Activate Your Natural Killer Cells
To Guard Against Infection And MalignancyJanuary 2015
By Stephen Posnick
Flu viruses are responsible for as many as 50,000 deaths every year in the US.1
Bacterial pneumonia2 causes over 60,000 deaths annually.3,4
Annual flu and pneumonia vaccines are common, but they might not be sufficient to fight off wintertime infections in the presence of a weakened immune system known as immune senescence. 5-8
The first line of defense against new invaders is our natural killer (NK) cells. As we age, NK cells lose their functionality, thus leaving us far more vulnerable to viral diseases—and the formation of tumors.9,10
Aging humans don’t have to succumb to this massive loss of NK cell function. Scientists have uncovered an enzymatically modified rice bran that has been shown to increase NK cell activity in circulating blood cells by up to 84%!11
By optimizing your NK cell function, you will be raising defenses against early death from viral illness—and against cancer as well. Enzymatically modified rice bran has been proven to help restore NK cell activity and may thereby shorten the duration and severity of winter illnesses.12
Powerful Immune Defense
Natural killer cells (NK cells) are one of your body’s most powerful defenses against infections and cancer.13-15 These tiny security guards seek and destroy cells that have been transformed by an infection with a virus or by one of many malignant changes that transform them into cancer cells.9,16
NK cells work by triggering apoptosis (programmed cell death) in cells that have been transformed by a virus or malignancy.17,18 Without this critical defense mechanism, viruses can be spread throughout the body and cancer cells can form invading, metastasized tumors.9,19
The health of these cells is critical to a robust immune system. Unfortunately, your NK cell function rapidly declines as part of the natural decline in your immune system as you age.20-22 This degeneration of immune function is medically termed immune senescence.
This explains, in part, why aging individuals become such a ready target of each year’s new influenza outbreak despite being vaccinated against the flu.
Anywhere between 5 to 20% of the US population gets the flu every year, in a seasonal wave that begins as early as October, often peaks in February, and can last until May.23-25 Older adults are at especially high risk: 90% of seasonal flu-related deaths, and up to 60% of flu-related hospitalizations, occur in people 65 and older,26 which happens to be the age when NK cell function precipitously declines.27,28 And the older we get, the higher the risk of a hospitalization or death from the flu.29
When you were younger, your NK cells, which are part of your innate immune system, could destroy the new strain of virus while your adaptive immune system “learned” its properties and then made antibodies to destroy any remaining virus.30-33 But because your NK cell function declines with age, you can easily be rapidly overwhelmed by new viral strains before your slower adaptive immunity can develop.
Similarly, older adults are at an increased risk of cancer because falling NK function fails to destroy malignant cells early on, allowing them time to develop various tricks that evade adaptive immunity while they grow into life-threatening tumors. Younger people have more robust NK function, which helps explain why cancers are generally so rare before late middle age.
Why Mainstream Medicine’s Solutions Don’t Work
Mainstream medicine has little to offer to counteract declining NK cell function. Although new vaccines can help protect against specific viruses, a decline in immune function (as part of immune senescence) limits vaccine efficacy in older people.34 More potent antiviral drugs can be developed—again to combat specific viruses—but the problem with these drugs is that they have substantial toxicity,35 they are given only after a viral infection has established itself, and they are extremely costly.36-39 Specific cytokine injections (such as low-dose interleukin-2) may help replace other components of waning immunity, but again, side effects and high costs40 limit their widespread use.41,42
A better approach would be to change the way the body responds to threats like viruses and tumor cells by directly boosting NK cell function and restoring waning immunity caused by immune senescence.5,43
By enhancing NK cell function, you would potentially be improving resistance, not to one or a few related viruses, but to virtually all viruses at once.44 In the process, you would also be potentially enhancing natural cancer resistance, not to specific cancer types, but to virtually all malignancies at once.45
Fortunately, as a result of years of research by immunologists, infectious disease experts, and oncologists, a natural compound has been discovered that can significantly improve declining NK cell function precisely when it is needed the most—during the vulnerable winter season when infectious flus are at their peak.
Natural Compound Boosts NK Cell Function
A derivative of rice bran called enzymatically modified rice bran (EMRB) has been shown to promote robust NK cell function in animal and human studies.11,46
By mechanisms that are still under investigation,46,47 EMRB has been shown to increase NK cell activity in circulating blood cells by up to 84%.11
Arabinoxylan is a type of indigestible fiber found in cell walls of the hard components of plants, such as in the husks, or bran, of cereal grains.48,49 Enzymatically modified rice bran is produced by exposing crude fiber from rice bran to enzymes isolated from the Japanese culinary mushroom, shiitake (Lentinula edodes).50,51
Recently, there has been an explosion of interest in EMRB as an NK cell-boosting agent to overcome the reduction of NK cell activity due to immune senescence. Several basic laboratory and animal studies have helped to set the stage for EMRB’s effects on NK cell function.
EMRB Boosts NK Cell Activity In Just Two Days!
