lymphoma is a cancer in which an immune cell reproduces uncontrollably. The
particular malevolent cell has a unique protein marker, which makes each case
different. Currently, patients are treated using chemotherapy and radiation
with mixed success.
vaccines use the cancerous cell's marker to trigger an immune response against
the cancer. Oncologist Ronald Levy of
Stanford University says that these protein vaccines can be grown in tobacco
plants with the help of a special tobacco plant virus.
with a normal tobacco plant, Levy says all that is needed is to "scratch
one leaf and add the virus solution." The virus infects the whole plant
and in about a week "you can harvest the leaves and get the protein
are not the only way to produce vaccines. Previous work manipulated mice to
make vaccines, but the process is expensive and time-consuming. While bacteria
may be able to produce the vaccines more quickly, they still require special
incubators and costly facilities. Levy says that plants, on the other hand, do
not need such expensive equipment so they are "very suitable for small
batches of many different products."
vaccines may also be more effective than traditional mice-produced vaccine. Plants
fold proteins differently than mice cells, and they also attach different
sugars to the proteins. Both of these might give plant-made vaccines "more
ability to attract the immune systems' attention."
and his colleagues demonstrate that plant-grown vaccines are safe in humans and
provoke an immune response. They now plan to investigate how effectively the
vaccines treat lymphoma. Levy notes the irony that the tobacco plant —
responsible for cigarettes and, thereby, lung cancer — may now offer hope
treating another type of cancer.
work is in the July 22 edition of the Proceedings of the National Academy of