Can Western blot be completely replaced by ELISA?

[hanhan2008]

Sorry for this naive question. I've been wondering what are the advantages and disadvantages of Western blotting compared to ELISA. Thanks in advance!

[Cat]

No, it cannot be replaced by ELISA. Just to give you some idea:
ELISA allows to detect presence of the antigen or Ab in the sample and evaluate their concentrations.
Western blot allows to do the same thing + other things (like isolate that protein, etc.)
ELISA is faster and easier than Western.

[jonmoulton]

Western gives size information about the analyte, while ELISA gives only concentration information.

It's like trying to replace Northerns with RT-PCR: OK for some applications, but if you need to know the size of the analyte you need to do the electrophoretic step on the original sample (and not just to separate PCR products).