Potent HPIV3-neutralizing IGHV5-51 Antibodies Identified from Multiple Individuals Show L Chain and CDRH3 Promiscuity.

Human parainfluenza virus 3 (HPIV3) is a widespread pathogen causing severe and lethal respiratory illness in at-risk populations. Effective countermeasures are in various stages of development; however, licensed therapeutic and prophylactic options are not available. The fusion glycoprotein (HPIV3 F), responsible for facilitating viral entry into host cells, is a major target of neutralizing Abs that inhibit infection. Although several neutralizing Abs against a small number of HPIV3 F epitopes have been identified to date, relatively little is known about the Ab response to HPIV3 compared with other pathogens, such as influenza virus and SARS-CoV-2. In this study, we aimed to characterize a set of HPIV3-specific Abs identified in multiple individuals for genetic signatures, epitope specificity, neutralization potential, and publicness. We identified 12 potently neutralizing Abs targeting three nonoverlapping epitopes on HPIV3 F. Among these, six Abs identified from two different individuals used Ig heavy variable gene IGHV 5-51, with five of the six Abs targeting the same epitope. However, despite the use of the same H chain variable (VH) gene, these Abs used multiple different L chain variable genes (VL) and diverse H chain CDR 3 (CDRH3) sequences. Together, these results provide further information about the genetic and functional characteristics of HPIV3-neutralizing Abs and suggest the existence of a reproducible VH-dependent Ab response associated with VL and CDRH3 promiscuity. Understanding sites of HPIV3 F vulnerability and the genetic and molecular characteristics of Abs targeting these sites will help guide efforts for effective vaccine and therapeutic development.

Structural basis for respiratory syncytial virus and human metapneumovirus neutralization.

Respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) continue to be a global burden to infants, the elderly, and immunocompromised individuals. In the past ten years, there has been substantial progress in the development of new vaccine candidates and therapies against these viruses. These advancements were guided by the structural elucidation of the major surface glycoproteins for these viruses, the fusion (F) protein and attachment (G) protein. The identification of immunodominant epitopes on the RSV F and hMPV F proteins has expanded current knowledge on antibody-mediated immune responses, which has led to new approaches for vaccine and therapeutic development through the stabilization of pre-fusion constructs of the F protein and pre-fusion-specific monoclonal antibodies with high potency and efficacy. In this review, we describe structural characteristics of known antigenic sites on the RSV and hMPV proteins, their influence on the immune response, and current progress in vaccine and therapeutic development.

A Pan-Pneumovirus vaccine based on immunodominant epitopes of the fusion protein.

Respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) are two leading causes of severe respiratory infections in children, the elderly, and immunocompromised patients. The fusion (F) protein is the major target of neutralizing antibodies. Recent developments in stabilizing the pre-fusion conformation of the F proteins, and identifying immunodominant epitopes that elicit potent neutralizing antibodies have led to the testing of numerous pre-fusion RSV F-based vaccines in clinical trials. We designed and tested the immunogenicity and protective efficacy of a chimeric fusion protein that contains immunodominant epitopes of RSV F and hMPV F (RHMS-1). RHMS-1 has several advantages over vaccination with pre-fusion RSV F or hMPV F, including a focus on recalling B cells to the most important protective epitopes and the ability to induce protection against two viruses with a single antigen. RHMS-1 was generated as a trimeric recombinant protein, and analysis by negative-stain electron microscopy demonstrated the protein resembles the pre-fusion conformation. Probing of RHMS-1 antigenicity using a panel of RSV and hMPV F-specific monoclonal antibodies (mAbs) revealed the protein retains features of both viruses, including the pre-fusion site Ø epitope of RSV F. Mice immunized with RHMS-1 generated neutralizing antibodies to both viruses and were completely protected from RSV or hMPV challenge. Overall, this study demonstrates protection against two viruses with a single antigen and supports testing of RHMS-1 in additional pre-clinical animal models.

Institutional Interventional Radiology Symposium Increases Medical Student Interest and Identifies Target Recruitment Candidates.

