[HN Gopher] Mimicking the cells that carry hemoglobin as a blood...
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       Mimicking the cells that carry hemoglobin as a blood substitute
        
       Author : rbanffy
       Score  : 84 points
       Date   : 2024-07-05 14:10 UTC (8 hours ago)
        
 (HTM) web link (www.science.org)
 (TXT) w3m dump (www.science.org)
        
       | ompogUe wrote:
       | Reminds me of something I read in one of the Kurzweil books years
       | ago: having nano-blood delivering enough oxygen to stay
       | underwater for 8 hours. Things like that.
       | 
       | The (funny to me) idea that also came from that was that we can
       | remove our digestive systems, because "eating mainly for
       | nutrients" turns into "eating just for enjoyment", and we have a
       | tray in our stomachs that we tap out to empty the chewed food.
        
         | sottol wrote:
         | At that point, why not just let Neuralink tickle the right
         | brain regions - seems more sensible than literally stuffing
         | food into your mouth. Also seems closer to being achievable
         | than nano blood.
        
           | jayd16 wrote:
           | Heroin just doesn't have the same experience as a meal.
        
           | ertgbnm wrote:
           | Same reason we might choose to have sex instead of
           | masturbate. Masturbating may be faster and easier. But sex is
           | fun and you can do it with friends.
        
           | 0cf8612b2e1e wrote:
           | Nano specifics aside, we can already feed people
           | intravenously. We do not yet know how to electrically trick
           | the brain in any meaningful and safe way.
           | 
           | I might also be crossing the streams on partially remembered
           | text, but I believe the nano component of the blood was about
           | engineered hemoglobin that was a more effective oxygen
           | carrier, not glucose.
        
         | nonameiguess wrote:
         | There was a story here a few months ago from a guy who has
         | severe Crohn's disease, with his gut fused to some other organ
         | I can't recall in a way that prevented eating at all. He was
         | able to survive via a direct infusion of nutrients into his
         | blood, but the viscosity of the subtance would make it far too
         | painful to inject by any normal IV route, so he needed a
         | catheter inserted straight into his vena cava. And though this
         | provided all the sustenance his body required for energy,
         | because hunger hormones are produced in the gut, not eating
         | will leave you perpetually hungry even if you actually have all
         | the energy you need. The very existence of obesity should
         | probably make it obvious this is possible, but removing our
         | digestive systems may have unintended consequences. The way
         | this guy described his experiences sounded like a pretty
         | miserable existence.
        
           | LorenPechtel wrote:
           | I knew it had to into a major vein, but I didn't know about
           | the hunger issue with TPN.
        
           | krisoft wrote:
           | Yeah i mean realistically just the port to "a tray in our
           | stomachs" sounds like a nightmare. How do you make a port big
           | enough to take the tray out? How do you prevent it from
           | always getting infected? What do you do with the core muscles
           | where the tray port goes? How do you clean the pouch where
           | the tray resides? How will you make the tray-escophagus
           | interface leak proof? What if someone with the tray in their
           | stomach wants to do sports, or is in an accident? When they
           | are shocked around will the tray mechanism tear their flesh
           | and organs? Will the tray accomodate body shape changes
           | during a pregnancy? Or changes due to old age? How will
           | people know that their tray is full? Will they just start
           | choking? How big the tray has to be to accomodate a family
           | meal, but also be small enough to not feel as a burden during
           | everyday activities?
           | 
           | The truth is that our body is marvelously complex, and
           | dynamically adjusts to many challenges. It does this so
           | seamlesly that we don't even notice. That is why people come
           | up with ridiculous ideas like this because they are not
           | consciously aware of how amazing their body is at taking care
           | of the job of keeping them alive.
           | 
           | The closest to this tray idea in reality is an ileostomy. And
           | while it is better than dying, it has many risks and negative
           | consequences. The idea that otherwise healthy individuals
           | would willingly under go such a modification to their bodies
           | is ludicrous.
        
