Anatomical Features Around Eustachian Tube in Eosinophilic Otitis Media With Eosinophilic Sinusitis

Planar Cell Polarity in the Multiciliated Epithelial Lining of the Mouse Eustachian Tube

OBJECTIVES

Planar cell polarity (PCP) signaling, essential for uniform alignment and directional beating of motile cilia, has been investigated in multiciliated epithelia. As a complex structure connecting the middle ear to the nasopharynx, the eustachian tube (ET) is important in the onset of ear-nose-throat diseases. However, PCP signaling, including the orientation that is important for ciliary motility and clearance function in the ET, has not been studied. We evaluated PCP in the ET epithelium.

STUDY DESIGN

Morphometric examination of the mouse ET.

METHODS

We performed electron microscopy to assess ciliary polarity in the mouse ET, along with immunohistochemical analysis of PCP protein localization in the ET epithelium.

RESULTS

We discovered PCP in the ET epithelium. Motile cilia were aligned in the same direction in individual and neighboring cells; this alignment manifested as ciliary polarity in multiciliated cells. Additionally, PCP proteins were asymmetrically localized between adjacent cells in the plane of the ET.

CONCLUSIONS

The multiciliated ET epithelium exhibits polarization, suggesting novel structural features that may be critical for ET function.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:3795-3801, 2024.

Establishment of novel immortalized middle ear cell lines as models for otitis media

Objective

Otitis media (OM) is among the most frequently diagnosed pediatric diseases in the US. Despite the significant public health burden of OM and the contribution research in culture models has made to understanding its pathobiology, a singular immortalized human middle ear epithelial (MEE) cell line exists (HMEEC-1, adult-derived). We previously developed MEE cultures from pediatric patients with non-inflamed MEE (PCI), recurrent OM (ROM), or OM with effusion (OME) and demonstrated differences in their baseline inflammatory cytokine expression and response to stimulation with an OM-relevant pathogen lysate and cytokines. Herein, we sought to immortalize these cultures and assess retention of their phenotypes.

Methods

MEE cultures were immortalized via lentivirus encoding temperature-sensitive SV40 T antigen. Immortalized MEE lines and HMEEC-1 grown in monolayer were stimulated with non-typeable Haemophilus influenzae (NTHi) lysate. Gene expression (TNFA, IL1B, IL6, IL8, MUC5AC, and MUC5B) was assessed by qPCR.

Results

Similar to parental cultures, baseline cytokine expressions were higher in pediatric OM lines than in HMEEC-1 and PCI, and HMEEC-1 cells were less responsive to stimulation than pediatric lines.

Conclusion

Immortalized MEE lines retained the inflammatory expression and responsiveness of their tissues of origin and differences between non-OM versus OM and pediatric versus adult cultures, supporting their value as novel in vitro culture models for OM.

Pathophysiological Link Between Chronic Rhinosinusitis and Ear Disease

PURPOSE OF REVIEW

In the clinical practice, patients affected by chronic rhinosinusitis (CRS) commonly complain of otologic symptoms. This review aims to describe the available literature evidence assessing the relationship between CRS and ear illnesses published in the last 5 years.

RECENT FINDINGS

Available evidence suggests a higher prevalence of otologic symptoms in patients suffering from CRS, affecting up to 87% of patients. These symptoms may be related to Eustachian tube dysfunction, which improves after treatment for CRS. A few studies suggested a potential but not confirmed role of CRS in cholesteatoma, chronic otitis media, and sensorineural hypoacusis. A special type of otitis media with effusion (OME) may occur in patients with CRS, which seems to respond well to new biologic therapy. Ear symptoms appear to be highly prevalent in patients with CRS. So far, the available evidence is robust only for Eustachian tube dysfunction, which has been shown to be particularly impaired in CRS patients. Additionally, the Eustachian tube function appears to improve after treatment for CRS. Finally, interesting preliminary data were described for eosinophilic otitis media, as it appears to respond well to the treatment with biologics.

Intractable otitis media - Pathogenesis and treatment of Eosinophilic otitis media (EOM) and otitis media with Antineutrophil cytoplasmic antibody (ANCA) -associated vasculitis (OMAAV)

Intractable otitis media is resistant to antimicrobial therapy, tympanostomy ventilation tube insertion, and surgery. In children, intractable acute otitis media, pathological tympanic membrane due to prolonged otitis media with effusion (OME), tympanic membrane atelectasis, and adhesive otitis media are common. Contrarily, in adults, otitis media caused by drug-resistant pathogens, tuberculous otitis media, cholesterol granuloma, malignant otitis externa (skull base osteomyelitis), eosinophilic otitis media (EOM), and otitis media with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (OMAAV) are common and require differentiation. Among them, EOM is increasing along with eosinophilic upper respiratory tract diseases, such as bronchial asthma and eosinophilic chronic rhinosinusitis (ECRS), a subgroup of chronic rhinosinusitis with nasal polyps (CRSwNP). EOM is associated with adult-onset bronchial asthma and is characterized by viscous middle ear effusion and middle ear mucosa thickness with eosinophilic infiltration, which requires treatment with glucocorticoids according to disease activity and symptoms. Recently, OMAAV was proposed because of the similarities in clinical features and therapeutic effects. The clinical course of OMAAV is characterized by a relatively rapid increase in the bone conductive hearing threshold, which progresses over 1-2 months, without response to antimicrobial agents or tympanostomy ventilation tube insertion, and in some cases, is complicated by facial paralysis and hypertrophic pachymeningitis. This new concept may explain the pathogenesis and clinical presentation of many cases of intractable otitis media, the cause of which was previously unknown. Although making a diagnosis of OMAAV is relatively easy based on the clinical course, such as vascular dilatation of the tympanic membrane and positive ANCA titer, it is often difficult because the ANCA titer becomes negative with previous administration of glucocorticoids. In adults with intractable otitis media, ANCA titers must be measured before glucocorticoid administration. Treatment consisted of remission induction therapy with a combination of glucocorticoids and immunosuppressive drugs.