Development of STAR growth factors for the expansion of blood cells

Nature of Issue: Significant challenges are associated with the current provision of blood
transfusion services including (1) Recruiting an adequate pool of donors to provide reliable,
matching supply of donor to recipient types (2) Typing of collected material (3) Testing for
pathogens (4) Cell counting (5) Storage, inventory control and logistics to recipient (6)
Disposal of unused blood.
For transplants, in comparison with bone marrow, there are many advantages to using cord
blood, including reduced requirement for matching between donor and recipient, and superior
engraftment. These advantages have lead to a rapid increase in the use of cord blood in
childhood leukaemia. However, cord blood volumes are small, with limited numbers of cells.
Consequently, 90% of patients (with higher body mass), are not able to benefit from this
therapy. CD34+ expansion can increase the number of cells in a cord blood sample generating
a therapeutic dose for patients regardless of body mass.
Similarly, there are significant potential benefits for using erythrocyte expansion. Several
groups in the UK have received funding to develop methods to manufacture red blood cells.
\this includes a Scottish consortium which recently received a £2.5m grant from Scottish
Development which in addition to a £3m grant from the Wellcome Trust (ref 1).
Although technically feasible, growth factor costs for CD34+ expansion technology are
prohibitively expensive. For example, Delaney et al (Nat Med, 16:232(2010) describe an
improved process for making CD34+ cells which requires growth factors costing > £140,000.
These growth factor costs, rather than technical barriers, are widely acknowledged as a key
issue likely to prevent widespread clinical adoption of this promising technology.
How these issues are being addressed: Cell Guidance Systems' STAR technology directly
addresses growth factor cost issues by delivering huge increases in performance of growth
factors via simple modifications.
Proof of concept for STAR technology has already been demonstrated: In each of the first
three growth factors that have now been generated, potency increases in the range 20-200 fold
were achieved. Since the manufacturing process is 70% efficient, cost advantages of STAR
growth factors are >10-fold. This cost advantage will dramatically reduce reagent costs and
allow cord blood and erythrocyte expansion to transition from a lab based technology to
commercial reality.
Funding Proposal: We are seeking funding for a period of 18 months and aim to generate a
series of 10 functional STAR growth factors within a period of 12 months and then use the
remaining 6 months to assess the growth factors in CD34+ and erythrocyte expansion
systems. It is estimated that each growth factor will cost £10,000-£20,000 to develop