Can Stem Cell Therapy be Used
to Treat Lyme Disease?
The answer is apparently “yes” according to Amy Scer, who
is the first woman to use stem cell technology to treat her Lyme disease. She went to India for the treatment
and is now completely free from a chronic disease that she suffered with for years.
Others are following her lead due to the lack of options
currently available to suffering victims of Lyme disease.
However, in the US, a controversy continues to gather
ammunition, arguing whether taxpayers should pay for something that private venture capital is quite capable
of funding, and more intensly the argument over using embryos from living (and frequently viable)
Much of the following is taken from material published by
the National Institute of Health.
Studying stem cells will help us understand how they
transform into the dazzling array of specialized cells that make us what we are. Some of the most serious
medical conditions, such as cancer and birth defects, are due to problems that occur somewhere in this
process. A better understanding of normal cell development will allow us to understand and perhaps correct
the errors that cause these medical conditions.
Another potential application of stem cells is making
cells and tissues for medical therapies. Today, donated organs and tissues are often used to replace those
that are diseased or destroyed. Unfortunately, the number of people needing a transplant far exceeds the
number of organs available for transplantation. Stem cells offer the possibility of a renewable source of
replacement cells and tissues to treat a myriad of diseases, conditions, and disabilities including
Parkinson's and Alzheimer's diseases, spinal cord injury, stroke, burns, heart disease, diabetes,
osteoarthritis and rheumatoid arthritis.
Have human embryonic stem cells successfully treated any
Scientists have been able to do experiments with human
embryonic stem cells (hESC) only since 1998, when a group led by Dr. James Thomson at the University of
Wisconsin developed a technique to isolate and grow the cells. Moreover, Federal funds to support hESC
research have been available since only August 9, 2001, when President Bush announced his decision on Federal
funding for hESC research. Because many academic researchers rely on Federal funds to support their
laboratories, they are just beginning to learn how to grow and use the cells. Thus, although hESC are thought
to offer potential cures and therapies for many devastating diseases, research using them is still in its
Adult stem cells, such as blood-forming stem cells in bone
marrow (called hematopoietic stem cells, or HSCs), are currently the only type of stem cell commonly used to
treat human diseases. Doctors have been transferring HSCs in bone marrow transplants for over 40 years. More
advanced techniques of collecting, or "harvesting," HSCs are now used in order to treat leukemia, lymphoma
and several inherited blood disorders.
The clinical potential of adult stem cells has also been
demonstrated in the treatment of other human diseases that include diabetes and advanced kidney cancer.
However, these newer uses have involved studies with a very limited number of patients.
In the new issue of Cell Stem Cell, scientists report that
the same transcription factor, which is crucial for the survival of different stem cell types, can behave
This study clearly showed for the first time that
different types of stem cells are defined by exclusive combinations of genes working together, and this is
under the influence of a single key stem cell factor (called Sall4).
The finding is timely since other researchers have
recently revealed that specific genetic recipes can be used to turn non-stem cells into different stem cells
that can be useful clinically.
This finding reveals important insights about how
scientists may be able to manipulate and engineer different stem cells for the treatment of human
Understanding the behavior of transcription factors, a
class of gene regulators, helps pave the way for important advancements in stem cell technology and clinical
Stem cells are important for the cell-based therapy of
many degenerative tissue disorders. Each type of body tissue has its own unique type of stem cells whose
behavior is controlled by different sets of genes.
Given the enormous complexity of each stem cell type and
the underlying genetic bases for their unique purpose, it has been a major challenge for scientists to
unravel the similarities and differences between the different stem cells.
The latest research, led by Bing Lim, Senior Group Leader
at the Genome Institute of Singapore (GIS), focused on identifying and understanding the functions of
powerful genetic molecules, also known as "stem cell factors".
Dr. Bing Lim said, "This new discovery has provided us
with important new leads and ideas on how to grow and expand various stem cells for clinical research and
Dr. Daniel Tenen, Professor of Medicine at Harvard Medical
School, and Director for Cancer Research Centre of Excellence at the National University of Singapore, said,
"These studies are of great significance, as they provide important clues as to how a single transcription
factor might regulate different targets in different stem cells."
