A LAK of Direction Misalignment Between the Goals of Learning Analytics and its Research Scholarship

Learning analytics defines itself with a focus on data from learners and learning environments, with corresponding goals of understanding and optimizing student learning. In this regard, learning analytics research, ideally, should be characterized by studies that make use of data from learners engaged in education systems, should measure student learning, and should make efforts to intervene and improve these learning environments

Mutational and Structural Analysis of KIR3DL1 Reveals a Lineage-Defining Allotypic Dimorphism That Impacts Both HLA and Peptide Sensitivity

Killer Ig-like receptors (KIRs) control the activation of human NK cells via interactions with peptide-laden HLAs. KIR3DL1 is a highly polymorphic inhibitory receptor that recognizes a diverse array of HLA molecules expressing the Bw4 epitope, a group with multiple polymorphisms incorporating variants within the Bw4 motif. Genetic studies suggest that KIR3DL1 variation has functional significance in several disease states, including HIV infection. However, owing to differences across KIR3DL1 allotypes, HLA-Bw4, and associated peptides, the mechanistic link with biological outcome remains unclear. In this study, we elucidated the impact of KIR3DL1 polymorphism on peptide-laden HLA recognition. Mutational analysis revealed that KIR residues involved in water-mediated contacts with the HLA-presented peptide influence peptide binding specificity. In particular, residue 282 (glutamate) in the D2 domain underpins the lack of tolerance of negatively charged C-terminal peptide residues. Allotypic KIR3DL1 variants, defined by neighboring residue 283, displayed differential sensitivities to HLA-bound peptide, including the variable HLA-B*57:01-restricted HIV-1 Gag-derived epitope TW10. Residue 283, which has undergone positive selection during the evolution of human KIRs, also played a central role in Bw4 subtype recognition by KIR3DL1. Collectively, our findings uncover a common molecular regulator that controls HLA and peptide discrimination without participating directly in peptide-laden HLA interactions. Furthermore, they provide insight into the mechanics of interaction and generate simple, easily assessed criteria for the definition of KIR3DL1 functional groupings that will be relevant in many clinical applications, including bone marrow transplantation

Teaching Healthcare Professional Students in Online Learning during COVID-19: Reflection of University Lecturers

Online education has been regarded as a lifeline for many education institutions during the COVID-19 pandemic, offering students a means to advance their education and career. While face-to-face teaching universities convert their education curricula to the online settings, many institutions lack effective online teaching strategies, leading to reduced student enrolment and satisfaction. Contrarily, we have been receiving an ever-increasing number of healthcare professional students in our learning department since the outbreak, while maintaining high satisfaction. These students work as registered professional key workers and study online. Among numerous measures taken to support this student group, this short paper reports four effective teaching practices we have implemented: (a) active use of adaptive learning, (b) Padlet discussions, (c) wellbeing webinars, and (d) resilience building. These teaching strategies are deemed to address weaknesses of online learning and offer emotional support to students. Our teaching practices will be useful to many universities supporting this crucial group of students in the online environment.N/

Peptide-Dependent Recognition of HLA-B*57:01 by KIR3DS1

Killer cell immunoglobulin-like receptors (KIRs) play an important role in the activation of natural killer (NK) cells, which in turn contribute to the effective immune control of many viral infections. In the context of HIV infection, the closely related KIR3DL1 and KIR3DS1 molecules, in particular, have been associated with disease outcome. Inhibitory signals via KIR3DL1 are disrupted by downregulation of HLA class I ligands on the infected cell surface and can also be impacted by changes in the presented peptide repertoire. In contrast, the activatory ligands for KIR3DS1 remain obscure. We used a structure-driven approach to define the characteristics of HLA class I-restricted peptides that interact with KIR3DL1 and KIR3DS1. In the case of HLA-B*57:01, we used this knowledge to identify bona fide HIV-derived peptide epitopes with similar properties. Two such peptides facilitated productive interactions between HLA-B*57:01 and KIR3DS1. These data reveal the presence of KIR3DS1 ligands within the HIV-specific peptide repertoire presented by a protective HLA class I allotype, thereby enhancing our mechanistic understanding of the processes that enable NK cells to impact disease outcome. IMPORTANCE Natural killer (NK) cells are implicated as determinants of immune control in many viral infections, but the precise molecular mechanisms that initiate and control these responses are unclear. The activating receptor KIR3DS1 in combination with HLA-Bw4 has been associated with better outcomes in HIV infection. However, evidence of a direct interaction between these molecules is lacking. In this study, we demonstrate that KIR3DS1 recognition of HLA-Bw4 is peptide dependent. We also identify HIV-derived peptide epitopes presented by the protective HLA-B*57:01 allotype that facilitate productive interactions with KIR3DS1. Collectively, these findings suggest a mechanism whereby changes in the peptide repertoire associated with viral infection provide a trigger for KIR3DS1 engagement and NK cell activation

