It’s the battle between the good white blood cells VS the bad white blood cells.
A study developed in England last 2010 made a ground-breaking news as far as preventing leukemia relapse is concerned. This time, it’s not with the use of overwhelming chemotherapeutic drugs, but one that has been developed to combat leukemia relapse naturally… one that does not cause toxic side effects to the body… one that uses the body’s own line of defense… that is none other than turning the individual’s immune system switch “on” against the potential proliferation of abnormal WBCs in the bone marrow.
We are talking about the development of vaccines against leukemia.
To understand this, let’s have a review on how vaccines generally provide immunity.
There are actually two types of immunity – the active, and the passive immunity.
In the passive immunity, what is present or is given directly here are the antibodies. Antibodies are actually chemicals made of protein, and let’s say we can have an analogy to it as the actual weapons – let’s say scud missiles – being deployed by the body’s WBCs (White Blood Cells) to specifically, emphasis on the word specifically, target the enemy – bacteria, viruses, tumor cells, etc. These are the things that the immune system recognizes as a foreign or abnormal entity, and thus must be annihilated. The passive immunity, like the name suggests, is only temporary because the antibodies are given from an external source – like a vaccine (But active immunity can also be triggered in a person’s body through vaccination, as we will discuss later). Here, the antibodies are not produced or sustained by the individual’s body so when these are all used up, so is the microbe or tumor-fighting activity it has started.
Now in contrast, active immunity, is a process whereby the person’s own WBC actively produces the antibodies anytime it spots an enemy. The source of the antibodies is not external but it is produced by the person’s immune system itself. Now for the immune system to “deploy” the antibodies, it must first spot or identify the presence of the enemy. During the first attack of the enemy, the immune system has not recognized it yet (much like an unsuspecting attack by an intruder) until it has fully blown into a disease and the immune system is now engaged in a battle with these harmful entities. When at last the immune system has won the battle, it keeps a “profile” on what the enemy looks like so that in the future, when that exact enemy intrudes the body to again create a havoc of disease, the immune system can recognize it early on in its manageable state and obliterates the enemy, stopping it on its track before it has the chance to progress and cause a full blown disease. So as you can see, active immunity can be delivered by the body on demand. So it is sustaining for years on end.
Now let’s try to connect the pieces.
If we are to choose which of the two types of immunity is preferred for the prevention of leukemia relapse, it would be one that has a longer-lasting effect, so the best type would obviously be the active form of immunity. This is exactly what researchers try to develop in the vaccine against leukemia. Why so? A person who has recovered from leukemia cannot always be 100% recovered – a sad truth. So why not use the active form of immunity whereby the immune system can always be on guard – spotting leukemic cells when they appear into the scene and target them before they multiply and start a relapse. The vaccines are designed to “train” the body’s white blood cells to recognize leukemic cells and attack them. As compared to any usual circumstances – like in an unvaccinated individual – the white blood cells are very slow, if not unable to recognize, leukemic cells.
Basically, vaccination can be used to trigger active immunity by inoculating a weak form of the microbe in the body, weak enough not to cause a full blown disease. These weak microbes can easily be destroyed by the immune system and after which, the immune system can again keep a profile of the particular disease causing microbe so that when it strikes again in real life, our immune system is ready for it. Vaccines for inducing active immunity in cases of leukemia works in a similar concept but the technique used is different though. The vaccines, let’s say, “reprogram” the immune system directly – this involves the DNA of the body’s normal white blood cells. We will examine this in a little while.
Going back to the researchers who spear headed the development of leukemia vaccines. The innovative undertaking was led by Professors Ghulam Mufti, Farzin Farzaneh, and Nicola Hardwick, M.D. at King’s College London. The researchers have participated patients who have
(AML). This form of leukemia is a common form of the illness in adults. The patients in their study were all treated at the Kings College London. For the past years, these patients were given conventional treatment for leukemia, even thought the treatments were aggressive, more than 50% the patients experience a relapse of their disease.
In generic terms, cancer vaccines do not prevent the disease in a normal individual, like what vaccines for i.e., measles, are designed to do. Instead, cancer vaccines are developed to hunt down and kill cancer cells in patients who have already had the illness. It then prompts the immune system to spot leukemic cells and clear them up whenever they can if these cancer cells return. So leukemia vaccines work in two ways – fighting the cancer cells in the person who has already the active form of the disease and helping to fight off a relapse when the disease was brought under control after aggressive conventional chemotherapy / radiotherapy.
Now let’s go back to where we left off. We said earlier that leukemia vaccines are developed in a very special way, not like any other vaccines where the doctor would just inject it in and you are all done. It’s not the case in leukemia vaccines. Although in this new era of vaccine development, the main concept for triggering the active immunity is still, of course, the main goal. But, again, the technique implemented here is way advanced and different. The new vaccine is produced by utilizing the patient’s own blood then manipulating the cells back in the lab. What is actually manipulated here is the very sole material that dictates every activity or behavior of the cells – the DNA. This DNA is much like a master pilot controlling the plane. The DNA are, essentially, the genes.
Going back to the laboratory table, the extracted cells are inoculated with, or are given, two genes. These genes kind of “upgrade” the artillery of the good white blood cells, enabling them to develop a “radar” which helps seek out leukemic cells so that they could target them. Thus, this technique enhances the body’s natural self defense against potential leukemia relapse.
Now you may ask, how were the researchers able to get these leukemia-busting genes incorporated into the cell’s own DNA. The technique is actually more intricate than you think. They don’t use ultra thin needles to inject the genes into the cells like the usual in-vitro methods, instead, they developed a man-made virus, similar to HIV, which carries the two genes right into the DNA of the good white blood cells. Now don’t think that this is HIV. It is NEVER HIV, only that the man-made virus imitates the way on how the HIV virus effectively and flawlessly delivers its genes into the white blood cells. The virus is utterly harmless.
One of the proponents, Farzin Farzaneh, professor of the Molecular Medicine at King’s College London, said, “If this ingenious method has a good success rate, then it could “rolled out” not only to treat leukemia, but other cancers as well.”
“It is the same concept as normal vaccines. The immune system is made to see something as foreign and can then destroy it itself. This has the chance to be curative.” Prof. Farzaneh added.
The cost for opting to this form of treatment is ten percent more than the conventional treatment, leukemia vaccination is estimated to cost around £15,000.
David Grant, MD, scientific director of the charity Leukemia Research, added: “Vaccines against cancer are becoming a very interesting area of research and can offer a very beneficial alternative to punishing chemotherapy…. However it is very early days and we need to see the results of these trials before we know if this potential is going to be realized.”
This research must have already been published in the Journal of Cancer Immunology, Immunotherapy.
SOURCES:
King’s College London, news release Jan. 5, 2010
Leukemia & Lymphoma Society
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