Incubation of murine macrophages with B. burgdorferi (Bb) and IFNγ alters the expression of chemokine genes. Murine macrophages were incubated with medium alone, B. burgdorferi, IFNγ, or B. burgdorferi and IFNγ concurrently for 8 hours. RNA was extracted from cells and analyzed using real-time RT-PCR for the following transcripts: CXCL1 (A), CXCL9 (B), CCL12 (C), CXCL3 (D), CXCL11 (E), CXCL16 (F), CXCL2 (G), and CXCL10 (H). CXCL1, CXCL2, and CXCL3 attract neutrophils; the remainder attract mononuclear leukocytes. Fold changes are relative to the level of transcripts in macrophages incubated with medium alone.