Osteoimmune Interaction and TH-1/TH-2 Ratio in Jawbone Marrow Defects: An Underestimated Association - Original Research.

Introduction: Osteoimmunology recognizes the relationship between bone cells and immune cells. Chronic osteoimmune dysregulation is present in bone marrow defects of the jaw (BMDJ) as fatty-degenerative osteonecrosis (FDOJ). In comparison to samples from healthy jaw bone, the cytokine analysis of samples of BMDJ/FDOJ from 128 patients showed downregulated TNF-α and IL-6 expression and the singular overexpression of the chemokine RANTES/CCL5. Aim and Objectives: This paper raises the question of whether the osteoimmune defects due to incomplete wound healing in BMDJ/FDOJ in 128 patients are related to dysregulation of the Th1/Th2 ratio and regulatory T cell (T-reg) expression in a control group of 197 BMDJ/FDOJ patients, each presenting with BMDJ/FJOD and one of seven different immune disorders. Material and Methods: In the control group, serum concentrations of the cytokines IFN-y and IL-4 were determined after stimulated cytokine release and displayed as Th1/Th2 ratios. Results: Data show a shift in Th2 in more than 80% (n = 167) of the control cohort of 197 chronically ill patients with concomitant BMDJ/FDOJ. In these 167 subjects, the Th1/Th2 ratio was <6.1 demonstrating impaired immune regulation. Forty-seven subjects or 30% showed not only a shift in Th2 but also excessive T-reg overactivation with levels of >1.900 pg/mL, indicating strongly downregulated immune activity. Discussion: BMDJ/FDOJ is characterized by a lack of Th1 cytokines and an excessive expression of RANTES/CCL5 and IL-1ra and, thus, the inversion of an acute inflammatory cytokine pattern. In contrast, abdominal fat contains a very high proportion of regulatory Th1 cells and produces an inflammatory immune response through the high overexpression of TNF-α and IL-6. The lack of Th1 activation in BMDJ/FDOJ areas inhibits normal wound healing and supports the persistence of BMDJ/FDOJ. Conclusion: The Th1/Th2 ratio requires greater consideration, especially with respect to wound healing following dental surgical interventions, such as jaw surgery, implantation and augmentation, to avoid the emergence of the osteoimmune situation that is characteristic of BMDJ/FDOJ.

Is preexisting inflamed jaw marrow a "hidden" co-morbidity affecting outcomes of COVID-19 infections? - Clinical comparative study.

Introduction: Exceedingly high levels of the chemokine CCL5/RANTES have been found in fatty degenerated osteonecrotic alveolar bone cavities (FDOJ) and aseptic ischemic osteolysis of the jaw (AIOJ) from toothless regions. Because CCL5/RANTES seems to have a prominent role in creating the COVID-19 "cytokine storm", some researchers have used the monoclonal antibody Leronlimab to block the CCR5 on inflammatory cells.Objective: Is preexisting FDOJ/AIOJ jaw marrow pathology a "hidden" co-morbidity affecting some COVID-19 infections? To what extent does the chronic CCL5/RANTES expression from preexisting FDOJ/AIOJ areas contribute to the progression of the acute cytokine storm in COVID-19 patients?Methods: Authors report on reducing the COVID-19 "cytokine storm" by treating infected patients through targeting the chemokine receptor 5 (CCR5) with Leronlimab and interrupting the activation of CCR5 by high CCL5/RANTES signaling, thus dysregulating the inflammatory phase of the viremia. Surgical removal of FDOJ/AIOJ lesions with high CCL5/RANTES from patients with inflammatory diseases may be classified as a co-morbid disease.Results: Both multiplex analysis of 249 FDOJ/AIOJ bone tissue samples as well as serum levels of CCL5/RANTES displayed exceedingly high levels in both specimens.Discussion: By the results the authors hypothesize that chronic CCL5/RANTES induction from FDOJ/AIOJ areas may sensitize CCR5 throughout the immune system, thus, enabling it to amplify its response when confronted with the virus. As conventional intraoral radiography does little to assess the quality of the alveolar bone, ultrasonography units are available to help dentists locate the FDOJ/AIOJ lesions in an office setting.Conclusion: The authors propose a new approach to containment of the COVID-19 cytokine storm by a prophylactic focus for future viral-related pandemics, which may be early surgical clean-up of CCL5/RANTES expression sources in the FDOJ/AIOJ areas, thus diminishing a possible pre-sensitization of CCR5. A more complete dental examination includes trans-alveolar ultrasono-graphy (TAU) for hidden FDOJ/AIOJ lesions.

