Differential expression of rituximab responders vs. non responders on 3 different blood cell types

We have recruited 9 RA patients starting immunotherapy with rituximab. The same day of the first infusion we obtained the three different cell type samples: whole blood (preserved in PaxGene tubes), B cells (using negative selection) and CD4+ T cells (using negative selection). At week 24 of treatment we determined the clinical response using the RelDas score. All tissue samples were processed in parallel (i.e. RNA extraction and microarray profiling with Illumina WG6 Beadchip) in order to minimize the technical variability. The three datasets were normalized separately using quantile normalization. After performing differential expression analysis between Responders and Non-Responders we identified significantly expressed genes in all three cell types. The most significant gene candidates were validated using the Taqman Real-Time PCR assays.