Tuesday, January 31, 2012

Introducing the Cytometry and Antibody Technology Facility (CAT)

I can never tell if and when things like this become "official."  It's not like administrators are going to put out a letter to the University announcing such things, so I thought I'd mark the occasion with a post about it.  What is "it" you say?  For years the Flow Cytometry Facility and Fitch Monoclonal Antibody Facility have been working together in a cooperative spirit.  These efforts have mostly surrounded the creation of custom conjugated antibodies for use on our systems.  They will now be fostered more deliberately in the formation of a new facility.  And so it is with great pleasure that I announce that these two titans of technology shall become one - introducing the Cytometry and Antibody Technology Facility, CAT for short.  Now, I must admit, I'm not crazy about the name either, but give it a chance, it'll grow on you.  Just keep thinking to yourself, co-STAN-za!  Don't worry, UCFlow is not going away.  The two subcores will retain their identities and remain pretty much intact, however we'll be able to leverage each other's resources to create some interesting new services for you.


The birth of a mAb:  Two cell divisions shortly after a subclone
If you've read entries here before, then you're probably familiar with UCFlow, so let me tell you a bit about our new partners, the Fitch Monoclonal Antibody Facility.  For starters, the 'Fitch' part of the name is referring to cellular immunologist Frank W. Fitch, MD’53, SM’57, PhD’60 (University of Chicago), the Albert D. Lasker professor emeritus of pathology and the Ben May Institute, who joined Chicago’s faculty in 1957. As the institute’s third director, Fitch oversaw its growth into a collection of laboratories working in multiple areas of cancer research. A teacher and a mentor who encouraged students to think creatively while still abiding by scientific rigor, Fitch has also served as the editor in chief of the Journal of Immunology and as president of the American Association of Immunologists.  He was a pioneer of antibody technology and was the founder of the Monoclonal Antibody Facility.  Today, the facility's technical director is Ms. Carol McShan who has over 30 years of experience with tissue culture techniques, and novel monoclonal production.  A major thrust of the facility over the years has been the production of novel monoclonal antibodies.  This involves immunizing mice (or rats) with the specific antigen, screening the mice for a response, fusing the mouse's splenocytes with an immortalized fusion partner to create hybridomas, and finally subcloning and screening the hybridomas according to the end use of the antibody (flow cytometry, immunofluorescence, western blotting, etc...).  In addition to novel monoclonal production, the facility also produces high-titer antibody supernatant, purified antibodies, and fluorescently coupled antibodies.  A complete list of services can be found on their web site:  fitchantibodies.uchicago.edu.

Hollow Fiber Bioreactors, utilized to produce high titer mAb.
Before we talk about what's in store for our joined future, let's discuss why I think this makes sense.  I'm going to throw out a couple of economics terms to try and make a correlation to how things are done in the for-profit business world and then tie them back to what we're doing here.  What we're really talking about here is a transition from lateral expansion to vertical expansion (or integration).  My buddy wikipedia tells me that lateral expansion is the growth of a business enterprise through the acquisition of similar companies, in the hope of achieving economies of scale.  Think of BD purchasing Cytopeia or Accuri.  They gain scale due to the significant install base of these instruments.  In a lot of ways this is pretty typical of successful companies.  It can be a quick way to really expand your business and can lead to even greater growth.  This lateral expansion sums up the past few years of the flow cytometry facility.  We've added lots of pieces of equipment, grew our business, and expanded considerably.  All of this expansion was pretty much of the same stuff - that is, cytometers.  No, we weren't out 'buying up' other core facilities or things like that, but in our own way, we experienced a sort of lateral expansion.  But there comes a point when you've pretty much maxed out this horizontally-directed growth and you need to pivot.  So, what's the next logical step?  You guessed it; vertical integration.

Vertical expansion therefore, is the growth of a business enterprise through the acquisition of companies that produce the intermediate goods needed by the business or help market and distribute its product.  This type of vertical pipeline integration is another very common strategy employed by companies.  When BD purchased Pharmingen, that's exactly what was going on.  If you are making the reagents that will be used on your instruments, you can control the entire package and make sure everything fits together nicely.  This also works in reverse too.  I'll remind you of the acquisition of Guava (and later, Amnis) by Millipore, or Invitrogen purchasing Applied Biosystems (becoming Life Technologies) and getting the supply of hardware to complement their reagents.  This is sort of how I see the "merger" of UCFlow and the Fitch Monoclonal Facility.  We can leverage the expertise in reagent development and production from the Monoclonal Facility so that our users have affordable and efficient access to commonly used reagents and will therefore be able to do more experiments with their limited funding (cf. more recharge revenue).  Hopefully the synergy of expert reagent production and state-of-the-art technology will create a positive feedback loop for both sub-cores.

