Lee, James S.

Abstract Eosinophils comprise only 1-3% of circulating leukocytes but are often a diagnostic feature associated with a variety of inflammatory and disease states, including parasitic and fungal infections, allergic diseases (e.g., asthma, rhinitis and sensitivities to specific foods), cancer, and transplant rejection. The accurate evaluations of eosinophilia as well as the release of stored eosinophil granule proteins are important for the monitoring disease progression and/or assessing the effectiveness of a given treatment strategy(ies). Despite the availability of detection methods for each of the eosinophil granule proteins logistical difficulties limiting either the assays specificity and/or sensitivity have prevented their extensive use. We have generated unique eosinophil peroxidase specific monoclonal antibodies (EPX-mAb) and a high throughput sandwich ELISA assay as a means of overcoming these difficulties. Our EPX-mAb based ELISA is ~10 times more sensitive than traditional OPD based activity assays and allows detection of EPX in mouse BAL fluid after an acute OVA protocol as well as EPX release from mouse eosinophils stimulated ex vivo. The assay is highly specific and gives no signal in samples from EPX deficient mice even with massive eosinophilia (e.g., EPX deficient IL-5 transgenic mice). More significantly, this assay detects EPX in human tissue extracts and biological fluids and thus represents novel diagnostic assay previously unavailable in clinical settings.

Abstract Eosinophil effector functions have been hypothesized to be mediated in part by the release of proteins stored in the secondary granules of mature cells of this leukocyte lineage. Major basic protein-1 (MBP-1) and eosinophil peroxidase (EPO) comprise the majority of protein in these granules. No role has been speculated for these proteins in eosinophilopoiesis and/or the accumulation of mature cells in circulation. Methods: Eosinophilopoiesis and eosinophil accumulation in the periphery were assessed in single and double knockout (MBP-1-/- and/or EPO-/-) mice. Bone marrow and peripheral blood leukocytes were assessed by IHC, FACS and in vitro cell culture assays. Mice were subjected to an acute OVA protocol assessing induced pulmonary pathologies in each of the strains of granule protein knockout mice. Results: We demonstrate that, unlike the single deficiency of MBP-1 or EPO, the absence of both granule proteins resulted in the loss of peripheral blood eosinophils. IHC assessments of bone marrow and spleen demonstrate that eosinophil lineage commitment occurs in these mice. However, these assessments and FACS studies demonstrated a blockade in the maturation of eosinophil-lineage committed cells. This blockade is not rescued by ex vivo culture or by bone marrow engraftment into wild type recipient mice. Similar to other eosinophil-less mouse models, MBP-1-/-/EPO-/- mice also fail to develop pulmonary inflammation in an OVA protocol.

Focus on residents' role in teaching and learning has become a topic of increasing interest underscored by the responsibility that physicians in training are given as facilitators of medical student rotations, supervisors of peers and patient educators. Studies demonstrate that more developed teaching skills are predictive of increased knowledge base and improved clinical skill. As a coveted competency, development of teaching skill has become an established milestone in residency programs and a requirement by regulatory agencies (ACGME, LCME) that training institutions provide more opportunities for formal Resident‐as‐Teacher programs (RAT). In keeping with the authentic learning curriculum, the Student‐as‐Teacher (SAT) program in the Department of Anatomy, Mayo Clinic offers a structured and formal near‐peer teaching opportunity to third year medical students for advancing teaching skills. The program selects an average of 5–6 applicants to participate in teaching a 7‐week Anatomy block for first year medical students in an apprenticeship‐based model that emphasizes (1) Teamwork, (2) Leadership, (3) Lifelong learning, (4) Communication, (5) Core Knowledge, and (6) Teaching Skills/Professional development through individualized mentoring, structured debriefing, and reflective diaries. The purpose of this study is to assess the effectiveness of the apprenticeship model by measuring changes in the targeted competencies in the context of teaching practice. Teaching assistants (TAs) were asked to reflect and evaluate their pre‐ and post‐teaching experience in SAT program on a visual analog scale (VAS). All 5 TAs voluntarily responded to the survey. De‐identified VAS ratings were converted into numerical data from 1 to 100. Most reported increase in perception was in the area of non‐technical skills development: providing feedback (59.7; P = 0.0009); understanding expectations and teaching skills required in medical education (39.7; P = 0.002); and understanding teamwork in teaching role (33.1; P = 0.025). Additionally, TAs appreciated increased acquisition of technical skills: knowledge in anatomy, embryology and radiology (31.4; P = 007). Thematic analysis of responses generated a list of themes which included “appreciation for learning of non‐technical skills” and “skills in providing feedback”. The role of basic science educators is extended through facilitation of future physician required competencies in early medical education. While improvement of anatomical knowledge is an obvious benefit to medical students, improvement of non‐technical skills is reinforced by opportunity of the near‐peer teaching experience. In a teaching role, non‐technical skills supported through the art of “learning by doing” provides senior medical students with an authentic experience and ability to turn the intangible into the tangible. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .

ABSTRACT Human respiratory syncytial virus (RSV) is a major cause of morbidity and severe lower respiratory tract disease in the elderly and very young, with some infants developing bronchiolitis, recurrent wheezing, and asthma following infection. Previous studies in humans and animal models have shown that vaccination with formalin-inactivated RSV (FI-RSV) leads to prominent airway eosinophilic inflammation following RSV challenge; however, the roles of pulmonary eosinophilia in the antiviral response and in disease pathogenesis are inadequately understood. In vivo studies in mice with eotaxin and/or interleukin 5 (IL-5) deficiency showed that FI-RSV vaccination did not lead to enhanced pulmonary disease, where following challenge there were reduced pulmonary eosinophilia, inflammation, Th2-type cytokine responses, and altered chemokine (TARC and CCL17) responses. In contrast to wild-type mice, RSV was recovered at high titers from the lungs of eotaxin- and/or IL-5-deficient mice. Adoptive transfer of eosinophils to FI-RSV-immunized eotaxin- and IL-5-deficient (double-deficient) mice challenged with RSV was associated with potent viral clearance that was mediated at least partly through nitric oxide. These studies show that pulmonary eosinophilia has dual outcomes: one linked to RSV-induced airway inflammation and pulmonary pathology and one with innate features that contribute to a reduction in the viral load. IMPORTANCE This study is critical to understanding the mechanisms attributable to RSV vaccine-enhanced disease. This study addresses the hypothesis that IL-5 and eotaxin are critical in pulmonary eosinophil response related to FI-RSV vaccine-enhanced disease. The findings suggest that in addition to mediating tissue pathology, eosinophils within a Th2 environment also have antiviral activity.