Why is the isolation of HSCs is important? How does this impact on reconstitution and inevitably, treatment for the patient?

I need recent studies for the questions below ((Don’t define anything such as what is HSC of what is multiple sclerosis or its type))
All Questions need to be answered with studies please
1. Why is the isolation of HSCs is important? How does this impact on reconstitution and inevitably, treatment for the patient? Need to make the distinction between methods used in the clinic versus those that are being used experimentally (these need to be writin in maximum 2 pages)
2. introduce preconditioning as a sub section given its importance to engraftment and to the overall survival of the patient. Also talk about lethal and au lethal dosages, myeloma lattice vs lymphoma lattice. What method have been used (irradiation vs drugs). What class of drug have been used – cytotoxic, antibodies etc).
Focus on what is being used for MS patients refer to what Richard Burt from North Western and Harry Atkins/Mark Freedman from OHrI have done.
Use as many ref you want but no basic answer I need all from recent study with referral.