**3.1.2 Monocytes**

Monocytes are activated during ECC and play a role in thrombin formation, but also they can produce a potent arsenal of pro-inflammatory cytokines (IL-1β, TNF-α, IL-6, IL-8, MCP-1 and CD40 ligand), reactive oxygen substances and prostaglandin (Borregaard & Cowland 1997). Monocytes also release different types of enzymes (elastase, collagenases, lipooxygenase), interferons, growth factors, matrix proteins. Moreover, monocytes produce nitric oxide (Paparella et al. 2002)