An especially promising early animal study demonstrated the power of EMRB for boosting NK cell activity. When old mice with age-related reduction of NK function were injected with EMRB, they showed a greater than five-fold increase in NK cell activity within just two days of treatment.46 The enhanced NK activity in this study also resulted in increased binding of NK cells to target tissues and boosted the amounts of cell-killing chemicals inside each cell.
As a number of lab studies have shown, this increase in NK cell activity could have important benefits, including enhancing the body’s response to vaccines and chemotherapy. This magnitude of restoration of immune cells is usually accomplished only by very expensive injectable drugs, such as interleukin-252 and granulocyte colony-stimulating factor (GCSF).53-55
Another important benefit derived from EMRB’s activation of NK cells is that it enhances the body’s immune response to vaccines against both infections and cancers.56 This is of special importance to older adults, whose vaccine responses are often weaker than desired. Finding effective ways to boost the vaccine’s efficacy is a major priority in adult vaccine development.
In a landmark study of cultured human blood cells, EMRB inhibited the replication of one of humanity’s most-feared viruses, HIV, by boosting multiple immune responses that are typically suppressed by the AIDS virus.57
A series of cell culture studies has also established that EMRB’s ability to activate NK cells helps fight cancer. One such study showed that EMRB increased susceptibility of both human and mouse breast cancer cells to a common chemotherapy drug by more than 100-fold !58 This has tremendous implications for reducing the doses of toxic chemotherapy agents in current use.
And in cells from human T-cell leukemia, EMRB alone induced the death of malignant cells.59
Human Studies Prove EMRB’s Benefits
Human studies on supplementation with EMRB are equally impressive.
When a group of 20 healthy adult men and women were supplemented with EMRB for 60 days, with either a dose of 1,000 mg/day or 3,000 mg/day, NK cell activity in both groups jumped by approximately 35% in the first week.12
A similar effect was shown in another study when a lower dose of 500 mg/day of enzymatically modified rice bran was given to healthy subjects between 45 and 55 years old. With EMRB supplementation, all participants experienced a significant three-fold enhancement of NK activity in just three to four weeks—with no side effects.60
In a four-month study in individuals who were initially low in NK cell activity, supplementation with 1,000 mg/day of EMRB led to a four-fold increase in NK cell activity at two months, compared to control responses. And at the end of four months, participants showed a seven-fold increase in NK cell activity!61
EMRB has also been studied in human patients with malignancies with remarkable results. In 48 patients with multiple myeloma, a blood cancer, whose median age was 65 years, a dose of 2,000 mg/day for three months produced a significant near 84% increase in NK cell activity by the end of the second month of supplementation.11
This increase in NK cell activity could potentially result in longer life spans, as demonstrated by the next study on patients with a deadly form of liver cancer called hepatocellular carcinoma. In a three year randomized, controlled trial of EMRB vs. placebo, supplemented patients had a reduced recurrence rate of the cancer (31.6% EMRB-group versus 46.7% in controls).47 Supplemented subjects also lived longer.
- At one year, 76% of supplemented subjects were alive, but only 63% of control patients survived;
- At two years, 35% of supplemented patients were alive, but only 6.7% of control subjects survived; and
- By two and a half years, 11% of supplemented subjects survived, while no control patient remained alive.
An Optimum Regimen For A Potent Supplement
EMRB (enzymatically modified rice bran) provides a much-needed boost for aging immune systems, specifically by restoring NK cell activity. The only other way to accomplish this is with expensive pharmaceutical drugs that have to be closely monitored by an expert physician to protect against side effects.
However, EMRB may only need to be taken for a limited period of time each year. Some researchers are concerned that overstimulation of NK cells over long time spans may not be desirable.62,63
We recommend taking EMRB when your body is most vulnerable to viral infections: the roughly four-month period of the flu season’s peak activity, from early December to the end of March.23 That is when your NK cell activity is most vital for protection against influenza and its consequences. During this period of intensive immune stimulation, your body may also rid itself of incipient premalignant cells and “senile” cells that can contribute to chronic inflammation.
Once the flu season is over, you can stop the EMRB supplement until next year’s season begins. All-year immune support can be obtained by supplementing with other immune enhancers such as Cistanche and Reishi that provide broad-spectrum immune support, including enhanced NK cell activity.
At the peak of the wintertime virus season, older adults are uniquely vulnerable to potentially life-threatening infections. This is part of the bigger picture of immune senescence, the natural decline of our immune function with age.
NK cells normally provide your body’s first, immediate response to previously unknown threats.
Since NK cell function declines with age, we should consider taking special steps during the winter season to fill in this critical component of immune function.
Studies show that enzymatically modified rice bran (EMRB) rapidly and significantly boosts aging NK activity, with real-world effects demonstrated on both viral infections and cases of malignancy.
Maturing individuals should take steps to maintain and strengthen immune function year-round with supplements (such as Cistanche and Reishi) aimed at the innate and adaptive immune responses.
During the high-risk winter months, however, it would appear to be quite beneficial to add the NK cell activity-boosting effects of EMRB. This can provide the added protection needed to conquer acute and chronic issues that can markedly shorten life spans.
During that four-month period, you may also be ridding your body of accumulated precancerous cells and inflammation-generating senescent cells that have outlived their usefulness.
If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.
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