T-Helper 2 Lymphocyte Immunophenotype Is Associated With Iatrogenic Laryngotracheal Stenosis

Laryngoscope. 2019 Jan;129(1):177-186. doi: 10.1002/lary.27321. Epub 2018 Nov 13.

Abstract

Objective/hypothesis: This prospective controlled human and murine study assessed the presence of inflammatory cells and cytokines to test the hypothesis that immune cells are associated with fibroproliferation in iatrogenic laryngotracheal stenosis (iLTS).

Methods: Inflammation was assessed by histology and immunofluorescence (IF), quantitative real-time polymerase chain reaction (qRT-PCR), and flow cytometry of cricotracheal resections of iLTS patients compared to normal controls. An iLTS murine model assessed the temporal relationship between inflammation and fibrosis.

Results: iLTS specimens showed increased inflammation versus normal controls (159/high power field [hpf] vs. 119/hpf, P = 0.038), and increased CD3 + T-cells, CD4 + cells, and CD3+/CD4 + T-helper (TH ) cells (all P < 0.05). The inflammatory infiltrate was located immediately adjacent to the epithelial surface in the superficial aspect of the thickened lamina propria. Human flow cytometry and qRT-PCR showed a significant increase in interleukin (IL)-4 gene expression, indicating a TH 2 phenotype. Murine IF revealed a dense CD4 + T-cell inflammatory infiltrate on day 4 to 7 postinjury, which preceded the development of fibrosis. Murine flow cytometry and qRT-PCR studies mirrored the human ones, with increased T-helper cells and IL-4 in iLTS versus normal controls.

Conclusion: CD3/CD4 + T-helper lymphocytes and the proinflammatory cytokine IL-4 are associated with iLTS. The association of a TH 2 immunophenotype with iLTS is consistent with findings in other fibroinflammatory disorders. The murine results reveal that the inflammatory infiltrate precedes the development of fibrosis. However, human iLTS specimens with well-developed fibrosis also contain a marked chronic inflammatory infiltrate, suggesting that the continued release of IL-4 by T-helper lymphocytes may continue to propagate iLTS.

Level of evidence: NA Laryngoscope, 129:177-186, 2019.

Keywords: Laryngotracheal stenosis; T-lymphocytes; fibrosis; human study; murine model.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD3 Complex
  • CD4 Antigens
  • Disease Models, Animal
  • Fibrosis / immunology
  • Flow Cytometry
  • Humans
  • Interleukin-4 / analysis*
  • Laryngostenosis / immunology*
  • Laryngostenosis / pathology
  • Larynx / immunology
  • Larynx / pathology
  • Mice
  • Mice, Inbred C57BL
  • Real-Time Polymerase Chain Reaction
  • Th2 Cells*
  • Trachea / immunology
  • Trachea / pathology
  • Tracheal Stenosis / immunology*
  • Tracheal Stenosis / pathology

Substances

  • CD3 Complex
  • CD4 Antigens
  • Interleukin-4