New Microscope Reveals Ultrastructure of Cells

An anonymous reader writes "For the first time, there is no need to chemically fix, stain or cut cells in order to study them. Instead, whole living cells are fast-frozen and studied in their natural environment. The new method delivers an immediate 3-D image, thereby closing a gap between conventional microscopic techniques. The new microscope delivers a high-resolution 3-D image of the entire cell in one step. This is an advantage over electron microscopy, in which a 3-D image is assembled out of many thin sections. This can take up to weeks for just one cell. Also, the cell need not be labeled with dyes, unlike in fluorescence microscopy, where only the labeled structures become visible. The new X-ray microscope instead exploits the natural contrast between organic material and water to form an image of all cell structures. Dr. Gerd Schneider and his microscopy team at the Institute for Soft Matter and Functional Materials have published their development in Nature Methods (abstract)."

Comments

Lemme guess.. the article has no pictures

[mozumder]

(checks article)

yep.

Re:Lemme guess.. the article has no pictures

[Anonymous Coward]

there are several pics from the article here:

http://www.nature.com/nmeth/journal/vaop/ncurrent/fig_tab/nmeth.1533_ft.html

Re:Lemme guess.. the article has no pictures

[Snowgen]

Call me a Karma-Whore, but here's the clickable link: http://www.nature.com/nmeth/journal/vaop/ncurrent/fig_tab/nmeth.1533_ft.html

Re:I never thought I'd say this here

[MeanMF]

There are pictures, but unfortunately they're actual size.

Where's the real article?

[AdamHaun]

Okay, I read the press release copied and pasted onto a random blog. Is there a real article with pictures we could look at?

Re:Where's the real article?

[Rashdot]

It seems that the images are accessible. Found these via Google:

http://www.nature.com/nmeth/journal/vaop/ncurrent/fig_tab/nmeth.1533_F2.html

Group website.

[gyroidben]

Didn't find any relevant pics but if anyone's interested the research group's webpage is http://www.helmholtz-berlin.de/forschung/grossgeraete/mikroskopie/index_en.html.

Re:Picture is worth 1000 words

[Anonymous Coward]

Maybe they're just respecting the copyright of the cells.

natural environment?

[jc42]

... whole living cells are fast-frozen and studied in their natural environment.

Um, unless we're talking about species native to Antarctica, I wouldn't think that frozen would be their "natural environment".

Freezing is known (and not just by the State of California ;-) to do damage to many cell structures. For example, they no longer qualify as "living".

Somehow, I think this could have been better expressed with different words.

Re:natural environment?

[interkin3tic]

Natural environment meaning microenvironment, or rather, with other cells.

A lot of cell biology is done on cells which have been mechanically or chemically separated, or cells grown in a single layer on a dish. That's okay for some studies, but if you want to study, for example, the stem cells of the intenstine, that's not much good. When you dissociate cells, they change shape which makes some of the microscopy you'd want to do on them pointless right off, and many if not most cells will start changing in other ways when you dissociate them. For many cells, being attached to other cells is a sign they're doing what they're supposed to, if they lose contact they'll start to kill themselves. It's a safeguard against metastasis of cancer cells. If you were looking at cells you isolated from the intestine after you'd dissociated them, you wouldn't be studying intestinal stem cells anymore, you'd be studying cells that were starting to commit suicide.

By freezing it and then leaving the tissue intact, you'd be able to study those cells as they are supposed to exist: attached to other cells and not undergoing apoptosis (assuming you did it right). There are ways of freezing tissues to prevent the formation of damaging ice crystals. They won't be alive, but they'll make a good snapshot.

Old technique

[vlm]

Terrible misleading article. Maybe its the first time the journalist heard about it, but its hardly the first time this has ever been done.

Despite a desperate attempt by the journalist filter to avoid "science-y words" I've figured out the technique they're talking about is xray microtomography. Basically yet another tomography tech (make a 3 d model in a computer out of a crapload of 2 d pix and lots of processing and memory) but applied to little things.