Activating killer-cell immunoglobulin-like receptor haplotype influences clinical outcome following HLA-matched sibling haematopoietic stem cell transplantation

Natural killer cells are thought to influence the outcome of hematopoietic stem cell transplant (HSCT), impacting on relapse, overall survival, graft versus host disease and the control of infection, in part through the complex interplay between the large and genetically diverse killer immunoglobulin-like receptor (KIR) family and their ligands. This study examined the relationship between KIR gene content and clinical outcomes including the control of opportunistic infections such as cytomegalovirus in the setting of human leucocyte antigen (HLA)-matched sibling HSCT in an Australian cohort. The presence of the KIR B haplotype which contain more activating receptors in the donor, in particular centromeric B haplotype genes (Cen-B), was associated with improved overall survival of patients with acute myeloid leukemia (AML) undergoing sibling HSCT and receiving myeloablative conditioning. Donor Cen-B haplotype was also associated with reduced acute graft versus host disease grades II-IV whereas donor telomeric-B haplotype was associated with decreased incidence of CMV reactivation. In contrast, we were not able to demonstrate a reduced rate of relapse when the donor had KIR Cen-B, however relapse with a donor Cen-A haplotype was a competing risk factor to poor overall survival. Here we show that the presence of donor activating KIR led to improved outcome for the patient, potentially through reduced relapse rates and decreased incidence of acute GvHD translating to improved overall survival. This article is protected by copyright. All rights reserved

Performance of the GeneXpert Ebola Assay for Diagnosis of Ebola Virus Disease in Sierra Leone: A Field Evaluation Study

Background: Throughout the Ebola virus disease (EVD) epidemic in West Africa, field laboratory testing for EVD has relied on complex, multi-step real-time reverse transcription PCR (RT-PCR) assays; an accurate sample-to-answer RT-PCR test would reduce time to results and potentially increase access to testing. We evaluated the performance of the Cepheid GeneXpert Ebola assay on clinical venipuncture whole blood (WB) and buccal swab (BS) specimens submitted to a field biocontainment laboratory in Sierra Leone for routine EVD testing by RT-PCR (“Trombley assay”). Methods and Findings: This study was conducted in the Public Health England EVD diagnostic laboratory in Port Loko, Sierra Leone, using residual diagnostic specimens remaining after clinical testing. EDTA-WB specimens (n = 218) were collected from suspected or confirmed EVD patients between April 1 and July 20, 2015. BS specimens (n = 71) were collected as part of a national postmortem screening program between March 7 and July 20, 2015. EDTA-WB and BS specimens were tested with Xpert (targets: glycoprotein [GP] and nucleoprotein [NP] genes) and Trombley (target: NP gene) assays in parallel. All WB specimens were fresh; 84/218 were tested in duplicate on Xpert to compare WB sampling methods (pipette versus swab); 43/71 BS specimens had been previously frozen. In all, 7/218 (3.2%) WB and 7/71 (9.9%) BS samples had Xpert results that were reported as “invalid” or “error” and were excluded, leaving 211 WB and 64 BS samples with valid Trombley and Xpert results. For WB, 22/22 Trombley-positive samples were Xpert-positive (sensitivity 100%, 95% CI 84.6%–100%), and 181/189 Trombley-negative samples were Xpert-negative (specificity 95.8%, 95% confidence interval (CI) 91.8%–98.2%). Seven of the eight Trombley-negative, Xpert-positive (Xpert cycle threshold [Ct] range 37.7–43.4) WB samples were confirmed to be follow-up submissions from previously Trombley-positive EVD patients, suggesting a revised Xpert specificity of 99.5% (95% CI 97.0%–100%). For Xpert-positive WB samples (n = 22), Xpert NP Ct values were consistently lower than GP Ct values (mean difference −4.06, 95% limits of agreement −6.09, −2.03); Trombley (NP) Ct values closely matched Xpert NP Ct values (mean difference −0.04, 95% limits of agreement −2.93, 2.84). Xpert results (positive/negative) for WB sampled by pipette versus swab were concordant for 78/79 (98.7%) WB samples, with comparable Ct values for positive results. For BS specimens, 20/20 Trombley-positive samples were Xpert-positive (sensitivity 100%, 95% CI 83.2%–100%), and 44/44 Trombley-negative samples were Xpert-negative (specificity 100%, 95% CI 92.0%–100%). This study was limited to testing residual diagnostic samples, some of which had been frozen before use; it was not possible to test the performance of the Xpert Ebola assay at point of care. Conclusions: The Xpert Ebola assay had excellent performance compared to an established RT-PCR benchmark on WB and BS samples in a field laboratory setting. Future studies should evaluate feasibility and performance outside of a biocontainment laboratory setting to facilitate expanded access to testing

