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Background: Fibrosis in the renal biopsy is associated with poor long term outcome in many kidney diseases. However, fibrosis occurs at a late stage when the kidney is irreversibly damaged. Molecular biology techniques are currently being investigated to identify early prognostic markers in kidney diseases. Reverse transcriptase real-time PCR (RT-qPCR) is a highly sensitive technique capable of detecting small changes in gene expression, Transforming growth factor-1 (TGF-1) is a key mediator of fibrosis and is expected to be increased in damaged tissues. This is a pilot study to investigate the feasibility of the using RT-qPCR to study gene expression of TGF-31 in human kidney tissues.
Methods: RNA was extracted from normal and diseased human kidneys with fibrosis and reverse transcribed. TGF-1 gene expression was studied by multiplex RT-qPCR using cyclophilin A as a housekeeping gene. Relative gene expression was calculated from 2-DDCT method.
Results: The expression TGF-1 in three different areas of the same kidney were similar The expression of TGF-b1 was 4-5 fold higher in disease kidney tissues compared to normal (p < 0.001).
Summary: TGF-P1 gene expression can be measured from human kidney using RT-qPCR. There are minimal effects of tissue sampling on gene expression levels, hence tissue obtained from a kidney biopsy should be representative of the whole kidney cortex. The expression of TGF-1 is higher in fibrotic kidneys. Future studies are necessary to determine if the TGF-1 gene expression markers can predict disease progression.
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