Intradermal lipopolysaccharide challenge as an acute in vivo inflammatory model in healthy volunteers.

AIMS: Whereas intravenous administration of Toll-like receptor 4 ligand lipopolysaccharide (LPS) to human volunteers is frequently used in clinical pharmacology studies, systemic use of LPS has practical limitations. We aimed to characterize the intradermal LPS response in healthy volunteers, and as such qualify the method as local inflammation model for clinical pharmacology studies. METHODS: Eighteen healthy male volunteers received 2 or 4 intradermal 5 ng LPS injections and 1 saline injection on the forearms. The LPS response was evaluated by noninvasive (perfusion, skin temperature and erythema) and invasive assessments (cellular and cytokine responses) in skin biopsy and blister exudate. RESULTS: LPS elicited a visible response and returned to baseline at 48 hours. Erythema, perfusion and temperature were statistically significant (P < .0001) over a 24-hour time course compared to saline. The protein response was dominated by an acute interleukin (IL)-6, IL-8 and tumour necrosis factor response followed by IL-1ß, IL-10 and interferon-γ. The cellular response consisted of an acute neutrophil influx followed by different monocyte subsets and dendritic cells. DISCUSSION: Intradermal LPS administration in humans causes an acute, localized and transient inflammatory reaction that is well-tolerated by healthy volunteers. This may be a valuable inflammation model for evaluating the pharmacological activity of anti-inflammatory investigational compounds in proof of pharmacology studies.

Potent anti-inflammatory effects of an H2 S-releasing naproxen (ATB-346) in a human model of inflammation.

ATB-346 is a hydrogen sulfide-releasing non-steroidal anti-inflammatory drug (H2 S-NSAID) derived from naproxen, which in preclinical studies has been shown to have markedly reduced gastrointestinal adverse effects. However, its anti-inflammatory properties in humans compared to naproxen are yet to be confirmed. To test this, we used a dermal model of acute inflammation in healthy, human volunteers, triggered by ultraviolet-killed Escherichia coli. This robust model allows quantification of the cardinal signs of inflammation along with cellular and humoral factors accumulating within the inflamed skin. ATB-346 was non-inferior to naproxen in terms of its inhibition of cyclooxygenase activity as well as pain and tenderness. ATB-346 significantly inhibited neutrophil infiltration at the site of inflammation at 4 h, compared to untreated controls. Subjects treated with ATB-346 also experienced significantly reduced pain and tenderness compared to healthy controls. Furthermore, both classical and intermediate monocyte subsets infiltrating the site of inflammation at 48 h expressed significantly lower levels of CD14 compared to untreated controls, demonstrating a shift toward an anti-inflammatory phenotype. Collectively, we have shown for the first time in humans that ATB-346 is potently anti-inflammatory and propose that ATB-346 represents the next generation of H2 S-NSAIDs, as a viable alternative to conventional NSAIDs, with reduced adverse effects profile.

Monocytes, macrophages, dendritic cells and neutrophils: an update on lifespan kinetics in health and disease.

Phagocytes form a family of immune cells that play a crucial role in tissue maintenance and help orchestrate the immune response. This family of cells can be separated by their nuclear morphology into mononuclear and polymorphonuclear phagocytes. The generation of these cells in the bone marrow, to the blood and finally into tissues is a tightly regulated process. Ensuring the adequate production of these cells and their timely removal is key for both the initiation and resolution of inflammation. Insight into the kinetic profiles of innate myeloid cells during steady state and pathology will permit the rational development of therapies to boost the production of these cells in times of need or reduce them when detrimental.

Variations in the Phagosomal Environment of Human Neutrophils and Mononuclear Phagocyte Subsets.

The phagosome microenvironment maintains enzyme activity and function. Here we compared the phagosomal pH of human neutrophils, monocytes, dendritic cells (DC), and monocyte-derived cells. An unexpected observation was the striking difference in phagosomal environment between the three monocytes subsets. Classical monocytes and neutrophils exhibited alkaline phagosomes, yet non-classical monocytes had more acidic phagosomes, while intermediate monocytes had a phenotype in-between. We next investigated the differences between primary naïve DC vs. in vitro monocyte-derived DC (MoDC) and established that both these cells had acidic phagosomal environments. Across all phagocytes, alkalinization was dependent upon the activity of the NADPH oxidase activity, demonstrated by the absence of NADPH oxidase from a patient with chronic granulomatous disease (CGD) or the use of a pharmacological inhibitor, diphenylene iodonium (DPI). Interestingly, MoDC stimulated with bacterial lipopolysaccharide had increased phagosomal pH. Overall, the increase in alkalinity within the phagosome was associated with increased oxidase activity. These data highlight the heterogeneous nature and potential function of phagocytic vacuoles within the family of mononuclear phagocytes.