             | Rumudiez wrote:
             | Look up colostomy bags. It's not a lifestyle I think many
             | people would choose on a whim
        
               | epcoa wrote:
               | Not sure why you think someone mentioning an ileostomy
               | would be unfamiliar with colostomy bags.
        
           | tonetegeatinst wrote:
           | Iirc serotonin is also found in the gut.
        
             | Aurornis wrote:
             | Serotonin is found all over the body: Blood, digestive
             | system, skin, bones, lungs.
             | 
             | It doesn't migrate all over, though. Serotonin in the gut
             | doesn't go into your brain like many people assume.
        
               | jfengel wrote:
               | There has been research suggesting that the vagus nerve
               | might carry serotonin from the gut to the brain:
               | 
               | https://www.psychologytoday.com/us/blog/the-athletes-
               | way/201...
               | 
               | I'd note that this is a five year old article and I
               | haven't heard of any followups. And the article itself
               | may be misinterpreting the underlying actual research,
               | which suggests that it's more about SSRIs:
               | 
               | https://www.nature.com/articles/s41598-019-50807-8
               | 
               | Still, I thought it was worth mentioning.
        
           | somenameforme wrote:
           | In recent years the gut-brain axis [1] has been solidified as
           | both real, causal, and critical. So just removing your gut
           | would probably have severe consequences beyond just the more
           | straight forward ones.
           | 
           | [1] - https://en.wikipedia.org/wiki/Gut%E2%80%93brain_axis
        
             | TeMPOraL wrote:
             | The whole concept sounds a bit wooish, and the Wiki article
             | doesn't read like you'd expect it from a description of
             | "real, casual, and critical" concept in medicine. Is there
             | any other real set of factors that would make this
             | particular "axis" special, vs. a pair or triple of any
             | other organs that happen to be spaced far apart in the
             | body?
        
         | waltbosz wrote:
         | Just this morning I was wondering if one could cure their
         | hypertension by getting an artificial heart to circulate their
         | blood more efficiently.
         | 
         | I mean sure you could also treat with weight loss and regular
         | exercise, but it's a fun thought experiment.
        
           | carbocation wrote:
           | Hypertension is not caused by the heart pumping too well, so
           | this would not work for the purpose of curing hypertension.
           | But if you could invent a durable heart replacement therapy,
           | you'd save a lot of lives.
        
           | teaker wrote:
           | See, ECMO. Although it can save one's life where perfusion is
           | otherwise inadequate, it is extremely difficult to initiate
           | and maintain.
        
           | epcoa wrote:
           | If the pressures in a system are too high (mechanical or
           | biological) the pump is usually not the culprit.
        
         | nullorempty wrote:
         | It's not just the food it's flushing out.
        
       | jschveibinz wrote:
       | I am very familiar with the company KaloCyte that developed
       | Erythromer. Great technology, great people, good non-dilutive
       | funding, and they are pursuing a Series A.
        
       | abeppu wrote:
       | > Allan Doctor, a bespectacled 61-year-old physician-researcher
       | at the University of Maryland (UMD) School of Medicine
       | 
       | Not at all the point, but I get way too much enjoyment out of the
       | fact that this person is Dr. Doctor. I hope he occasionally
       | insists that people call him that and then quietly hums the song
       | by the Thompson Twins.
        
         | carbocation wrote:
         | Nominative determinism strikes again.
        
         | zimbu668 wrote:
         | In college the course on Maxwell's equations was taught by Dr.
         | Lord. Every time I walked in to class I thought "Let there be
         | light"
        
         | jorvi wrote:
         | Reminiscent of a Doctor Strange scene:
         | 
         | https://youtu.be/ewFg5wUvkGI?si=bxKgLot0iqwYpLx3
        
         | chriscjcj wrote:
         | When I was a little boy, the librarian at our small local
         | branch was named Virginia Read.
         | 
         | In the late 70's and early 80's, there were two doctors who
         | shared an office in San Luis Obispo, CA. Their names were Dr.
         | Herten and Dr. Payne.
        
