[Histological observation and vascularization evaluation of porcine acellular dermal matrix processed with matrix
Objective:
To investigate the histological changes and vascularization of the porcine acellular dermal matrix (P-ADM) processed with matrix metalloproteinase 7 (MMP-7) (P-ADM-pm) after implanted into rats.
Methods:
Sixty-two pieces of porcine reticular layer dermis which were from the pig abdominal skin and obtained by using a mechanical method, were randomly divided into group A (n = 31) and group B (n = 31). The porcine reticular layer dermis in 2 groups were treated with decellularization (P-ADM), then the P-ADM in group B were treated with processing by MMP-7 (P-ADM-pm). Thirty adult male Wistar rats were selected. P-ADM (group A) and P-ADM-pm (group B) were subcutaneously transplanted into the left and right fascia lacuna, respectively. The implants were harvested from 6 rats at 3, 7, 14, 21, and 28 days after implantation, respectively. Gross, histochemical, and immunohistochemical observations, and scanning electron microscopy (SEM) examination were performed to observe host cells, microvessels infiltration and histological changes in the implants.
Results:
No rat died in the experiment, incision healed well and no obvious inflammatory reaction was seen in all rats. Gross observation suggested that the implants of 2 groups were encapsulated by a thin layer of connective tissue at 7 days after implantation. With the time of implantation, the microvessels increased and coarsened, and the changes of group B were more obvious than those of group A. At 21 days, the microvessels of 2 groups decreased, and the implants of group B showed complete vascularization. The histochemical and immunohistochemical observations showed that group A had more severe inflammatory response than group B. Fibroblasts and microvessels in group B appeared in the superficial zone of implant at 3 and 7 days after implantation and they could be observed in the center zone of implant at 14 and21 days. However, fibroblasts and microvessels in group A appeared in the superficial zone of implant at 3 and 14 days and they could not be observed in the center zone of implant at 28 days. Fibroblasts and microvessels of group B were significantly more than those of group A (P < 0.05). SEM examination showed that more fibroblasts and new collagen fibrils were observed in group B at 14 days.
Conclusion:
The host response to P-ADM-pm is similar to normal wound healing, and P-ADM-pm as implantable scaffold material plays a good template conduction role.
Insights
Matrix metalloproteinase-7 (MMP-7) processed porcine acellular dermal matrix (P-ADM-pm) showed enhanced vascularization and reduced inflammation in rat implants. P-ADM-pm acts as a superior scaffold material, promoting better healing and tissue regeneration.
Area of Science:
- Biomaterials Science
- Tissue Engineering
- Regenerative Medicine
Background:
- Porcine acellular dermal matrix (P-ADM) is a promising scaffold for tissue regeneration.
- Optimizing P-ADM for enhanced host integration and vascularization is crucial for clinical success.
Purpose of the Study:
- To evaluate the histological changes and vascularization of MMP-7 processed P-ADM (P-ADM-pm) after implantation in rats.
- To compare the host response to P-ADM-pm with unmodified P-ADM.
Main Methods:
- Porcine reticular dermis was decellularized to create P-ADM.
- P-ADM was further processed with MMP-7 to create P-ADM-pm.
- P-ADM and P-ADM-pm were implanted subcutaneously into Wistar rats and harvested at various time points for analysis.
Main Results:
- P-ADM-pm exhibited significantly enhanced vascularization and fibroblast infiltration compared to P-ADM.
- Histochemical and immunohistochemical analyses revealed a less severe inflammatory response in P-ADM-pm implants.
- Scanning electron microscopy showed increased fibroblasts and new collagen fibrils in P-ADM-pm at 14 days.
Conclusions:
- MMP-7 processing improves the host response to P-ADM, leading to accelerated vascularization and reduced inflammation.
- P-ADM-pm serves as an effective template for tissue regeneration, mimicking normal wound healing processes.
- P-ADM-pm demonstrates potential as an advanced implantable scaffold material.
