IL2 and schizophrenia: There was no significant difference in the production of IL-2 by patient and control T cells stimulated with plate-bound anti-CD3 at concentrations of 0 μg/ml, 0.01 μg/ml, 0.1 μg/ml and 1 μg/ml (figure 4A), demonstrating that insufficient IL-2 production is not responsible for lower T cell proliferative responses observed in schizophrenia patients.