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+ | **Type:** Conference presentation\\ | ||
+ | **Presenter: | ||
+ | **Conference: | ||
+ | **Location: | ||
+ | **Date: | ||
+ | **Notes:** [[http:// | ||
+ | |||
+ | |||
+ | |||
+ | ===== Transcript ===== | ||
+ | |||
+ | {{ vimeo> | ||
+ | |||
+ | My talk is going to be primarily about translational medicine, that | ||
+ | Dr. Hershko mentioned as being one of the waves of the future. | ||
+ | I'm going to be talking at the level of the gene, and I'm going to | ||
+ | be talking at the clinical level as well. | ||
+ | |||
+ | I would like to first make an apology to those of you who are | ||
+ | scientists here for explaining what //in silico// means. But there are | ||
+ | three phases of biology, of biological research. There' | ||
+ | means in living persons. There' | ||
+ | the lab in cell culture. And there' | ||
+ | across //in silico// research was here at the Hospital for Sick Children | ||
+ | in Toronto back in 1981. This is a group of us there at the time. | ||
+ | We'd just come back from a conference where IBM had shown how | ||
+ | they were using their new supercomputers to produce human | ||
+ | insulin. This was Humulin, and it was synthesized with the use of | ||
+ | //in silico// technologies, | ||
+ | one of the first of the major drugs that was produced by | ||
+ | computers. This was my first introduction to //in silico// work. But | ||
+ | most of you would be more familiar, of course, with the use of in- | ||
+ | silico technologies in the decoding of the human genome and | ||
+ | perhaps more importantly, | ||
+ | decoding now of 1078 (last time I looked it up) bacterial genomes, | ||
+ | fully decoded. | ||
+ | |||
+ | The NIH has just started a large Human Microbiome Project, which | ||
+ | over the next ten years aims to define exactly what microbes exist | ||
+ | in the organism we call //Homo sapiens//. Basically, you'll all be | ||
+ | familiar with the normal areas where microbes are expected— | ||
+ | nasal cavities, oral, skin, GI and urogenital. But it's known that | ||
+ | microbes are far more prevalent in the human body than anybody, | ||
+ | up until now, has even dreamed. The NIH says that in a human | ||
+ | body approximately 10% of the cells are human cells and | ||
+ | approximately 90% are bacterial cells. | ||
+ | |||
+ | Now remember that bacterial cells are really small. You will have | ||
+ | hundreds or thousands of them inside each infected human cell. | ||
+ | However, those are the numbers from the NIH Microbiome Project, | ||
+ | and that's a staggering start. We then go to the next set of | ||
+ | numbers. There are approximately 25,000 human genes active in | ||
+ | the human body, and about one million bacterial genes. The | ||
+ | interaction between the bacterial genes and the human genes, of | ||
+ | course, will help define how the organism //Homo sapiens// actually | ||
+ | operates. | ||
+ | |||
+ | Well, why is this important? If we look at, for example, the //E. coli// | ||
+ | glucose metabolism, you can see at the top here we've got | ||
+ | Glucose-6-phosphate coming in, and at the bottom I've taken it as | ||
+ | far down as Pyruvate and the citric acid cycle down below. But | ||
+ | basically this shows the genes in the //E. coli// organism, the proteins | ||
+ | that are produced, and the end products of that protein action on | ||
+ | the input glucose-6-phosphate. And the main thing to notice is | ||
+ | that it's not all that different from the way the human body utilizes | ||
+ | glucose. You can see a lot of names that you recognize. Obviously | ||
+ | the end products hereadenine, | ||
+ | tyrosine, tryptophan, those are very well-known. They' | ||
+ | in man, but you'll find also glycagon and a number of others, ribo- | ||
+ | 5-phosphate, | ||
+ | if one studies the human glucose metabolism. This particular | ||
+ | analysis was done by Vijay at Bielefeld University in Germany, and | ||
+ | he has done a lot more work than just this one slide shows. | ||
+ | But really, what I wanted to point out was, there is not a lot of | ||
+ | difference between the way that //E. coli// metabolizes glucose-6- | ||
+ | phosphate and the way the human body does. Many of these | ||
+ | metabolites are the same. If you could have an interaction | ||
+ | between the //E. coli// genome and the human genome, then an | ||
+ | entirely new spectrum of transcription and translation is opened | ||
+ | up. Now, in fact, published in the Proceedings of the National | ||
