Salvage of Ear Framework Exposure Following Autologous Microtia Reconstruction: Repair Strategy for Each Location of Exposure.

One of the most common complications of total auricular reconstruction is exposure of the ear framework. Various reconstruction methods have been reported depending on the location and size of exposed cartilage. This report describes a safe reconstruction method for each exposed part of the grafted ear framework. From January 2019 to August 2021, 2 cases (4 areas) of framework exposure were observed following autologous microtia reconstruction. The first case developed 2 small areas of skin necrosis on the anterior helix and lower antihelix to concha. The former was reconstructed with a temporal fascia flap and the latter with a local transposition flap. The second case also developed 2 small areas of skin necrosis on the posterior helix and lower antihelix to concha. The former was sutured directly and the latter with a local transposition flap. However, both wounds recurred due to flap necrosis and the cartilage was exposed again. The 3rd operation was performed by covering both wounds with a posterior auricular turnover flap and skin graft. In both cases, the exposed framework was completely covered with the flaps, and the reconstructed ears showed well-defined convolutions. Covering exposed cartilage with a local flap with a random pattern of blood circulation is convenient because no additional skin grafts are required. However, the blood circulation of the flaps is inadequate when an elongated flap is required; consequently, flap necrosis may occur. On the other hand, a temporal fascia flap and posterior auricular flap, which have axillary pattern blood circulation, are considered to be safer. We believe that it is safe to use a temporal fascia flap for cartilage exposure in the upper half of the auricle, and a posterior auricular turnover flap for the lower half.

Functional Analysis of Foxp3 and Its Mutants by Retroviral Transduction of Murine Primary CD4+ T Cells.

The transcription factor Foxp3/FOXP3 orchestrates regulatory T (Treg) cell development and function by interacting with numerous target genes and partner proteins. Functional analysis of naturally occurring or engineered Foxp3/FOXP3 mutations has provided important insights into how the complex Foxp3/FOXP3-centered molecular network operates. Here, we describe detailed protocols for retroviral transduction of murine primary conventional CD4+ T cells to determine the impacts of Foxp3 mutations on the Treg-cell-like phenotype and function conferred by Foxp3.

The adaptability of regulatory T cells and Foxp3.

Regulatory T (Treg) cells that express the lineage-defining transcription factor Foxp3 play a pivotal role in establishing and maintaining immune and tissue homeostasis. Foxp3 serves as a highly connected 'hub', interacting with numerous genomic sites and partner proteins, in the molecular network that orchestrates multiple facets of Treg cell differentiation and function. Treg cells are distributed throughout the body from lymphoid tissues to most non-lymphoid tissues, where they exert anti-inflammatory and protective functions appropriate for the tissue and immune environment. They are thus capable of adapting to diverse and changing environments by dynamically integrating extrinsic cues with the intrinsic molecular network. In this review, we discuss recent advances in our understanding of the cell-intrinsic and -extrinsic mechanisms underlying the adaptability of Treg cells and we propose a crucial role for the Foxp3-centered molecular network, which operates in a multimodal and adaptive manner in response to environmental signals.

Utility of Preoperative Multidetector-Row Computed Tomographic Angiography after Sublingual Nitroglycerin with Three-Dimensional Reconstruction in Planning of the Anterolateral Thigh Flap.

The utility of nitroglycerin is well established in coronary angiography but less so in other surgical fields. In this study, the authors investigated the utility of preoperative computed tomographic angiography after sublingual nitroglycerin followed by three-dimensional visualization for selecting suitable perforators in planning the free anterolateral thigh flap. The authors performed preoperative computed tomographic angiography following sublingual nitroglycerin (after screening for contraindications) in patients for whom reconstructive surgery with the free anterolateral thigh flap was planned. Data were reconstructed three-dimensionally, mapping location and course of source arteries and perforators. Suitable perforators were selected, and flap design was planned. The characteristics of perforators were analyzed statistically. Of 14 patients for whom surgery was planned, two had contraindications to nitroglycerin and underwent computed tomographic angiography alone. Nitroglycerin allowed for the visualization of more peripheral branches. The Hounsfield units at the deep fascia of perforators selected for surgery were significantly higher than for those not selected (p = 0.003). The distance from the intermuscular septum to the selected perforators was significantly shorter than the distance to nonselected perforators (p = 0.017). There were no adverse events, and all flaps survived. Sublingual nitroglycerin before computed tomographic angiography was safe and increased the visibility of perforators, enabling preoperative planning of flap design based on the three-dimensionally-reconstructed image. The authors highly recommend this procedure. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Diagnostic, IV.