Interestingly, this stem cell factor also appeared to be
associated with certain diseases, particularly leukemia.
Dr. Li Chai, Instructor at the Department of Pathology at
the Harvard Medical School, added that, "as Sall4 plays an important role in both normal hematopoietic stem
cell function and in leukemia stem cells, these findings may have clinical relevance; they may lead to
understanding differences between normal and cancer stem cells."
After years of working toward this goal, scientists at the
OU Cancer Institute have found a way to isolate cancer stem cells in tumors so they can target the cells and
kill them, keeping cancer from returning.
A research team led by Courtney Houchen, M.D., and
Shrikant Anant, Ph.D., discovered that a particular protein only appears in stem cells. Until now,
researchers knew of proteins that appeared in both regular cancer cells and stem cells, but none that just
identified a stem cell.
The group has already begun work to use the protein as a
target for a new compound that once developed would kill the stem cells and kill the cancer. By targeting the
stem cells, scientists and physicians also would be able to stop the cancer from returning.
Houchen and Anant are focusing on adult cancer stem cells
because of the major role they play in the start of cancer, the growth of cancer, the spread of cancer and
the return of cancer.
Current therapies generally do not target stem cells in
tumors. This allows stem cells to wait until after chemotherapy or radiation treatments to begin dividing.
Researchers believe these stem cells are often responsible for the return of cancer after treatment. The
identification of the stem cell marker enables researchers to develop new therapeutics that can target these
Adult stem cells work as essential building blocks in
organs by replenishing dying cells and regenerating damaged tissues. Unlike embryonic stem cells, the use of
adult stem cells in research and therapy is not controversial because the production of adult stem cells does
not require the destruction of an embryo.
Researchers expect to have initial testing completed to
begin the first phase of clinical trials within 5 years led by Russell Postier, M.D. The compound, if
successful in human trials, is expected to be available to the public within 10 years.
In December of 2008, Science Daily reported the
following: A research team led by the La Jolla Institute for Allergy & Immunology and Albany Medical College
has illuminated the important role of natural killer (NK) T cells in Lyme disease, demonstrating that the once
little understood white blood cells are central to clearing the bacterial infection and reducing the intensity and
duration of arthritis associated with Lyme disease.
"Our findings are that the NK T cells are critical to
preventing the chronic inflammatory infection that causes Lyme arthritis and they participate in clearing the
bacteria which cause it," said Mitchell Kronenberg, Ph.D., the La Jolla Institute's president &
scientific director and co-senior author on the study, which used a mouse model of Lyme disease. Lyme disease
is caused by Borrelia burgdorferi, a bacterium transmitted to humans by the bite of infected deer ticks.
Typical symptoms include fever, headache, fatigue, and sometimes skin rashes. If left untreated, it can
spread to the joints, the heart and the nervous system, and it can lead to serious health problems. Lyme
disease currently is the most common vector (insect)-borne disease in the United States.
"What this study demonstrates is that NK T cells are an
important part of our defense against Lyme disease," said Timothy J. Sellati, Ph.D., an associate professor
at Albany Medical College and co-senior author on the study. "This offers the possibility that we can exploit
that knowledge therapeutically and potentially develop immunological agents that can trigger more NK T cells
to aide in fighting this disease." Sellati added that "NK T cells alone cannot clear Lyme disease, but are a
key part of a collective immune defense."
The study's findings are outlined in a paper, "NKT cells
prevent chronic joint inflammation after infection with Borrelia burgdorferi," published this week in the
online version of the journal Proceedings of the National Academy of Sciences.
In an earlier study published in Nature Immunology,
Kronenberg, Sellati and co-workers had shown that a glycolipid, a type of fat, found in the membrane of
Borrelia burgdorferi triggered an immune response from the NK T cells. "We had found that if you gave that
lipid to mice or humans, it would activate NK T cells," Kronenberg said. While this suggested the cells might
play a significant role in Lyme disease, "we were missing in vivo (in the body) evidence showing that the NK
T cells were activated following infection and were important for killing and clearing the Lyme disease
bacteria," he said, noting that the latest study demonstrates this in an animal model.
