Expansion and genetic modification of human natural killer cells for adoptive immunotherapy of cancer

Sammanfattning: A 
century 
after 
the 
initial
 proposition 
that 
the 
immune
 system 
has 
the
 capacity 
to
 fight
 against 
tumors, 
evading 
destruction
 by 
immune
 cells
 is 
now
 well 
recognized
 as
 a
 hallmark
 of
 cancer.
 Recent
 decades
 have
 witnessed
 extraordinary
 improvements 
in
 the 
use
 of
 immunotherapy 
against 
malignancies 
and
 adoptive
 transfer
 of
 Natural
 Killer
 (NK)
 cells
 stands
 among
 promising
 tools
 in
 the
 fight
 against
 cancer.
 Clinical
 studies
 have
 demonstrated
 the
 anti‐tumor
 responses
 generated 
by
 NK 
cells 
both 
in
 the
 autologous 
and
 allogeneic
 settings
 in
 various
 cancers.
Direct 
adoptive 
transfer,
 ex
 vivo
 activation 
and/o r
expansion, 
as 
well
 as
 genetic
 modification
 of
 NK
 cells
 aspire
 novel
 improvements
 to
 current
 immunotherapy
 strategies.
 As
 such
 interventions
 develop,
 the
 quest
 for
 better
 preparation
 of 
NK 
cell
 based 
therapies 
continues. This 
thesis, 
primarily
 investigates 
the
 feasibility
 and 
potential
 of
 ex
 vivo
 expanded
 NK
 cells
 for
 cancer 
immunotherapy. 
Our 
results
p roduced
 a 
system 
that
 has 
the
 capacity 
to
 expand
 polyclonal 
and 
highly 
cytotoxic
 NK 
cells showing 
selective
 anti‐ tumor
 activity.
 Protocols
 for
 expansion
 of
 these
 cells
 from
 healthy
 donors
 and
 patients
 with
 Multiple
 Myeloma
 (MM)
 using
 current
 Good
 Manufacturing
 Practice
 (cGMP)‐compliant
 methods
 have
 been
 optimized
 in
 conventional
 cell
 culture 
systems 
as
 well
 as
automated
 bioreactors.
The
 elevated
 cytotoxic
activity
 of 
expanded 
NK
 cells 
against
 autologous
 tumor 
cells,
 along
 with
 detailed
 analysis
 of
 phenotypic
 changes
 during
 the
 expansion
 process
 has
 subsequently
 shifted
 attention 
to
 the
 interaction 
between 
NK 
and
 tumor 
cells. Both 
as
 a 
basic 
method 
to
 identify
 these
 interactions,
 and 
as 
part 
of
 further
 plans
 to
 use
 genetically
 retargeted
 NK
 cells
 in
 cancer
 immunotherapy,
 we
 have
 investigated
 methods
 for 
efficient
 lentiviral
 genetic
 modification 
of
 NK 
cells.
This
 study 
has 
resulted 
in
 an
 optimized 
stimulation 
and
 genetic
 modification 
process
 for
 NK
 cells
 that
 greatly
 enhances
 viral
 gene
 delivery.
 Along
 with
 NK
 cell
 stimulating
 cytokines,
 an
 inhibitor
 of
 innate
 immune
 receptor
 signaling
 that
 blocks
 the
 intracellular
 detection
 of
 viral
 RNA
 introduced
 by
 the
 vector
 was
 successfully
 utilized 
to 
enhance 
gene
 transfer 
efficiency,
 also
 constituting 
a
 proof‐ of‐concept 
for
 various
 other
 gene
 therapy
 approaches. Taken
 together,
 the
 work
 presented
 in
 this
 thesis
 aims
 to
 bring
 us
 closer
 to
 optimal
 ex 
vivo
 manipulation 
of
 NK 
cells
 for
 immunotherapy.
 Clinical 
trials 
with
 the 
long‐term
 expanded 
NK 
cells
 as
 well
 as 
further 
preclinical 
development
 of 
NK
 cell
 genetic 
modification 
processes 
are
 warranted.