PRL and schizophrenia: For example, seven proteins (interleukin-16, fatty acid binding protein, ferritin, C-reactive protein, myoglobin, prolactin, and complement factor H) were found to predict the improvement in positive symptoms, and two proteins (matrix metalloproteinase 2 and insulin) were found to predict improved negative symptoms in patients with schizophrenia treated with antipsychotics (Schwarz, Guest, Steiner, Bogerts, & Bahn, 2012).