Sellati said the finding is particularly important because
it opens new lines of investigation as to the causes of chronic Lyme disease. "That's what's so exciting when
you identify a new cell type as playing a central role in preventing the disease process," he said. "So in
those individuals who have a more severe form of the disease, you can study their NK T cells and see if
there's some deficiency that prevents those NK T cells from killing and clearing the
In their studies, the researchers worked to model the
natural route of Lyme disease infection as closely as possible. "The way people typically get Lyme disease is
that they're out hiking and they get bitten by a deer tick," said Kronenberg. "So what we did in the lab was
to get ticks infected with Borrelia burgdorferi from collaborators at the University of Connecticut Health
Science Center and then used those ticks to infect mice in a confined and controlled
The researchers used one group of mice genetically
engineered not to have NK T cells, while the control group had the cells. "The mice that didn't have NK T
cells were not as capable of clearing the (Lyme disease) bacteria," Kronenberg said. "And they developed a
chronic arthritis, while the control mice did not." He said the results were quite marked. "You could see
under the microscope more numerous inflammatory cells in the joints of the mice that lacked the NK T cells
weeks after infection."
Discovered in the 1990s, NK T cells are disease-fighting
white blood cells of the immune system whose inner workings are still being defined. While most T cells
respond to foreign proteins to protect the body, NK T cells are unique in that they respond to glycolipids,
which are natural biochemicals made of linked fat and sugar. Prized for initiating a fast and vigorous immune
response, NK T cells are emerging as a subject of significant scientific interest because of their potential
for fighting bacterial infections and cancer. Kronenberg and Sellati have been among the nation's leaders in
studying these cells.
Kronenberg's laboratory was among the first to identify
bacteria which naturally induce an immune response from the NK T cells. Thus far, he has identified two such
bacteria— Borrelia burgdorferi and Sphingomonas species, a fairly benign bacteria found throughout the
environment. However, he believes many other types of bacteria may also trigger the NK T cells. "This is an
exciting possibility that needs to be further explored as it could lead to the development of treatments for
many bacterial diseases."
Stem cells are cells found in most, if not all,
multi-cellular organisms. They are characterized by the ability to renew themselves through mitotic cell
division and differentiating into a diverse range of specialized cell types. Research in the stem cell field
grew out of findings by Canadian scientists Ernest A. McCulloch and James E. Till in the 1960s. The two
broad types of mammalian stem cells are: embryonic stem cells that are found in blastocysts, and adult stem
cells that are found in adult tissues. In a developing embryo, stem cells can differentiate into all of the
specialized embryonic tissues. In adult organisms, stem cells and progenitor cells act as a repair system for
the body, replenishing specialized cells, but also maintain the normal turnover of regenerative organs, such
as blood, skin or intestinal tissues.
Stem cells can now be grown and transformed into
specialized cells with characteristics consistent with cells of various tissues such as muscles or nerves
through cell culture. Highly plastic adult stem cells from a variety of sources, including umbilical cord
blood and bone marrow, are routinely used in medical therapies. Embryonic cell lines and embryonic stem cells
generated through therapeutic cloning have also been proposed as promising candidates for future
Stem cell controversy is the ethical debate centered on
research involving the creation, usage and destruction of human embryonic stem cells.
Extraction of such cells using current technology requires
the destruction of the human embryo which gives rise to the opponents of the research who argue that this
practice is a slippery slope to reproductive cloning and fundamentally devalues the worth of a human
Contrarily, some medical researchers in the field argue
that it is necessary to pursue embryonic stem cell research because the resultant technologies could have
significant medical potential, and that excess embryos created for in vitro fertilization could be donated
with consent and used for the research.
This in turn, conflicts with opponents in the pro-life
movement, who advocate for the protection of human embryos. The ensuing debate has prompted authorities
around the world to seek regulatory frameworks and highlighted the fact that embryonic stem cell research
represents a social and ethical challenge. Other controversies include conflict of religious practices and
the great power physicians would possess.
Meanwhile, people who are unwilling to wait for these
issues to resolve themselves are going overseas to countries unhindered by such debate and willing to avail
the same technology, at great cost, but in many cases changing the prospects of human life from suffering to