Objectives. To identify genes which are more highly expressed in the peripheral blood mononuclear cells (PBMC) of patients with spondyloarthropathy (SpA), rheumatoid arthritis (RA) and psoriatic arthritis (PsA), in comparison to normal subjects. Methods. A 558-gene microarray was used as a screening tool to select a panel of such genes from PBMC of these subjects and of normal subjects. Results were then validated by reverse transcription-polymerase chain reaction (TR-PCR). Results. The following genes were more highly expressed in arthritis patients than in normal subjects: macrophage differentiation marker MNDA (myeloid nuclear differentiation antigen), MRP8 and MRP14 (migratory inhibitory factor-related proteins); signaling molecules JAK3 (janus kinase 3) and MAP kinase p38 (mitogen-activated protein kinase); receptors TNFR2/p75, CCR1, CXCR4 and integrin β1; and the cytokines/chemokines interleukin (IL)1 β AND IL-8. Expression of CXCR4 was unexpectedly high among all arthritis subjects. Using RT-PCR, ELISA and immunohistology, expression of stromal cell-derived factor 1(SDF-1) was demonstrated in arthritis joints.