So what can you expect in the future?  Our main focus at the start will be an expansion of the current Hybridoma Bank.  Right now, the facility can produce purified antibody from 21 hybridomas including such favorites as anti-CD4 (GK1.5), anti-CD8 (2.43), the FC blocking antibody 2.4G2, anti-CD3 (2C11),  NK1.1, CD19, anti-GFP, and many more.  If we can get the hybridomas for an antibody, we can add it to our list.  The next step to this is creating a plan to quickly couple these antibodies to a wide range of fluorochromes on-demand.  We've spent some time with the Lightning Link technology from Innova Biosciences and it looks promising.  This system allows for coupling to a good range of colors in as little as 20 minutes.  We're still exploring many options, so if you have a favorite setup, let us know.  We're excited about the prospects for this new phase of growth in the facility and will keep you posted about new developments as they happen.

Tuesday, January 10, 2012

What to do with aging equipment: Upgrade or Replace? And a Mini MoFlo XDP Review.

I started writing this post specifically to follow through on a comment I made when talking about our upgrade of our aging MoFlo to the XDP platform (thanks for the reminder Carol).  But then, I started thinking about all the equipment we've held onto and decided to upgrade and asked myself, was it really worth it?  Before I answer that, let's lay out a bit of discussion on the matter, and then I'll finish up with my thoughts on our upgrade to the XDP.

When I think about equipment, I like to put things into 3 categories, namely Cutting Edge, Mid-Cycle, and End-of-life (EOL).  I take all my equipment and shuffle them into these categories and move them around every so often as needed.  This way, I can put things like service contracts, maintenance budgets, capital investment, and upgrades into perspective according to pre-determined criteria.  For example, I'll stick instruments like our 4-laser Fortessa, or ImageStreamX into our Cutting Edge category.  This means they probably won't require a huge maintenance budget since things aren't likely to break yet.  However, they may need more personnel time because the applications performed on them are likely to be complex.  I'll shuffle staff and training resources to those instruments.  Mid-Cycle equipment are things like our 4 year old LSRIIs.  Things are likely to start breaking and so they may eat up some service budget, but they are the workhorses and need to be running full-time.  The applications are probably fairly routine, so they may not require as much custom tech time.  Lastly, our EOL instruments are things like our ancient FACScan and FACSCantos, and it's these instruments on which we need to make decisions.  Depending on the maintenance of these EOL'ed instruments, they may require varying amounts of service and since they may not be as desirable to use as the cutting edge cytometers, you'll need to determine how much money you're willing to invest to keep them limping along.

These EOL instruments can be a pretty decent consumer of budget and may or may not return all of their costs from recharge.  It is with these instruments that we must decide; replace or upgrade (or I guess you could just let them die a slow death).  You'll need to first determine if there is an upgrade path for your instrument.  In the case of the MoFlo, this was a whole-hearted YES, thanks to the good folks at Propel Labs.  Other instruments where this may be a possibility include FACScans and FACSCaliburs, which can be transformed into completely new instruments courtesy of Cytek Development.  If there is not a path to upgrade, then the decision is an easy one.  However, if you're looking into an upgrade, you'll need to weigh the costs against the benefits and definitely compare it to simply purchasing a brand new instrument.  If you're going to shell out a bunch of money on an upgrade, it may make more sense to look into getting a new cytometer.  Sure, you may have to settle with something a bit less powerful, but it'll be nice and shiny and (hopefully) problem-free for a few years.

So, let's put this all into practice with a retrospective look at our decision to upgrade our MoFlo.  We had our MoFlo originally installed in 2000, and approaching 2008, it was definitely showing its age.  Many of the buttons on the "rack" had fallen off, and it seemed like a waste of money to replace entire electronic bays on a rack to simply fix a button.  In addition, parts to fix the MoFlo were somewhat scarce, and it looked like many of the components were approaching their demise.  At the time, options for a new sorter were limited to the FACSAria, the inFlux (both from BD), the Reflection (from iCyt), and the MoFlo XDP (from Beckman Coulter).  All of these instruments easily approached the $0.5Million mark, so buying a brand new sorter without an SIG or a generous donor was pretty much a long shot.  Seeing as our MoFlo was still humming along just fine we decided to look into an upgrade.  The goal going into this thought process was to have a sorter that would handle a lot of the cell line type sorts using GFP or other RFPs and perhaps a few phenotyping experiments.  We did not have the expectation that it would rival our FACSAria and start performing multicolor phenotyping sorts as well as the Aria does.  We also noted that our "GFP" sorts accounted for about 30% of all our sorts and guess what?  We had 3 sorters; a perfect match.  We were able to upgrade our MoFlo for about 1/3rd the cost of a new sorter and get a few more years of life out of it while we waited for the next big thing!

