Posts Tagged ‘stem cells’

The Human Cloning Thing

May 18, 2013

Chances are at some point you’re going to die. As for how that may happen, most people don’t know.

Some people have an idea of maybe how their time will come. Maybe they have heart problems, or immune-deficiency, or lung problems, or a failing liver, or some dreaded disease or whatever.

If you know, for instance that you’ve got a weak liver, then perhaps you have a feeling that it will be liver failure that will do you in. Maybe you know this because you have drank too much beer over the years, or maybe other life choices you have made have placed the good condition of your liver at risk. Or maybe you were just born with a liver that is weaker than most.

Each one of us will have our own particular life-threatening set of body-failure probabilities to deal with.

So maybe, when your time draweth nigh, you will want to call upon the medical profession to bail you out of the inevitable deathly situation; you may seek the doc’s help in extending your time on earth.

Maybe you would, for instance, want to get a liver transplant so that you can live longer, or a heart transplant if  that’s what the issue is, or some brand-new, cancer-free bone marrow so you don’t die of leukemia, if that is your problem.

If the weak link in your bodily chain of organs is, let’s say, your liver, perhaps the doctor would say that you could be a candidate for a liver transplant. Or if your heart  has some defect, then the transplant would we be a new heart.

Now the problem with that medical remedy is that your body may reject the liver, or heart, that has been grown in someone else’s (the donor’s) body. And I think this complication arises mainly from the reality that the donor’s DNA makes their liver uniquely equipped, on a cellular level, for that person’s body, not your body. The doctors, if they are going to insert someone else’s liver in your body, need to all sorts of pharma tricks with baling wire and duct tape just to get the transplanted organ to “take” inside your gut.

Think of it like a car. Maybe your old chevy needs a new fuel pump. No problem. Just mozy on down to the dealership and pickup a new fuel pump. But of course you can’t just buy any old fuel pump. It has to be the one that was made for your particular impala or chevelle or whatever chevy model you have.  Or Fiesta or Fairlane or Focus if you’re a Ford guy. And even more specific than that, the new part has to be selected according to the year in which your car was manufactured.

Same thing for your liver. Your very own, personal DNA-delivered liver has been humming right along all these years because it has the same genetic identity as every other cell in your body. You’ve been cruisin with a custom job all these years and maybe didn’t even realize it, because it looks so much like the mass-produced version.  But now, if your liver is worn-out, you’re looking for a replacement. But the replacement for your old ’57 chevy liver will not be found in the body of some accident victim 2011 Volt or Caprice.

So what if you could get your very own, personal DNA-delivered liver, manufactured especially for your you?

That’s what this human cloning is mostly all about: generating, under laboratory conditions, organs and regenerative cells to help your body live longer. If you’ve got the money, honey, the labs will have the time, and the technology, and the treatment– custom-tailored for you in a petri dish somewhere in Baltimore or Boston, Baton Rouge, Bakersfield or Bellevue.

This is called therapeutic cloning, not reproductive cloning. These are two different basic cloning objectives, although I think the procedures are very similar in the very earliest phases of the nuclear transfer process. The objective for therapeutic cloning is, according to my layman’s understanding of it, to generate patient-compatible pluripotent stem cells that can be used to grow new healthy tissue in the recipient’s body.

Now the researchers who have been working on and/or monitoring these research developments are for the most part, I think, agreed that reproductive cloning is not a good idea; some would even perhaps use the word “immoral,” or “ethically inappropriate,” or some such euphemism as that.

But this is a brand new can of worms that the scientific community, the medical community, and the general public will be dealing with as the years roll by and budgets are written while dollars are spent and the people come and go talking of michelangelo or donatello or mutant ninja turtles or chimerae or whatever. And everyone will make their own decisions about such things based on their own info base, financial base and moral compass and so forth and so on.

With this announcement, last week, of a successful human embryo being cloned in Oregon, the “cat” is, so to speak, out of bag. We’re in a brave, new world, just as Aldous Huxley anticipated many years ago.

Uncharted territory.

And though the scientific community may generally have the best intentions to regulate cloning procedures and outcomes to direct them within  channels of therapeutic application, we all know how the human race is, and what will probably happen.

Not only is the cat out of the bag, but pandora has opened her box, and sooner or later some renegade Dr. Frankenhoo will do the reproductive thing and then he won’t be able to resist letting all the world know and everybody will gasp when the first human clone shows up in a playground somewhere in Beijing or Ankara or Brussels or LA or Godonlyknows where.

And there will be prosperous folks who want to clone themselves and they will have the money to have it done and it will happen. Welcome to our 21st-century can of ethically-challenged worms. Will all our human-carnival predisposition for vanities and manipulations and exploitation and avarice and under-the-table dealings, back-alley abortofreaks, black-market, after-market, post-market, postpartum proclivities just take a back seat to the benefits of having therapeutic-cloned body parts?

