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bands sizes with sectreted protein - (Apr/10/2008 )

Hi Everyone,
I was wondering if someone could answer my question: I have concentrated conditioned media by immunoprecipitation and then when I run this on a 12% gel I only see protein bands at the sizes 6-7Kd (a large band), a smaller band at 16kDa, and then smaller bands at 25Kda and larger with massive amount of protein at ~60kDa upward. I am aware the large band is probably serum but is this a normal pattern for conditioned media or should i be seeing a greater range of bands in the lower region like you do with cell lysates? I have attached a copy of the membrane so you can see the pattern. Thank you in advance.


I don't understand, you did IP didn't you? If you IPed your media why you still see all of these bands. Usually, I see them when I concentarte media without IP or when I run medi without concentration.

I would IP my protein of interest if it's secreted in the media, this way you get rid of all these bands.

let me know