"The first X-ray microtomography system was conceived and built by Jim Elliott in the early 1980s" Back then 50 nm was considered pretty good resolution, and thirty years later these dudes are down to 30 nm. A slight improvement on the past, and it is cool, but its not like they are "the first", like being the first men to step onto the moons surface or something.

http://en.wikipedia.org/wiki/X-ray_microtomography

Saying these guys are the first, is kind of like saying I'm the first human being to see the moons of jupiter thru a telescope, with the footnote that I'm defining telescope today as being home made using these exact lenses from Edmund Optics and these specific (empty) toilet paper tubes with these somewhat unique specific optical parameters, and no one has ever used that exact tech. Or I'm the first to have ever driven my car to work, while burning these specific individual hydrocarbon molecules.

Re:Old technique

[fjanss]

X-ray_microtomography is not new. What is new is :

"using partially coherent object illumination instead of previously used quasi-incoherent illumination"

which led to :

"We obtained three-dimensional reconstructions of mouse adenocarcinoma cells at ~36-nm (Rayleigh) and ~70-nm (Fourier ring correlation) resolution, which allowed us to visualize the double nuclear membrane, nuclear pores, nuclear membrane channels, mitochondrial cristae and lysosomal inclusions."

Re:Old technique

[Anonymous Coward]

Coherence-based imaging (e.g. coherent diffractive imaging) is also not new. What these researchers have done is to push the envelope of what can be done by perfecting known imaging principles. They have not invented something drastically new.

But I'm not trying to downplay their achievement in saying that their work is not without precedent. Frankly the media is over-obsessed with novelty. They only want to report on things from a "first of its kind" perspective, but that's fundamentally disconnected from the way science is done. All advancements build on previous work. Truly new and different things are rare--and they typically don't make much of a splash when they are first tried because the initial work is esoteric, crude, and primitive.

What these scientists have done is really amazing. The images are fantastic and this will no doubt add to researchers' toolkit for analyzing materials in fine detail. I really wish that people could appreciate the quality of this work without it having to be exaggerated or its novelty mis-represented.

*not* immediate

[zalas]

Here's the relevant passage from the article with the juicy bits:

We acquired X-ray microscope images of these vitrified mammalian cells at tilt angles from 60 to +60 in increments of 1 at a pixel size of either 9.8 nm (25-nm zone plate objective) or 15.6 nm (40-nm zone plate objective). Exposure times for each tilt angle were 224 s. The total X-ray exposure (~109 Gy) produced negligible radiation damage, as we detected no difference in image quality between images acquired at the beginning and end of the tilt series (Supplementary Fig. 3). We processed the images using a reciprocal space algorithm11 to generate a 3D tomogram composed of cubic voxels whose side lengths were either 9.8 nm (25-nm zone plate objective) or 15.6 nm (40-nm zone plate objective).

So they took 121 x-ray images of the specimen, with each image taking 2-24 seconds, and then stitched them together using a tomography technique to obtain their 3D volume. It's certainly faster than a few weeks, but this is not what I would consider "immediate". The article also points out that poor cryopreservation led to some artifacts and that the resolution in this technique was still not as good as the TEM; not having an entire 180 degree rotation of the object led to artifacts as well:

We did not detect some structures by X-ray tomography that we detected by TEM, such as ribosomes and the double membrane of the mitochondrial cristae. These probably fall below the current resolution limit (see below). An additional limitation was the restricted tilt angle range (±60) used in these experiments. This led to poorer resolution in the z dimension, as indicated by a distortion in the 3D shape of some organelles, which appeared more cylindrical in x-z views (Fig. 3b) as well as an inability to obtain face-on views of the nuclear pores (data not shown) or follow the complete circumference of the nuclear membrane (Supplementary Fig. 5b).

Re:I never thought I'd say this here

[countertrolling]

That'll be a dollar... You can keep the points