Growth factors are signaling proteins essential to cellular processes such as proliferation, migration, and angiogenesis. In chronic wounds, local deficiencies or imbalances in growth factors can impair healing. Biologic dressings, including amniotic membrane allografts and extracellular matrix-derived products, are increasingly used in wound management due to their ability to deliver or support the activity of endogenous growth factors.

This article examines how various biologic dressings differ in growth factor content, structure, and clinical context. Understanding these differences can help providers select products aligned with specific wound presentations and healing objectives.

The Role of Growth Factors in Chronic Wound Healing

Wound healing is a complex, multi-phase process involving hemostasis, inflammation, proliferation, and remodeling. Key growth factors implicated in wound healing include:

  • Epidermal Growth Factor (EGF): Stimulates epithelial cell proliferation.
  • Fibroblast Growth Factor (FGF): Promotes angiogenesis and fibroblast activity.
  • Vascular Endothelial Growth Factor (VEGF): Enhances new blood vessel formation.
  • Transforming Growth Factor Beta (TGF-β): Regulates inflammation and extracellular matrix synthesis.
  • Platelet-Derived Growth Factor (PDGF): Recruits immune cells and fibroblasts.

In chronic wounds, levels of these factors may be diminished or functionally inhibited. Biologic grafts provide structural and biochemical cues to address these deficits1.

Comparing Growth Factor Content by Graft Type

Amniotic Membrane Allografts

Amniotic membranes are rich in growth factors including EGF, FGF, and TGF-β. Processing methods (e.g., dehydration, cryopreservation) influence the preservation of these proteins. Dual-layer constructs often retain both the amnion and chorion, which may offer a broader range of cytokines and structural integrity2.

  • Typical Profile: EGF, FGF-2, TGF-β, IL-10, and TIMPs.
  • Observed Use Case: Applied weekly in diabetic foot ulcers and venous leg ulcers.

Acellular Dermal Matrices (ADMs)

ADMs are derived from human or animal dermis and processed to remove cellular components while preserving the extracellular matrix. They support fibroblast migration and may facilitate endogenous growth factor activity by preserving integrin-binding domains3.

  • Typical Profile: No exogenous growth factors; structural matrix promotes host cell infiltration and signaling.
  • Observed Use Case: Large or tunneling wounds requiring mechanical durability.

Umbilical Cord-Derived Products

These include Wharton’s jelly and umbilical cord membrane-based grafts. Rich in hyaluronic acid and growth factors, they offer hydration and biochemical support4.

  • Typical Profile: HGF, VEGF, TGF-β, and HA-binding proteins.
  • Observed Use Case: High-exudate wounds or when anti-inflammatory effects are prioritized.

Decellularized Porcine Small Intestine Submucosa (SIS)

SIS products preserve structural collagen and bioactive components. Though primarily structural, some retained bioactivity may influence local growth factor signaling5.

  • Typical Profile: Primarily structural proteins with trace bioactive residues.
  • Observed Use Case: Surgical and pressure wounds requiring scaffolding.

Considerations for Clinical Application

When evaluating biologic dressings for growth factor support, providers should consider:

  • Wound type and etiology: Diabetic, venous, pressure, or surgical wounds may respond differently.
  • Inflammatory status: Products with retained anti-inflammatory cytokines may benefit wounds with prolonged inflammation.
  • Moisture management: Highly exudative wounds may require absorbent constructs with growth factor retention.
  • Application frequency: Some products are applied weekly, others less frequently depending on resorption and wound response.

Regulatory Context and Labeling

Under FDA 21 CFR Part 1271, most biologic dressings are regulated as HCT/Ps intended for homologous use. Growth factors present in these products are not classified as therapeutic agents but are considered part of the native tissue matrix. Labeling does not quantify individual growth factor concentrations.

Summary for Providers

Growth factors are central to wound healing, and biologic dressings provide varying degrees of growth factor support depending on source tissue and processing. Amniotic membrane allografts offer preserved biochemical activity, while ADMs and SIS provide structural support that may enhance endogenous signaling.

Understanding these profiles enables clinicians to match graft characteristics to wound needs, supporting more precise biologic dressing selection within the bounds of regulatory and clinical practice.

References

  1. Barrientos S, Stojadinovic O, Golinko MS, Brem H, Tomic-Canic M. Growth factors and cytokines in wound healing. Wound Repair Regen. 2008;16(5):585–601.
  2. Koob TJ, Lim JJ, Massee M, Zabek N, Denoziere G. Properties of dehydrated human amnion/chorion composite grafts: implications for wound repair and soft tissue regeneration. J Biomed Mater Res B Appl Biomater. 2014;102(6):1353–1362.
  3. Reing JE, Zhang L, Myers-Irvin JM, Cordero KE, Freytes DO, Heber-Katz E, et al. Degradation products of extracellular matrix affect cell migration and proliferation. Tissue Eng Part A. 2009;15(3):605–614.
  4. Litwiniuk M, Grzela T. Hyaluronic acid in inflammation and tissue regeneration. Wounds. 2014;26(3):77–83.
  5. Badylak SF. The extracellular matrix as a biologic scaffold material. Biomaterials. 2007;28(25):3587–3593.

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