MoFlo-XDP Mini Review:

I can say that the XDP upgrade pretty much met our expectations.  It handles most of our GFP/RFP sorts just fine, and is able to do a few more sorts on markers that are relatively bright.  It by no means can resolve populations as cleanly as our Arias, but it does well enough for many things.  The single best feature of the XDP is zero coincidence aborts.  You may be thinking to yourself, well isn't the Aria marketed as having very low abort rates as well?  It is, but when i say zero aborts, I really mean zero aborts, even when you have 30,000 - 40,000 events going through per second.  The place this comes in handy are rare event sorts at high throughput rate.  We can sort very rare populations and have a really good yield when compared to our Arias. What this really means, however, is that you have absolute control over your yield.  If you need every single cell possible, you can run fast, have confidence that you'll be able to make a sort decision on every single cell, and using a yield sort mode, sort out every single cell.  Sure, it won't be very pure, but at least you have them all and can decide to resort again if you need purity.  Our specification for sorting yield is a 1% population with 70% yield using the purify sort mode (to achieve 98% purity or better).  The max event rate able achieve this on the XDP is about 30,000 eps.  The max rate able to achieve this on our Arias is slightly less (~22,000 eps).  The touch screen is a bit annoying at first, but I've gotten use to it.  The biggest problem with it is the implementation of the slider and up and down arrows.  The slide is way too sensitive, and the up and down arrows are way too slow.   This interface is used for adjusting things like frequency and amplitude and plate voltages.  The new and "improved" Sort Master, dubbed Intellisort, works intermittently for us.  It took a lot of playing around, but we can get it to hold onto a node pretty well these days, but for a while we completely ignored it.  I still think this can be done way better, and apparently Intellisort II delivers, but I'm not going to hold my breath for that one.

So, am I happy with my decision?  Absolutely!  Would I do it again today?  Not too sure. What it boils down to is, I spent a good chunk of change for a sorter that has 4 lasers and about 4 usable detectors at any given time.  The need for the 4 lasers is pretty low, so I could get by with a 2-laser 4-color sorter and be able to do everything I'm currently doing on my 4-laser 10-color MoFlo-XDP.  If I were given the option today, knowing what I planned to use the sorter for, I might check out the possibility of getting a brand new sorter that was stripped down to the basics for cell line transfection sorting.  I'm thinking something like this perhaps might do the trick.

Monday, December 19, 2011

Is Compensation really necessary?

For some reason, it seems like the idea of compensation gets so much 'publicity'.  Everyone is always talking about compensation and how difficult it is.  New users of flow cytometry tend to think of this idea as something so complex that they end up stumbling on this one idea before they even get started.  So, let's get one thing straight right off the bat;  compensation is easy.  In fact, I'd say compensation is ridiculously easy today, now that you really don't have to do anything.  You just identify your single stained controls, and your software package uses that information to compensate your samples for you.  The real difficulty in performing flow cytometry assays is panel design - determining which colors to use and coming up with a panel where you have the optimal fluorochrome coupled to each antibody to give you the best resolution of your populations.  In fact, I'd go so far as to say that in some cases, compensation isn't even necessary.

Wha, Wha, Wha, What???  That's right ladies and gents - compensation isn't even necessary (in some cases).  And, I'm not just referring to the instances where you're using two colors that don't even overlap, I'm talking about straight-up FITC and PE off a 488nm laser.  Now, before you stop reading and jump over to your Facebook feed let me just assure you that you first learned of the superfluous nature of compensation when you were about 5 years old.  You see, analyzing flow cytometry data with or without compensation is nothing more than a simple "spot the difference" game you use to find in the back of the Highlights magazine while waiting to get your annual immunizations from the pediatrician.  If you take a look at the figure below you may be able to recognize the left panel as the FMO (Fluorescence Minus One) control and the right panel as the sample.  Spot the difference?  Instead of seeing the sun missing on the left and then appearing on the right, let's just substitute a CD8-PE positive population for the sun.  It doesn't really matter if the image is compensated, you're just comparing the differences between the two.


Let's make the comparison a bit more directly.  Here we have some flow cytometry data showing CD3 FITC and CD8 PE.  Our goal is to determine what percentage of the cells are CD3+CD8+.  Obviously, there's some overlap in the emission of the FITC fluorescence into the PE channel when run on a standard 488nm laser system with typical filters.  If I were to hand you this data set and pose the question of "What's the % double positive,"  you could employ the same strategy used above in the spot the difference cartoon without knowing a thing about compensation.  The top two plots below are the FMO controls (in this case, stained with CD3 FITC, but not stained with anything in the PE channel), and the bottom plots are the fully stained sample.  In addition, the left column of plots were compensated using the FlowJo Compensation Wizard, and the right column of plots are uncompensated.  Were you able to "spot the difference"?  If you take a look at the results, you'll see that either way we come up with the same answer.  So what's the point of compensating?

As you can imagine, this is greatly simplifying the situation, and when you start adding more and more colors, you simply cannot create an n-dimensional plot that can easily be displayed on a two-dimensional screen.  This could easily work for 2-color experiments - it could even work for 3-color experiments (maybe using a 3-D plot), but beyond that, you're going to have to do one of two things.  1.  Bite the bullet and get on the compensation train, or 2.  Abandon visual, subjective data display altogether and move to completely objective machine-driven data analysis.  Compensation, much like display transformation is a visual aid used to help us make sense of our data, two parameters at a time.  In our example above, we don't magically create more separation between the CD3+ CD8- and CD3+ CD8+ populations.  The separation between them is the same, we're just visualizing that separation on the higher end of the log scale (when uncompensated) where things are compressed in one case, and on the lower end of the log scale (when compensated) where things spread.  You didn't gain a thing.  