         | ompogUe wrote:
         | Was reading yesterday about pioneering female ad-exec Mary
         | Wells Lawrence.
         | 
         | When she was passed up for a promotion, she started her own
         | agency, whose treasurer was "Richard Rich".
        
         | utensil4778 wrote:
         | I still can't get my head around the fact that one can earn a
         | doctorate in nursing.
         | 
         | Therefore: Dr. Nurse Doctor
        
       | brightball wrote:
       | Is that related to what that Humacyte company was doing? I
       | remember seeing it show up in the various politician stock trade
       | trackers that follow Pelosi, Tuberville, etc.
        
       | deegles wrote:
       | This is another company making the same product, they call it
       | OxyBridge https://virtechbio.com/
        
       | tonetegeatinst wrote:
       | I have a very very limited understanding of biology because I
       | never took anything other than a highschool class.
       | 
       | Is hemoglobin critical just because of its ability to deliver
       | oxygen to cells? If so could a synthetic replacement for
       | hemoglobin be developed that could replace to function of
       | hemoglobin in the human body? Or is this a issue of chemical
       | structure where our body would reject non hemoglobin molecular
       | structures attempting to deliver oxygen?
        
         | georgyo wrote:
         | Also not a biologist, but the the body actively rejects all
         | things it considers foreign.
         | 
         | Consider that we have A, B, O, and AB with both positive and
         | negative variants as the most common blood types.
         | 
         | Unless you're O+, you will reject the blood causing a massive
         | immune response.
         | 
         | Having the something that works like blood, the body won't
         | reject, and has a shelf life longer than actual blood is hard.
        
           | Kubuxu wrote:
           | AB+ is the universal recipient of red blood cells, O- is the
           | universal donor. It is reverse for plasma.
           | 
           | The blood rejection is reaction between blood plasma (with
           | cells produced by your immune system) and red blood cells.
        
         | utensil4778 wrote:
         | Mechanically, all hemoglobin does is take up an oxygen molecule
         | when in an oxygen rich environment, and releases it in a CO2
         | rich environment. CO2 just dissolves into the bulk fluid of the
         | blood and diffuses out in the lungs, it is not carried by
         | hemoglobin. However, hemoglobin _can_ bind to CO carbon
         | monoxide, and it can 't let go of it. The hemoglobin molecule
         | is effectively dead and useless.
         | 
         | If you had a molecule which functions in a similar way, it'd
         | probably work in blood. The real trick is getting it to release
         | the oxygen in the presence of CO2.
         | 
         | Immune response is a different matter that I don't know enough
         | about to weigh in on. I'd assume there's ways around it.
         | Possibly immunosuppressor drugs for the (hopefully) short time
         | you're on the synthetic blood.
        
         | dexwiz wrote:
         | It needs to collect and release CO2 and O2 at the correct times
         | and pressures. It needs to not be poisonous or toxic. It needs
         | to not be quickly processed by the liver or kidneys, but
         | processed enough that it doesn't build up and become toxic. It
         | needs to be evenly distributable via blood. It needs to not get
         | into places where it shouldn't be. It needs to not stick to
         | things like artery walls. It needs to not cause an immune or
         | inflammatory response. It needs to not cause you to clot or
         | bleed out. And it needs to do all this and more in disparate
         | parts of the body in varying chemical environments.
         | 
         | The list of requirements is very long. Out body evolved
         | alongside hemoglobin and finding a replacement that fits the
         | bill perfectly is very difficult.
         | 
         | Also hemoglobin appears in other places. Free oxygen is
         | actually toxic in large amounts and will oxidize random things.
         | Hemoglobin is used as an antioxidant to collect excess oxygen.
        
       | amelius wrote:
       | We will need this to rinse all the PFAS out of our blood
       | circulations.
        
