The tobacco plant could actually aid
patients with follicular B-cell lymphoma, US researchers found. Follicular B-cell Lymphoma is a type of non-Hodgkin’s
lymphoma that attacks the immune system. A B-cell is type of lymphocyte or
white blood cell, which is responsible for defending the body against bacteria
and other types of pathogens that cause illness.
For the study, researchers at the Stanford University School
of Medicine and Large Scale Biology Corp. infected tobacco leaves with a virus
laced with a gene from the cancer, thus triggering the plants into making
antibodies of the type found on the tumors of individual patients.
“You scratch it on the leaves and it turns the plants into a
protein-producing factory for the protein of interest. A week later, you
extract the protein. It’s that fast,” the researchers reported.
Then, senior author of the study, Ronald Levy of the Stanford University and his team tested the plant-based
vaccine on 16 patients recently diagnosed with follicular B-cell lymphoma. The
researchers found that more than 70 percent of the patients developed an immune
response, and 47 percent had specific immune response that was sought. The good
part was that none of them experienced any significant side effects.
“This would be a way to treat cancer without side effects.
The idea is to marshal the body’s immune system to fight cancer. We know that
if you get the immune revved up, it can attack and kill cancer,” Dr. Levy said.
This is the first time the researchers tested a plant-based
vaccine on humans. Previous trials involving cancer vaccines developed with
animal or human cells had mixed results, Dr. Levy added.
The good news is that personalized cancer vaccines could be
produced efficiently and cheaply using plants.
“This technology is special because it’s fast and very
suitable to this customized, personalized approach because each plant can be
making a different person’s vaccine,” Dr. Levy said.
However, more studies need to be done to confirm the
effectiveness of this kind of vaccine. Dr. Levy’s study involved a small number
of patients, so the vaccine’s effectiveness at fighting the disease is
uncertain.
“While these results could potentially be very exciting,
this was a small and early-stage trial and it did not look at whether this
vaccination strategy reduced the size of the tumors,” a representative for Cancer
Research UK
told the BBC.
About 16,000 people are diagnosed with follicular B-cell
lymphoma annually, which is incurable at this time. Doctors usually monitor the
patients to see of their cancer worsens, rather than treat them with toxic
chemotherapy. That’s why a vaccine like the one involved in this study is very
important.
The study was funded by the US National Institutes of Health
while Large Scale Biology Corp. based in Vacaville, California, provided the
tobacco plants and technology to make the vaccine. As Large Scale Biology Corp.
has no money for more studies on the vaccine, the researchers are now heading
to pharmaceutical company Bayer, which has a similar technology for making the
plant vaccine.
The study is published in the Proceedings of the National
Academy of Sciences.