A Subset of Type I Conventional Dendritic Cells Controls Cutaneous Bacterial Infections through VEGFα-Mediated Recruitment of Neutrophils.

Skin conventional dendritic cells (cDCs) exist as two distinct subsets, cDC1s and cDC2s, which maintain the balance of immunity to pathogens and tolerance to self and microbiota. Here, we examined the roles of dermal cDC1s and cDC2s during bacterial infection, notably Propionibacterium acnes (P. acnes). cDC1s, but not cDC2s, regulated the magnitude of the immune response to P. acnes in the murine dermis by controlling neutrophil recruitment to the inflamed site and survival and function therein. Single-cell mRNA sequencing revealed that this regulation relied on secretion of the cytokine vascular endothelial growth factor α (VEGF-α) by a minor subset of activated EpCAM+CD59+Ly-6D+ cDC1s. Neutrophil recruitment by dermal cDC1s was also observed during S. aureus, bacillus Calmette-Guérin (BCG), or E. coli infection, as well as in a model of bacterial insult in human skin. Thus, skin cDC1s are essential regulators of the innate response in cutaneous immunity and have roles beyond classical antigen presentation.

Fine needle aspirates comprehensively sample intrahepatic immunity.

OBJECTIVE: In order to refine new therapeutic strategies in the pipeline for HBV cure, evaluation of virological and immunological changes compartmentalised at the site of infection will be required. We therefore investigated if liver fine needle aspirates (FNAs) could comprehensively sample the local immune landscape in parallel with viable hepatocytes. DESIGN: Matched blood, liver biopsy and FNAs from 28 patients with HBV and 15 without viral infection were analysed using 16-colour multiparameter flow cytometry. RESULTS: The proportion of CD4 T, CD8 T, Mucosal Associated Invariant T cell (MAIT), Natural Killer (NK) and B cells identified by FNA correlated with that in liver biopsies from the same donors. Populations of Programmed Death-1 (PD-1)hiCD39hi tissue-resident memory CD8 T cells (CD69+CD103+) and liver-resident NK cells (CXCR6+T-betloEomeshi), were identified by both FNA and liver biopsy, and not seen in the blood. Crucially, HBV-specific T cells could be identified by FNAs at similar frequencies to biopsies and enriched compared with blood. FNAs could simultaneously identify populations of myeloid cells and live hepatocytes expressing albumin, Scavenger Receptor class B type 1 (SR-B1), Programmed Death-Ligand 1 (PD-L1), whereas hepatocytes were poorly viable after the processing required for liver biopsies. CONCLUSION: We demonstrate for the first time that FNAs identify a range of intrahepatic immune cells including locally resident sentinel HBV-specific T cells and NK cells, together with PD-L1-expressing hepatocytes. In addition, we provide a scoring tool to estimate the extent to which an individual FNA has reliably sampled intrahepatic populations rather than contaminating blood. The broad profiling achieved by this less invasive, rapid technique makes it suitable for longitudinal monitoring of the liver to optimise new therapies for HBV.

The fate and lifespan of human monocyte subsets in steady state and systemic inflammation.

In humans, the monocyte pool comprises three subsets (classical, intermediate, and nonclassical) that circulate in dynamic equilibrium. The kinetics underlying their generation, differentiation, and disappearance are critical to understanding both steady-state homeostasis and inflammatory responses. Here, using human in vivo deuterium labeling, we demonstrate that classical monocytes emerge first from marrow, after a postmitotic interval of 1.6 d, and circulate for a day. Subsequent labeling of intermediate and nonclassical monocytes is consistent with a model of sequential transition. Intermediate and nonclassical monocytes have longer circulating lifespans (∼4 and ∼7 d, respectively). In a human experimental endotoxemia model, a transient but profound monocytopenia was observed; restoration of circulating monocytes was achieved by the early release of classical monocytes from bone marrow. The sequence of repopulation recapitulated the order of maturation in healthy homeostasis. This developmental relationship between monocyte subsets was verified by fate mapping grafted human classical monocytes into humanized mice, which were able to differentiate sequentially into intermediate and nonclassical cells.

Directed balloon cytology of the esophagus: A novel device for obtaining circumferential cytologic sampling.