+ | Academy of Sciences last year by Kwang-il Goh, et al, they actually | ||
+ | took all the genes in the gene bank, and they then plotted all the | ||
+ | diseases, bone, cancer, diseases right through to skeletal, | ||
+ | respiratory, | ||
+ | various diseases and the genes that were common to the various | ||
+ | diseases. | ||
+ | |||
+ | Now if we enlarge a section of that, we have the rheumatic | ||
+ | diseases here, the rheumatic diseases because those of you who | ||
+ | are from Szechuan Province, I'm going to be giving a more | ||
+ | extended seminar next Monday at 2PM at West China Medical | ||
+ | Center in Chengdu. So I'm focusing on the rheumatic diseases | ||
+ | here, but we could focus on the neurological or any of the other | ||
+ | diseases. If we take this one gene here, ACE, which produces the | ||
+ | angiotensin converting enzyme, it is known to be associated with | ||
+ | Myocardial Infarction, with Renal tubular dysgenesis, with | ||
+ | Alzheimer' | ||
+ | My particular interest in it was that it was also associated with the | ||
+ | first disease that we studied, which was a disease called | ||
+ | Sarcoidosis, | ||
+ | typical inflammatory disease. | ||
+ | |||
+ | So if you want to study these diseases, you're going to be drawn | ||
+ | inexorably toward the study of the gene for ACE, for the | ||
+ | angiotensin converting enzyme. And it just so happens that a | ||
+ | number of bacteria act on that gene. But in particular, lactobacillus | ||
+ | and bifidobacteria, | ||
+ | bacteria, gut bacteria that are in the yogurts and other | ||
+ | supplements that some of us eat, these bacteria produce a number | ||
+ | of peptides that down-regulate the expression of ACE in the | ||
+ | human body. So that is known—that very common bacteria, which | ||
+ | nobody would argue are present in the human body, produce | ||
+ | peptides that down-regulate a gene that is a key gene in | ||
+ | understanding the diseases like myocardial infarction, Alzheimer' | ||
+ | renal disease, progression of SARS, and diabetes. | ||
+ | |||
+ | Therefore, if you're going to study those diseases, you have to | ||
+ | study these organisms as well as the host organism //Homo sapiens// | ||
+ | You're looking at a metagenome. You're looking at more than one | ||
+ | genome that has to be examined. Similarly, we have another one | ||
+ | down here, PTPN22, which is related to diabetes mellitus, | ||
+ | rheumatoid arthritis, and lupus (SLE). That one is known to be up- | ||
+ | regulated as part of the innate immune system' | ||
+ | mycobacteria. With a surge in latent tuberculosis, | ||
+ | increasing knowledge of // | ||
+ | in the population, it's very important, if you're going to study these | ||
+ | diseases, you need to study how that particular gene behaves in | ||
+ | the environment, | ||
+ | stimulated by mycobacteria, | ||
+ | species as well, that will be up-regulated, | ||
+ | again, we're expanding the metagenome that we need to study | ||
+ | when we think about disease. | ||
+ | |||
+ | Back a number of years ago I reported that sarcoidosis had | ||
+ | succumbed to an antibacterial therapy based on a VDR agonist. We | ||
+ | were actually able to reverse that disease process. And in the | ||
+ | subsequent five years, we put together an observational cohort of | ||
+ | over 500 human subjects with a whole variety of different | ||
+ | diagnoses. And we went on to demonstrate the reversibility of | ||
+ | many autoimmune diagnoses. | ||
+ | |||
+ | This is from a paper that was presented at the Sixth International | ||
+ | Congress on Autoimmunity just two months ago in Porto, Portugal. | ||
+ | We have listed here a number of autoimmune diagnoses which | ||
+ | responded to an antibacterial therapy which involved a VDR | ||
+ | agonist, a small molecule called a VDR agonist. We start at | ||
+ | Rheumatoid Arthritis, Hashimoto' | ||
+ | type 2 Diabetes, Sjogrens', | ||
+ | number of cases, which were in Diabetes Insipidus. In general, | ||
+ | between 18 and 53 months of treatment, 81% of the cohort | ||
+ | experienced reduced disease symptoms with an antibacterial | ||
+ | therapy involving a small molecule VDR agonist. | ||
+ | |||
+ | But this is the surprising thing. [The therapy was also effective | ||
+ | against] Chronic Fatigue Syndrome/ | ||
+ | osteoporosis, | ||
+ | deficiencies. At Karolinska earlier this year there was a conference | ||
+ | on cognitive deficiency in disease, and we gave papers showing | ||
