The Establishment Of Animal Model Of Allergic-related Otitis Media With Effusion And Study On Its Pathological Mechanism

Objective:1.Using ovalbumin(Albumin,OVA)systemic sensitization and nasal stimulation to construct a BALB/c mouse model of allergy-related otitis media with effusion.2.and observe the changes in the mucosa of the "middle ear-eustachian tube-upper respiratory mucosa complex".3.Compare the dynamic expression of interleukin 5(IL-5)in the delayed phase of allergy and the aquaporin5(AQP5)in the middle ear mucosa.Methods:To establish a mouse model of allergic-related otitis media with effusion sensitizated with ovalbumin(OVA)and aluminum hydroxide,then intranasal challenged by OVA.Eighteen BALB/c mice were selected and randomly divided into blank control group,model group Ⅰ(intranasally stimulated for 2 weeks)and model group Ⅱ(intranasally stimulated for 4 weeks),with 6 mice in each group.After successfully established,the middle ear(ME)and nasal mucosa were obtained.We detected expression of Ig E in the serum,and measuring the thickness of the middle ear mucosa.In addition,tissue expression of interleukin(IL)-5 and aquaporin(AQP)5 in ME and nasal mucosa was assessed by immunohistochemical staining.Results:In control group C,the middle ear mucosa was ciliated epithelium,the nuclei were arranged neatly and evenly,and goblet cells were scattered sporadically,and only a small amount of connective tissue adhered to cartilage.In the model group,the mucosal epithelial cells of the middle ear increased and arranged disorderly,the goblet cells increased,and the epithelial cells metaplasia.The submucosa slightly thickened,blood vessels were dilated,fibroblasts increased,and eosinophils,lymphocytes and neutrophils infiltrated.The expression of Ig E in model group Ⅱ(182.24±7.69ng/ml)was significantly higher than that in group Ⅰ(33.35±8.80ng/ml)(P<0.05).The model group "nasal-Eustachian tube-middle ear mucosa" showed more consistent changes after HE staining.The thickness of the three middle ear tissues in each group was measured.The thickness of the mucosa near the Eustachian tube was model group Ⅰ(22.14±4.21um)and model groups Ⅱ(29.25±8.67um)are thicker than control group C(19.31±2.07um).The thickening of model group Ⅱ was more significant than that of controⅠ group C(P<0.05).The measurements of middle ear tympanic mucosa of model group Ⅱ(9.62±4.02um),model group Ⅰ(7.06±2.67um)are higher than that of control group C(5.61±0.78um).The thickening of the mucosa of model group Ⅱ was statistically different than that of group C(P<0.05).Tympanic membrane thickness measurement results of model group Ⅱ(9.31±3.03um),model group Ⅰ(7.33±2.5um),control group C(5.76±1.07um),there was no statistical difference(P>0.05).There was no significant difference in the expression of AQP5 in the middle ear mucosa of the three groups by immunohistochemistry(P>0.05).However,the expression of AQP5 in the nasal mucosa of the three groups was different,and the expression of AQP5 in model group Ⅱ was higher than that in group C,and the difference was statistically significant(P<0.05).The expression of IL-5 positive cells in the nasal mucosa and middle ear bone marrow cavity among the three groups are difference(P<0.05).The number of IL-5 positive cells expressing in model group Ⅱ was statistically significant higher than group C(P<0.05),while model group I had no statistical difference compared with model group Ⅱ and group C(P>0.05).Conclusion:The establishment of an animal model of allergy-related otitis media with effusion supports that allergy is one of the causes of the occurrence and development of otitis media with effusion.1.Allergens are sensitized through the upper respiratory tract,and the mucosa of the nose,eustachian tube,and middle ear have more consistent changes,which supports the theory of "middle ear-eustachian tube-upper respiratory tract combination";2.Under continuous antigen stimulation,the presence of allergy-related inflammatory mediators in the body causes irreversible changes to the structure of the mucosal tissue of the middle ear,from local inflammation of the middle ear to chronic otitis media;3.AQP5 was expressed in middle ear mucosal epithelial cells.Allergy may have no significant effect on the expression of AQP5.