an organ? A kidney? Some blood? Skin? Heart? Lung?

How old were they? How long did they have to wait before getting the organ? Did their body accept the organ?

Would you want to get an organ transplant if you needed one?

Watch the one-minute video, Made Possible: Teen Blake’s Heart.

Note: The video is from the site organdonor.gov, an official U.S. Government web site managed by the Health Resources & Services Administration (HRSA) of the U.S. Department of Health and Human Services (HHS).

Meet Blake

See see unos.org/data for current statistics on transplant patients.

Paraphrase:

Even before Blake was born, the doctors found he had a heart defect that was 100% fatal. They informed his parents that he'd need a new heart almost immediately. Then when he was 16 days old, the call came; they had found a heart for Blake. The donor was 15 months old and 15 pounds, and an excellent match.

The need for organ transplants continues to exceed the supply of organs. More than 116,000 people are waiting for transplants, but the demand for organs far exceeds the supply. One person's organs may be used to save many lives. People most frequently become donors after dying from a stroke, heart attack, or severe head injury.

Read the story to the class. Ask the students to turn and talk to consider the question with a partner. Possible responses:

Patients like Blake died before the first successful heart transplant in 1967. Even today, those who need hearts may die while waiting for a donor.

Blake's new heart came from another child who died.

Blake was a good match to the donor, meaning that his body chemistry had a lot in common with the body chemistry of the donor.

The History and Questions Behind Transplants

The first successful heart transplant happened in 1967. What happened to patients like Blake before that? How might you have felt if you were the parent of a child who needed a heart transplant in 1966? Why?

The heart that Blake was born with needed to be replaced when he was just over two weeks old. Where do you think Blake's new heart came from? Why does it make sense for his new heart to come from a small baby? Do you think it’s ethical to take the heart from a young baby?

Why didn't Blake's immune system reject his new heart? What do you think happened to Blake’s immune system when he received his heart transplant? Why would medical intervention be necessary?

Turn and Talk: What if the President of the United States needed the same organ a 16-day-old boy from Texas needed?

This choice would never happen, because an adult and an infant are different sizes. But if you had to decide, how would you make the call? How about deciding between the President and a single mother? Would it matter how well liked the President is, or how many kids the mother had or the children's ages?

Students choose criteria they think doctors use when adding patients to the waiting list for donated organs.

Paraphrase:

Blake was matched to a donor who died and who was a little over a year older than him. What does it mean to be a match? When an organ becomes available, a computer generates a list of possible recipients ranked according to objective criteria. The top rank goes to the patient whose organ characteristics best match the donor organ and whose time on the waiting list, urgency status, and distance from the donor organ adhere to allocation policy.

Actual criteria:

• blood type: and other tests of the immune system ensure the organ won't be rejected
• body size: a premature infant needs a much smaller heart than a fully grown adult
• distance from donor
• medical urgency: how sick is the patient?
• tissue type: a kidney is not very helpful to someone who needs a liver!
• time on wait list: patients must have a lot of patience; sometimes they can wait years for a match

Criteria not considered (and some challenges you can pose to your students as you cross these off):

• ethnicity (Are we all built the same way? how much do we differ on a cellular level, once the other criteria match?)
• fame (Should it matter how many people care about the celebrity/politician/writer, and how sad so many fans would be? )
• gender (Does it matter if a man has the heart of a woman, or vice-versa?)
• lifestyle (Should we care whether  recipients smoke, drink, take drugs, or twiddle their thumbs all day while watching TV?)
• job (What if the person were a teacher? A stay-at-home dad? A powerful executive? A mob boss? A gang member? A criminal?)
• wealth (Surgeries are expensive! Should we check the person's bank account to make sure they can pay for it? If the person has a lot of money, can they pay more to get to the head of the line? Sponsor the hospital's new surgical wing?)

Note that ethnicity is considered for helping narrow down compatible donors in bone marrow matching. It is just more uncommon to match across ethnicities.

For more videos, readings, and lessons related to organ transplants, visit Go Recycle Yourself or download the curriculum, created by Donate Life Northwest, and organ donor advocacy group in Oregon and Washington.

Now lead the class in a conversation with multiple viewpoints.

Students may prefer to take one viewpoint or the other. If you expect students will not divide evenly, you may consider randomly assigning them roles or sides in the conversation.

Explain to students:

Our class will stage a short debate on whether or not we should genetically engineer pigs to be more useful to humans. No matter how strongly you might feel about an important issue, you will review two perspectives. Understanding another point of view is critical, even if you strongly disagree with it! It is your job to argue well for the position you choose (or are assigned). Use information on this page as well as information from the prior sessions. Is it also a great time to use your previous notes and the unit's focus words; they can help you make a better argument.

For ideas about how to conduct a class conversation, click here.

End this lesson with a general discussion during which students share their own comments and raise their own questions. Note that there are some follow-up extension questions in the next, optional section of this lesson plan.

For more background on xenotransplantation, watch the fast-paced explainer on the topic from the popular YouTube sensation SciShow. This is too detailed for your middle schoolers, but good for a quick backgrounder. youtube.com/watch?v=rq5k3da_UWk

Or you can also read Sarah Zhang's article in The Atlantic: "Genetically Engineering Pigs to Grow Organs for People" (August 10, 2017)

​

Conversation: Whose Heart?

Should we genetically engineer pigs to be more useful to humans?

Human organs for use in transplants are in short supply. Ill patients can wait many years until someone matches their particular chemistry. For more than half a century, we’ve been repairing human hearts with valves from pig hearts. Unlike human organ donors who often die to give the gift of life to a patient in need, pigs are raised specifically to harvest these valves for medical use.

Human organs are rejected when the proteins on the surfaces of the cells of the donor and the patient receiving the organ don’t match. Pigs have been genetically engineered so that the valves we collect from them won’t be rejected as often. Some scientists are even trying to find ways to tailor organs to each patient’s immune system, using stem cells.

Researchers have found that pigs are as smart as chimpanzees and as social as dogs... and even cleaner than cats and dogs! Some people keep them as pets. Pigs may carry DNA that could harm humans.