Monday, December 12, 2011

10 Steps to a Successful Flow Cytometry Experiment

I've been doing a good amount of application development recently and have had to "practice what I've preached."  Those of us in the flow cytometry world, especially those in core facilities, like to pontificate all the do's and don'ts of flow cytometry, but how many of us have (recently) struggled through all the intricacies of perfecting a staining assay.  I must say, I was a bit cavalier when I first agreed to set some protocols up for an investigator.  The staining protocols weren't anything novel or difficult, it's just that I personally had not done some of the assays in quite a while.  As I was going through the process I thought, hey, this is not as trivial as one might think...and I've been doing this for a loooooong time.  I could only imagine what someone who is brand new to flow cytometry as a technique must feel like when their PI suggests they use this technology to investigate their hypothesis.  So, I can put forth my top 10 steps to a successful flow experiment with some conviction, because I have now walked in your shoes.

I really wanted to make this a top-10, but as hard as I tried, I could only pare things down to 11.  So, without further adieu I present to you;

10 11 Steps to a Successful Flow Cytometry Experiment


1. Read lots of protocols (not just the reagent manufacturer's protocol).  Let's face it.  If you ask a dozen people how to make a peanut butter and jelly sandwich, you'll end up with 12 different recipes.  The same goes for FCM protocols.  Everyone finds a different part of the protocol worthy of emphasis.  If you read a few of them, you can start to put the entire story together.

2. Know which colors work best on your instrument.  This is probably a bigger deal when you're using a core facility with a few different platforms.  Let me tell you firsthand,  no two cytometers are alike in their capabilities, not even two of the same model of cytometer.  If you're lucky enough to have a flow cytometry core with knowledgable staff, make sure to ask them what their favorite 4, or 5, or 6-color panel is.  They should also be able to tell you what the limitations of certain colors on a given instrument may be.

3. When designing your panel, look for max brightness with min spillover.  Ok, let's say you know what sort of antibodies you want to run, and you know what's available, as far as hardware goes, at your institution.  Now comes the fun part. You have a list of antibodies, and a list of fluorochromes - how do you match them up?  You've probably heard the old adage, put your dim fluorochromes on the antibody that targets abundant antigen, and your bright fluorochromes on antibodies against sparse antigen.  In addition to that you want to minimize spillover - fluorescence from probes that are excited by the same laser and whose emission overlaps.  Spillover = Background, and Background = Diminished resolution.  This takes some effort and a bit of know-how, so consult your friendly flow guru for help, or try out some of the new utilities designed to help with this process (namely CytoGenie from Woodside Logic or Fluorish from Treestar).

4. Titrate your reagents.  What for?  The manufacturer told me to use 5ul per test (usually 10^6 cells in 100ul of volume).  Without jumping on the conspiracy theory bandwagon that reagent manufacturers tell you to use too much antibody so that you'll waste your antibody and have to buy more, I will say that I've found more times than not that the manufacturers suggested dilution is too concentrated. If you want to see why you should titrate your antibodies, check out the figure below.  If you want to see how to titrate your antibodies, click on over to this prior entry to the UCFlow Blog.

CD4 staining of fixed human PBMCs at the properly 
titrated concentration (Left) and the manufacturer's 
recommended concentration (Right).  


Example Staining Worklist 
5.  Outline your plan of attack.  Make a detailed work list of your protocol.  Generic protocols are good to help plan your experiment, but when it comes time to perform the steps of an assay, you really want a work list.  As the name implies, this is a step-by-step recipe of how to execute the protocol.  I usually include the step, duration, volume of reagent, temperature, etc...  While you're performing your assay, take copious notes so you can fine-tune the protocol, adding more detail.  The goal is to be able to hand this work list and the reagents to another user and they should have successful results.  I like to do this in Excel and write in all the cell formulas so that I can type in how many samples I need to stain and have it automagically do all my dilutions for me.  I also have a summary of the buffers needed and quantities at the bottom.  See below as an example.


6.  Always use a Dead Cell Marker. Dead cells can really screw up an analysis.  I guarantee there is a color and assay compatible dead cell marker available for most every experiment you will do.  There's no excuse not to use a dead cell marker, so please, please do it. It makes for a much nicer looking plot, and you really can't do good (dim) double positive enumeration without it.

Two-parameter plot without using an upstream dead cell 
marker (Left) and the same plot after removing dead 
cells (Right).  Note the diagonal population extending 
out of the negative population (encircled with a region 
in the left plot)


7.  Set up your FMO's as a separate experiment, not on your real samples.  I won't discuss the merits of using an FMO control (Fluorescence Minus One), let's just assume you know that it's pretty much a necessity.  What I will say is if you try and set up an FMO control on the day that you're using your precious sample, you're likely to either forget it, or omit it because you think you don't have enough cells. So, if possible, set up your FMO controls ahead of time on a different day so you can take your time getting everything set up properly.  It'd be nice to include it every time, if you have enough sample.

8.  Make compensation controls using beads.  I'm a huge advocate of using capture beads to set up compensation.  It's really a no brainer.  I've written about this subject before.  Even if your single stained controls look fine on cells, I'd still use beads because they're always consistent.

