Making Bone With An Ink Jet Printer. Well...Bone-ish.

Reading the headline, "Engineers Pioneer Use of 3D Printer To Create New Bones" from the BBC I can't help but imagine your standard ink jet spitting out layers of human bone until you come up with a whole femur. In case you aren't familiar with 3D cell printing, let me be the one to tell you that isn't the case. I think the BBC's headline leaves out a crucial piece of information: what the printer in question creates is a scaffold of bone-like material.

The research in the article was conducted at Washington State University, and I find their PR headline "3D Printer Used To Make Bone-like Material" more specific. I think 3D printing, tinkering with a printer so that it can make different kinds of biomaterials, is interesting in its own right. I'm okay with the fact that the material being made is only bone-ish and not really bone. Although and argument could be made for the BBC's headline... which I'll explain later.

Printing the bone scaffold via WSU

Here is the research rundown: led by Susmita Bose, professor of mechanical and materials engineering, WSU researchers used a 3D printer to to create a scaffold of calcium phosphate, silicon and zinc. When paired with actual bone, this scaffold provides a structure for new bone to grow on, to specifically manufacture the desired bone. The scaffold dissolves with no reported adverse effects, according to the researchers' in vitro tests in rats and rabbits.

Described in the journal Dental Materials, (according to the PR*) the printer works by having the inkjet spray a plastic binder over a layer of the calcium phosphate, silicon and zinc powder in very thin layers (about 20 microns, comparable to the width of a human hair). A computer directs the printer to create the scaffold in the desired shape and size. The researchers found that after a week in a medium containing immature human bone cells, the scaffold was able to support new bone cell growth. According to the researchers, the material is likely most suitable for low load bearing (so, not a femur) and could be available for human use in a few years time.

So back to the BBC's headline about the 3D printer creating new bone. Ultimately, that is what happens. New bone is grown around the scaffold, so the end product is real human bone. However, the printer is not itself printing bone. In my humble opinion, that doesn't make this research any less cool. While the BBC's headline wasn't itself inaccurate, I think it leaves a lot of wiggle room for assumptions (or at least imaginations like mine getting carried away with themselves) and accuracy is the end all and be all of science stories, isn't it? Something like "3D Printer Creates Scaffold For New Bone Growth" isn't as pretty as either headline used, but I think it would get to the heart of what this story is a little bit better.

For more information about the technology check out this video from WSU's press page:

*I am typically loathe to post about a paper that I haven't at least looked at the abstract, but I cannot find this paper online anywhere. If someone has a link, that would be awesome. 

Humans Contaminate DNA Databases

Interesting research has been published in the online journal PLoS One, describing a problem with contamination in non-human DNA databases. DNA databases are libraries of genetic information about specific species. When a species has its genome sequenced, its genetic data goes into a database so that other research can be conducted based on that known genetic information.

When a DNA database becomes contaminated it means that there is other information that has corrupted the data stored in the database. In the new PLoS One paper the researchers (from the University of Connecticut) evaluated human contamination of databases that were supposed to contain other species - like the zebrafish. So contamination occurs when human DNA gets incorporated into the database for another species. When researchers go to work with the data about the zebrafish for example, they are actually working with human data without knowing it.

The University of Connecticut researchers looked for human contamination in NCBI genome databases, the University of California Santa Cruz (UCSC) databases, and the Joint Genome Institute databases. They found human DNA where it shouldn't have been in a total of 492 of 2,749 evaluated databases.

This contamination issue is extremely problematic because research conducted based on contaminated information can not be trusted to be accurate. It can also be very difficult to track down which databases are contaminated unless the resources (time, money, etc) are spent to evaluate databases for clarity - as was done in this new research.

Database contamination is a relatively new issue brought to light be the massive influx of new genetic information made possible by improved genome sequencing technology. A similar issue that has existed for decades is cell line contamination which occurs when cells that are suspended in culture (alive outside of the body) are contaminated with cells that aren't supposed to be there.

