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Isotype control? - (May/03/2006 )

Hi,
could anyone tell me: In flow cytometry (and probably all antibody-based methods) what is the isotype control good for and how does it actually look like?

Thank you!

Paja

-Paja-

It's a negative control for aspecific binding.

When you label a cellular receptor with conjugated antibody, there's always a background present of antibody that hasn't bound to your receptor but is still not washed away. To make sure that the signal you're getting is from receptor binding and not background, you should see a clear difference in fluorescence intensity when comparing isotype control and antibody bound to a cellular target that's present on your cells.

-vairus-

QUOTE (vairus @ May 3 2006, 12:35 PM)
It's a negative control for aspecific binding.

When you label a cellular receptor with conjugated antibody, there's always a background present of antibody that hasn't bound to your receptor but is still not washed away. To make sure that the signal you're getting is from receptor binding and not background, you should see a clear difference in fluorescence intensity when comparing isotype control and antibody bound to a cellular target that's present on your cells.



OK, I understand, but how does such a control physically look like? Is it the conjugate itself or what? unsure.gif

And Vairus, thank you for the response.

Paja

-Paja-