Expression data from PBMC treated with rabbit anti-thymocyte globulin (rATG) or horse ATG (hATG)

We performed microarray to compare gene expression patterns of PBMC treated with rATG or hATG. Fold changes were compared using 2-way ANOVA tests for untreated, rATG- and hATG-treated PBMC. In PBMC treated with 10 ug/mL rATG, compared with untreated PBMC, 478 genes showed up-regulation, and 341 genes showed down-regulation at 24 hours using 10% FDR and 2-fold change cutoff. Immediately striking was that 10 ug/mL hATG had affected many fewer genes than did rATG: only 3 genes were up-regulated and 6 genes were down-regulated at 24 hours in hATG-treated PBMC. When we compared rATG with hATG, rATG induced up-regulation of 268 genes and down-regulation of 95 genes. These genes belong to the categories of immune response (64 genes), cytokine-cytokine receptor interaction (36 genes), regulation of cell proliferation (24 genes), cell cycle (23 genes), cell growth (8 genes), apoptosis (7 genes), and others. Keywords: different treatment PBMC from healthy controls were cultured with rATG or hATG (each at 10 ug/mL) in 10% FCS/RPMI 1640 at 37C for 24 hours, PBMC without drugs were used as controls. Total RNA was extracted with the RNeasy kit (Qiagen, Valencia, CA). RNA purity was assessed by spectrophotometry. Probes were prepared using standard Affymetrix protocols and hybridized to Affymetrix HG-U133A 2.0 arrays (Affymetrix, Santa Clara, CA)