Friday, May 26, 2017


Last night, on my way back home from a scientific meeting, I received my first ever coherent email from my nearly-five-year-old daughter, written all by herself from her own email account as she was getting ready for sleep. Just three short sentences, complete with misspellings and in her own inimitable style, but it was the defining moment of my night, and struck me much harder than I expected.

I have saved her email in a permanent location. The content is unimportant: what matters to me is the vista of communication it opens up. I am overjoyed and frightened as my little one begins to dip her toe into the great river of human knowledge and communication. From this moment, she begins to tie herself into the much larger world beyond our home and family, her friends and her school. Now I can start to write to her directly when I travel, to send her the pictures I take and stories I write for her while I am away.

And it's also time to start talking about information safety and privacy. Knowledge, consent, boundaries. Notice, for instance, that I have not actually shared the content of her email, because I feel those are not my words to share. Just like with other big issues, like sex and relationships, my belief is that these conversations need to start happening, at the age-appropriate level, long before they are likely to start becoming critical.

I am excited and scared, and it is wonderful and terrifying. Just like so many other parts of parenting.

From the email Harriet was responding to: her stuffed animal representative on the trip and me, all sweaty from a long terminal-to-terminal running to catch a plane.

Monday, May 01, 2017

Explaining CAR T-cell therapy with marshmallows

Last week, I had fun giving a guest lecture at my daughter's preschool on some cutting edge synthetic biology research. Part of what made it so fun was figuring out how to communicate the essence of the subject on an appropriately comprehensible level.

My daughter's class has been learning about the body, things like muscles and bones and the heart and blood.  One day a few weeks ago, she came home bubbling with excitement about having made blood out of candy that day: into some diluted corn syrup (plasma), they put mini-marshmallows to be white blood cells, red cinnamon candies to be red blood cells, and sprinkles to be platelets. I thought this sounded awesome, and it inspired me to build on that for a lesson about CAR T-cell therapy.

For this lesson, you will need white, red, green, and orange mini-marshmallows, food coloring, and toothpicks. The white marshmallows are white blood cells, the pink ones are healthy cells, the green ones are germs, and the orange ones are cancer cells.

Dip the toothpicks into the food coloring, then poke them into marshmallows to make patterns of three colored dots on the marshmallows. Put patterns on the marshmallows as follows:

  • Give all of the pink healthy cells the same pattern.
  • Give the orange cancer cells a pattern that's almost the same as the healthy cells---but with one difference.
  • Give the germs patterns that are quite different from the pink healthy cells.
  • Give the white blood cells patterns that match germs, but not the healthy cells or cancer cells.

Remember that marshmallows can get flipped around, so "red-red-blue" is effectively the same as "blue-red-red"!

You should now have a bunch of marshmallows with patterns on them.  The lesson goes like this:

  • All cells have patterns of chemicals on their outsides (Show some patterns).
  • White blood cells tell which cells are diseases by matching patterns (Show some white blood cell patterns).
  • A white blood cell leaves your healthy cells alone because they don't match (Show a white blood cell not matching a healthy cell)
  • The white blood cells learn the patterns of diseases and when they match the germs (Show a white blood cell matching a germ), they kill the germ (Eat the germ marshmallow).
  • But cancer cells are tricky, and sometimes their patterns are too close to healthy cells for the white blood cells to learn their patterns (Show how the cancer cell and healthy cell patterns are similar).
  • But now there is a new type of medicine people are trying to make work, where we can take some white blood cells out and teach them a new pattern to recognize (Take a white blood cell and mark it with the cancer pattern).
  • Now we put the white blood cells back in, and they recognize the cancer (Show how the pattern matches now) and kill it! (Eat the cancer marshmallow).
That's CAR T-cell therapy in a nutshell in 5-7 minutes, minus all the details and the cautions and concerns. I had great time teaching this class, and these 3-5 year old kids asked really good questions, like "Does everybody have white blood cells?" and "How do you teach the cells the patterns?" so I think they learned.  

And as I was writing this, my daughter arrived home, bringing a heartmeltingly lovely thank you card her classmates had made.

I think that her class got it.  Science communication win!