Cell adhesion molecules and cytokines in middle ear effusions in children with or without recent acute otitis media

The Role of Serum Adhesion Molecules s-ICAM-1 and s-VCAM-1 in Chronic Otitis Media Pathogenesis: A Prospective Controlled Study

The aim of this study was to determine the levels of soluble intracellular adhesion molecule-1 (s-ICAM-1) and soluble vascular cell adhesion molecule- 1 (s-VCAM-1) in patients with chronic otitis media (COM) according to the disease profile and to compare with ears without otitis media. Eighty-nine patients had ear surgery were included in the study prospectively. 78 patients who underwent tympanomastoidectomy included in the study group and 11 patients who underwent exploratory tympanotomy included in the control group prospectively. The level of s-ICAM-1 and s-VCAM-1 measured with ELISA technique. s-ICAM-1 and s-VCAM-1 levels compared between COM specific diseases group and with the control group. Levels of s-ICAM-1 and s-VCAM-1 measured as 584.5 ± 165.3 ng/ml and 541.1 ± 237.3 ng/ml in patients with COM, 384.4 ± 99.6 ng/ml and 551.7 ± 336.4 ng/ml in the control group respectively. The mean of s-ICAM-1 detected significantly higher in the COM group (p < 0.001). But the mean of s-VCAM-1 in the COM and control group was similar (p = 0.895). Also, s-ICAM-1 was significantly higher in patients with cholesteatoma, ossicular chain defects and tympanic membrane retraction (p = 0.037, 0.045 and 0.032, respectively). Although s-VCAM-1 level was not affected by cholesteatoma, ossicular chain defect and tympanic membrane retraction (p = 0.178, 0.243, p = 0.164, respectively). While the mean of s-ICAM-1 was detected significantly higher in COM and related pathologies therefore, increased serum levels may reflect the severity of the disease. But, s-VCAM-1 was not affected by COM and COM-specific diseases.

Lack of the hyaluronan receptor CD44 affects the course of bacterial otitis media and reduces leukocyte recruitment to the middle ear

BACKGROUND

CD44 is a multifunctional molecule that plays major roles in both leukocyte recruitment and tissue proliferation. Since mucosal hyperplasia and leukocyte infiltration of the middle ear cavity are major features of otitis media, we evaluated the role of CD44 in the pathophysiology and course of this disease in a mouse model of middle ear infection. Expression of genes related to CD44 function were evaluated using gene arrays in wild-type mice. The middle ears of mice deficient in CD44 were inoculated with non-typeable Haemophilus influenzae. Histopathology and bacterial clearance were compared to that seen in wild-type controls.

RESULTS

We observed strong up-regulation of CD44 and of genes related to its role in leukocyte extravasation into the middle ear, during the course of acute otitis media. Mice deficient in CD44 exhibited reduced early mucosal hyperplasia and leukocyte recruitment, followed by delayed resolution of infection and persistent inflammation.

CONCLUSIONS

CD44 plays an important role in OM pathogenesis by altering the mucosal growth and neutrophil enlistment. Targeted therapies based on CD44 could be useful adjuncts to the treatment of middle ear infections.

Cigarette smoke activates NFκB-mediated Tnf-α release from mouse middle ear cells

OBJECTIVES/HYPOTHESIS

: Cigarette smoke exposure is a significant risk factor in the development of otitis media. NF-κB is a transcription factor known to mediate cigarette smoke effects in multiple cell types. We hypothesized that stimulation of murine middle ear epithelial cells (MEEC) with cigarette smoke condensate (CSC) activates NF-κB resulting in upregulation of proinflammatory cytokines.

STUDY DESIGN

: In vitro model of cultured murine middle ear epithelial cells.

METHODS

: Time course CSC stimulation of MEEC was performed. Antibody microarrays were then utilized to simultaneously measure 40 inflammatory cytokines. Enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcriptase-polymerase chain reaction were performed to validate and further evaluate array results. Luciferase reporter assays were performed to evaluate NF-κB activation with CSC in MEEC. Chromatin immunoprecipitation (ChIP) assays were performed to determine whether CSC induces NF-κB interaction with the Tnf-α promoter.

RESULTS

: Multiple cytokines showed significant increases with CSC exposure. ELISA studies demonstrated that Tnf-α secretion increased the most. CSC stimulation likewise increased Tnf-α mRNA abundance and induced promoter activity 4.8-fold in a Tnf-α reporter plasmid. Reporter assays demonstrated 4.84-fold activation of NF-κB with CSC. ChIP assays demonstrated NF-κB binding to canonical κB sites in the Tnf-α promoter with CSC stimulation.

CONCLUSIONS

: CSC activates NF-κB in MEEC. Furthermore, this activation results in CSC induced Tnf-α promoter activation, gene expression, and levels in cell secretions. Laryngoscope, 120:2508-2515, 2010.