Probably not, but then again maybe. Whatever beneficial things can happen will most likely be duplicated by somebody. You know how copies are; their quality depends on the equipment you use. So anything can happen and most likely will. Copy this message to someone if you think about it.

Glass Chimera

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The two types of stem cells

June 18, 2011

A couple of years ago, I delved into a personal research project,  in order to write my second novel,  Glass Chimera. From a layman’s perspective, I was learning about  genes, DNA, cloning, and other areas of scientific endeavor that pertain to the science of genetics.  I learned a lot about the human genome, more than I can ever understand or explain.

One particular area of genetics that is often discussed in our era is  the use of stem cells. My limited investigation into the subject has brought me to this observation about stem cells: there are basically two types of them.

Embryonic stem cells are those found in the fertilized egg, or the embryo, of a newly-conceived fetus in a female’s uterus. These are the controversial stem cells, because the harvesting of them for medical use will most likely alter or terminate the embryo’s fetal development.  Embryonic stems cells are pluripotent, insofar as they have potential to differentiate into many types of cells that are necessary for a fully developed body to, after birth, sustain life. These cells can be directed by the DNA genetic code to become, for instance,  blood cells,  skin cells,  muscle,  nerve, or whatever cells. My limited studies have  indicated that the  main value of embryonic stem cells is found in their use for medical research.

In the novel that I wrote while studying this, I include a hypothetical conversation between two graduate students in microbiology. In chapter 24, Erik is explaining  stem cells to his friend Sam:

 “. . .these guys that are doing this type of work, they remove the stem cells from the ICM (inner cell mass) that has congregated inside the 5-or-6-day old blastocyst—“

“So they’re sacrificing the embryo?” Sam wondered.

“I guess you could call it that,”

“What do they do with the outer part?”

“Oh, the trophoblast, God only knows.  I suppose they use it for something or other in the lab, or maybe they culture those cells for some other developmental purpose. I don’t know.  Anyway,  they place the totipotent stem cells into culture and propogate them.”

“That’s what we call a stem cell line,” observed Sam.

“Uhhuh, but it’s tricky.  Those cells have a built-in tendency toward differentiation.  If they’re kept alive unto themselves, without chemical restraints, they’ll start to organize themselves into an embryo again.”

This “differentiation” potential of stem cells is their most useful attribute. At the same time, it is the very thing that makes them somewhat dangerous.

I mentioned above that there is another  type of stem cells: adult stem cell.  Their differentiation potential is quite limited, as compared to the embryonic type, but they are much safer for medical applications, mainly because they are obtained from a patient’s body, and then injected back into that same patient. So there’s no conflict between the genetic info in the medically modified stem cells and the genetic data resident in that patient’s other billions of cells.  This second type of stem cell, the “adult” type, exists in the body of every child and adult. They enable the growth of new bodily tissue, and they exist in every part of the body.

Yesterday, June 17 2011, I was fascinated as I listened to a very informative discussion  on the radio about new medical treatments  utilizing these adult stem cells to repair damaged tissue.

Ira Flatow was again demonstrating his customary excellence in science journalism. The depth and scope of  his NPR reporting  keeps  his show, Science Friday, on the cutting edge of popular science education. I always obtain galactical levels of new information and insight when I can listen to his Friday program, or catch it later online.

The spot I heard yesterday was SciFri 061711 Hour 1: Black Holes, Untested Cell Therapies, Solar Update, which I had clicked on at

http://www.sciencefriday.com/about/listen.

 

Ira was speaking to two medical doctors about Bartolo Colon, the great NY Yankees pitcher whose injured pitching arm required medical treatment. Ira explained that since the pitcher was in the latter years of his baseball career, surgery to correct his elbow problem might be too risky. So Bartolo had elected to have this relatively untested therapy performed on his arm by doctors  in Dominican Republic.  And guess what, it worked! Bartholo has made an impressive comeback in his pitching career, at the age of 37.

Dr. Rick Lehman, an orthopedic surgeon at the US  Center for Sports Medicine (in St. Louis), described how cells taken from Bartolo’s own body had been medically treated and then injected back into his injured shoulder and elbow. The immature stem cells, as the doc explained, act to recruit blood  supply, enhance healing of ligaments, and improve the natural healing mechanics inside the patient’s body.

Dr. Scott Rodeo, orthopedic surgeon at the Hospital for Special Surgery (in New York City) contributed to their fleshing out of the subject with specific comments about Bartolo Colon’s surgery, but also with some interesting facts about the different kinds of stem cells.  For instance, risk of cancer is far lower with the use of these adult stem cells than the risk from using  more primitive stem cells, such as those pluripotent ones found in embryos.

As a writer whose research had skirted these areas pioneering medicine, I was fortunate to have heard their productive talk on NPR about the  minimally surgical restoration of a great pitcher’s arm.

And congratulations to Bartolo Colon, whose baseball career has been renewed.

Glass Chimera