Study Supports Potential for Off-the-Shelf Dendritic Cell Vaccine
Development
Geron Corporation (Nasdaq:GERN) today announced the publication of data
demonstrating that dendritic cells (DCs) scalably manufactured from
human embryonic stem cells (hESCs) exhibit the normal functions of
naturally occurring human DCs found in the bloodstream. These findings
support the use of hESC-derived DCs in therapeutic vaccine applications
for cancer and other diseases. Substituting standardized, off-the-shelf
hESC-derived DCs for current approaches using DCs obtained from
individual patients may result in more cost effective and reliable
approaches to cancer immunotherapy.
The study, authored by Geron scientists and collaborators Prof. Waldmann
and Dr. Fairchild at the Sir William Dunn School of Pathology,
University of Oxford, appears online in advance of print in the journal Regenerative
Medicine. The abstract of the publication is available at http://www.futuremedicine.com/doi/abs/10.2217/rme.09.25.
Dendritic cells (DCs) are immune cells that detect pathogens (e.g.
viruses or bacteria) and activate other immune cells (called T-cells) to
launch an immune attack against the pathogen. DCs reside in small
numbers within most tissues, particularly where there is contact with
the external environment, such as the skin or gut. DCs will engulf and
digest a foreign pathogen and present pieces of pathogen proteins (known
as antigens) on the cell surface. The presentation of antigen by DCs
activates the T-cell immune response directed against that pathogen. In
a similar manner, dendritic cells can also educate the immune system to
initiate an immune response against aberrant cells in the body, such as
tumor cells.
The data in the Regenerative Medicine publication show that
immature hESC-derived DCs are able to take up, process and present
antigens, and then, following maturation in the manufacturing process,
are able to migrate, produce pro-inflammatory cytokines and induce
specific immune responses to both tumor and viral antigens in vitro.
These data show that hESC-derived DCs display the functions of human DCs
taken from the bloodstream.
The potential for DCs to stimulate potent and specific immune responses
is being explored in clinical trials of DC vaccination protocols for the
treatment of malignant and infectious diseases. “We are using a DC
platform with our cancer vaccine directed against telomerase, GRNVAC1,
currently in Phase II studies in AML,” said Thomas B. Okarma, Ph.D.,
M.D., Geron's president and chief executive officer.
