In favor of this theory, many recent clinical data have shown elevated concentrations of inflammatory markers (including TNF-α, IL-6, IL1-β, and CRP) in the blood and in the cerebral spinal fluid of patient with major depression (Kim et al., 2007; Simon et al., 2008; Howren et al., 2009; Dowlati et al., 2010). Here, CRP is linked to major depressive disorder.