AB1039 LL-37, IL-36, GALECTIN-3 AND TLR-3 LEVELS IN IDIOPATHIC GRANULOMATOUS MASTITIS
Authors: U. Aydin, B. Oz, A. Karatas, M. Gur, R. Piskin Sagir, G. Artas, S. Aydin, S. S. Koca
Journal: Annals of the Rheumatic Diseases (2020)

Background: Idiopathic granulomatous mastitis (IGM) is a non-infectious inflammatory disorder of the breast characterized by non-caseous granulomas. It is a chronic granulomatous inflammatory disease frequently seen in young fertile women, the cause of which has not been clearly understood. Immunosuppressive agents and surgical interventions are used in the treatment. LL-37 is a cathelicidin-derived antimicrobial peptide with immunomodulatory properties that are effective in innate immunity. In addition, IL-36, galectin-3, TLR-3 are effective in autoimmunity with proinflammatory properties. Objectives: With this study, we aimed to investigate the potential alterations of LL-37, IL 36, Galectin 3 and TLR-3 levels in IGM. Methods: 35 female patients with biopsy-confirmed IGM and 35 healthy controls were included in the study. The serum samples of the subjects LL-37, IL 36, Galectin 3 and TLR-3 levels were studied using the Elisa method. While studying LL 37 and Galectin 3 levels in the tissue, samples of 10 patients who underwent mammoplasty for cosmetic reasons were used for the control group. Ten patients whose paraffin blocks were eligible for re-study were included in the study for tissue examinations. Based on the prevalence (0.1: &lt;%25,- 0.4:%26-50, 0.6:%51-75, 0.9:%76-100) and severity (0: no, +0.5: very little, +1: little, +2: medium, +3: severe) of immunoreactivity in staining, histoscore was created (histoscores = prevalence x severity). The data were evaluated using appropriate statistical analysis and p &lt;0.05 was considered statistically significant. Results: When the patient and control groups included in the study were compared, there was no significant difference in age. In serum samples, LL 37, IL 36, Galectin 3 and TLR 3 levels were statistically significantly lower in IGM group compared to the control group (p &lt;0.001 for each) (Table-1). In biopsy samples, LL 37 level was found to be significantly lower in IGM group compared to the control group (p &lt;0.001). However, no significant difference was detected in Galectin 3 levels in tissue studies (Table-2). Conclusion: In our study, we found that the levels of LL 37, IL 36, Galectin 3 and TLR 3 decreased in serum samples in IGM disease whose etiology was not clearly understood. In addition, we showed that in patients with IGM, LL 37 levels decreased at the tissue level. Studies have shown that in cases of severe sarcoidosis, LL 37 deficiency is reduced both in level and gene expression. So they thought, deficiency of cathelicidin LL 37 may impede resolution of inflammation in the tissue of patients with severe form disease. References: [1]Barna, Barbara P et al. “Alveolar macrophage cathelicidin deficiency in severe sarcoidosis.” Journal of innate immunity vol. 4,5-6 (2012): 569-78. [2]Al-Khaffaf, Bilal et al. “Idiopathic granulomatous mastitis: a 25-year experience.” Journal of the American College of Surgeons vol. 206,2 (2008): 269-73. Table 1. LL 37, IL 36, Galectin 3 and TLR 3 levels in serum samples IGM (N:35) CONTROL (N:35) P Age 35,92 ± 5,19 34,03 ± 3,81 0,08 LL 37 (ng/ml) 5,20 ± 5,48 40,05 ± 31,97 &lt;0,001 IL 36 (pg/ml) 294,74 ± 125,94 864,71 ± 442,39 &lt;0,001 Galectin 3 (ng/ml) 3,61 ± 3,16 15,53 ± 10,14 &lt;0,001 TLR 3 (pg/ml) 931,49 ± 443,86 4019,36 ± 2599,51 &lt;0,001 IGM: Idiopathic granulomatous mastitis Table 2. Evaluation of LL-37 and Galectin 3 levels with histoscores in biopsy samples IGM (N:10) CONTROL (N:10) P LL 37 0,006 ± 0,025 0,140 ± 0,516 &lt;0,001 Galectin 3 0,293 ± 0,201 0,400 ± 0,290 0,32 Disclosure of Interests: None declared