Relative MIP-2γ mRNA and protein expression in astrocytes. (a) RT-PCR analysis of MIP-2γ expression in purified primary astrocyte cultures. Levels of MIP-2γ mRNA were increased in primary cultures of astrocytes exposed to LPS or TNF-α compared with buffer-treated astrocytes (control). β-actin was used as a positive control. (b) MIP-2γ is up-regulated after exposure to LPS or TNF-α, shown by an ELISA for MIP-2γ in the conditioned media of astrocytes. Data are expressed as the mean ± SEM from three to four independent experiments. *P <0.05; **P <0.01 significantly different from buffer-treated control (ANOVA followed by a Dunnett’s test). (c) Representative western blot probed for MIP-2γ and β-actin simultaneously. Levels of MIP-2γ in cell lysates derived from primary astrocytes exposed to LPS or TNF-α were increased compared with buffer-treated astrocytes (control). ANOVA, analysis of variance, LPS, lipopolysaccharide; MIP-2γ, macrophage inflammatory protein-2γ; SEM, standard error of the mean; TNF-α, tumor necrosis factor α.