CCL2 and myeloid sarcoma: Recent studies have shown that CCL2 concentrations in CSF and serum from early active MS patients are reduced, but increase during remission [Bartosik-Psujek and Stelmasiak, 2005; Mahad et al. 2002; Nakajima et al. 2004a; Sorensen et al. 1999, 2001, 2004].