Multiple Sclerosis: Brief Summary1) Attacks by T-Lymphocytes scar myelin sheaths in brain and spinal cord.2) Abnormal antibodies are found in cerebrospinal fluid (implying abnormal B-lymphocytes). (These abnormal antibodies are called "oligoclonal bands") 3) First attack typically occurs suddenly between ages 20 to 40; Then gradual recovery; than a delay of several years; then another sudden, severe attack on a different part of the brain, then another gradual and incomplete recovery; and then another attack, and another, and another, coming closer together. (Many people have steadily worse attacks, without relapses). 4) The name (MS) refers to multiple hardened scars visible in autopsies; discovered and named in France & Germany in the late 1800s. 5) Locations of attacks are visible by Magnetic Resonance Imaging, and are shown in a time lapse film in the Wikipedia article on MS. Elliptical, egg-shaped, 1 or 2 centimeters in diameter, with sharp boundaries (not blurred edges, not star shaped, as might instead have been expected for attacks along nerve axons.) 6) About one person in a thousand gets MS, but this rate is lower in the south in the USA, and in southern Europe. In South America and Australia, rates are lower in the north. These differences in rates are based on where a person lived from birth to age 15. (!) Hypotheses include lack of UV & Vitamin D, Scandinavian genetic predisposition, or some protective effect of tropical diseases. The rate is 3 times higher in New York than North Carolina. (Related to hygiene theories of allergy? Us southerners being messy?) MS incidence is higher in people who had a diagnosis of infectious mononucleosis (Epstein-Barr virus) before age 20. Nearly all adults have antibodies to EBV, but only a small percentage have had recognizable cases of mono, nearly all of them as teenagers or young adults in countries with good hygeine. Children in tropical countries typically have antibodies to EBV by age 5. Is early, undetected, infection with EBV protective for MS, or is it that late infection predisposes to MS? 7) Identical twins of persons with MS have about a 1/3rd chance of getting MS also. Rates are also higher in other relatives, but more in the range of 2%. 8) Geneticists cannot find any particular gene, or combination of genes; The cause is believed to be some combination of genes and environment. (e.g. those other 2/3 rds of twins were not exposed to some unknown trigger.) 9) Autopsies and MRI have revealed many cases in people who were not diagnosed. So the true rate may be 50% higher, or more? 10) Twice to 3 times as common in women as men. Nearly all autoimmune diseases have higher rates in women. In Lupus, the rate is 9 or 10 times higher. This is "explained" by a supposedly slightly stronger immune system in female mice, etc. but there are many other possibilities. 11) Whether women have had children, or not, does not change the probability of MS. Pregnancy seems to delay worsening of symptoms. 12) Current treatments are corticosteroids (which suppress the whole immune system), a monoclonal antibody against a certain cell-matrix adhesion protein used by leucocytes, beta interferon (which causes severe flu-likr symptoms for as long as you take it), a random copolymer of 4 amino acids, & cancer chemotherapy poisons like cyclophosphamide. 13) Historically, arsenic, mercury, silver, quinine, nicotinic acid, fevers induced by malaria, electric shocks, hot baths, and hundreds (or thousands) of other treatments were tried, and claimed for a while to be effective. 14) Notice that the pattern of alternating attacks and remissions causes treatments to seem to be much more effective than they really are, and shows why tests of placebo treatments are essential. 15) For example, the main British charity for MS research and treatment broke up into bitter factions in the 1930s because of debates about methods of treatment and strategies of research. 16) I have read as many reports and summaries as I could find about what research is funded by the US Society for MS, and the only pattern I can discern is that they give big grants to good biologists who have made important discoveries in molecular biology, and hope something will turn up. Regeneration of oligodendrocytes is a current enthusiasm. 17) Tremendous amounts of detailed information, and random treatments, with few or no general principles, general strategies, & slow to nil improvements in effectiveness. That is the history of this disease; and history seems to be continuing in the same patterns. TOPICS FOR CLASS DISCUSSION A) If a time machine came back from the future with a list of 100 different theories about what causes MS (one of which is correct, & the other 99 were designed to deceive us), then I believe we could quickly figure out which is the correct cause, based on information we now have. B) Imagine if we sent back to 1950, nine fictional explanations of genes, plus the one correct explanation. Would scientists have been able to deduce which of the 10 was true? C) Which scientist would have been the most likely, or quickest, deducing the answer? D) What do your answers to these last 2 questions suggest about how to cure MS? E) Does what you read in "The Double Helix" suggest any good strategies for curing MS? F) What can substitute for that time machine from the future? G) Would it help if people regarded different autoimmune diseases as having as much in common with each other as they consider cancer to be basically one disease? H) Einstein is supposed to have said that imagination is more important than knowledge, although somebody may have just imagined this. I) Your ideas on MS and how to cure it are just as valuable as the current experts. J) Another good question to discuss is how to test theories and treatments for MS. And incidentally... The Wikipedia article on MS is ten times as good as either the NIH or the MS Society web sites. The two British MS societies have good web sites. All of them tend to say "It it is not yet completely clear..." about questions where nobody has a clue, and then doubting whether MS is an autoimmune disease because the key antigen is uncertain. Notice how difficult it is to know how sure to be about many medical phenomena. ducated public? ("sounds strange", indeed.)
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