The immune proteins have important roles in neuronal plasticity and some are found in neurons as well as microglia or astrocytes (Boulanger, 2009; Rivest, 2003), and we will briefly review the role of the six proteins tested in this study in brain function (shown schematically in Fig. 6). CD14 is critical for the function of two Toll-Like receptors, TLR 2 and 4, which are expressed by microglia as well as astrocytes and neurons (Bsibsi et al., 2002; van Noort and Bsibsi, 2009). Cathepsins, including Ctsf and Ctss, are found in microglia where they are important for the function of MHC class II molecules and are also secreted from microglia and may be involved in cytokine processing (Nakanishi, 2003; Wang et al., 1998). B2m, which is part of the MHC class I complex, is found in many neurons, including dopaminergic neurons, and is critical for neuronal plasticity, including long-term potentiation (Corriveau et al., 1998; Huh et al., 2000; Linda et al., 1999). IL-1 is one of the most prevalent and important cytokines and its actions are regulated by an endogenous antagonist,
