This was a very exciting lecture by Arup K. Chakraborty called Understanding Adaptive Immunity: A crossroad of the physical, life, and engineering sciences. Most of the material was beyond ordinary mortals’ grasp but this audience was not make up of ordinary people and as I looked around occasionally it was obvious that everyone was paying rapt attention and sitting on the edge of their seats. There were vast amounts of technical data but it seemed to come down to an infectious organism forming its own unique antigenic peptides. These peptides were caught and presented on an MHC molecule snagged onto the antigen presenting cell which when combined with the thymus glands TCR molecule, being provided by the thymus, and were able to identify, with high precision, if the binding energy on the peptide was within the critical limits which were able to defined self and non-self. If these antigens failed to present themselves as being of-the-self they were ripped apart into their constituent more primitive parts. There were positive and negative feedback interactions which mediated these processes. Many of these critical interactions in this process took place within the thymus gland and others externally with the glands generated T-cells. (That is my feeble attempt to explain in a few words what an entire brilliant scientific community has spent huge quantities of time, effort and money trying to understand and explain.)
Chakraborty didn’t dwell upon it but he mentioned that there was a temperature mediated quality to these reactions, at least in their laboratory settings for testing the reactions. That was the part of the lecture that interested me most because I have been watching temperature interactions of various disease processes. That interest was mentioned a few days ago in my blog about David Julius’ lecture, Temperature triggers biological responses, and some thoughts stimulated by it:
“That was a general overview of the lecture but what follows are my speculations on what it might mean as to why I have been having observable effects from my “experiments” with temperature as described in. 1. Poison Oak, Poison Ivy itching cured with hot air, 2. A cure for the common cold using 105°F baths. 3. Cure the common cold with 102°F voluntary fevers, 4. Prevent the common cold with capsaicin, 5. Fever kills cancer by triggering the body’s defenses. Each of these treatments for a physical health problem may have been working because the heat-related stimuli were triggering a response in some appropriate bodily system.”
Another possible relationship to bodily heating was referred to in How to revive cold-dead people by warming their heart, where it was suggested that people whose body temperature had dropped to 60°F were revived because their heart was warmed and started beating before the rest of the body was warmed. The dead person was revived because their heart was warmed and demanding more blood before the rest of their body was warmed and it demanded the blood. When the other parts of the body demanded blood it deprived the heart of some blood and so it was unable to supply all the requirements and because the heart became overtaxed and wasn’t supplying enough blood to itself it failed. With near dead “cold-dead-people” and near dead famine-dead-people the heart must be given absolute priority in the revivification processes. Whole body warming of a cold-dead person or whole body feeding of a famine-dead person kills them because the heart is over-taxed and fails.
Here is a speculation: perhaps, because the thymus is so close to the heart it was warmed also in these miracle cold-dead revivification events and that warmed gland exerted some as yet unknown influence. Generally speaking evolution has placed our most vital organs in the most protected places within our bodies. Thus, it might be assumed, from that developmental eventuality that the thymus was a very critical organ and the maintenance of its optimal operating temperature near our central core zone was critical to our survival.
After a couple of billion years of evolution those things which worked best are the ones that have been retained as near their optimum operating conditions as possible.