OBJECTIVE: Current methods of obtaining esophageal cytology include brush biopsy and blind balloon sampling, among others. These methods can be time-consuming if performed in accordance with acknowledged standards. Further, exact site localization can prove to be difficult. We describe a novel device for esophageal sampling using an esophageal balloon with debriding strips contained within the pleats of the balloon. Inflation brings the latter in contact with the surface to be sampled. Cell capture was compared with the commonly used brush technique in a pig model. METHODS: Separate balloon and standard brush cytology samples were collected from a pig model. Smear and cell pellet preparations were compared regarding cell density and total volume. RESULTS: Adequate samples were obtained with both the brush and balloon. On the cell smear preparations, the cell density was greater when obtained with balloon sampling. Further, the cell pellet volume was significantly greater with the latter as well. The intact morphology of individual rafts of squamous epithelial cells also was comparable between the two methods. In addition, the balloon provided precise mapping of the cytology sites in contrast to the standard brush technique. CONCLUSION: We present an innovative new balloon technology for esophageal sampling, which demonstrated a decreased sampling time interval, precise mapping, and increased cellular volume when compared to a commonly used brush technique. LEVEL OF EVIDENCE: NA. Laryngoscope, 127:1032-1035, 2017.

Laryngology in Art: The Portrait of Dr Wilhelm Mayer-Hermann.

Otto Dix's portrait of the laryngologist Dr Wilhelm Mayer-Hermann represents a shining example of Neue Sachlichkeit, or New Objectivity, offering a return to unsentimental reality and a focus on the objective world, as opposed to the more abstract and idealistic tendencies of expressionism. However, precious little is known about the subject of the portrait. This article examines the portrait and attempts to shed light on the life and career of the Dr Wilhelm Mayer-Hermann.

Subglottic Squamous Cell Carcinoma: A Population-Based Study of 889 Cases.

OBJECTIVE: Subglottic squamous cell carcinoma (SCCa) is a rare malignancy representing <5% of all laryngeal cancers. Patients often present with late-stage disease, and survival outcomes are reportedly worse than those for SCCa in other regions of the larynx. STUDY DESIGN: Analysis of a population-based tumor registry. SETTING: Academic medical center. SUBJECTS AND METHODS: The US National Cancer Institute's Surveillance, Epidemiology, and End Results database was queried for cases of subglottic SCCa from 1973 to 2011 (889 cases). Resulting data were analyzed, including patient demographics, therapeutic measures, and survival outcomes. RESULTS: Subglottic SCCa most frequently occurred in the fifth to seventh decade of life, with a mean age at diagnosis of 65.7 ± 11.3 years. There was a strong male predilection, with a male:female ratio of 3.83:1. Most patients were stage III and IV (64.4%) per the American Joint Committee on Cancer. The most common treatment modality was a combination of radiotherapy and surgery (38.8%), followed by radiotherapy alone (33.9%), and surgery alone (17.0%). Overall 5-year disease-specific survival rate was 53.7%. When stratified by treatment modality, 5-year disease-specific survival was 62.4% for surgery alone, 56.7% for radiotherapy alone, and 55.1% for surgery with adjuvant radiotherapy (P = .3892). CONCLUSION: This study represents the largest cohort of subglottic SCCa. It shows a strong predilection for men in the US population. Surgery with adjuvant radiotherapy was the most commonly employed treatment modality. No statistically significant differences were observed in 5-year DSS by treatment modality.

Endoscopic palliative decompression of the cavernous sinus in a rare case of a metastatic renal cell carcinoma to the clivus.

We present a rare case of acute cavernous sinus syndrome due to a renal cell carcinoma metastasis to the clivus. This case highlights the role of palliative endoscopic endonasal decompression of the cavernous sinus to relieve cranial neuropathies, obtain tissue diagnosis, and for cytoreduction in preparation for additional adjuvant therapy.

Nodular lymphocyte predominant hodgkin lymphoma: biology, diagnosis and treatment.

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is an uncommon variant of classical Hodgkin lymphoma. It is characterized histologically by presence of lymphohistiocytic cells which have B-cell phenotype, are positive for CD19, CD20, CD45, CD79a, BOB.1, Oct.2, and negative for CD15 and CD30. Patients often present with early stage of disease and do not have classical B symptoms. The clinical behavior appears to mimic that of an indolent non-Hodgkin lymphoma more than that of classical Hodgkin disease. The purpose of the present report is to define the biology of NLPHL, review its clinical presentation, and summarize the available clinical data regarding treatment.

Laryngeal chondrosarcoma: a population-based analysis.

