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Growing New Cartilage
bsletten writes "Researchers at the Duke University Medical Center have successfully grown fat cells into cartilage, that they hope to use to repair/create new joints for patients. Normal cartilage does not repair itself well so this should be a boon to people with knee and hip problems." Cartilage doesn't repair at all, and there aren't any good replacements for it. I think teflon disks are the state of the art now, and they wear out eventually, which necessitates more surgery. Creating real cartilage replacements would be a major advance.
Mesenchymal Stem Cells (MSCs) can be isolated from bone marrow, are easily expanded outside of the body, and can be converted into a variety of tissues, including fat cells, muscle cells, bone cells and cartilage cells. Unlike adipocytes (fat cells), they are easier to grow, easier to isolate, less delicate and more naturally converted into cartlidge cells.
A company, Osiris is working on developing technology around these cells.
There is also a Science paper on these cells.
Full Disclosure: I work with these cells, and can routinely convert them into fat, bone and cartilige cells.
A lot of children died in childbirth and of diseases in the first few years of life. In young adulthood you were at risk of dying either during hunting or war if you were male or in childbirth if you were female. If you lived beyond that you quite often lived to 60-80 years, ie a modern lifespan.
You're correct that there is no evolutionary pressure to develop repair of cartilage though, because evolution doesn't care about you much once you breed. Once you're beyond 35 there isn't a lot of breeding or fighting left in you, so you're not an evolutionary priority. Sure, maybe you serve an elder role, so there's some competitive advantage there. But you'll probably pass all that wisdom on by age 60 or so in a hunter-gatherer society anyway. More likely our survival beyond age 35 or so is just an evolutionary appendix.
Uh, you gotta read the article closer.
I don't have the ORS abstract on hand (I've been out of the cartilage research business for a couple years now) but even the spoon-fed Reuters wire feed mentions that the researcher (Guilak) doesn't have a clue whether he's actually using adipose (fat) cells or other stroma cells.
Whether they're adipose cells or stroma cells, if you separate them out of the body and put them on a culture plate, you tend to get cells which look a lot like fibroblasts. When you put fibroblasts into a three dimension matrix (the article doesn't mention which one, probably alginate or collagen-gag scaffolding) they tend to assume chondrocytic (cartilage) like properties. This is absolutely nothing new, except that Guilak's getting these fibroblasts from fat tissue rather than any other tissue in the body (fibroblasts are everywhere).
The real question is whether the chondrocytes are producing type II collagen (i.e. what you find in articulating surfaces like your knee joint) or type I (which is most of the collagen in your body, but completely unsuited for making knee joints). I doubt his cells are making significant levels of type II collagen. Even if they were, seeding cells into a matrix and getting type II collagen expression is nothing new, this has been done for years by various different groups (Ragan/Grodzinky at MIT, Koichi Matsuda (sp?) at Chicago/Rush, etc.).
Even if you're getting type II collagen formation, you also got to hope that the collagen is being assembled and oriented correctly so that it won't fall apart after a couple years, and I know of no current evidence that explains how this can be done outside of a developing body.
Sorry, this isn't a huge advance. This is just someone (Guilak?) trying to make news out of nothing.
The field of cartilage research is advancing greatly, and quite likely in another 5-10 years people will be able to recreate functional articular cartilage in an ex-vivo system. But there's still a lot more work to be done, and you're more likely to get the cells from a quick mouth swab than liposuction anyway.
This is a HUGE advancement! Not onlly do they have a way to "maufacture" cartilage, they are NOT doing it from embryonic stem cells! Stem cell research is much more advanced in Europe, and they actually have some cartilidge therapy based on stem cell research and injections; but the fact that this team has been able to do it with Adult Fat cells is mind breaking! This is of particular interest to me as I am one of thousands of people (probably millions) who have damaged there cartilage. I was in a car vs. rollerblade accident almost exactly a year ago and "shattered" the cartilage in both of my knees; in the US as stem cell research is so contriversial, my Drs said that there was little I could do, but hope it got better and look forward to knee replacements. (which they can only do twice btw and only last ~15-20 years; I am 20) While this is still very early in the research/test stage the idea that I may be able to run again is so exciting I don't have words for it!
-OctaneZ
Have you ever considered what the average life span was up until several thousand years ago? If you don't live past 30 your cartilage won't wear out...so there is no evolutionary pressure to waste resources on repair mechanisms.
You have to wonder how far how quick are we really going in terms of bio-engineered replacement parts for humans out there with real problems. Cartillage would be really great. A new major organ like a kidney for my really cool brother-in-law would be even better.
However, the real deal is when will the gee-whiz first break throughs eventually turn into real world results and are the projects being funded appropriately?
Those are questions that beg to be answered for the people living the problems.
I don't want to put down the results of the first real progress being shown in the field. I just sadly wonder how long will it take to start saving lives and is society as a whole supporting these efforts with enough resources?
ACK
This is a wonderful breakthrough, and will be useful to athletes, those with degenerative bone disease and the aged.
Unfortunately, however, I feel there is a predisposition in the medical research industry to focus on those diseases which the aging, affluent baby boomers will contract; baldness, impotence, type II diabetes, heart problems, osteoporosis, etc.
I hope they also move their focus closer to diseases that prevent people in less developed countries from reaching the age at which many of these diseases develop.
AIDS, trachoma, hepatitis, typhoid, cholera, yellow fever, malaria, and tuberculosis still rage. With climactic change and increased travel, they will continue to spread.
A balanced priority schedule in medical research takes these important social and ecological factors into account.
