Assessment of plasma and tissue fibronectin EIIIB splice variant expressions measured serially using RT-PCR in a wound model of rabbits

Background: Fibronectin (FN) is an indispensable part of the extracellular matrix. During regeneration or wound healing, the plasma form of FN is incorporated into the fibrin clots to form a temporary fibrin-FN matrix, and also locally synthesized cellular FN migrates to the clot to regenerate the injured tissue. We aimed to examine wound tissue FN EIIIB and plasma FN EIIIB expression levels in an experimental wound healing model in rabbits. Methods: Plasma and tissue EIIIB splice variant expressions were measured serially with RT-qPCR in a cutaneous wound model of rabbits. Results: Tissue FN expression increased as beginning on day 3 and continued to increase on days 6 and 9, reaching maximum expression at day 12 before starting to decrease. On the contrary to the tissue levels, plasma FN levels gradually decreased until day 15 when expression returned to the initial values. Conclusion: The findings of the current study support that tissue EIIIB expression level increases during wound healing; and plasma EIIIB expression level decreases minimal changed. This is in contrast to reports where plasma FN provisionally helps ECM formation. Therefore, our data show an essential role of EIIIB at the tissue level in accelerating the wound healing process. The RT-qPCR method in our experimental setup can provide more accurate and precise results compared to the antibody-based methods