OBJECTIVES/HYPOTHESIS: Laryngeal chondrosarcoma (LC) is a rare entity, reportedly comprising less than 1% of all laryngeal tumors. Consequently, the incidence and survival of patients with this slow-growing tumor has been difficult to study. Our objective was to evaluate incidence, organized by patient demographics, as well as long-term survival trends of this malignancy using a population-based database. STUDY DESIGN: Retrospective analysis of the United States National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) registry. METHODS: The SEER database was searched for patients diagnosed with LC between 1973 and 2010. Data analyzed included patient demographics, incidence, treatment modality, and survival. RESULTS: One-hundred and forty-three cases were identified, representing 0.2% of all laryngeal tumors. Median age at diagnosis was 61.7 years. Men and women constituted 76.2% and 23.8% of patients, respectively. Tumors were locally invasive with 37.7% T4 disease and infrequent regional and distant metastases. The 1-year, 5-year, and 10-year disease-specific survival for LC was 96.5%, 88.6%, and 84.8%, respectively, compared to 88.3%, 68.2%, and 59.3%, respectively for patients with all other laryngeal tumors (P values < 0.01). Relative survival was 94.9% at 1 year, 88.5% at 5 years, and 88.4% at 10 years. CONCLUSIONS: This analysis represents the largest LC study sample to date, allowing for evaluation of incidence and long-term survival. LC occurs infrequently, is locally invasive, but only rarely metastasizes. Prognosis for LC is significantly better than for other laryngeal malignancies.

Celebrating the golden anniversary of anterior skull base surgery: reflections on the past 50 years and its historical evolution.

With its inception nearly half a century ago through the pioneering work of Dandy, McLean, and Smith, anterior skull base (ASB) surgery is a relatively young discipline. It became a distinct entity in 1963 when Ketcham popularized the combined transcranial transfacial approach for en bloc resection of tumors of the paranasal sinuses extending into the anterior cranial fossa. However, because these procedures resulted in major morbidities and mortalities, alternative modes of treatment were sought. Since the 1970s, the introduction and promotion of the surgical endoscope by Messerklinger, Stammberger, and Kennedy, commenced the era of endoscopic sinus surgery. Thaler and colleagues described the utility of the endoscope for ASB surgery at the turn of the century. This allowed direct visualization and safer, more accurate removal of tumors. In 2001, Casiano reported the first purely endoscopic endonasal ASB resection, a novel technique that has been adopted by major skull base centers. The success of ASB surgery can be attributed to both the development of the skull base team as well as improvements in surgical techniques, instrumentation, and visualization technology. In this article, we review the historical evolution of ASB surgery as we approach the 50th anniversary since its recognition as a distinct entity.

Early harvesting of the vascularized pedicled nasoseptal flap during endoscopic skull base surgery.

PURPOSE: The vascularized pedicled nasoseptal flap (PNSF) represents a successful option for reconstruction of large skull base defects after expanded endoscopic endonasal approaches (EEA). This vascularized flap can be harvested early or late in the operation depending on the anticipation of high-flow CSF leaks. Each harvesting technique (early vs. late) is associated with different advantages and disadvantages. In this study, we evaluate our experience with early harvesting of the PNSF for repair of large skull base defects after EEA. METHODS: A retrospective review was performed at a tertiary care medical center on patients who underwent early PNSF harvesting during reconstruction of intraoperative high-flow CSF leaks after EEA between December 2008 and March 2012. Demographic data, repair materials, surgical approach, and incidence of PNSF usage were collected. RESULTS: Eighty-seven patients meeting the inclusion criteria were identified. In 86 procedures (98.9%), the PNSF harvested at the beginning of the operation was used. In 1 case (1.1%), the PNSF was not used because a high-flow intraoperative CSF leak was not encountered. This patient had recurrence of intradural disease 8months later, and the previously elevated PNSF was subsequent used after tumor resection. CONCLUSION: Based on our data, a high-flow CSF leak and need for a PNSF can be accurately anticipated in patients undergoing EEA for skull base lesions. Because of the advantages of early harvesting of the PNSF and the high preoperative predictive value of CSF leak anticipations, this technique represents a feasible harvesting practice for EEA surgeries.

Systemic approaches for multifocal bronchioloalveolar carcinoma: is there an appropriate target?

Bronchioloalveolar carcinoma (BAC) is a subset of pulmonary adenocarcinoma characterized by distinct and unique pathological, molecular, radiographic, and clinical features. While the incidence of pure BAC is rare, comprising only 1% to 4% of non-small-cell lung cancer (NSCLC), mixed subtypes (including BAC with focal invasion and adenocarcinoma with BAC features) represent as much as 20% of adenocarcinomas--and that figure may be increasing. Despite the longstanding recognition of this entity, there is no established treatment paradigm for patients with multifocal BAC, resulting in competing approaches and treatment controversies. Current options for multifocal BAC include both surgery and systemic therapies. Unfortunately, prospective data on systemic approaches are limited by study design and small patient numbers; there are only seven phase II studies involving four therapies. This article evaluates key characteristics of BAC, including the current understanding of histopathology and tumor biology. In addition, it comprehensively reviews the systemic phase II studies in an attempt to clarify the therapeutic challenges in this disease. It also includes the first proposed treatment paradigm that integrates both EGFR mutational status and the sub-histologies, mucinous and nonmucinous BAC.