There is a growing body of evidence to suggest a role for inflammatory processes in schizophrenia. Research has shown that there are increased concentrations of pro-inflammatory cytokines, such as interleukin 6 and 8 (IL-6, IL-8) and tumour necrosis factor a (TNFa) in the serum of people with schizophrenia. The presence of a number of other markers of inflammation have also been demonstrated; for example, there is an increase in serum phospholiapse activity. In people with schizophrenia, the blood-cerebrospinal fluid (CSF) barrier is impaired and there is an increase in the concentration of serum intercellular cell adhesion molecule (sICAM) and immunoglobulin G (IgG) in the CSF. The activation of immune cells, such as monocytes and T-lymphocytes, and the production on the free radical NO are also indicators for the presence of an inflammatory process in schizophrenia.