ABSTRACT
Memory T cells contribute to rapid viral clearance during re-infection, but the longevity and differentiation of SARS-CoV-2-specific memory T cells remain unclear. We conducted direct ex vivo assays to evaluate SARS-CoV-2-specific CD4+ and CD8+ T cell responses in COVID-19 convalescents up to 254 days post-symptom onset (DPSO). Here, we report that memory T cell responses were maintained during the study period. In particular, we observed sustained polyfunctionality and proliferation capacity of SARS-CoV-2-specific T cells. Among SARS-CoV-2-specific CD4+ and CD8+ T cells detected by activation-induced markers, the proportion of stem cell-like memory T (TSCM) cells increased, peaking at approximately 120 DPSO. Development of TSCM cells was confirmed by SARS-CoV-2-specific MHC-I multimer staining. Considering the self-renewal capacity and multipotency of TSCM cells, our data suggest that SARS-CoV-2-specific T cells are long-lasting after recovery from COVID-19. The current study provides insight for establishing an effective vaccination program and epidemiological measurement.
ABSTRACT
Calcium pyrophosphate (CPP) crystals can present as acute inflammatory arthritis which is known as an acute CPP crystal arthritis. Although monocytes/macrophages have been shown to play a role in the initiation of crystal-mediated inflammatory responses, differences in their phenotypes between acute CPP crystal arthritis and acute gouty arthritis have not yet been investigated. We examined the immunological characteristics of synovial monocytes/macrophages in patients with acute CPP crystal and acute gouty arthritis. CD14⁺CD3⁻CD19⁻CD56⁻ cell frequencies in synovial fluid mononuclear cells (SFMCs) were measured. Expression of pro- and anti-inflammatory cytokines and markers was determined. The SFMCs were dominated by a population of monocytes/macrophages in acute CPP crystal arthritis similar to that in acute gout. Synovial monocytes/macrophages showed the phenotypes of infiltrated monocytes as shown by expression of CD88, C-C chemokine receptor type 2, myeloid-related protein (MRP)8 and MRP14 but not proto-oncogene tyrosine-protein kinase MER. Comparatively, the CD14⁺ cells from patients with acute CPP crystal arthritis had similar high levels of IL-1β and TNF-α production but significantly lower expression of IL-10 and M2 marker (CD163). The monocytes/macrophages had the capacity to produce IL-8 in response to CPP crystals. Proinflammatory features were more dominant in monocytes/macrophages during acute CPP crystal arthritis than those during acute gouty arthritis.
Subject(s)
Humans , Arthritis , Arthritis, Gouty , Calcium Pyrophosphate , Calcium , Cytokines , Gout , Interleukin-10 , Interleukin-8 , Macrophages , Monocytes , Phenotype , Phosphotransferases , Proto-Oncogenes , Synovial FluidABSTRACT
The term odontoma, first introduced by Broca, was originally applied to all odontogenic tumors. Related to the clinical and histological differences, 2 groups of odontoma were defined: compound odontoma and complex odontoma. Complex odontoma is more common in the mandible than in the maxilla, usually occuring in the mandibular premolar-molar area. And this consists of small mass of irregularly arranged enamel, dentine, cementum, and connective tissue, but tooth-like structures are not found. In our case, 34 year old man was diagnosed as the complex odontoma of maxillary sinus by the physical exam, Panex, and C.T scan. We sectioned and removed it, and then confirmed the diagnosis histopathologically. Its uncommon location and size made us report that case and review the literature concerned.
Subject(s)
Adult , Humans , Connective Tissue , Dental Cementum , Dental Enamel , Dentin , Diagnosis , Mandible , Maxilla , Maxillary Sinus , Odontogenic Tumors , OdontomaABSTRACT
The term odontoma, first introduced by Broca, was originally applied to all odontogenic tumors. Related to the clinical and histological differences, 2 groups of odontoma were defined: compound odontoma and complex odontoma. Complex odontoma is more common in the mandible than in the maxilla, usually occuring in the mandibular premolar-molar area. And this consists of small mass of irregularly arranged enamel, dentine, cementum, and connective tissue, but tooth-like structures are not found. In our case, 34 year old man was diagnosed as the complex odontoma of maxillary sinus by the physical exam, Panex, and C.T scan. We sectioned and removed it, and then confirmed the diagnosis histopathologically. Its uncommon location and size made us report that case and review the literature concerned.