Defective induction of the proteasome associated with T-cell receptor signaling underlies T-cell senescence.

The proteasome degradation machinery is essential for a variety of cellular processes including senescence and T-cell immunity. Decreased proteasome activity is associated with the aging process; however, the regulation of the proteasome in CD4+ T cells in relation to aging is unclear. Here, we show that defects in the induction of the proteasome in CD4+ T cells upon T-cell receptor (TCR) stimulation underlie T-cell senescence. Proteasome dysfunction promotes senescence-associated phenotypes, including defective proliferation, cytokine production and increased levels of PD-1+ CD44High CD4+ T cells. Proteasome induction by TCR signaling via MEK-, IKK- and calcineurin-dependent pathways is attenuated with age and decreased in PD-1+ CD44High CD4+ T cells, the proportion of which increases with age. Our results indicate that defective induction of the proteasome is a hallmark of CD4+ T-cell senescence.

Analyses of a Mutant Foxp3 Allele Reveal BATF as a Critical Transcription Factor in the Differentiation and Accumulation of Tissue Regulatory T Cells.

Foxp3 controls the development and function of regulatory T (Treg) cells, but it remains elusive how Foxp3 functions in vivo. Here, we established mouse models harboring three unique missense Foxp3 mutations that were identified in patients with the autoimmune disease IPEX. The I363V and R397W mutations were loss-of-function mutations, causing multi-organ inflammation by globally compromising Treg cell physiology. By contrast, the A384T mutation induced a distinctive tissue-restricted inflammation by specifically impairing the ability of Treg cells to compete with pathogenic T cells in certain non-lymphoid tissues. Mechanistically, repressed BATF expression contributed to these A384T effects. At the molecular level, the A384T mutation altered Foxp3 interactions with its specific target genes including Batf by broadening its DNA-binding specificity. Our findings identify BATF as a critical regulator of tissue Treg cells and suggest that sequence-specific perturbations of Foxp3-DNA interactions can influence specific facets of Treg cell physiology and the immunopathologies they regulate.

Novel Application of Cultured Epithelial Autografts (CEA) with Expanded Mesh Skin Grafting Over an Artificial Dermis or Dermal Wound Bed Preparation.

Cultured epithelial autografts (CEA) with highly expanded mesh skin grafts were used for extensive adult burns covering more than 30% of the total body surface area. A prospective study on eight patients assessed subjective and objective findings up to a 12-month follow-up. The results of wound healing for over 1:6 mesh plus CEA, gap 1:6 mesh plus CEA, and 1:3 mesh were compared at 3, 6, and 12 months using extensibility, viscoelasticity, color, and transepidermal water loss by a generalized estimating equation (GEE) or generalized linear mixed model (GLMM). No significant differences were observed among the paired treatments at any time point. At 6 and 12 months, over 1:6 mesh plus CEA achieved significantly better expert evaluation scores by the Vancouver and Manchester Scar Scales (p < 0.01). Extended skin grafting plus CEA minimizes donor resources and the quality of scars is equal or similar to that with conventional low extended mesh slit-thickness skin grafting such as 1:3 mesh. A longitudinal analysis of scars may further clarify the molecular changes of scar formation and pathogenesis.

A unique dermal dendritic cell subset that skews the immune response toward Th2.