9.  Acquire your samples nice and slow to achieve maximum resolution.  If you go through the trouble of perfecting your staining procedure, now's not the time to screw things up.  On a hydrodynamically focused instrument you'll want to concentrate your sample and run it slow in order to keep a narrow core stream and achieve optimal resolution. If you're using another type of flow cell (such as a capillary a la Millipore or an acoustically focused system like the Attune) you should be more focused on increases in background due to insufficient washing rather than a wide sample core.

10.  Analyze your data a couple of different ways.  Even if I have a clear idea of how to go about the analysis, I'm frequently surprised at how many times I've changed axes or started backwards and found I liked the new way better than the old way.  Backgating is one way to help identify a rare population all the way up through its ancestry.  Make sure to take advantage of your Live cell channel as well as gating out aggregates and removing any time slices where there may have been a drift in fluorescence.

11.  QC your instrument and create an application specific QA protocol.  Science is not about 1-shot deals.  If it's not reproducible, it's not real.  In order to give you the best possible chance of getting reproducible data you'll want to minimize the error contributed by the instrument.  Quality control and Quality assurance cannot be emphasized enough.  By doing something as simple as running beads at your application-specific voltage settings you can ensure that the instrument is in the same state as it was the last time you acquired these samples.  For this, I typically use one of the peaks (peak 4, actually) of the 8-peak bead set.  After I have the samples acquired with the proper voltage settings, I run the beads, create target channels for the peaks and save it as a template.  Next time, all I need to do is dial in the voltage to put the beads in the target.  You'll also want to make an Acquisition template and probably an analysis template too.

Well, there you have it.  Hopefully this will help you focus your attention on some key aspects of setting up a well-thought-out flow cytometry staining protocol.  Of course, this merely scratches the surface of all the things you need to think about.  Did I miss something major?  Feel free to leave a comment with your #12, #13, and beyond.

Friday, December 2, 2011

The Year of Acquisitions

Like most industries, the Flow Cytometry Industry appears to be shrinking, in that the number of players on the industry side of things is getting smaller.  For many years, there were a few big players, namely Becton Dickinson and Beckman Coulter (who they themselves were products of mergers - BD+Ortho, and Beckman+Coulter).  They made instruments and reagents and pretty much sold the whole package.  Seeing the potential for others to capture some of the market share, we experienced a growth of smaller start-ups, either focusing on the hardware or the reagents.  Companies like Cytomation (maker of the MoFlo), and Guava on the instrument side of things introduced some nice products and created some much needed buzz.  A major impact of these companies was that it forced the major companies to invest in R&D and come out with more competitive products.  On the antibody side of things, reagent-focused companies like eBioscience and Biolegend gained popularity.  But, I think a real turning point happened when little-known Accuri Cytometers exploded on the scene with a low-cost, small footprint cytometer with capabilities similar to a FACSCalibur.  They took a page from the Guava playbook and targeted individual labs instead of the typical cytometer purchaser - a core facility.  Soon other companies were seeing the success of these platforms, and the much larger market outside of the core facility.  Companies like Stratedigm, Life Technologies and iCyt started offering smaller sized, less expensive cytometers.  It seemed like the cytometery industry - both on the instrument and reagent side - was expanding.  This lead to competition and innovation.  The old standby's like BD and Beckman Coulter were forced to come up with new and exciting products to maintain their market share.  And then the recession hit.

So, what happens in a recession.  Well, contrary to what you might think, many companies do just fine in a recession.  Of course their growth may slow, but then they also tend to accumulate capital as well.  In fact many companies wind up in a situation where they have lots of cash on hand and are sort of waiting to see what's going to happen.  John Waggoner explains in a USA Today piece (http://www.usatoday.com/money/perfi/columnist/waggon/2011-05-05-cash-in-on-mergers-and-aquisitions_n.htm)  that this past summer, it was estimated that companies in the S&P 500 stock index had a combined $940 Billion in cash.  I postulate that the well-established cytometry companies were/are in a similar boat...but to a much lower degree.

Mr. Waggoner goes on to explain, companies with cash-on-hand basically have three things they're going to do with it.

1.  They can reinvest in the company, hire more people, build more plants, funnel it into R&D, etc...  However, with funding becoming more and more scarce, there's not enough demand in the market to warrant such reinvestment.

2.  They can return money to their investors in the form of dividends.  Some companies are doing this, but probably in moderation.

3.  They can buy another company to position themselves for the recovery.  Mergers and Acquisitions are a pretty huge business in recent years.  In total, M&As are running at a $1.6 Trillion pace for 2011.  A good chunk of this is happening in the healthcare sector.  

