Are Specific Gene Expressions of Extracellular Matrix and Nucleus Pulposus Affected by Primary Cell Cultures Prepared from Intact or Degenerative Intervertebral Disc Tissues?

To determine the gene expression patterns of nucleus pulposus (NP) in cell cultures obtained from degenerated or intact tissues. Whereas 12 of the cases were diagnosed with lumbar disc herniation and had undergone lumbar microdiscectomy, 12 cases had undergone traumatic intervertebral discectomy and corpectomy, along with discectomy after spinal trauma. NP-specific markers and gene expressions of the reagents of the extracellular matrix in the experimental setup were tested at the 0th, 24th, and 48th hours by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Visual evaluations were simultaneously made in all samples using invert and fluorescence microscopy. Vitality and proliferation analyses were evaluated by UV spectrophotometer. As a method of statistical evaluation, Spearman was used for categorical variants, and the Pearson correlation was used for variants with numerical and plain distribution. No association was found either between the tissue type and times (r=0.000; p=1.000) or between the region that the tissue was obtained from and hypoxia transcription factor-1 alpha (HIF-1α) gene expression (r=0.098; p=0.245). There was no correlation between cell proliferation and chondroadherin (CHAD) expression or between type II collagen (COL2A1) and CHAD gene expressions. It was found that CHAD and HIF-1α gene expressions and HIF-1α and COL2A1 gene expressions affected cell proliferation. Cell culture setups are of paramount importance because they may influence the pattern of changes in the gene expressions of the cells used in these setups.