Dendritic cell (DC) subsets in the skin and draining lymph nodes (LNs) are likely to elicit distinct immune response types. In skin and skin-draining LNs, a dermal DC subset expressing macrophage galactose-type C-type lectin 2 (MGL2/CD301b) was found distinct from migratory Langerhans cells (LCs) or CD103(+) dermal DCs (dDCs). Lower expression levels of Th1-promoting and/or cross-presentation-related molecules were suggested by the transcriptome analysis and verified by the quantitative real-time PCR analysis in MGL2(+) dDCs than in CD103(+) dDCs. Transfer of MGL2(+) dDCs but not CD103(+) dDCs from FITC-sensitized mice induced a Th2-type immune response in vivo in a model of contact hypersensitivity. Targeting MGL2(+) dDCs with a rat monoclonal antibody against MGL2 efficiently induced a humoral immune response with Th2-type properties, as determined by the antibody subclass. We propose that the properties of MGL2(+) dDCs, are complementary to those of CD103(+) dDCs and skew the immune response toward a Th2-type response.

Local effects of regulatory T cells in MUC1 transgenic mice potentiate growth of MUC1 expressing tumor cells in vivo.

MUC1 transgenic (MUC1.Tg) mice have widely been used as model recipients of cancer immunotherapy with MUC1. Although MUC1.Tg mice have previously been shown to be immunologically tolerant to MUC1, the involvement of regulatory T (Treg) cells in this phenotype remains unclear. Here, we showed that numbers of Treg cells in MUC1-expressing tumors were greater in MUC1.Tg mice than in control C57BL/6 (B6) mice, and that the growth of tumor cells expressing MUC1, but not that of control cells, in MUC1. Tg mice was faster than in B6 mice. The MUC1.Tg mice appeared to develop MUC1-specific peripheral tolerance, as transferred MUC1-specific T cells were unable to function in MUC1.Tg mice but were functional in control B6 mice. The suppressive function of CD4(+)CD25(high) cells from MUC1.Tg mice was more potent than that of cells from control B6 mice when Treg cell activity against MUC1-specific T cells was compared in vitro. Therefore, the enhanced growth of MUC1-expressing tumor cells in MUC1.Tg mice is likely due to the presence of MUC1-specific Treg cells.

Conditional ablation of CD205+ conventional dendritic cells impacts the regulation of T-cell immunity and homeostasis in vivo.

Dendritic cells (DCs) are composed of multiple subsets that play a dual role in inducing immunity and tolerance. However, it is unclear how CD205(+) conventional DCs (cDCs) control immune responses in vivo. Here we generated knock-in mice with the selective conditional ablation of CD205(+) cDCs. CD205(+) cDCs contributed to antigen-specific priming of CD4(+) T cells under steady-state conditions, whereas they were dispensable for antigen-specific CD4(+) T-cell responses under inflammatory conditions. In contrast, CD205(+) cDCs were required for antigen-specific priming of CD8(+) T cells to generate cytotoxic T lymphocytes (CTLs) mediated through cross-presentation. Although CD205(+) cDCs were involved in the thymic generation of CD4(+) regulatory T cells (Tregs), they maintained the homeostasis of CD4(+) Tregs and CD4(+) effector T cells in peripheral and mucosal tissues. On the other hand, CD205(+) cDCs were involved in the inflammation triggered by Toll-like receptor ligand as well as bacterial and viral infections. Upon microbial infections, CD205(+) cDCs contributed to the cross-priming of CD8(+) T cells for generating antimicrobial CTLs to efficiently eliminate pathogens, whereas they suppressed antimicrobial CD4(+) T-cell responses. Thus, these findings reveal a critical role for CD205(+) cDCs in the regulation of T-cell immunity and homeostasis in vivo.

A consecutive case review of orbital blowout fractures and recommendations for comprehensive management.

