Table 1.

Theoretical comparison between IV and ex vivo (EV) MSCs

Parameter	IV MSCs	EV MSCs	Δ (EV/IV)
Biodistribution (reaction volume)	5,000 ml (human blood volume)	100 ml (reactor volume)	1/50
Half‐life (duration)	1–3 hours	>>72 hours	>288×
Initial dose (cell number)	200 M	>>200 M	>1–5×
∼MSC: leukocyte compartment	<1:100	>5:1	>5,000×

Abbreviations: MSC, mesenchymal stromal cell; EV, ex vivo; ∼, The ratio between MSCs to leukocytes is approximated in the table (rather than an absolute precision calculation).