Subject(s)
Adult , Humans , Connective Tissue , Dental Cementum , Dental Enamel , Dentin , Diagnosis , Mandible , Maxilla , Maxillary Sinus , Odontogenic Tumors , OdontomaABSTRACT
The role of cultured bone marrow stromal cells (BMSCs) in peripheral nerve regeneration was examined using an established rabbit peroneal nerve regeneration model. A 15-mm peroneal nerve defect was bridged with a vein filled with BMSCs (1 x 10(6)), which had been embedded in collagen gel. On the contralateral side, the defect was bridged with a vein filled with collagen gel alone. When the regenerated tissue was examined 4, 8 and 12 weeks after grafting, the number and diameter of the myelinated fibers in the side with the BMSCs were significantly higher than in the control side without the BMSCs. This demonstrates the potential of using cultured BMSCs in peripheral nerve regeneration.
Subject(s)
Bone Marrow , Collagen , Mesenchymal Stem Cells , Myelin Sheath , Peripheral Nerves , Peroneal Nerve , Regeneration , Transplants , VeinsABSTRACT
OBJECTIVE: The aim of this study was to investigate whether dental implant exposure to the maxillary sinus cavity increases the risk of maxillary sinus complications. STUDY DESIGN: An implant was placed bilaterally in the maxillary sinus of eight adult female mongrel dogs in a way that it penetrated the bone and mucous membrane of the maxillary sinus floor to the extent of 2 mm, 4 mm, or 8 mm. The implants were left in place for six months. RESULTS: Radiographic and histologic examinations did not show any signs of pathologic findings in the maxillary sinus of the eight dogs. CONCLUSION: This study indicates that implant protrusion into the maxillary sinus cavity is not related to the development of sinus complications.
Subject(s)
Adult , Animals , Dogs , Female , Humans , Dental Implants , Maxillary Sinus , Mucous MembraneABSTRACT
Bone morphogenetic protein(BMP) and platelet-derived growth factor(PDGF) have been demonstrated tostimulate bone formation when applied locally in vivo. To explore whether or not the combined use of BMP and PDGF could have promotive effect and synergic interac- tion on bone formation in vivo, bone marrow mesenchymal stem cells were treated with BMP-2, PDGF-BB, or BMP-2 plus PDGF-BB, and then these cells were injected into the subcutaneous space on the dorsum of nude mice. The bone formation was evaluated after 12 weeks. Histomorphometric analysis demonstrated that the subcutaneous nodules formed in nude mice contained 25.3% newly formed bone in the BMP-2 treated cells, 14.4% newly formed bone in the PDGF-BB treated cells, and 8.9% newly formed bone in the BMP-2 plus PDGF-BB treated cells. The results showed that the combination of BMP-2 and PDGF-BB had neither a promotive effect nor synergic interact on bone formation in vivo.
Subject(s)
Animals , Mice , Bone Marrow , Bone Morphogenetic Proteins , Mesenchymal Stem Cells , Mice, Nude , Osteogenesis , Platelet-Derived Growth FactorABSTRACT
AIM: To assess the efficacy of cyanoacrylate adhesive in the management of large perforations of the maxillary sinus membrane during sinus lifts. MATERIAL AND METHODS: Eight rabbits were used in the study. Sinus membrane perforation(about 1.5cm) was repaired with cyanoacrylate adnesive on one side of the maxillary sinus and the opppsite side was used as a control. Histological evaluation was performed 4 weeks after the operation. RESULTS: Histological studies showed normal healing of the sinus membrane across the site of previous perforation and no evidence of inflammation. CONCLUSION: Our results support the clinical use of cynoacrylate adhesive for repairing sinus membrane perforation.
Subject(s)
Rabbits , Adhesives , Cyanoacrylates , Inflammation , Maxillary Sinus , MembranesABSTRACT
The main pathogenesis of osteoradionecrosis is the initial radiation cellular kill, plus the progressive tissue hypoxia owing to endarteritis, plus late expressions of lethal mutations in stromal cells. Its treatment comprised (1) avoidance of local physical, chemical & biological irritants, (2) wound irrigation, (3) antibiotics & analgesics, (4) superficial sequestrectomy, (5) hyperbaric oxygen therapy, (6) resection and reconstructive surgery, and (7) supportive therapy for systemic condition. Because of the cumulative effect of radiation therapy, it is important to manage the osteoradionecrosis conservatively & continuously, with emotional & physical support. The authors think that conservative care is more essential to the patient of poor systemic condition, than the aggressive resection & reconstructive surgery. We report two cases of pathologic fracture by osteoradionecrosis of mandible that were cared conservatively in the department of dentistry, Wonju Christian Hospital. The contents of treatment are continuous wound dressing, medications (antibiotics and analgesics) in acute infection, incision and drainage on new abscess, emotional support (stress management), proper nutritional and physical supports (exercise and physical therapy). The prognosis of continuous conservative care is relatively favorable.