No regulatory body has stepped up and put a stop to cell line contamination in the last thirty years. I just hope that database contamination doesn't follow suit.

To learn more, read the paper about Database contamination, or read an article I wrote for BioTechniques about cell line contamination. As taxpayers we spend a lot of money to fund scientific research, so it is important to know what problems (like contamination) exist in the research community.

Food Printing

Whenever I think about the food of the future, I think about Star Trek (I know, I know... I'm a nerd in a sorority girl shell) and how in the show their food is created by a machine that assembles the molecular composition of whatever food you order right in front of you. Needless to say like my hover car and robot maid, such things are still far in the future, but an interesting new way to prepare food is channeling this type of future food.

Food printing is a new technology that follows a recipe all on its own to come up with different meals, all you need to input are the ingredients. The technology is being developed by a team of researchers at Cornell University's Computations Synthesis Lab as part of the Fab@home project. The 3D food printer only requires users to put in the ingredients and program the recipe, and the machine will do the rest. It can even be adjusted for picky eaters -- making food moister or crispier, depending on the tastes of the consumer.

The technology would be especially beneficial for people won't don't either know how to cook or who don't have the time to prepare big meals. It could also cut down on costs by limiting production waste during food preparation.

I'm pretty amazed by the creativity that researchers have shown in utilizing printing technology for new applications. In addition to 3D food assembly, printers can also be used for 3D cell culture. I wrote and article about 3D cell printers for BioTechniques last year, and I was amazed by the machines' capabilities.

The Immortal Life of Rebecca Skloot

Today I met Rebecca Skloot, the author of The Immortal Life of Henrietta Lacks, mentioned in my previous blog post. Skloot's book is the UW Madison Go Big Read program's selection for this year, so she gave a public lecture last night, and visited the journalism school this morning to take questions.

As far as author presentations go, I loved this one, because Skloot pretty much just plopped down in a chair and said what do you want to know? It was a small group (25-30 people) but the discussion kept up for over an hour just based on audience questions. My question for her was whether she was prepared for the Lacks family's lack of science education and how she viewed her role as a journalist but also as their teacher. Her response was that the two roles were essentially one because her reporting style is based around an informal conversation, but that she wasn't really prepared for how confused they were about what HeLa is.

Other questions that were asked ran the gamut from the business of publishing a book, to how Skloot handled Deborah's death and incorporated it into the book, how she decided on the structure of the book, and how she handled (and organized) 10 years worth of notes. She was an engaging speaker, and was even willing to talk about some of the criticisms of her that have come up since the book came out.

The biggest criticism of Skloot out there is that she isn't doing enough to help the Lacks family. But, she has set up a foundation for them -- and I think its important to remember that for 10 years Skloot was accumulating debt chasing down this story, if the book hadn't been a success she'd definitely be in the hole so I agree with her unapologetic attitude toward the money she's made from the book's success.

She also mentioned that she sometimes gets push back from people who don't agree with the fact that she kept all of the interviews in their original dialect (people saying it puts down the lesser educated black people who don't speak with proper grammar) but Skloot points out that she kept the dialect and "broken" English of European and Asian researchers as well as the Lacks family.

According to Skloot the biggest problem she's encountered so far has been from the white members of the Lacks family. In the whole two pages that the white Lackses are discussed, they definitely appear as racists. But, it is Skloot's word against the word of the children of her sources (her sources are now dead) who have argued that Skloot couldn't possibly have done the interviews because their parents wouldn't have said the things Skloot says they did.

Considering how utterly unimportant the white Lacks family is to the story, it's sort of absurd to think that Skloot didn't really do the reporting. It would be such a dumb part of the story to make up, so I'm inclined to believe that the interviews are true.

This book is undoubtedly going to be Skloot's literary legacy, so overall it was fun to get another first hand perspective on what it takes to research, write, and market a successful science book.