BACKGROUND: The orbital blowout fracture is a common facial injury, but full consensus has not been reached regarding its optimal management. The authors retrospectively explored consecutive cases of blowout fractures and proposed new recommendations for treatment. METHODS: Two hundred eight newly registered patients were selected from the database of Nagasaki University Hospital over the past 5 years. One hundred nine patients in the authors' department were then reviewed regarding computed tomographic classification of fracture types, preoperative complaints, and outcomes. RESULTS: Of the 208 patients reviewed, 43 underwent surgical repair: 37 for diplopia and 14 for enophthalmos, including eight patients who were treated for both conditions. Regarding floor fractures, the punched-out type fracture was the most common, but the burst type was associated with the highest likelihood of undergoing surgery. For medial wall fractures, the punched-out type dominated, but the overall operative incidence was lower than that observed for the floor fractures. For diplopia, more than half of the operations were performed within 2 weeks, but only two cases were performed within 3 days. For enophthalmos, over 60 percent of operations were carried out after 1 month. Two cases, later discovered to involve muscle strangulation, continued to demonstrate residual diplopia in ordinary use, and two patients continued to show enophthalmos. However, overall outcomes were considered satisfactory. CONCLUSIONS: If computed tomographic findings disclose a linear fracture with muscular strangulation, urgent surgery must be performed. However, for linear fractures without impaction of the muscle, or punched-out or burst type fractures, close observation for days may be appropriate. In addition, surgical intervention can be performed electively when diplopia persists for several days of observation.

Total lower eyelid reconstruction with a prefabricated flap using auricular cartilage.

INTRODUCTION: Various methods have been reported for reconstructing the lower eyelid, but there is still the problem of creating a deep fornix and a supportive eyelid for housing an artificial eye. CASE REPORT: A new prefabricated flap was developed using auricular cartilage and the lateral femoral circumflex vessels as vascular pedicles. This was applied in a 64-year-old male patient with total lower eyelid loss following an extended maxillectomy for tumour. CONCLUSION: The prefabricated flap described here showed more flexibility and a longer vascular pedicle, thus improving the applications for use in patients with limited recipient vessels yet without major sacrifice or deformity in the donor area.

Malignant transformation of ameloblastic fibroma to ameloblastic fibrosarcoma: case report and review of the literature.

INTRODUCTION: Ameloblastic fibrosarcoma is a rare malignant odontogenic tumour and is regarded as the malignant counterpart of the ameloblastic fibroma. The epithelial component remains benign, but the mesenchymal component becomes malignant. The diagnosis is made by histopathology. PATIENT: The case of a 26-year-old man who underwent curettage of an ameloblastic fibroma and died of an ameloblastic fibrosarcoma is presented, and the course of malignant transformation is analysed retrospectively. CONCLUSION: One-third of ameloblastic fibrosarcoma cases seem to have developed from recurrent ameloblastic fibromas. Knowledge of the malignant potential in the mesenchymal spindle cells of ameloblastic fibroma will assist in determining the management of these benign tumours, and may prevent malignant transformation to ameloblastic fibrosarcoma.

Microsurgical dermal-fat retransfer for progressive hemifacial atrophy.

Although the etiology of progressive hemifacial atrophy, Romberg's disease, is still unknown, it typically manifests during emotionally salient times, such as the period before the age of 20 years. It involves not only the subcutaneous tissue and skin but also the muscles and osteocartilaginous framework later. Treatment for the atrophy is, in general, recommended after progression of the disease ceases; otherwise, many augmentations will be required after re-atrophy. However, it has recently been reported that well-vascularized tissue might maintain its volume even in the progressive stage, and that progression might be interrupted by vascularized tissue transplantation. The authors report a case reconstructed with free vascularized dermal-fat re-transfer 13 years after a first reconstruction with free-flap transfer, because the primarily over-corrected region had gradually atrophied and the patient desired further treatment. Even though disease progression could not be completely controlled in this case, free vascularized tissue transfer should be considered for mentally fragile young patients, because the free flap is the best among the procedures for Romberg's disease for maintaining volume.