This antiserum was tested for use in ELISA and by western blot. Specific conditions for reactivity should be optimized by the end user. Expect a predominant band approximately 42 kDa in size corresponding to p42 MAP Kinase (ERK2) by western blotting in the appropriate cell lysate or extract. p42 MAP Kinase (ERK2) is a ubiquitous protein kinase target for Ras and Raf. The following cell lines have been assayed by immunoblot and were found to be positive for p42 MAP Kinase (ERK2) using this reagent: U937, HeLa, NIH-3T3, RAW 264.7, LNCaP and HEK whole cell lysates.