How many of these cells that you are programming are in our bodies

Question: How many of these cells that you are programming are in our bodies
- Keywords:
  body,
  cell,
  programming
Asked by Muffin to Natasha on 7 Nov 2017.
- Natasha Myhill answered on 7 Nov 2017:
  
  Its not actually known – sometimes we dont even know if a patient has these cells until we get their tumour and try to find them. At an estimate I would say around 10 million, which sounds like a lot but when we grow up cells and give them back to patients, that is usually in the billions!

Question: How many of these cells that you are programming are in our bodies