Re:Cell detachment medium (was: EVC 304 abort rate)

From: David Coder (d_coder@MSN.com)
Date: Mon May 20 2002 - 07:41:55 EST


Here it is: http://www.innovativecelltech.com/accutase.html from Phoenix
Flow in San Diego.

Dave
========================================
David M. Coder, Ph.D.
Consultant in Cytometry
email: d_coder@msn.com or dcoder1@hotmail.com
tel./messages: 206-499-3446
----- Original Message -----
From: "Ress, S, Stan, Dr" <sress@uctgsh1.uct.ac.za>
To: cyto-inbox
Sent: Monday, May 20, 2002 4:58 AM
Subject: Re: EVC 304 abort rate


> Hi David,
>
> Please could you look up details  on the magic  Elixer that gets
> adherent cells off in great shape, once you're on 'terra firma', and
> post to discussion list, or else reply to me, it sounds like
> something I could  really use!!
>
> Many thanks,
>
> Stan
>
>
>
> > Reply-to:      "David Coder" <d_coder@MSN.com>
> > From:          "David Coder" <d_coder@MSN.com>
> > To:            Cytometry Mailing List <>
> > Subject:       Re: EVC 304 abort rate
> > Date:          Wed, 15 May 2002 08:38:56 -0700
>
> >
> > Very useful comments on sorting improvements. I agree that a major
problem
> > is the debris level. Starting earlier in the process of getting adherent
> > cells into suspension would be using the magic elixir that Phoenix Flow
> > Systems sells (sorry, Kevin,  I can't remember the name and I'm too
cheap to
> > plug into the Airphone here at 35,000ft and pull up your webpage). Not
only
> > do you get a much cleaner cell prep, but you'll have a higher yield of
> > viable cells (less cell damage, less debris).  Secondly, you may also
> > benefit from using a nozzle with a larger diameter. If the cell is
occupying
> > too much of the stream as it exits the nozzle, stream perturbations
result.
> > Also, I'm guessing here, but a larger cell in a smaller drop and drops
alone
> > may charge differently as they leave the stream thus giving rise to ugly
> > sort streams. Granted, as you go up in nozzle diameter, sort rates will
> > drop, but there's probably an optimal set of conditions where sort rate
and
> > abort are best.
> >
> > Dave
> > ========================================
> > David M. Coder, Ph.D.
> > Consultant in Cytometry
> > email: d_coder@msn.com or dcoder1@hotmail.com
> > tel./messages: 206-499-3446
> > ----- Original Message -----
> > From: "Mostowski, Howard S." <mostowski@cber.fda.gov>
> > To: cyto-inbox
> > Sent: Monday, May 13, 2002 11:34 AM
> > Subject: RE: EVC 304 abort rate
> >
> >
> > >
> > > David,
> > >
> > > The problem is not you, but the cells themselves, that is not
> > > exactly accurate neither.  The cell are in a messy "FACS" media.  This
> > > usually happens with any of the adherent cell and specially with cells
> > that
> > > are fixed.  I too have seen this problem appear, but it is around 50%
at
> > 10
> > > to 12k cells/sec at a sheath pressure of 14.  You probably noticed two
> > other
> > > facts [pardon the pun], but if you reduce the your sample pressure
thus
> > > reducing the number of cells/sec your instrument has to make a
decision,
> > the
> > > abort rate drops dramatically. You did not mention if you had the
> > Accu-drop
> > > attachment, but if so you would notice that it is virtually impossible
to
> > > hold your side streams perfect even though they where with the control
> > > beads. I use a two droplet-delay setting.
> > > Great now you know at least two of us has seen this phenomenon; that
> > > does not explain what is happening and what I can do to somewhat
alleviate
> > > it.  So here goes.
> > > 1. Filtering is a must as it will remove a great deal of the
> > > artifacts cast off from the damaged cells as well as un-dissolved
> > > preservative. You probably will not get rid of all the cellular debris
as
> > > more garbage is constantly being produce by the damaged cells sitting
in
> > > your sample tubes.  You might think you could reduce the problem by
> > > increasing the threshold [I keep my FCS threshold at 20], it will not
> > work.
> > > The reason is, even though the artifacts are out of the picture
> > > electronically they are still there physically.  Because they are
still in
> > > the equation, your instrument has to make a decision about cell +
debris
> > and
> > > it is not in your favor.
> > > 2. The other way to reduce the abort rate is as mentioned above is
> > > to reduce your sample pressure to below 3000 cells/sec.
> > > 3. The third way is to increase the concentration of cells. By
> > > increasing the concentration of cell incorporated with a reduction of
> > > cell/sec allows you to have a sample stream of a smaller diameter;
thus
> > > reducing the chance of debris coming past you beam at the same time,
but
> > > here you have to have a feather touch on your on your sample
differential
> > > knob.
> > > I hope this helps somewhat, Cheers and good luck.  If any ones else
> > > has some other techniques, please put it in the open format, because I
am
> > > always ready to learn frame someone more wiser.
> > >
> > > Howard
> > > -----Original Message-----
> > > From: Corry, David [mailto:David.Corry@uwe.ac.uk]
> > > Sent: Monday, May 13, 2002 7:23 AM
> > > To: cyto-inbox
> > > Subject: EVC 304 abort rate
> > >
> > >
> > >
> > > Hi all,
> > >
> > > I've recently started analysing ECV304 endothelial cells on my
FACSVantage
> > > and
> > > have been having problems with a high co-incidence abort rate -
typically
> > > 75%+!!
> > > The cells are fixed with 1% paraformaldehyde/1% FBS in PBS and stained
> > with
> > > FITC or RPE conjugates. The problem doesn't seem to be as bad with
unfixed
> > > cells or with some of the other adherent cell lines I use e.g. C20/A4
> > > chondrocytes.
> > > Could it be a problem with the fixing protocol? Anyone got any ideas
or
> > > suggestions?
> > >
> > > Thanks in advance
> > >
> > > Dave
> > >
> > > ----------------------------------------
> > > David Corry
> > > Centre for Research in Biomedicine
> > > Faculty of Applied Sciences
> > > University of the West of England
> > > 0117 344 3397
> > > Email: David.Corry@uwe.ac.uk
> > >
> > >
> > >
> >
> >
> >
> >
>
>



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