OBJECTIVES: To assess and raise medical student interest in interventional radiology (IR); and to evaluate student response across gender, level of training, and surgical vs nonsurgical specialty interest. MATERIALS AND METHODS: All Ohio medical students were invited to an IR Symposium held by a large academic medical center in central Ohio. The program encompassed didactic lectures, hands-on simulation models, and a networking luncheon with faculty, trainees, and industry partners. All attendees completed an anonymous, 5-point Likert scaled survey preattending and postattending the event to assess their awareness of IR as a specialty, understanding of the current training pathways, and level of interest. RESULTS: A total of 46 participants (M:F 60%:40%, MS1-53%, MS2-36%, and MS3-11%) attended the symposium. The cohort demonstrated increased interest in pursuing a career in IR following the symposium (4.12 vs 3.70, P < 0.001). Students with an interest in a nonsurgical specialty showed an increased interest in IR (4.20 vs 3.68, P < 0.001), whereas surgically oriented students did not demonstrate a significant increase (4.00 vs 3.71, P = 0.375). No statistically significant differences were noted across gender or level of training. The symposium experience significantly increased understanding of the IR training pathways (4.51 vs 2.94, P < 0.001). Students rated lectures (57%) and endovascular simulators (41%) as the most useful experiences. CONCLUSIONS: This study demonstrated the role of symposia in improving medical student awareness of IR and training pathways. Findings were validated across gender and training level, and identified the subset of students with nonsurgical interests as most responsive to such intervention and potential recruitment.

Implementation of an Innovative Tablet-based Curriculum for Radiology Resident Education.

RATIONALE AND OBJECTIVES: The aim of this study was to prospectively examine the impact of a tablet-based curriculum on the radiology resident educational experience. MATERIALS AND METHODS: A comprehensive tablet-based curriculum was developed by creating subspecialty modules with appropriate content level for each required rotation at our diagnostic radiology residency program. Daily assignments included key learning points, readings, and reference presentation slides, covering all objectives published by the ABR Core Exam Study Guide. Residents were provided with iPad devices preconfigured with the curriculum and online access to most major radiology textbooks available in our institutional digital library. Assessment surveys were administered at baseline and 12 months following curriculum implementation. RESULTS: Twenty-two residents completed both surveys. In comparing the pre versus postsurvey results, 32% versus 73% residents agreed or strongly agreed that study resources were well-organized, 41% versus 91% agreed or strongly agreed that study resources were easily accessible, 27% versus 77% agreed or strongly agreed that the modules encouraged active learning, 18% versus 82% agreed or strongly agreed that resources motivate them to study daily, 36% versus 82% agreed or strongly agreed that the resources adequately prepared the resident for the radiology board exam, and 36% versus 82% agreed or strongly agreed that they were satisfied with the resources provided by the residency program (p < 0.05). CONCLUSION: Our study demonstrated the positive impact of implementing a complete tablet-based curriculum on radiology resident motivation, satisfaction, and engagement. Use of mobile tablet devices has the potential to dramatically transform content delivery in residency education.

Vaccination with irradiated tumor cells pulsed with an adjuvant that stimulates NKT cells is an effective treatment for glioma.

PURPOSE: The prognosis for patients with glioblastoma multiforme (GBM) remains extremely poor despite recent treatment advances. There is an urgent need to develop novel therapies for this disease. EXPERIMENTAL DESIGN: We used the implantable GL261 murine glioma model to investigate the therapeutic potential of a vaccine consisting of intravenous injection of irradiated whole tumor cells pulsed with the immuno-adjuvant α-galactosylceramide (α-GalCer). RESULTS: Vaccine treatment alone was highly effective in a prophylactic setting. In a more stringent therapeutic setting, administration of one dose of vaccine combined with depletion of regulatory T cells (Treg) resulted in 43% long-term survival and the disappearance of mass lesions detected by MRI. Mechanistically, the α-GalCer component was shown to act by stimulating "invariant" natural killer-like T cells (iNKT cells) in a CD1d-restricted manner, which in turn supported the development of a CD4(+) T-cell-mediated adaptive immune response. Pulsing α-GalCer onto tumor cells avoided the profound iNKT cell anergy induced by free α-GalCer. To investigate the potential for clinical application of this vaccine, the number and function of iNKT cells was assessed in patients with GBM and shown to be similar to age-matched healthy volunteers. Furthermore, irradiated GBM tumor cells pulsed with α-GalCer were able to stimulate iNKT cells and augment a T-cell response in vitro. CONCLUSIONS: Injection of irradiated tumor cells loaded with α-GalCer is a simple procedure that could provide effective immunotherapy for patients with high-grade glioma.

