RE: Multiplex bead array question

If your protein is precipitated the array will turn into an
agglutination assay. Cytometry can be used for looking at such assays as
well...
 
The only way to avoid this is to use porous beads that bind inside
instead of on the bead. However in a normal ELISA one would have taken
the result for valid, precipitated or not.
 
 
Regards
 
Gerhard

	-----Original Message-----
	From: Katherine Pilkington
[mailto:katherine.pilkington@imvs.sa.gov.au] 
	Sent: 21 November 2006 06:08
	To: Cytometry Mailing List
	Subject: Multiplex bead array question
	
	

	Fellow Flowers,

	 

	I have been searching the archives in vain for some technical
assistance with multiplex bead arrays.	I recently assisted an
investigator with analysis of samples using a Bender mouse Th1/Th2
multiplex kit.	Whilst the standards were beautiful, when it came to
analysis of her serum samples, the smaller bead population had vacated
the gated area.  From the amount of large debris to be seen on the axis
at the top right corner of the FS/SS plot I assume she observed severe
aggregation of her samples.  Has anyone else experienced this problem?
I heard a rumour that serum can be tricky to get information cytokine
from, but many of the websites claim good reproducibility from serum
samples so I am assuming it is possible, with just a little fine tuning.
Her samples were not lipemic, and had been clarified prior to freezing.

	 

	If you have had experience with this problem and have found a
solution I would very much appreciate hearing from you.

	 

	Furthermore, I am about to road test a CBA kit from BD for human
cytokines, so if anyone has any useful technical hints about sample
preparation etc above and beyond what is stated in the instruction
manual that may help me successfully complete this assay I'd appreciate
that also.

	 

	Regards,

	Kate

	 

	--

	Katherine Pilkington

	Flow Cytometrist and Cell Sorter

	Detmold Family Imaging Centre

	Institute of Medical and Veterinary Science 

	Frome Road, Adelaide South Australia 5000

	Ph: +61 8 8222 3322