Profiling of differentially expressed genes in wound margin biopsies of horses using suppression subtractive hybridization.

This research is focused on comparing gene expression in normal, intact skin and wound margin biopsies in horses to identify the genes that play a role in wound repair. The successful identification of these differential genes could help to prevent and treat impaired healing.

Objective and Methodology

• The main goal of this study was to identify the genes that play a critical role in normal wound repair in horses, as disturbances in gene expression could potentially result in excessive scarring or hindered healing.
• To achieve this aim, the researchers used a technique called suppression subtractive hybridization (SSH), a method to identify and isolate differentially expressed genes. This technique helped the researchers understand the genes responsible for the wound healing process by comparing gene expression in normal intact skin (IS) and wound margin (WM, tissue surrounding the wound) biopsies.
• The study specifically looked at 7-day-old wounds in horses, because this is a critical period in the wound healing process. Tissue samples were taken from both normal intact skin (IS) and wound margins (WM) at this time.

Findings

• The researchers established a subtracted (WM-IS) cDNA library, in which cDNA from the intact skin was subtracted from the wound margin cDNA. This allowed the identification of 226 nonredundant cDNAs that were differentially expressed between the two, highlighting the genes that were being switched on or off during the wound healing process.
• Some of the genes identified were previously known to be expressed in wound repair including COL1A2, annexin A(2), the pro-alpha(3)-chain of type 6 pro collagen, beta actin etc. The discovery of these known genes supports the validity of the study’s experimental design.
• A RT-PCR assay further confirmed the upregulation or induction of some specific genes(COL1A2, MMP1, dermatan sulfate proteoglycan 2, cluster differentiation 68, cluster differentiation 163, and disintegrin and metalloproteinase domain 9) during the healing process.
• Interestingly, many of the cDNAs that were identified had not been previously associated with wound repair, including spermidine/spermine-N-acetyltransferase, serin proteinase inhibitor B10, and sorting nexin 9. These genes were found to be highly expressed during wound repair, suggesting that they may play a role in regulating the wound healing process.

Conclusion and Future Direction

• The findings of the study led to the identification of novel genes that are differentially expressed while wound repair in horses.
• The authors recommended that future research should look into correlating the changes in mRNA levels for each identified genes with the spatiotemporal protein expression within tissues. This will provide a more comprehensive understanding of the specific role that these genes play in the wound healing process.