+ | that both CFS and cognitive deficiencies were directly related to | ||
+ | inflammatory diseases and, chemically, some of the links. | ||
+ | Obsessive Compulsive Disorder, Bipolar, and memory loss—things | ||
+ | that we don't think to be associated with inflammation—these also | ||
+ | disappeared as the chronic inflammatory condition—the primary | ||
+ | inflammatory condition, rheumatoid arthritis, SLE, whatever— | ||
+ | disappeared. | ||
+ | |||
+ | Now what we have done, we have identified, back around the turn | ||
+ | of the century, an intraphagocytic metagenomic microbiota, and | ||
+ | we described the method by which it evades the immune system. | ||
+ | And that's where this small molecule comes in. So, firstly, a | ||
+ | number of groups in the past had identified that there were | ||
+ | microbiota, or communities of microbes, that lived inside the cells. | ||
+ | There are many studies; I'll show you one in a while. But what we | ||
+ | did was, we said, “Right, but how do you deal with those? What do | ||
+ | they do? How do they evade the immune system to persist inside | ||
+ | phagocytes? | ||
+ | |||
+ | I mean, phagocytes are supposed to be the body's defense against | ||
+ | persistent infection. What we found was that the genomes in this | ||
+ | metagenome, in the microbiota, the biofilm, if you like, the | ||
+ | genomes accumulate gradually during life, incrementally shutting | ||
+ | down the innate immune system. And, depending on the | ||
+ | environment to which you are subjected, which pathogens you | ||
+ | become subjected to during life, the metagenome will gradually | ||
+ | build up during life. Eventually, genes from the accumulated | ||
+ | metagenome will determine a clinical disease symptomatology or | ||
+ | just a disease of the aging. | ||
+ | |||
+ | The microbiota is located in the cytoplasm of nucleated cells. | ||
+ | Therefore it has access to both the DNA transcription and to the | ||
+ | protein translation machinery of //Homo sapiens//. In addition, and | ||
+ | this is very important for those of you who are studying mutations, | ||
+ | the host DNA repair mechanisms are susceptible to modification by | ||
+ | “junk” from the metagenome. | ||
+ | |||
+ | Well, what does the microbiota look like? This is light microscopy. | ||
+ | This is a monocyte with a very highly infected cytoplasm. You can | ||
+ | see the nucleus, there' | ||
+ | effectively exploded from expansion of the pathogens in it and | ||
+ | thrown out dozens of these tiny, tiny transparent tubules, which | ||
+ | stain for bacterial DNA. You can see them along here; there' | ||
+ | probably 20 sub-microscopic bacteria tubules through there, in the | ||
+ | infected cytoplasm and the nucleus. Look at the length of these | ||
+ | tubules. This is about 20 cells long, this one is, absolutely huge. | ||
+ | This is optical microscopy of live blood, aged between 6 and 36 | ||
+ | hours on a microscope slide, untreated other than that, just live | ||
+ | blood aged on a microscope slide. It was taken on a Chronic | ||
+ | Fatigue Syndrome patient using a Bradford microscope by Dr. Andy | ||
+ | Wright in Manchester. | ||
+ | |||
+ | Now there was a TEM study done (Transmission Electron | ||
+ | Microscopy) in 1989 at Columbia University by Emil Wirostko and | ||
+ | his colleagues. And he looked at the phagocytes, all of the | ||
+ | phagocytes, actually, from a number of diseases. He looked at | ||
+ | Crohn' | ||
+ | at sarcoidosis. And he took the phagocytes from the eyes of these | ||
+ | patients, and was therefore able to image them very well with TEM | ||
+ | microscopy. And what he found was a number of artifacts inside | ||
+ | the cytoplasm which stained for bacterial DNA. This is the stain; | ||
+ | unfortunately, | ||
+ | not enhanced at that point. Then there are also very small tubular | ||
+ | structures, transparent tubular structure throughout the cytoplasm, not unlike what we were seeing on the other side, but | ||
+ | not nearly so heavily developed, so heavily parasitized. And here, | ||
+ | of course, you've got the nucleus, and the nucleus itself is starting | ||
+ | to break apart and become weak as well. This was from a juvenile | ||
+ | rheumatoid arthritis patient. | ||
+ | |||
+ | The important thing is to understand how the microbiota persist. | ||
+ | Because it's one thing to understand that a microbiota must be | ||
+ | present, that it is present, but you can't do anything about it until | ||