Comparison of Cytokine RANTES/CCL5 Inflammation in Apical Periodontitis and in Jawbone Cavitations - Retrospective Clinical Study.

Background: Apical periodontitis (AP) is one of the most common endodontic diseases associated with osteo destructive cytokine production. The literature also reports cytokine studies in fatty degenerative osteonecrotic bone marrow defects (BMDJ/FDOJ) independent of AP. Objective: We compare the RANTES/CCL5 (R/C) chemokine production between AP and BMDJ/FDOJ. For both pathologies, the R/C expression was also compared to radiographic diagnosis in 2D-OPG, 3D-CBCT/DVT. Material and Methods: Postoperative samples were collected and divided in three different groups: HB (healthy jawbone) (n=19), APs (n=19), and BMDJ/FDOJ (n=7). The R/C expression was evaluated using multiplex analysis. In addition, two clinical cases from AP and BMDJ/FDOJ groups were randomly selected and radiographic diagnosis in 2D-OPG and 3D-CBCT/DVT was compared to TAU measurements and R/C expression in AP and in BMDJ/FDOJ. Results: BMDJ/FDOJ showed the highest R/C expression (2498.71 pg/mL), followed by AP (841.85 pg/mL) and HB (149.85 pg/mL) (AP vs BMDJ/FDOJ = p=0.01; AP vs HB = p=<0.01; BMDJ/FDOJ vs HB = p=<0.01). In both clinical cases, the radiographic findings depict the AP areas in OPG and CBCT/DVT, in contrast to the BMDJ/FDOJ areas. Conversely, the systemic immunological R/C expressions are threefold and fivefold excessive in both cases. Discussion: AP is recognized as a pathology requiring treatment, while the pathogenesis of BMDJ/FDOJ is controversially discussed in the literature, despite stronger potential systemic immunological effects (breast cancer (case 1) and multiple sclerosis (case 2)). The inadequate radiographic representation of reduced bone density in BMDJ/FDOJ areas could be a reason for this contradiction. Conclusion: The data presented provide the first quantitative analysis of R/C expression in AP and BMDJ/FDOJ. BMDJ/FDOJ showed high R/C expression than AP, besides the diagnostic through radiographs being extremely poor. To cover this imprecision, a radiation-free TAU device is available.

Osseointegration and osteoimmunology in implantology: assessment of the immune sustainability of dental implants using advanced sonographic diagnostics: research and case reports.

OBJECTIVE: Bone marrow defects of the jaw (BMDJ) surrounding dental implants, in combination with impaired bone-to-implant contact (BIC), are difficult to detect in X-rays. This study evaluated BMDJ surrounding titanium (Ti-Impl) and ceramic (Cer-Impl) dental implants and incomplete BIC using a new trans-alveolar ultrasonography device (TAU) with numerical scaling for BIC. METHODS: The titanium stimulation test (Ti-Stim) was used to detect immune overactivation in response to titanium. Bone density surrounding implants was measured using TAU. We also validated osteoimmune dysregulation. RESULTS: TAU values showed reduced BIC and decreased osseointegration for Ti-Impl. Moreover, TAU values in the Cer-Impl group were more than twice those in the Ti-Impl cohort. The multiplex analysis of C-C motif chemokine 5 (CCL5, also known as RANTES) expression revealed a 20-fold increase in BMDJ surrounding Ti-Impl. Higher levels of CCL5 inflammation were present in the positive Ti-Stim group. CONCLUSIONS: Our data indicate that Cer-Impl have an osteoimmune advantage over Ti-Impl. The key determinant for osteoimmune sustainability appears to be the absence of inflammation at the implant site. We therefore recommend the use of TAU to assess the implant site prior to implantation.