Courtesy Readers Digest 1981. November.
From the frontiers of science and the far horizons of
personal courage, these stories of medical triumphs and miracles will reaffirm
your faith in the awesome powers of the human spirit. Dramatic victories and human
triumphs
Of all fields of medical research, none is so full of
promise as immunotherapy—the manipulation of the body’s natural defense system
to make it fight off diseases, which have previously overwhelmed it.
Consider the California boy who suffered recurrent episodes
of infection, including several bouts pneumonia, abnormal bleeding, an enlarged
spleen and loss of hair. He was born
with an immune system so impaired that it offered no defense against certain
disease organisms. After injections of a
substance called “transfer factor”’ every six months, the boy was kept free of
infection for 48 months. Extracted from
the Shiite blood cells of healthy individuals, transfer factor is capable of
temporarily transferring specific immunes response from on person to the faulty
immune system of another.
By a similar manipulation, an eight-year old Florida girl
whose body for years was encrusted with disfiguring sores caused by a chronic
fungus infection has became a clear skinned child.
An estimated ten million Americans have diseases for which
immunotherapy bay be of use. The
diseases include cancers, arthritis, rheumatic heart disease, certain kidney
ailments, a number of infectious diseases and multiple sclerosis. In addition, many of the millions who suffer
from allergies may ultimately benefit.
Once thought to be involved only in defense against
infection, the immune system is now known to be considered with recognizing and
combating all types of foreign materials that threaten the body’s integrity,
including cancer cells, which probably develop many times throughout life. There are at least two types of lymphocytes [a
variety of site blood cells] those that act by themselves ad those that
synthesize antibodies. They make up the
two major combative forces of the immune system. The first type of lymphocyte can learn to
recognize disease organisms and other foreign materials and, once having
learned, can remember and react to the any time they reappear. Among other reactions, these lymphocytes can
release substances, which direct big scavenger cells—macrophages—to attack
enemies. Usually, it takes 4 to 48 hours
for a lymphocyte corps to congregate at an intrusion site.
Meanwhile, the second force, the antibodies—protein
molecules known as immunoglobulins—may attack.
The immune system turns out specific antibodies to fit specific antigens
[foreign materials that provoke immune forces] almost the way a key fits a
lock, and the fit inactivates the antigen.
Antibodies circulate in the blood and can act within five seconds; some
need help from a complex group of substances in the blood called “complement”
which can split apart invading bacteria, viruses and other foreign materials.
One immunologic manipulation—vaccination—has been used since
Dr.Edward Jenner discovered it as a weapon against smallpox in 1796. In recent years, attempts to transplant
kidneys and other organs have given tremendous impetus to further study of
other manipulations. Early on, the
body—attacked and sloughed off because their foreignness aroused and the immune
system quickly rejected transplanted organs.
Powerful drugs, employed in anticancer therapy, were used to suppress
the immune system, but then patients were left wide open to deadly infections.
The phenomenon noted among early transplant patients was
that suppression of the immune system made them more prone to certain types of
cancer. Did immune system play a role in
preventing cancer? In 1950s, it was
discovered that the surfaces of cancer cells contained antigens not present on
normal cells, and that these could arouse the immune system. Doon, a surveillance theory, which is still
debated, was developed; normal body cells are always, in small numbers, turning
malignant, and a major job of the immune system is to search them out and
destroy them.
Some years ago, DR. Edmund Klein, chief of dermatology at
Roswell Park Memorial Institute, Buffalo, New York, began studies testing cytotoxic
drugs [drugs that kill cells] on skin tumors.
Some to these chemicals combined with tissue materials, resulting in
highly antigenic compounds that aroused the patient’s immune system, causing it
to attack the tumor. An agry red
reaction occurred at the site, and before long the tumor disappeared as normal
tissue grew in to resurface the area where tumor had been. Here was the first clear evidence that the
immune system could destroy a cancer.
Later, Klein and his team of researchers went on to show that separated
components called ‘lymphokines’ [which are produced by a group of white blood
cells] could bring about similar reactions against tumor.
Over the years, Dr. Klein found that, at least in skin
cancers, immunotherapy could eradicate lesions in more than 70% of patients,
with no recurrences for up to 15 years.
New skin tumors, however, did occur, but at a greatly diminished
rate. Klein and his co-workers found that
immunotherapy could ferret out and eliminate skin cells not yet malignant but
on they’re way to becoming so. When the
oblivious skin cancers were treated, a dozen or more other tiny areas,
previously unnoticeable, reacted. They
proved to be pre-malignant or in very early stages of malignancy. “We found,” says Klein, “that the immune
system was a lot smarter than we were and could combat tumors we didn’t even
know existed.”