Cell Culture's Dirty Little Secret

My last assignment for BioTechniques web news was a cell culture themed newsletter article on the status of cell line contamination. It was while researching that article (Ending cell line contamination by cutting off researchers) that I got my first real education about HeLa cells. I recently added to that education by reading Rebecca Skloot's The Immortal Life of Henrietta Lacks for J669.

I already had a firm grasp on the science of cell culture and contamination of cell lines, but the book gave me a lot of background about Henrietta Lacks, the woman the HeLa cell line was harvested from (and thus named after). Cell line contamination is the dirty little secret of the biological research community, and the story of the Lacks family certainly doesn't make the research community look any better.

HeLa Cells. Source: Wikimedia Commons.

One thing that I like about Skloot's book is that she doesn't look at either the family or the researchers involved in the HeLa controversy with rose colored glasses. I think the book is fair because it drives home the point that the researchers involved in cell culture in the 1950's all followed protocol at the time. There isn't a single person to blame for the fact that Henrietta Lacks' cells were cultured without her consent or that no one ever bothered to educate her family about cells, what it means to grow them in culture, and the research that cell culture enables.

It wasn't standard practice back then to tell research subjects much of anything. Not that I think what happened to the Lacks family is ok, I believe in informed consent - even if that means giving someone the basic science education they need to understand what will happen to their tissues once they give them up to science. But, hopefully publicizing more stories like the Lacks family's will help people speak up and learn more about biological research.

I found Skloot's book compelling, but my biggest problem with it was the ending. To me, it just ends abruptly. The death of Lack's daughter Deborah (who is a major character in the book through her interactions with Skloot) gives the book an ending of sorts, but something is still missing. I wish that there was something that could tie the book together like a change in policy or new regulations put in place, but sadly no such changes have occurred.

Cell line contamination is a rampant problem in the biological research community, and currently in the United States there are no regulations that force researchers to verify the origin of their cells lines or identify the contaminants they may have been exposed to. Cell line contamination pisses me off. We spend billions of tax dollars on research -- that may end up completely worthless because researchers have no incentive to check and make sure that the cells they are working with are what they think they are. What good is research for treatments for blindness when you aren't working with corneal cells, you are actually working with cervical cancer cells?

If you want to learn more about cell line contamination, a search in PubMed (a database of academic research papers) for Roland Nardone will yield several academic papers on the issue, but I suggest reading "Recommendation of short tandem repeat profiling for authenticating human cell lines, stem cells, and tissues," because it actually offers a solution to the problem of how to authenticate cells.

Science Writing Highlights

For the last year (2009-2010) I've been writing for the journal BioTechniques. In that time I've written way to many articles to post here, but here are a few favorites from Spring/Summer 2010:

"Ending cell line contamination by cutting off researchers" is my most recent piece, about how the biological research community can end the widespread use of contaminated cell lines for published (and peer reviewed) research. New York Times bestselling author Rebecca Skloot (who literally wrote the book on HeLa cell contamination) posted a link to the article on her Twitter.

"Fastest case of adaptation documented in Tibetans" reported on (what I think is) a really interesting development in the study of human genetic adaptation to environmental conditions. Basically, Tibetans adapted rapidly from Han Chinese to thrive in low-oxygen environments.

"The sequencing race: the home stretch" was a follow up to an article that I wrote that appeared in the February 2010 print edition of BioTechniques. The whole suite of articles reports of the progress that has been made (and is anticipated) in the field of genome sequencing technologies.

"Plant biology blasts off: shuttle missions explore biofuels" reported on experiments featured on the last few NASA shuttle missions exploring the affects of zero-gravity on possible new biofuels.

"Facial expressions quantify pain in lab mice" is about a method to quantify whether or not laboratory mice are experiencing pain due to their role in an experiment based on the way the features of their face change, indicating pain. It raised some important issues about animal rights, specifically what constitutes suffering and whether the animals are aware of what is happening to them.