[T]he race to discover an effective yet lucrative Ebola vaccine commenced in earnest about 10 years ago. Most of the research was funded fully or in part by such auspicious entities like BARDA (Biomedical Advanced Research and Development Authority) wing of DARPA (Defense Advances Research Projects Agency), the NIH (National Institutes of Health), USAMRIID (United States Army Medical Research Institute of Infectious Diseases), or NIAID (National Institutes of Allergy and Infectious Diseases). However, private money has also found its way into laboratories across the globe, and major pharmaceutical companies like Merck have led the way.
In 2007, Merck spun off a biopharmaceutical company called Okairos for its ‘clinical-stage’ vaccines. One of the most prominent of these vaccine candidates includes a recombinant vector based on chimpanzee adenoviruses. A vector is simply a molecular truck that delivers a payload into a living system. Adenoviruses can infect humans and primates (the literature will say ‘non-human primates’, but since I believe in Creation, I consider primates and human entirely different species with no common ancestry).
Originally, numerous researchers explored the human adenovirus (HAdV) as possible vectors, but many of us already have been exposed at some time previously, which means we already carry antibodies against HAdV—in fact, it is often cultured from the throats of sick children. Our natural immunity to HAdV meant it could not be used as a vector, but non-human versions could. Hence, about ten years ago, research began using various serotypes of chimpanzee adenovirus (ChAdV, sometimes written CAdV). One of the leading candidates for an Ebola vaccine includes the number 3 serotype, CAdV-3. Okairos, the spinoff from Merck, has found a way to remove the dangerous genes from the DNA genome of the adenovirus and insert an Ebola Glycoprotein (EVD-GP) instead. This allows the viral vector to express the Ebola GP on its outer membrane, which makes it look just like an Ebola virus particle.
Here’s how the vaccine works: Once inside the blood stream, the recombinant viral vector induces an immune response that activates the T-cell pathway. The Ebola GP on the vector’s surface is a signal that sets in motion a beautiful and effective ‘military’ response. To begin, the vector is usually gobbled up by macrophages that circulate in our bloodstream all the time. The viral vector then forces the macrophage to produce glycoproteins on its cell surface. If this were Ebola virus, the cell would also be forced to translate genes that make other proteins that send the infected person’s immune system into a deadly overdrive state, but the recombinant adenovirus vaccine vector is just an imposter, so (theoretically) only the surface GP will be produced and expressed.
Once the ‘Ebola’ GP shows up on the surface of the macrophage, that cell is now called an ‘antigen presenting cell’ (APC). That’s when T-helper cells that have very specific binding sites find the APC and latch on—like a lock and key. Now the T-helper is bound tightly to the APC, which causes the APC (macrophage) to release an SOS chemical called Interleukin-1. In response, the T-helper secretes its own SOS Interleukin-2 (IL-2). IL-2 is like calling the cavalry. Cytotoxic T-cells race to the site of the chemical message. These foot soldiers can recognize millions of different ‘shapes’, and when the right fit comes along, that T-cell binds to the APC and forces it to self-destruct, thus stopping the invasion. However, IL-2 also calls out the B-cell response. B-cells express antibodies (y-shaped proteins) which can bind to T-helper cells. When bound to the T-helper, the B-cell divides and proliferates in the bloodstream, each B-cell expressing lots and lots of antibodies specific for the invader. When the antibodies bind with glycoproteins on the pathogen’s (or in this case, the recombinant virus vector) surface, this ‘marks’ the pathogen for destruction by the macrophages. Vaccine memory is obtained when the B-cells also produce ‘memory B cells’ which continue to circulate in the bloodstream as first line defense in case of a secondary infection.
Research into the chimpanzee adenovirus vector CAdV-3 indicate that immunity only lasts for about 3 months, which would require boosters at various intervals. It is not yet known how long boosters will last, but if pharmaceutical houses like Glaxo-Smith-Kline, which purchased Okairos from Merck last year, wish to make lots of money, then boosters aren’t such a bad thing.
Are these vaccines safe? Well, let’s just say that according to a pdf at their own website, Okairos was scheduled to begin Phase I clinical trials on humans in 2013. Now, we’re told that these Phase I trials only began in October in Mali on volunteer healthcare workers. The jury is still out on side-effects and efficacy, but keep an eye on Mali. Also according to Okairos, the adenovirus vector vaccine candidate also includes something ‘secret’. This mystery ingredient is an adjuvant (a substance that helps stimulate the immune response more quickly and effectively–or so we’re told). The Okairos substance is called INV, and there is very little on their website or in the literature about the active ingredient in this INV. The adjuvant used in influenza vaccines, for example, is often squalene, a product derived from shark liver oil. Squalene has been documented as a causative agent for narcolepsy in children following vaccination with Pandemrix in 2009 during the Swine Flu epidemic.