+ | you understand how it evades the immune system. That was the | ||
+ | breakthrough we made back around 2003. We looked at the | ||
+ | nuclear receptors. The nuclear receptors are a family of very | ||
+ | complex proteins—transcription factors—that transcribe DNA for | ||
+ | many of the key functions of the human body. For example, the | ||
+ | progesterone receptor, the estrogen receptor, the androgen | ||
+ | receptor, the glucocorticoid receptor are all nuclear receptors. | ||
+ | And there' | ||
+ | is very important for the innate immune system of //Homo sapiens// | ||
+ | because it transcribes the genes for the Cathelicidin and beta- | ||
+ | Defensin anti-microbial peptides. The primary way that phagocytes | ||
+ | themselves protect themselves against pathogens is with | ||
+ | Cathelicidin, | ||
+ | and the transcription of those genes, is essential to intra- | ||
+ | phagocytic innate immune defenses. | ||
+ | |||
+ | This microbiota evades the human immune system by blocking | ||
+ | DNA transcription by the VDR, which consequently blocks | ||
+ | expression of these endogenous anti-microbials. In addition, the | ||
+ | microbiota changes the expression of the 913 or more other genes | ||
+ | that are transcribed by the VDR, particularly including MTSS1. | ||
+ | MTSS1 is the Metastasis Suppressor number 1 that gives rise to | ||
+ | the protein called “Missing in Metastasis.” And when the bacteria, | ||
+ | the microbiota, knocks out the VDR, that is one of the other 913 | ||
+ | important genes in the body that get knocked out as well. | ||
+ | |||
+ | The homeostasis of other Type 1 nuclear receptors is also indirectly | ||
+ | upset by the pathogens. The VDR, PXR (the Pregnane Xenobiotic | ||
+ | Receptor), the Glucocorticoid Receptor, the Thyroid-alpha-1 and | ||
+ | Thyroid-beta-1 are all Type 1 receptors which are upset when the | ||
+ | VDR is knocked out by the microbiota. In particular, when the | ||
+ | Glucocorticoid and Thyroid Receptors are knocked out, then we | ||
+ | end up typically with diagnoses of hypothyroidism and adrenal | ||
+ | insufficiency. We've demonstrated that both are reversible, once | ||
+ | the inflammatory disease can be reversed. | ||
+ | |||
+ | Well, why has the microbiota been ignored? There are a couple of | ||
+ | reasons. The first one is that VDR homology—the shape, the actual | ||
+ | proteins, the amino acids that fit together to make the human | ||
+ | VDR—VDR homology has evolved between the species in such a | ||
+ | way that the VDR of //Homo sapiens// transcribes different genes | ||
+ | from the VDR of other mammals. In particular, the VDR from the | ||
+ | murine and canine genomes, which is what we've most generally | ||
+ | studied when we've been studying diseases, doesn' | ||
+ | Cathelicidin or the Defensins. So if the microbiota knocks out the | ||
+ | VDR in the murine or canine genomes, it cannot persist. The | ||
+ | phagocytes will get it, because the Cathelicidin and Defensins are | ||
+ | transcribed by different receptors in other genomes. It's only | ||
+ | //Homo sapiens//, and one or two of the other major primates, where | ||
+ | the VDR transcribes cathelicidin. | ||
+ | |||
+ | So a human metagenomic microbiota will not survive when it' | ||
+ | transfected into a mouse. Koch's Postulate fails. Different species | ||
+ | and different mutations would be necessary if the microbiota was | ||
+ | to knock out the different gene pathways needed for survival in a | ||
+ | mouse. Of course, you would know from evolutionary statistics | ||
+ | that the likelihood of a pathway developing in other mammals and | ||
+ | other animals is high. And indeed, there was a conference a month | ||
+ | ago from the American Association of Microbiology in San Diego | ||
+ | where a presentation was given by the Max Planck Institute in | ||
+ | Germany, who have just found the same microbiota, the same | ||
+ | biofilm inclusions, in the phagocytes from worms that were | ||
+ | recovered from barrier reefs, from coral reefs. So it's pretty certain | ||
+ | that other species have developed, that microbiota have developed | ||
+ | so that they can overcome the immune system of other species, | ||
+ | but it's a different mechanism to the one that they use to | ||
+ | overcome man. | ||
+ | |||
+ | Now, secondly, the microbiota is only stable in-vivo. It defies | ||
+ | extraction using standard techniques. You saw what happened with | ||