Bingo.  Herein lies the recent increase in mergers and acquisitions.  For example, Accuri raises ~$30 Million to get their business going, BD sees the threat and buys them for $205 Million (not a bad ROI for the Accuri Investors).  BD removes the threat, and clears the way for its new flagship, small footprint, easy-to-use cytometer, the FACSVerse.  This works for reagent companies too.  Affymetrix buys eBioscience, EMD-Millipore buys Guava and now Amnis, Life Technologies licenses the acoustic focusing technology to build the Attune, and on and on it goes.  Even bigger name companies like Sony and Danaher are getting into the game.  Sony purchased iCyt to see if it can get its foot into the biomedical research arena, and Danaher purchased Beckman Coulter for who knows what reason.  At any rate, it seems like the industry is attempting to go back to the old days where you'd do all your shopping at one company.  Buy your instrument, reagents, analysis software, and all the rest from one company.  You'll end up having BD labs, Millipore Labs, Life Technology Labs and maybe even Beckman Coulter Labs.  A necessity in the current environment, but I'm sure things will oscillate back to the innovative start-ups taking on the big-boys once again.  So, who's next to be gobbled up?  I'm sure companies like Stratedigm, Blue Ocean, and Cyntellect are hoping their phones will start ringing.

Monday, November 21, 2011

Options for Flow Cytometry Training - FloCyte Review

Flow Cytometry (FCM) isn't the easiest technique to learn.  It actually takes quite a while to master both the hardware and software components to sample acquisition and data analysis - let alone the applications utilizing the aforementioned instrumentation.  For many users of flow (in an academic setting) their first encounter with FCM is likely through a core facility, whereby they'll receive some instruction on how to operate an instrument and then how to analyze the data they collected.  The type and quality of this training varies greatly.  Some institutions I'm familiar with have multi-day courses with wet lab sessions and hands-on instrument time, while others attempt to provide a theoretical base and then do a bit of hand-holding for a few sessions.  The success a user may achieve greatly depends on his or her resourcefulness and overall aptitude for technology.  Some people pick it up quickly; others struggle for years.  I will say that training users in a busy core facility is a huge drain of time and resources.  In our core, for example we basically have an entire F.T.E. just providing training and consultation, so I'm sure that in smaller cores, where it's just one or two people, training has to be an even greater burden.  The question then becomes, how are we to provide the necessary training and attention our users require with the limited time and personnel resources characteristic of a core facility?

There aren't too many options.  Before I jump into an assessment of the FloCyte courses (which is the whole point of this post) let me briefly highlight other possibilities.  FYI, I've personally attended all 3 types of training sessions and have viewed all the resources in #4.  

1.  The Annual Course in Flow Cytometry - This weeklong course alternates between Los Alamos National Labs (or the University of New Mexico) and Bowdoin College in Brunswick, ME.  It is really geared towards users of the technology who already have a basic understanding of the technology.  Also, it focuses on the applications of flow cytometry rather than operation of a flow cytometer, however numerous sections also delve into the hardware components.  There's a pretty cool lab where you can assemble your very own (fairly crude) cytometer.  The cost of the course is about $1800, which includes dorm-style accommodations and meals (transportation is not included).   

2.  Vendor-specific instrument/software training - Most vendors will provide training for their hardware and associated software.  When you purchase an instrument, you might get some free training included with the purchase, but additional training is going to cost you.  As you'd expect, the training is geared towards the operation of that vendor's hardware.  If you were using multiple cytometers from different vendors, this obviously wouldn't be ideal, but if you were using a single platform it might be a good option.  The vendor training will also include some of the basics of cytometry, but again, it will be skewed towards their instruments, their reagents, and their idea of the technology.  It's also pretty expensive, sometimes as much as $2500 per person.

3. Training courses at meeting - Typically when you go to some of the bigger conferences they'll have some workshops on FCM.  Certainly at the CYTO meetings you'll have the opportunity to attend training sessions on various topics.  Also, some of the immunology focused scientific meetings will have some FCM training associated with them (for example, the AIC meeting in Chicago).  Cost for this training is variable, however it's usually limited to conference attendees, so unless you were already planning to attend the conference, it might be really expensive. 

4.  Online utilities - There is quite a lot of information freely available on the web.  You can certainly start at the Purdue University Cytometry Laboratory web site, where there are a bunch of powerpoint slides, movies, and resources freely available.  In addition, companies such as Becton Dickinson, Life Technologies, and Beckman Coulter offer overviews of flow cytometry and flow cytometer technology.  Note that the above links are linked directly to the company's training/support page with the intended materials.  Although these online utilities are readily available and free, you lose the benefit of asking questions and interacting with people who can tailor the training to your specific needs.  

So now, I'll walk you through my experience with the FloCyte Training course offered by FloCyte Services.  I attended the Comprehensive Training Course from 11/15/11 - 11/17/11 held at Spherotech, Inc.  I won't bother taking up space here to give you the rundown of the company and the mission of the training courses.  You can read all about it here.  However, I will note that I attended the Comprehensive training course, which is designed for novice users of flow.  You can see the course curriculum here.

