The Early Regenerative Events in the Human Tympanic Membrane After In Vivo Traumatization
Elnaz Sepehri1,2, Cecilia Engmér Berglin1,3, Yan Liu4
1Division of Ear, Nose and Throat Diseases, Department of Clinical Sciences, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
The Laryngoscope
|July 21, 2026
Summary
Human tympanic membrane (TM) traumatization triggers early regenerative responses. Key proliferative regions, including the annulus, malleus, and unattached pars tensa (UPT), show activation within 20 hours post-injury.
Area of Science:
- Otolaryngology
- Regenerative Medicine
- Wound Healing
Background:
- The human tympanic membrane (TM) possesses regenerative capabilities.
- Understanding the early cellular response to TM injury is crucial for developing effective healing strategies.
Purpose of the Study:
- To investigate the early regenerative response in the keratinocyte layer of the human TM after in vivo trauma.
- To identify specific cellular markers and regions involved in the initial healing process.
Main Methods:
- Human TMs were subjected to in vivo trauma (phenol or scratching) and harvested after 20 hours.
- Immunohistochemistry was employed using markers for epidermal progenitor cells (CK19, p63, α6-integrin) and proliferation (Ki-67).
- Staining intensity and patterns were evaluated by blinded assessors across different TM regions.
Main Results:
- All assessed protein markers were detected in all TM regions 20 hours post-traumatization.
- CK19, p63, and Ki-67 showed upregulation in regenerative areas like the annulus and malleus.
- CK19 and α6-integrin were significantly upregulated in the traumatized unattached pars tensa (tUPT) compared to the untraumatized side (uUPT).
Conclusions:
- Traumatization of the human TM initiates a regenerative response within 20 hours.
- The study confirms the regenerative potential of the annulus and malleus and highlights early proliferation in the UPT.
- Findings provide valuable insights for enhancing future TM healing strategies.
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