Immunogen sequence: WSFGILLWEI YSFGRVPYPR IPLKDVVPRV EKGYKMDAPD GCPPAVYEVM KNCWHLDAAM RPSFLQLREQ LEHIKTHELH. CSK is a tyrosine kinase that has been shown to downregulate the activity of SRC oncoprotein through phosphorylation of its carboxy terminus. Sin