Day 1, as you'd expect, goes over the basic components of flow cytometry.  This is done is a pretty common fashion, and anyone who's gone through the powerpoint slides on the Purdue University Cytometry Laboratory web site will recognize the format.  4-components, Fluidics, Optics, Electronics, and Data Analysis.  All the standard material you'd expect to be here is here.  There was however at least one pretty critical omission - multi-laser systems, laser delays, and how fluorescence emission is spatially separated.  I know this was briefly mentioned during one of the sections, but there was no figure, no reiteration of how it's possible to look at two colors with the exact same emission simultaneously because they're excited by spatially separated laser beams (e.g. PECy7 and APCCy7).  When we broke into small groups to take a look at some of the hardware, I spent most of the time explaining to my other group members how this works.  They were very confused.  The graphics used to talk about emission filtering where all systems like a FACScan or FACSCalibur, which don't have spatially separated beams, and all the light goes through the same "pinhole".  Also on day 1, we finished up with a mathematical explanation of compensation, which went horribly wrong.  The math is complicated and it's probably not something basic users need to understand in order to compensate their data correctly (or, should I say, let FlowJo compensate their data correctly).  Lastly, there was no mention of 1 very critical component to flow cytometry, Quality Assurance and Quality Control.  In all, the basics were handled just fine.  I will say, though, that it seemed to move pretty slow.  I think for the amount of information covered in that first day, it could've have been condensed into a half day.  For example, I feel like the flow basics class given at UCFlow is comparable in it's scope but is completed in about 1.5 -2 hours.  

Day 2 brought in a plethora of applications and tried to reinforce some of the concepts from day 1 while explaining how those concepts effect how you think about the applications.  I think this way of presenting the information is really good.  When we're talking about immunophenotyping, we're also talking about compensation, background due to fluorescence overlap, non-specific binding, etc...   When we're talking about cell cycle, we're also looking at doublet discrimination, coincidence, sample core size, etc...  Here we also start tackling the necessity of controls, including comp controls and the always popular FMO controls.  My big issues with this section solely revolved around the figures.  Many of the figures were at best poor representations of the idea being put forth and at worst blatantly misleading.  This was especially noteworthy in regards to an explanation of biexponential display transformation.  In another instance, the instructors were driving home the idea of how we are to never use quadrants to perform gating on our plots and the very next slide describing FMO controls was filled with quadrants used as gating.  A bit contradictory.

Day 3 was all about stats and panel design.  The stats part was very straight-forward and pretty easy to follow.  The panel design section was good, and covered many of the issues that arise when trying to put together a multicolor panel.  There was an introduction to a utility from Treestar called Fluorish (which I'm not going to complain about because I like it)  however there wasn't any real mention or demonstration of other available utilities like Chromocyte and CytoGenie.  Also, we spent some time going through some data analysis strategies using FlowJo.

The cost for the 3-day Comprehensive course is $700.  The beauty of the course is that it's brought to you (either your institution can host it, or it is hosted nearby) so you don't have to factor in airfare or hotel costs.  But, you'll have to remember that you're getting a comprehensive theoretical overview of flow cytometry, you are not learning how to operate your specific cytometer.  So, if you didn't have a core facility around to show you how to open up FACSDiVa and adjust voltages on your LSRII, you'd still be pretty clueless on how to run your first FCM experiment.  Another positive about the training is that it is modular such that you can attend just days 1 and 2, or just 2 and 3, or even just day 3.  That way if you have some basic knowledge already, you can skip day 1 and just attend days 2 and 3. Lastly, I'll mention that there are a bunch of other, more advanced courses available outside the comprehensive course, including a multicolor compensation course, a course on "phosflow" assays, and even clinical flow cytometry.  

The instructors are well-respected flow cytometry professionals with years of experience under their belts.  They presented most of the material in a clear and concise way.  There was, at times, some confusion regarding what a figure was trying to describe, but this was due to the fact that the slides were recently re-done and the instructors were not 100% comfortable with them.  I feel like I want to give them a pass on that, but then again, I did pay $700 on this course and expected a very polished delivery.  All things considered, they did an excellent job.

I could see this working in a couple of ways.  1.  You get some initial training on how to operate your cytometer from your core facility and then attend days 2 and 3 of the comprehensive course.  2.  You could attend the entire comprehensive course and then go through the specific instrument training given by your core facility.  3.  Get trained by your core, start running experiments, and then jump in on one of the advanced courses offered by FloCyte.  If you're not fortunate enough to have the support of a core facility, then this makes the FloCyte courses even more attractive.  Relying on them for the basic theoretical training, and then the instrument vendor for training on the actual equipment is probably your best bet. 

Friday, November 11, 2011

Cytometer Service Contract or Self Insure: the Wal-Mart effect.

Instrument maintenance and repair is typically not a huge factor when deciding on a piece of equipment to purchase.  People are much more concerned with the practical things like how many lasers can I put on, how fast can I run my samples, or more simply, can it handle the applications I plan to run?  Even after we have the instrument installed in the lab we're not really thinking about maintenance and repair because we're on the "full-warranty high."  If something breaks, what does it matter?  The company will come out the next day and repair it at no cost.  Right about the halfway point through the warranty period the thought hits you - I'm going to have to start paying for service on this thing.  Herein lies the dilemma.

Although there are many variations, in general there are two schools of thought here.  The first involves some level of service agreement (full, partial, lasers only, instrument minus lasers, etc...) and the second is akin to an "insurance" plan.  By the way, before I go on, I should state that I'm writing this from the standpoint of a private academic institution (namely the University of Chicago), however private companies, public institutions, or individuals may have a vastly different experience.  Let me briefly explain these two systems of instrument maintenance.

