1O2-induced glutathionylation of CRP can be reversed by the chemical reductant TCEP, or an enzymatic glutaredoxin (Grx) system. Panel A: Representative immunoblotting image of glutathionylated CRP monomer with or without addition of TCEP. Panel B: Representative immunoblotting image of glutathionylated CRP monomer with or without addition of the Grx system (see Materials and methods for details). Panel C: OD ratio (OD lane n/OD lane 4, n = 4, 8) of glutathionylated CRP monomer from immunoblotting data in panel A without (white bar) or with (black bar) addition of TCEP. Panel D: OD ratio (OD lane n/OD lane 4, n = 4, 8) of glutathionylated CRP monomer from immunoblotting data in panel B without (white bar) or with (black bar) addition of the enzymatic Grx system. Statistical differences are indicated as follows: *p < 0.05 vs lane 4 (panel A; monomer); #p < 0.05 vs lane 4 (panel B; monomer). Each blot is a representative image from one of three experiments carried out on independent samples. Data in panels C and D are presented as mean ± SD from three independent experiments.