+ | that blood that was just aged under a slide. If you try to extract | ||
+ | the cells, cells that are infected disintegrate. It's very, very difficult | ||
+ | to culture or to identify these pathogens //in vitro//. But you can do it | ||
+ | using DNA shotgun techniques. You can take the DNA from Homo | ||
+ | sapiens, and you can actually use shotgun techniques, the same | ||
+ | way as we decode the human genome or the bacterial genomes, to | ||
+ | figure out what genomes are there. And because we now have a | ||
+ | roadmap of the 1000+ bacterial genomes, when we find DNA from | ||
+ | those genomes in our human sample, we can say, “Aha! We’re | ||
+ | looking not only at human DNA in our shotgun sequencing, we are | ||
+ | looking at bacterial DNA as well, and probably from X species”, one | ||
+ | of the 1078 that we have defined. | ||
+ | |||
+ | This is a study that was done by Dempsey, et al, that actually used | ||
+ | 16S RNA rather than shotgun, but it doesn' | ||
+ | infected prosthetic hip joints, which were removed during revision | ||
+ | arthroplasty, | ||
+ | removed hip joints. And these are the species that they found in | ||
+ | that biofilm, removed from people. // | ||
+ | that you expect to find in a biofilm, had about 44% of the clones | ||
+ | sequenced and about 60% of the clones analyzed. | ||
+ | |||
+ | Methylobacterium, | ||
+ | aureus actually, in biofilms, and it’s there. Proteus, look at | ||
+ | this—hydrothermal vent Eubacterium was present at a little bit | ||
+ | higher number [percent] of clones [sequenced] as // | ||
+ | The iron-oxidizing lithotroph—a number of species here that | ||
+ | nobody dreamed existed in man until we were able to use | ||
+ | molecular gene technologies to figure out that, “hey, what we’re | ||
+ | looking at is not //Homo sapiens//. It’s not anything we’ve looked at | ||
+ | before.” The computer matches it up with DNA from hydrothermal | ||
+ | vent Eubacterium. | ||
+ | |||
+ | Until the genome was cracked, we only had the postulates of Koch | ||
+ | as a guide. Koch, in 1897, produced a set of postulates which | ||
+ | defined when you could claim that an infectious disease was | ||
+ | present. They caused us to search for a singular pathogenic | ||
+ | species, because the postulates of Koch said, “one bug, one | ||
+ | disease,” and sidetracked science from understanding the | ||
+ | horizontal transfer of DNA within the microbiota. Science became | ||
+ | fixated on co-infections, | ||
+ | knock out, but which we could culture, we could observe, and we | ||
+ | missed the primary disease mechanism—the metagenome. | ||
+ | |||
+ | The other reason that this has escaped study by science is that the | ||
+ | VDR stands for Vitamin D Receptor. It is activated by a substance | ||
+ | which we know as Vitamin D, which is a transcriptional activator, a | ||
+ | secosteroid. Vitamin D is not a nutrient. There is a very complex | ||
+ | control system by which 7-dehydro-cholesterol is synthesized into | ||
+ | 1, | ||
+ | VDR nuclear receptor. There are multiple feedback pathways, there | ||
+ | is transcription of degrading enzymes, there is trans-repression of | ||
+ | an enhancing enzyme, and then, via the PXR (the Pregnane-X | ||
+ | Receptor), other enzymes are affected and finally this primary | ||
+ | CYP27B1 second hydroxylation enzyme is activated by PKA | ||
+ | P300/CBP pathway—very complex mechanism, which you would | ||
+ | expect. It's at the heart of innate immunity. A paper we published | ||
+ | this year goes into the control system in some detail. | ||
+ | And this is the interesting thing. Here's //in silico// technology. We' | ||
+ | taken the X-ray structure of the VDR, actually a number of VDRs | ||
+ | from different groups, and we've docked the various types of | ||
+ | Vitamin D, the various hydroxlations, | ||
+ | of them has the 1-alpha-hydroxylation here, which is capable of | ||
+ | activating transcription. But all of the others overlay the same | ||
+ | region in the receptor. In other words, they are antagonists for | ||
+ | that transcription process. | ||
+ | |||
+ | If we take the VDR agonist which we have found, which is a drug | ||
+ | called olmesartan, we see here olmesartan in the human VDR. This | ||
+ | is a molecular dynamics emulation using a large computer array | ||
+ | computing real-time atomic force interactions, | ||
+ | all proteins, everything is in motion, there' | ||
+ | time. And here we have a rat VDR with the same drug in it. Now | ||
