An isolated antibody, consisting of an anti-glutathionylated eNOS antibody, wherein the anti-glutathionylated eNOS antibody has been generated against an immunogen consisting of a peptide that includes glutathione; a first linker; an eNOS peptide; a second linker; and a T-cell epitope; and wherein the anti-glutathionylated eNOS antibody is adapted to recognize redox modulated eNOS proteins.