Analysis of the level of non-specific and specific immunity parameters in saliva of children with osteogenesis imperfecta and study of relationships between selected proteins, disease symptoms and sociodemographic factors

Abstract

Introduction. Osteogenesis imperfecta is characterized by dental symptoms, including dentinogenesis imperfecta (DGI). Carious process can be modified by factors such as patient’s hygiene habits, diet, saliva and its components. Saliva’s elements of non-specific immunity with antibacterial and immunomodulatory action are hBD1, hBD2 defensins, cathelicidin LL-37, lysozyme and specific immunity – secretory immunoglobulin A. Aim. Analysis of levels of hBD1 and hBD2 defensins, cathelicidin LL-37, lysozyme and sIgA in saliva of children with osteogenesis imperfecta and in a comparative group of healthy children. Material and methods. In the years 2015-2018, 62 individuals with brittle bone disease were examined, samples of non-stimulated saliva were collected from 30 patients and from 30 subjects of the comparative group. Levels of the examined parameters were measured using ELISA immunoassays tests. Statistical analysis of laboratory test results was carried out. Statistically significant differences/relationships were established at the significance level of p < 0.05. Results. The concentration of the studied proteins in saliva did not differ significantly between the groups. There were statistically significant positive correlations between: age and sIgA concentration in saliva of the examined patients; age and concentration of hBD1 and hBD2 in saliva of children from the comparative group; age and sIgA concentration in saliva of patients from the study and comparative groups. For the comparative group, statistically significant differences in sIgA concentrations in saliva between girls and boys were observed. Conclusions. Laboratory test results of hBD1 and hBD2 defensins, cathelicidin LL-37, lysozyme and sIgA levels in saliva indicate that there is a need for further laboratory tests, which could explain the low levels of caries index in children with osteogenesis imperfecta. The increased levels of sIgA in saliva with growing age of the patients (with OI and healthy children) may indicate that specific immunity system matures with age or may reflect the impact of external environment on this parameter.