Goat sex free since 2001
Because of claims that shark cartilage is an effective treatment for joint problems, millions of sharks are killed each year in order to make cartilage supplements. Despite no scientific evidence to support these claims or other claims that shark supplements treat cancer, this chondroitic genocide persists.
Maybe now we can concentrate on growing our own cartilage instead of killing other animals for theirs. Everyone wins.
Read the rest of this comment...
Okay, I've actually worked in the Vacanti Tissue Engineering laboratory, the lab that did the Ear-on-the-back-of-the-mouse experiment. I've since moved on doing other work on stem cells.
Cartilage usually doesn't repair appreciably on its own because it is one of the least densely populated tissues in the body. Cartilage is mostly extracellular matrix (ECM) proteins like collagen with a few cells scattered here and there to put out enough protein to maintain the tissue structure. It's also very poorly fed as few blood vessels travel through the cartilage so the few cartilage cells (chondrocytes) present operate at a slow metabolic pace too.
Cartilage has been an early and popular target of tissue engineering efforts. First of all it's a relatively homogenous, simple tissue. Secondly, alot of people have problems with damaged cartilage. What's done is that a porous 'scaffolding' of some material which will break down in the body is molded into the desired shape and then cells are 'seeded' onto the scaffolding with the intention that they will colonize it and grow. The breakdown characteristics are matched as closely as possible to the ECM buildup of proteins released by the cells. Eventually the artificial scaffolding is replaced by tissue. That's what the 'ear' on the back of the mouse is (by implanting it in a mouse, the engineered tissue gets fed in an 'in vivo' environment). Tissue engineered this way has yet to match the physical properties of normally produced cartilage, but there are approaches being investigated to improve these characteristics such as growing the tissue under a physical stress load.
The limiting reagent in this process is the supply of cells for seeding. That's why this story is news. During development, cells take cues from their environment and long range chemical signals to decide where they are and consequently what cell type would be apporpriate to differentiate into. However, not all of the cells in the body move into a final specific cell type. Some of them remain generalized as a pool or reserve of cells. Bone marrow is the easiest example of this. That's what has been taken advantage of here. The chondrocytes in this experiment were developed from stromal cells (not fat cells like the headline states). These are a less specific cell type than either chondrocytes or fat cells (adipocytes). They were grown in a physical environment and fed chemical signals that 'convinced' the cells they needed to become chondrocytes. Figuring out these conditions and signals is a nice piece of work.
There are quite a few pieces of research like this coming to light in the last two years. The direction of research in the stem cell field is moving towards trying to turn 'stem' cells from one particular tissue into developed cells of another tissue. Some labs are even trying to take fully differentiated and presumably committed cells and get them to turn into other cell types, sometimes referred to as 'trans-differentiation'. In that regard, this research isn't earth shattering, it's one more piece of confirmation. Also, if trans-differentiation is confirmed as a general trend, then you could conceivably get chondrocytes from many many different tissues in the body.
As a source for engineered tissue though, this has the practical advantage of being from a readily available source. Nicely done.
Did anybody else read this as if it implied that the researchers at Duke ate a few too many burritos from Taco Bell?
Cartilage doesn't repair at all, and there aren't any good replacements for it
Actually, that's not true. Everybody who gambles in "fantasy football" leagues know that you can replace cartilage with... (drum roll)... cartilage. Several NFL wide receivers have had knee cartilage replacement (using cartilage from donor corpses), and have gone right back to sprinting past cornerbacks. So the best option to date has been cartilage from people who checked that "donor" box in their driver's licenses and then failed to wear a seatbelt.
Growing cartilage from fat cells is good news. It will probably make replacement parts cheaper and easier to get, so you won't need to be a millionaire athlete in order to afford getting your knee fixed.
Information wants to be anthropomorphized.
This is not an entirely new approach to repairing damaged cartiledge. It appears that the only thing new about it is that they are cloning one type of tissue into a *different* type of tissue. Cartilaginous replacements are being done in other ways...
In December I underwent knee surgery to remove a piece of bone about the size of a quarter that had broken off from one of the inner surfaces of my knee. At the same time a cartiledge biopsy was taken (i.e., a small sample of tissue) which will be cloned into a piece of replacement cartiledge which will be reimplanted in my knee if enough scar cartiledge doesn't form where they drilled a bunch of tiny holes in the end of the bone (yes, it was even more painful than it sounds for about two weeks following the surgery) to stimulate scar cartiledge growth where the chunk of bone was removed from where it had been mangling the cartiledge in my knee.
My doctor might be irked with me for getting them Slashdotted this way, then again they might not mind the exposure, but here's a URL for the type of surgery I went through, and more specific details on the why and the how of the cloning of replacement cartiledge.
http://www.iasm.com/ccc.html
Where in the hell did you get your science education? From the back of a Cap'n Crunch box?
"Evolution" is completely biological. It says nothing about the formation of the universe, galaxies, planets, or anything other than biological entities. Don't listen to Creationists who use the term "evolution" to refer to any piece of science that they believe contradicts their Bible. If you want to study the formation of the universe, check out cosmology. If you want to study the formation of the planet, check out geology. If you want to study the progression of life forms, check out biology (and biological evolution.)
The "special theory of evolution" states that two similar life forms that are in inertial Galilean reference frames in rectalinear motion relative to each other will evolve in roughly similar fashions. The "general theory of evolution" takes this one step further by positing that two similar life forms in any two reference frames will evolve in a roughly similar fashion, regardless of motion, direction, or acceleration. The presence of mass and radioactivity creates a curvature in the gene pool that makes genetic mutations far more likely.
Get your science from science books, not from Jerry Falwell. Thanks.