From researchers around the country and abroad come other
reports that science is taking its first uncertain steps on the route to
immunotherapy for cancer. In the early
1970s and M.D. Anderson Hospital and Tumor Institute in Houston, for example,
Dr Evan M. Hersh and colleagues have used BCG, the tuberculosis vaccine, to
treat 300 patients with malignant melanoma [a kind of skin cancer]. Some had had surgery before treatment and
were disease-free. In these patients,
the BCG clearly prolonged the disease-free interval, compared to controls. In others, who could not be treated surgically
because their cancer had spread, chemotherapy plus BCG, compared with the
results of chemotherapy alone, prolonged the remission and length of survival.
At a 1972 National Institutes of Health conference on
immunotherapy, Dr Sol Roy Rosenthal and other investigators from the University
of Illinois reported on a Chicago study: from 1964 through 1969, only one death
from leukemia was recorded among 54,414 children up to six years of age who had
been vaccinated at birth with BCG against tuberculosis. In contrast, 21 deaths from leukemia were
reported among 172,986 children of similar age and race who had not been
vaccinated—a rare more than six times as great.
A controlled stud has now been set up nationwide by the Children’s
Cancer Study Group to investigate BCG as a vaccine against leukemia.
Few investigators believe that the chemicals they are using
experimentally today will be the ones in use five years hence, to that
immunotherapy alone can be expected to conquer a cancer that has become well
established. They see the immunolic
killing of such tumor cells as a kind of “numbers game.” Each immune agent has a certain limited
capacity to stimulate the immune system.
So, when a cancer is well established immunotherapy may be the most
effective after the tumor load has been lightened by surgical removal of the
primary tumor, or after regression has been induced by chemotherapy.
Once the most fundamental discoveries about the immune
system are that it sometimes defeats itself by producing a substance that
blocks its own immune activities. Today,
many cancer scientists are aggressively pursuing the idea that if one could
remove this “blocking factor,” the cancer patient should be able to attack his
disease more effectively with his own immune cells. Until recently, no one has been able to devise
a way to put the theory to the real test.
For the only way to remove the blocking factor is to exchange all to the
patient’s blood daily with normal blood—a so-called exchange transfusion. Such an experiment was considered impossible,
since it would require not only several thousand pints of blood, but also the
simultaneous presence in one cancer center of facilities, equipment and skills
rarely available in one place.
In the winter of 1974, however, the beginnings of the
crucial experiment were set in motion at the Mercy Catholic Medical Center in
Philadelphia be Dr. Isaac Djerassi, who pioneered platelet transfusion to stop
incontrollable bleeding in cancer patients.
Dr. Djerassi selected a volunteer with malignant melanoma for who no
other useful treatment was available.
The patient, though in good general condition, had a tumor, which could
be easily inspected, touched and measured, so that any change could be readily
detected.
Plastic tubes were placed in the patient’s wrist artery and
vein, and attached daily to a machine, which continuously separated the blood
cells from the fluid part of the blood—the plasma that may contain the blocking
antibodies. While the machine returned
the blood cells to the patient, Dr. Djerassi kept out the plasma and it its
place injected normal plasma back into the patient. In this fashion, Djerassi exchanged all of
the patient’s blood plasma twice daily, using the plasma from 30 to 40 pints of
blood everyday.
Dr. Djerassi turned to leading cancer scientists for help in
evaluating the results of the experiment.
Regular simultaneous telephone conferences were held, and decisions were
made jointly as to what studies to make and who would make then. Appropriate blood specimens were collected
from the patient and dispatched to the other investigators. All results were reported during the next
telephone conference.
Eighteen days after the beginning of the daily exchange
transfusions, the patient’s tumor was measurably smaller. Though the doctors could not halt the tumor
growth completely [once the transfusions were stopped the growth began again],
they have made much progress in researching the vital questions about what
caused their temporary success.
The remissive effect on the tumor seems to have been due to
the removal of the blocking factor from the patient’s blood, and possibly,
because in the normal plasma given in the patient, there was some crucial
component which the patient did not possess.
Additional work with many patients is needed before the final answers
will be forthcoming, but Dr. Djerassi feels that the cancer scientists are on
the right track in pursuing this line of research.
Despite the abundance of promise in immunotherapy,
researchers are proceeding cautiously, wary of missteps, aware that much
remains to be learned about how to manipulate most effectively and safely what
is probably the body’s most complex and fundamental system. But distinguished immunologist and Sasker
Award winner has observed: “Recent developments are asking up to nothing less
than an entirely new picture of how the immune system works. It is as though we had been viewing things
out of focus for years, and now suddenly, they have become sharply defined”.
“In immunology,” says immunology authority Sir McFarland
Burnet, “we are part of the wave of the future.” With that, few would disagree.
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