+ | what's particularly interesting is the orientation of the tetrazoles | ||
+ | and the functioning of the drug is different in the two VDRs. If you | ||
+ | look at that tetrazole orientation and the other one, they' | ||
+ | different—there are 7 hydrogen bonds there, and there are only 5 | ||
+ | hydrogen bonds in the VDR of a rat. So the drug itself doesn' | ||
+ | behave in the same way in the VDR of the rat versus the VDR of | ||
+ | the man. | ||
+ | |||
+ | Here is a basic problem that we have missed in our biological | ||
+ | sciences. We have missed trying to go to the level of the gene and | ||
+ | understand the difference between species. And we have assumed | ||
+ | that any mammalian species is a reasonable emulation of Homo | ||
+ | sapiens’ genome. | ||
+ | |||
+ | The other thing that you can do to go after the microbiota is to use | ||
+ | low-dose antibiotics which block protein synthesis. Proteins that | ||
+ | create biofilms that protect the community can be attacked by a | ||
+ | number of simple antibiotics. | ||
+ | |||
+ | This one is azithromycin and the 50S side of the ribosome, the | ||
+ | protein translation area of the ribosome, and you can block the | ||
+ | ribosome. The rate of bacterial death is controlled by inhibiting | ||
+ | protein synthesis in the 70S bacterial ribosome using sub- | ||
+ | inhibitory, low doses of bacteriostatic antibiotics. We’re talking | ||
+ | about very low doses here, where azithromycin—typically patients | ||
+ | with inflammatory disease once you activate the VDR, those | ||
+ | patients can only withstand one tenth of the normal dose of | ||
+ | something like azithromycin. One bacterium is weakened if just | ||
+ | one antibiotic is bound into one ribosome. | ||
+ | |||
+ | So intermittent, | ||
+ | bacterial death. We can control the rate of bacterial death by using | ||
+ | the protein synthesis inhibitors, and that is just as well, because | ||
+ | there is a phenomenon called “immunopathology.” | ||
+ | |||
+ | Immunopathology is the damage done to the rest of the body | ||
+ | when the immune system is doing its job. When the immune | ||
+ | system is phagocytosing dead cells, phagocytosing pathogens, | ||
+ | then it releases a cytokine storm, it release chemokines, it | ||
+ | activates the nuclear factor Kappa-B pathway, all of the normal | ||
+ | ways that the body signals amongst itself that something is | ||
+ | desperately wrong. When you start allowing the human immune | ||
+ | system to find the huge bacterial load we’re carrying, ten times | ||
+ | the number of bacterial cells to human cells (that' | ||
+ | number), then the immunopathology can become life-threatening. | ||
+ | The loss of cells, the cytokine storm, has to be controlled, so it | ||
+ | doesn' | ||
+ | low dose antibiotics, | ||
+ | spread the therapy over many years. | ||
+ | |||
+ | There is one other way that we can visualize the metagenome—the | ||
+ | way that the human experience is a metagenome, the product of | ||
+ | many, many genomes working in tandem. Now I pointed out | ||
+ | earlier this //E. coli// glucose metabolism, and what I was pointing out | ||
+ | to you there was that a lot of the products that are produced, | ||
+ | fructose-6-phosphate for example, and [it is] very common in both | ||
+ | //E. coli// and the human genome. Both produce those substrates. But | ||
+ | there are some of the substrates, some of the proteins that are | ||
+ | produced by //E. coli//, which I called “junk” earlier on in one of my | ||
+ | other slides, but they are exudates, they are by-products of the | ||
+ | bacterium itself, working. And there are some of those that are | ||
+ | unique. And we can use mass-spectroscopy to image them. | ||
+ | |||
+ | At the Imperial College in London that is what they’ve been doing. | ||
+ | They’ve come up with a concept called the “metabolome”—the | ||
+ | Human Metabolome—or the spectrum of metabolites that is | ||
+ | associated with //Homo sapiens//. And for my final slide I want to look | ||
+ | at this particular image which is from Dumas, et. al., in Analytical | ||
+ | Chemistry, 2006. What Jeremy and his colleagues at the Imperial | ||
+ | College did here was to take those non-human metabolites that | ||
+ | were present in urine, and they produced a method of displaying | ||
+ | on a two-dimensional surface, the specific measures of those non- | ||
+ | human metabolites in such a way that you could see that different | ||