Service agreements.  About 6-8 months into your warranty period, a friendly company representative will contact you to try and sell you on a full service contract.  This basically extends the type of service experienced during the warranty period.  Labor and parts will be covered under the service contract costs you pay annually.  Be sure to get a list of what are typically called 'consumable parts'.  These items are parts that will not be covered under the service contract.  Consumables are commodities that are intended to be used up quickly and therefore are not parts that could undergo some type of failure.  It is this failure of a part that is covered by the service contract.  Consumables can be expensive; sometimes as much as $1000 - $2000 for a single item that may only last 6-12 months.  You'll need to be sure to add these costs to your total cost of ownership.  Full service contracts are fantastic.  You get rapid response times, an endless supply of new parts, and generally I find the quality of service is of a higher standard.  The downside is the expense.  You can plan on spending about 10% of the original purchase price yearly on a full service contract, which means that after 10 years, you'll have bought the instrument twice.  You can also look into service contracts that cover only parts of the instrument, such as a 'lasers-only' contract.  This may cover some of the major expenses that might hit, but some of the routine fluidics issues or electronics issues would still need to be paid out-of-pocket.  Lastly, you don't need to rely solely on the Original Equipment Manufacturer (OEM) for service.  In some cases, third party companies will either provide the service agreement (serve as a middle man between you and the OEM) or there are companies that can actually come out and fix some of your older generation instruments.

Insurance.  If you pass on the service agreement route, either with the OEM or a 3rd party company, you'll need to carefully make a plan on how you will pay for problems that pop up.  This can be done by including a line item on your budget and simply inserting the cost of the service contract.  Then you'd need to pay for any repairs using those available funds.  If you don't use all the funds then you have a surplus and possibly a way to do some upgrades or save it for a rainy day.  If, however, you end up paying out-of-pocket more than you have put away as insurance then you could have some trouble with your institution.  The insurance method also has some unintended consequences including the possibility that your service calls may be bumped to the bottom of the list if the OEM services customers on service contract first.  Secondly, I've noticed that the field service engineers tend to do the minimum to get the instrument functional again.  This is not to say they're lazy or anything, they're actually doing you a favor by not replacing non-essential parts, and performing the work quickly so the hourly labor charge is not too high.  However, this sometimes leads to more frequent trips to a site to fix a related part that breaks shortly after the instrument was put back into service.

So, what do we do at UCFlow?  Well, a hybrid, of course.  If you can anticipate which instruments will likely have more problems over the years, then you can keep your instruments running for many years without hassel for a lot less money.  Seems impossible, but here are a few tricks.  Obviously, the first thing you're going to do is monitor performance very carefully during the warranty period.  If odd things are happening monthly, or even quarterly, it may be a good idea to consider a service contract.  If you can find out from current owners of the same model instrument whether they have many service calls, that might help make the decision.  Also, if you or your lab is familiar with the innards of the cytometer and aren't afraid to do things like replace valves, regulators, or even lasers then you should be less likely to buy a service contract.  Lastly, the more instruments you have, the more money you'll be wasting on service contracts.  Let's say you have 6 instruments, and the service contract is $15,000 each ($90K total).  It's unlikely that all 6 cytometers will have multiple issues in a given year, so let's say you have 2 instruments with major problems (multiple service calls with big ticket items totaling $30K).  The other 4 run pretty smoothly, and maybe require another couple of service calls for minor issues ($15K).  If you pay out-of-pocket then you'll basically be paying 50% of the cost of a full service contract.  This might be a good year; some other years might not be so favorable.  However, it's likely that many years you'll be under budget and a couple of years you might be over budget.

As an example, I'll share a few stories of my experience.  We had multiple 1st generation FACSCantos that were breaking down monthly.  We were actually paying more out-of-pocket than the cost of a full service contract, so we went ahead and put them on contract.  This was a no brainer.  We also had an old LSRII that, over the course of 6 years had not had a single service call placed on it.  All we've had to do is perform the standard Preventative Maintenance (PM).  We never had a contract on this instrument.  After 6 years of spending nothing on this instrument, we had 2 lasers die at the same time, which required replacement at the cost of $50K.  The service contract cost was $22K per year, so 6 years times $22K = $132K, and actual costs were $50K, a 62% savings.   It is a situation like this that tells us to err on the side of NOT getting a service contract until an instrument proves to be unreliable.  Once it is deemed unreliable we either place it under service contract, or get rid of it and find a more reliable alternative.  It sometimes seems like a gamble, and if I only had 1 or 2 instruments, I'd likely have them on service contracts, but since I have the luxury of duplicate technology and the power of numbers, I'm able to take that gamble and the odds are usually in my favor.

By the way, of the 16 instruments we have in the lab, 3 are on service contract (only the aforementioned early generation FACSCanto-A).  We're able to save money by having a high number of instruments.  We can also negotiate better contracts if desired.  Larger volumes typically lead to better prices per unit.  This is what we call the Wal-Mart effect.  If that's not your case, then you'll likely want to lean more towards the service contract route.