Gene expression profiles of disc tissues and peripheral blood mononuclear cells from patients with degenerative discs

The objective of this study was to analyze gene expression profiles of intervertebral disc samples and peripheral blood mononuclear cells (PBMCs) from patients with degenerative discs using Agilent's Human 1A Oligo microarray. RNA samples from disc tissue and PBMCs were obtained from patients with degenerative discs and from subjects in a control group. RNA samples were reverse-transcribed into Cy5-labeled cRNA, combined with a Cy3-labeled reference and hybridized to oligonucleotide microarrays. Microarrays were scanned by Gene-Pix 4000B and data were analyzed using GenePixPro 3.0 software. The microarray data were validated in the same RNA samples by qRT-PCR analysis of selected genes. For the disc tissue, the mRNA expressions of 522 genes changed obviously in the degeneration group, accounting for approximately 2.64% of all analyzed transcripts. These included transcription-related, ion channel and transport protein, receptor, protein synthesis and modifying, growth factor, etc. For PBMCs, the expressions of 62 genes changed obviously in the patients in the degeneration group. These changes included ion channel, transport protein, transcription-related, DNA synthesis and repair, metalloprotease, immune globulin-related, growth factor-related, extracellular matrix-related, adhesion molecule, etc. Analyzed on the association of the differential expression of genes between disc tissue and PBMCs, some genes were not compatible. The course of intervertebral disc denegation is a complicated dynamic process, however, and may mainly be local pathogenesis. These findings furnish new data for the mechanistic investigation of degenerative discs.