+ | populations were producing different metabolites. So the American | ||
+ | population has different non-human metabolites in its urine to the | ||
+ | Japanese, to the Chinese—a very large number, about 1000 | ||
+ | patients. And you could see that, due to their environment, | ||
+ | their food, due to everything that is associated with their | ||
+ | metagenome, these three populations are different, and we can | ||
+ | measure the way that their bodies are operating differently. | ||
+ | |||
+ | One particular artifact which you can just see here, you can just | ||
+ | see a violet number stuck here in the American group. There were | ||
+ | actually five Japanese that moved to America. When they did that, | ||
+ | their metabalomes suddenly took on the American characteristics | ||
+ | rather than their native Japanese characteristics. In other words, | ||
+ | it’s environmental factors that drive our metabolome. So that’s my | ||
+ | final thought—always remember the metagenome. The human | ||
+ | experience is based on a metagenome—ten times as many | ||
+ | bacterial cells in the human body as human cells is the current | ||
+ | estimate. Over the next ten years we'll be able to firm up exactly | ||
+ | what that number is and exactly what the function of those—I | ||
+ | hesitate to call them pathogenic—let me call them symbiotic cells | ||
+ | rather than pathogenic cells. | ||
+ | |||
+ | Thank you very much. | ||
+ | |||
+ | Q: I'm from India, [inaudible] and I've been working since a long | ||
+ | time with the bacterial pathogens as well as the human genome | ||
+ | relic [inaudible]. | ||
+ | |||
+ | So, my question is very relevant to MHC gene, Major | ||
+ | Histocompatibility Complex gene, in relation to bacterial | ||
+ | pathogens. How they actually react, I do not understand actually, | ||
+ | even today, how the Major Histocompatabilty gene would actually | ||
+ | function with pathogenic and non-pathogenic selectively of the | ||
+ | microbes which are living in our system. And that is [they are] the | ||
+ | queries that I wanted to ask you, whether you have something in | ||
+ | relation to MHC and human pathogenicity as well as the | ||
+ | microbiome infection and how they actually [interact]... | ||
+ | |||
+ | A: I don't have a micro-answer, | ||
+ | answer is: we're dealing with approximately one thousand genes, | ||
+ | which are estimated to be in the human body, compared to the | ||
+ | 25,000 genes of //Homo sapiens//. When there is interaction, | ||
+ | you would definitely have in the cytoplasm of nucleated cells, | ||
+ | where there is interaction, | ||
+ | one protein affecting MHC, it is on a number of proteins and | ||
+ | enzymes and, in fact, also small molecules from multiple species | ||
+ | affecting MHC. Because MHC is so important to the adaptive | ||
+ | immune response, you can expect that the pathogens are going to | ||
+ | have to develop some way of overcoming the adaptive immune | ||
+ | response and therefore, some way of mutating, under-expressing, | ||
+ | or whatever, the MHC. | ||
+ | |||
+ | So the macro answer is: we don't know, but it makes sense. The | ||
+ | micro answer is: we don't know. | ||
+ | |||
+ | Q: Actually, this is a very interesting new phenomenon— | ||
+ | discovery—that, | ||
+ | compatible with the Apple system. But now gradually, the two | ||
+ | systems, they have some micro-programs that can be integrated | ||
+ | with one another. Would that be possible, that the microorganism' | ||
+ | genome can, sometimes, in some mechanism—can dynamically | ||
+ | integrate directly with the human genome? | ||
+ | |||
+ | A: Well, we have done that randomly. In the past there have | ||
+ | been… For example, smallpox vaccination was very strong at one | ||
+ | point in history. Polio vaccination with the different vaccines, for | ||
+ | example, has been different for different generations of people | ||
+ | living today. So, we have actually done that. We have also used | ||
+ | BCG, a live vaccine, for example, in trying to combat tuberculosis. | ||
+ | And we know BCG is related to causation of other diseases, | ||
+ | sarcoidosis being one of them that is up-regulated by BCG. So, | ||
+ | randomly we have sort of done that. | ||
+ | |||
+ | But at this point we have no idea [of] how to introduce another | ||
+ | genome in order to try and make the metagenome on the whole | ||
+ | positive rather than being negative. The Phage therapy, that was | ||
+ | very popular in Russia and in Eastern Europe, for example, is, in | ||