Serum intercellular adhesion molecule 1 variations in young children with acute otitis media

Acute otitis media (AOM) is an inflammatory reaction in the middle ear, most often occurring in young children. Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis are the most common bacteria isolated. Intercellular adhesion molecule 1 (ICAM-1) is involved in the innate immune response to infection by microorganisms, in effective antigen presentation, and in subsequent T-cell activation. Here we prospectively studied levels of serum soluble ICAM-1 (sICAM-1) before, at the time of, and after antimicrobial treatment of AOM in a group of 138 children ages 6 to 30 months. Middle ear fluids were collected by tympanocentesis to identify otopathogens. We found that (i) serum levels of sICAM-1 were significantly higher in S. pneumoniae-, nontypeable H. influenzae-, and M. catarrhalis-infected children than in well children (P < 0.001), confirming that a systemic inflammatory response occurs during AOM; (ii) sICAM-1 levels varied from no elevation (110 ng/ml) to elevation to high levels (maximum, 1,470 ng/ml) among children with AOM; (iii) in paired samples, sICAM-1 levels increased 4- to 20-fold when children developed AOM compared to their sICAM-1 levels before infection; and (iv) the level of sICAM-1 returned to the pre-AOM level at the convalescent stage of AOM after successful antimicrobial therapy. We conclude that AOM often causes a systemic inflammatory reaction, as measured by elevation of the serum sICAM-1 level, and that a high variability in sICAM-1 responses occurs with the presence of otopathogens during AOM.

Role of nasal allergy in chronic secretory otitis media

Nasal allergy seems to be one of the important causes of chronic secretory otitis media (SOM) in children and adults. Chronic SOM is unequivocally related to disturbed function of the eustachian tube, which facilitates communication of the middle ear with the nasopharynx, nasal cavity, and indirectly with paranasal sinuses. The most serious consequences of chronic SOM are decreased elasticity of the tympanic membrane and hearing impairment. Allergic reactions in the nasal mucosa leading to release of various mediators result in development of three types of nasal response characterized predominantly by nasal obstruction. Eustachian tube functions can be affected directly by the mediators released in the nasal mucosa or indirectly by the nasal obstruction. Nasal challenges with allergens performed by rhinomanometry, combined with tympanometry and eventually audiometry, may be a useful diagnostic supplement for this disorder.

Proinflammatory and immunoregulatory cytokines in the middle ear effusions

OBJECTIVE

The recognition of inflammatory mediators in middle ear effusions and their correlation with clinical parameters may allow better understanding of many complex events leading to development of permanent sequelae of otitis media and hopefully help to develop future interventions. The aim of the study was to evaluate the presence and level of proinflammatory interleukin (IL) 1beta, IL-6 and immunoregulatory IL-10 in the middle ear effusions, their mutual correlation and relationship with age, duration of the illness, number of episodes of acute otitis media, and presence of retraction pockets.

METHODS

The study included 25 children (41 ears), who had been scheduled for myringotomy with the insertion of tympanostomy tubes due to otitis media with effusion. The interview (duration of the illness, number of episodes of acute otitis media), clinical and audiological examination was conducted according to the developed examination check list. Middle ear effusions (MEE) were collected aseptically, the samples centrifuged and supernatant frozen at a temperature of -80 degrees C. The IL-1beta, IL-6 and IL-10 were assayed using enzyme-linked immunosorbent assay (ELISA) kits incorporating monoclonal antibodies and the ETI system reader. The nonparametric Mann-Whitney U test was used for statistical analysis and Pearson's linear correlation coefficient was calculated.

RESULTS

IL-1beta was detected in 80% of examined effusions, IL-6 in 78%, and IL-10 in 88%. There was a strong statistical correlation between IL-1beta and IL-6 concentrations (r=0.627, P=0.000), as well as IL-6 and IL-10 (r=0.66, P=0.000) No statistically significant correlation was found between levels of cytokines and clinical parameters.

CONCLUSIONS

Proinflammatory and immunoregulatory cytokines participate in middle ear inflammatory response. The lack of direct correlation between IL-1beta and IL-10 may be responsible for chronic character of the disease. As no correlation between the levels of cytokines and clinical parameters was found it seems that the time of duration of inflammation rather than its intensity measured by levels of cytokines is the main factor in development of middle ear mucosa pathology.

Comparison of cytokine levels in bilateral ear effusions in patients with otitis media secretoria

OBJECTIVE

The aim of this study was to clarify the site of primary pathology in otitis media with effusion.

STUDY DESIGN AND SETTING

The levels of the inflammatory mediators TNF-alpha, TNF-beta, IL-1beta, IL-8, IL-6, IL-4, IL-2, IL-5, IL-10, and IFN-gamma were measured in 54 pairs (108 samples) using specific enzyme-linked immunosorbent assays (ELISAs).

RESULTS

The levels of pro-inflammatory cytokines TNF-alpha, TNF-beta, IL-1beta, IL-8, anti-inflammatory cytokines IL-5, IL-4, IL-10, IL-6, and cytokines with immunoregulatory potential IFN-gamma, IL-2 were different between both ears of the same patient.

CONCLUSION

The results suggest that in one individual both ears have different immunological processes or rates and this has implications on using the opposite ear as a control in clinical trials.

SIGNIFICANCE

Profiles of interlink of examined cytokines within the samples of both ear effusions were significantly different. A significant bilateral difference was found in the levels of IFN-gamma.