Pathologies of the appendix: a 10-year review of 4670 appendicectomy specimens.

BACKGROUND: Debate surrounds the management of the macroscopically normal appendix. Current literature recommends its removal given the high incidence of microscopic appendicitis, and other unusual pathologies in the normal-looking appendix. Negative appendicectomies are reported on the decline with increased use of diagnostic radiological adjuncts. METHODS: This study analysed pathologies of the appendix over 10 years in the Pathology Department in Canberra. A positive appendicectomy was defined as acute appendicitis, faecoliths, worms, endometriosis or appendiceal tumours. We reviewed the positive appendicectomy rate over this time period. RESULTS: There were 4670 appendicectomy specimens in 2386 males (51.1%) and 2284 (49%) females. The incidence of acute appendicitis was 71.3% and the positive appendicectomy rate was 76.3%. There were significantly fewer negative appendicectomies in males (16.8%) compared with females (31.0%). There was no appreciable change in this trend over the study period. Of the positive appendicectomies, there were 129 (3.6%) faecoliths. Of these, only 39.5% had concomitant appendicitis. There were 44 (1.2%) specimens identified with worms. Of these, 40.9% had concomitant appendicitis. There were 14 cases of endometriosis of the appendix of which 36% had concomitant appendicitis. There were 58/3562 (1.6%) appendiceal tumours within the positive appendicectomy group the majority of which were carcinoid tumours (65.5%). CONCLUSION: There is a higher incidence of negative appendicectomies in women compared with men, which is similar to other published studies. Faecoliths and worms are a known cause of appendiceal colic and in our series were identified mostly in the absence of histological evidence of appendicitis.

Gleason grading: past, present and future.

In 1966 Donald Gleason developed his grading and scoring system for prostatic adenocarcinoma. This classification was refined in 1974 and gained almost universal acceptance, being classified as a category 1 prognostic parameter by the College of American Pathologists. Modifications to the classification were recommended at a conference convened by the International Society of Urological Pathology (ISUP) in 2005. This modified classification has resulted in a significant upgrading of tumours, although some studies have shown a greater concordance between needle biopsy and radical prostatectomy scores when compared to classical Gleason (CG) grading. The ISUP consensus conference recommended that for needle biopsies higher tertiary patterns should be incorporated into the final Gleason score, and this has been correlated with biochemical failure, tumour volume and mortality. Recently the validity of including cribriform glands as a component of Gleason pattern 3 has been questioned and it has been recommended that all tumours showing cribriform architecture should be classified as Gleason pattern 4. The recommendations arising from the 2005 Consensus Conference were largely unsupported by validating data, yet this new grading system has achieved widespread usage. It is unfortunate that recent suggestions for further modification are similarly lacking in supporting evidence. In view of this it is recommended that the Modified Gleason Scoring Classification should continue to be utilized in its original (2005) format and that any future alterations should be implemented only when mandated by tumour-related outcome studies.

Side population is not necessary or sufficient for a cancer stem cell phenotype in glioblastoma multiforme.

There is strong evidence for the existence of cancer stem cells (CSCs) in the aggressive brain tumor glioblastoma multiforme (GBM). These cells have stem-like self-renewal activity and increased tumor initiation capacity and are believed to be responsible for recurrence due to their resistance to therapy. Several techniques have been used to enrich for CSC, including growth in serum-free defined media to induce sphere formation, and isolation of a stem-like cell using exclusion of the fluorescent dye Hoechst 33342, the side population (SP). We show that sphere formation in GBM cell lines and primary GBM cells enriches for a CSC-like phenotype of increased self-renewal gene expression in vitro and increased tumor initiation in vivo. However, the SP was absent from all sphere cultures. Direct isolation of the SP from the GBM lines did not enrich for stem-like activity in vitro, and tumor-initiating activity was lower in sorted SP compared with non-SP and parental cells. Transient exposure to doxorubicin enhanced both CSC and SP frequency. However, doxorubicin treatment altered the cytometric profile and obscured the SP demonstrating the difficulty of identifying SP in cells under stress. Doxorubicin-exposed cells showed a transient increase in SP, but the doxorubicin-SP cells were still not enriched for a stem-like self-renewal phenotype. These data demonstrate that the GBM SP does not necessarily contribute to self-renewal or tumor initiation, key properties of a CSC, and we advise against using SP to enumerate or isolate CSC.