       | westurner wrote:
       | Another solution; from "Scientists Find a Surprising Way to
       | Transform A and B Blood Types Into Universal Blood" (2024)
       | https://singularityhub.com/2024/04/29/scientists-find-a-surp... :
       | 
       | > Let's Talk ABO+: _When tested in clinical trials, converted
       | blood has raised safety concerns. Even when removing A or B
       | antigens completely from donated blood, small hints from earlier
       | studies found an immune mismatch between the transformed donor
       | blood and the recipient. In other words, the engineered O blood
       | sometimes still triggered an immune response._
        
       | isk517 wrote:
       | I did the math and unless I made a mistake, this $46M is a
       | smaller 'bet' by percentage of income than my yearly $6 bet on
       | the lottery.
        
       | EvanAnderson wrote:
       | A friend of mine did work in this space back in 90s and early
       | 2000s ("Synthetic Blood International", later renamed to "Oxygen
       | Biotherapeutics", now "Tenax Therapeutics") based on work done by
       | Dr. Leland Clark[0]. It sounded like really interesting stuff--
       | very sci-fi. They were using a fluorocarbon[1]. It made me think
       | of The Abyss.
       | 
       | They had a ton of interest from the Department of Defense.
       | 
       | Edit:
       | 
       | Oh, holy crap. I didn't realize Dr. Clark actually did the "rat
       | breathing liquid"[2] thing for real! (It sounds cruel, to be
       | sure...)
       | 
       | (Also, Dr. Clark had some serious Isaac Asimov sideburns going
       | on...)
       | 
       | [0] https://en.wikipedia.org/wiki/Leland_Clark
       | 
       | [1] https://patents.google.com/patent/US4289499A/en
       | 
       | [2] https://cen.acs.org/articles/83/i13/LELAND-CLARK.html
        
       | yalogin wrote:
       | This is exactly the kind of bets the government should make.
       | However I was expecting it to be a research project not a
       | startup. If they already have a product what do they need the
       | funding for? I mean, they already know if it works or not.
        
         | TulliusCicero wrote:
         | Running clinical trials is expensive, I imagine.
         | 
         | The article says they've only done testing in animals so far.
        
         | david-gpu wrote:
         | There is a huge cost associated with moving from a proof of
         | concept to a commercially viable product. People often severely
         | underestimate the effort involved in this.
        
       | sharpshadow wrote:
       | I'm very confident that if you could sell your blood on the free
       | market and avoid donation scamming centers, which literally are
       | taking your blood for free (time compensation) and sell it,
       | partly to the Pharma industry for profit, the problem of not
       | enough blood would be solved quickly.
       | 
       | But blood counts as organs and organ trade is prohibited.
        
         | spuz wrote:
         | Actually, selling blood is legal in the US under the same law
         | that legalises selling plasma. But hospitals won't use sold
         | blood to inject into patients because even if it goes through
         | testing for diseases, they consider it too high a risk.
         | 
         | https://www.statnews.com/2016/01/22/paid-plasma-not-blood/
        
           | sharpshadow wrote:
           | Ohh that's good to know thanks. Here in Germany and probably
           | Europe it's not allowed not even the plasma part.
        
       | sharpshadow wrote:
       | "An earlier class of candidate blood substitutes tried to replace
       | hemoglobin with oxygen-bearing chemicals called
       | perfluorocarbons..."
       | 
       | Great idea back then in the 80s the forever blood.
        
       | gglon wrote:
       | How does it compare with xenotransfusion from genetically
       | modified pigs?
       | 
       | https://en.wikipedia.org/wiki/Xenotransfusion#Ethical_argume...
       | 
       | I guess the extended shelf life and more compatibility might be
       | some of the pros of synthetic blood.
        
         | odyssey7 wrote:
         | In terms of logistics, you wouldn't need to raise genetically
         | modified pigs. You could potentially scale production on demand
         | and it doesn't require the environmental footprint of
         | livestock.
        
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