What is Acellular Dermal Matrix (ADM) made of?

Composition of Acellular Dermal Matrix (ADM)

Acellular dermal matrix (ADM) is primarily made of decellularized dermal tissue that has been processed to remove DNA and antigenic donor cells while preserving the extracellular matrix components including collagen, fibronectin, elastin, laminin, glycosaminoglycans, and hyaluronic acid. 1

Source Materials

ADMs are derived from two main sources:

• Allogenic (human): Processed from cadaveric human skin 2, 3
• Xenogenic (animal): Derived from mammalian sources, typically:
  • Porcine (pig) dermal tissues
  • Bovine (cow) dermal tissues 1

Processing and Structure

The manufacturing of ADM involves several key processes:

1. Decellularization: Removal of cellular components and DNA to create an immunologically inert scaffold 3

2. Cross-linking variations: ADMs are divided into two subgroups based on processing:

   • Cross-linked (partially remodeling): Contains additional links that provide better resistance to mechanical stress for longer periods 2
   • Non-cross-linked (completely remodeling): Allows for more complete integration with host tissue 2

3. Sterilization: Available in either aseptic or sterile forms 2

Structural Components

The preserved extracellular matrix in ADM includes:

• Basement membrane: Provides structural foundation
• Dermal layer: Rich in collagen that serves as a scaffold
• Growth factors: Essential for supporting wound healing 4

Biological Function

ADM functions as a biological scaffold that:

1. Supports cell infiltration: Provides a framework for host fibroblasts to migrate into the matrix

2. Promotes vascularization: Facilitates blood vessel formation and integration

3. Enables tissue remodeling: Gradually becomes incorporated into the recipient's own tissue 3, 1

4. Supports epithelialization: Provides a platform for mucosal epithelization in certain applications 4

Clinical Considerations

When selecting an ADM for clinical use, important factors include:

• Storage requirements: Some require specific temperature conditions

• Rehydration needs: Preparation may involve rehydration steps

• Thickness and size options: Available in various dimensions for different applications 2

• Cost implications: ADMs are generally expensive, which may limit their use in certain clinical scenarios 1

It's important to note that while ADMs offer significant advantages in terms of reducing donor site morbidity and providing structural support, their long-term durability is still being evaluated in clinical studies 2.

Human Acellular Dermal Matrix (ADM) is particularly notable for its low infection rates (1.6%) when used in emergency repair of abdominal wall hernias, though recurrence rates of approximately 15.9% have been reported in longer-term follow-up 2.