Immunocytochemistry assessment of vocal fold regeneration after cell‐based implant in rabbits

• Published in: Laryngoscope investigative otolaryngology Vol. 9; no. 5; pp. e70007 - n/a
• Main Authors: Nicolas, Larissa, Mandl, Hanna, Schrader, Feng, Long, Jennifer L.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01-10-2024; Wiley
• Subjects: angiogenesis; Antibodies; Antigens; cell‐based implant; Endoscopy; human adipose derived stem cells; Laboratory animals; Larynx; Leukocytes; Original Research; Rabbits; Scars; smooth muscle actin; Stem cells; Transplants & implants; vocal fold regeneration; cell‐based implant; human adipose derived stem cells; smooth muscle actin; angiogenesis; vocal fold regeneration
• ISSN: 2378-8038; 2378-8038
• DOI: 10.1002/lio2.70007

Objective
Cell‐based outer vocal fold replacement (COVR) offers a potential treatment for severe vocal fold scarring or cancer reconstruction. Previous work in rabbits using human adipose‐derived stem cells (ASC) in fibrin suggested that a hybrid structure emerged within 2 months, containing both implanted and host cells. This project uses immunocytochemistry to better define the phenotypic fate of implanted cells and features of the extracellular environment.
Methods
Immunocytochemistry was performed on sections collected from rabbits 2 months after COVR implantation or scar surgery. Cellular targets included human leukocyte antigen (HLA), CD31, and smooth muscle actin (SMA).
Results
HLA was present in all implanted sections and was used to identify human cells. In adjacent sections, HLA‐positive cells were identified expressing CD31. SMA was not identified in the same cells as HLA. These markers were also present in injured vocal folds not receiving COVR. SMA protein content did not differ according to treatment.
Conclusions
Implanted human ASC persist in rabbit vocal folds. Some appear to express CD31, an endothelial marker. Smooth muscle actin, a marker of myofibroblast phenotype, was present in all sections regardless of treatment, and was not identified in hASC. Host cells also infiltrate the structure, producing a hybrid host‐graft vocal fold.
Cell‐based outer vocal fold replacement (COVR) using human adipose‐derived stem cells (ASC) in fibrin was investigated in rabbits. Immunocytochemistry revealed that implanted human ASC persist in rabbit vocal folds, with some expressing CD31, an endothelial marker, whereas smooth muscle actin (SMA), a marker of myofibroblast phenotype, was present in all sections regardless of treatment and was not identified in hASC.