+ | many ways, a way of trying to change the metagenome in such a | ||
+ | way that it wasn't harmful, [so that] it wasn't making the harmful | ||
+ | substances anymore. And in the short term it worked reasonably | ||
+ | well, but in the long term it didn't produce very much extended | ||
+ | longevity or any of the things that you would expect from it. Does | ||
+ | that answer your question? | ||
+ | |||
+ | Q: Yes. But from the perspective of retrovirus, there are retrovirus | ||
+ | genomes integrated into our human genome from time to time, | ||
+ | like HIV. | ||
+ | |||
+ | A: Yes, very common, in the telomeres, from our early study into | ||
+ | the telomeres and then working upwards. And if you look into | ||
+ | these sicknesses, the inflammatory sicknesses, the rheumatic | ||
+ | diseases, the telomeres are different, they are ragged. There is | ||
+ | something going on there that we don't understand yet, and that' | ||
+ | where we have got to start looking. | ||
+ | |||
+ | Q (last question): | ||
+ | is for me a completely new world, [a] novel concept. I mean, we | ||
+ | are trying to use a lot of the TLR ligands as our adjuvants. | ||
+ | But on the other hand, you are telling us that we are full of | ||
+ | bacteria all over, so we should be hypersensitive or sort of tolerant, | ||
+ | but we still use the TLR ligands and we get very strong responses. | ||
+ | So how do you put this together? Because you show—I | ||
+ | remember the gene—that inside of our cells we have a protective | ||
+ | gene not to be [to keep us from being] hypersensitive. | ||
+ | |||
+ | So how do you put this together while still [bearing in mind that | ||
+ | our patients] respond very well like [to] CPG, flagelin, or whatever, | ||
+ | other TLR ligands? | ||
+ | |||
+ | A: Well, if you look at autoimmune disease in general, the focus in | ||
+ | autoimmune disease research for the last five decades, the last | ||
+ | half century really, has been on the adaptive immune response, on | ||
+ | the things we observe, on the antibodies. And one of the diseases | ||
+ | that I mention there, Chronic Fatigue Syndrome—which is thought | ||
+ | to be a neurological disease or just a psychosomatic disease by | ||
+ | some physicians—but there are actually distinct antibodies which | ||
+ | were identified in CFS patients. This was reported at the Porto 6th | ||
+ | International Congress in September [2008]. | ||
+ | |||
+ | Because what happens, is when the innate immune system fails, | ||
+ | you get a cytokine cascade and a chemokine cascade which signals | ||
+ | to the adaptive immune system that something is wrong. And it | ||
+ | tries to figure out what is wrong. It tries to take the fragments of | ||
+ | whatever is available, whatever DNA has been left after | ||
+ | phagocytosis and figure out what to do with it. | ||
+ | |||
+ | And when we think that we are producing antibodies to the human | ||
+ | body itself, we are actually producing antibodies that is [are] the | ||
+ | adaptive immune system' | ||
+ | looked like. But because we have not identified the pathogens | ||
+ | enough yet, at the level of the gene, at the level of the DNA, we | ||
+ | don't realize that we are looking at a pathogen. | ||
+ | |||
+ | You would know that antibodies, for example, are very non- | ||
+ | specific. A typical antibody will react to anything from a range of | ||
+ | small molecules right up to a number of larger proteins. Some are | ||
+ | very specific but very few are very specific. So if you look at the | ||
+ | adaptive immune system, it is downstream from the innate | ||
+ | immune system failure. And we have just always assumed that the | ||
+ | innate immune system just worked and it hasn't been just | ||
+ | working. It's been gradually getting worse and worse in its | ||
+ | operation, particularly during the last century. Although these | ||
+ | diseases have been around… The Neolithic Iceman that was dug up | ||
+ | in Austria/ | ||
+ | and also arthritis, which are the same diseases. So it looks as | ||
+ | though a metagenome has been around for quite a long time, just | ||
+ | changing, as each successive generation comes along. | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | ===== Appraisal of talk by Personalized Medicine ===== | ||
+ | |||
+ | In his article, "A New Series of International Genetic Congresses Take Place in China," | ||
+ | |||
+ | < | ||
+ | |||
+ | // | ||
+ | </ | ||
+ | |||
+ | {{tag> |