Exudates absorption and proteases trapping in venous leg ulcers

In venous leg ulcer (VLU), the impaired healing has been shown to be associated with excessive levels of protease activities such as matrix metalloproteinases (MMPs) and elastases found in exudates. The present study focused on exudates absorption and proteases trapping capacity of a new generation of polyacrylate superabsorbent, Tegaderm superabsorber (TS), compared with a traditional dressing such as Zetuvit.

We studied the proteases implicated in VLU (MMP-1, MMP-2, MMP-9 and PMN elastase). Absorption was tested using an artificial exudate like fluid, over 30 minutes. The protein trapping ability was obtained using ELISA assays (enzyme-linked immunosorbent assay) to determine the amount retained by the dressings from spiked fluid samples.

TS had a higher exudate absorption capacity (72.8±1.7%) compared with the standard dressing (36.5±1.6%), and was also able to trap and retain proteases while the standard dressing released them. The difference was shown to be much larger for MMP-2 and PMN elastase.

In our knowledge, this is the first comparative in vitro study evaluating absorption capacity as well as protease trapping capacity of a polyacrylate dressing for the four most implicated proteases in VLU. TS could be an appropriate alternative to improve the management of VLU by trapping MMPs and PMN elastse with a particularly high affinity for MMP-2 and PMN elastase.