Mutational and Structural Analysis of KIR3DL1 Reveals a Lineage-Defining Allotypic Dimorphism That Impacts Both HLA and Peptide Sensitivity

Killer Ig-like receptors (KIRs) control the activation of human NK cells via interactions with peptide-laden HLAs. KIR3DL1 is a highly polymorphic inhibitory receptor that recognizes a diverse array of HLA molecules expressing the Bw4 epitope, a group with multiple polymorphisms incorporating variants within the Bw4 motif. Genetic studies suggest that KIR3DL1 variation has functional significance in several disease states, including HIV infection. However, owing to differences across KIR3DL1 allotypes, HLA-Bw4, and associated peptides, the mechanistic link with biological outcome remains unclear. In this study, we elucidated the impact of KIR3DL1 polymorphism on peptide-laden HLA recognition. Mutational analysis revealed that KIR residues involved in water-mediated contacts with the HLA-presented peptide influence peptide binding specificity. In particular, residue 282 (glutamate) in the D2 domain underpins the lack of tolerance of negatively charged C-terminal peptide residues. Allotypic KIR3DL1 variants, defined by neighboring residue 283, displayed differential sensitivities to HLA-bound peptide, including the variable HLA-B*57:01–restricted HIV-1 Gag-derived epitope TW10. Residue 283, which has undergone positive selection during the evolution of human KIRs, also played a central role in Bw4 subtype recognition by KIR3DL1. Collectively, our findings uncover a common molecular regulator that controls HLA and peptide discrimination without participating directly in peptide-laden HLA interactions. Furthermore, they provide insight into the mechanics of interaction and generate simple, easily assessed criteria for the definition of KIR3DL1 functional groupings that will be relevant in many clinical applications, including bone marrow transplantation

Long-Term Toxicity and Health-Related Quality of Life After Adjuvant Chemoradiation Therapy or Radiation Therapy Alone for High-Risk Endometrial Cancer in the Randomized PORTEC-3 Trial

PURPOSE: The survival results of the PORTEC-3 trial showed a significant improvement in both overall and failure-free survival with chemoradiation therapy versus pelvic radiation therapy alone. The present analysis was performed to compare long-term adverse events (AE) and health-related quality of life (HRQOL). METHODS AND MATERIALS: In the study, 660 women with high-risk endometrial cancer were randomly assigned to receive chemoradiation therapy (2 concurrent cycles of cisplatin followed by 4 cycles of carboplatin/paclitaxel) or radiation therapy alone. Toxicity was graded using Common Terminology Criteria for Adverse Events, version 3.0. HRQOL was measured using EORTC QLQ-C30 and CX24/OV28 subscales and compared with normative data. An as-treated analysis was performed. RESULTS: Median follow-up was 74.6 months; 574 (87%) patients were evaluable for HRQOL. At 5 years, grade ≥2 AE were scored for 78 (38%) patients who had received chemoradiation therapy versus 46 (24%) who had received radiation therapy alone (P = .008). Grade 3 AE did not differ significantly between the groups (8% vs 5%, P = .18) at 5 years, and only one new late grade 4 toxicity had been reported. At 3 and 5 years, sensory neuropathy toxicity grade ≥2 persisted after chemoradiation therapy in 6% (vs 0% after radiation therapy, P < .001) and more patients reported significant tingling or numbness at HRQOL (27% vs 8%, P < .001 at 3 years; 24% vs 9%, P = .002 at 5 years). Up to 3 years, more patients who had chemoradiation therapy reported limb weakness (21% vs 5%, P < .001) and lower physical (79 vs 87, P < .001) and role functioning (78 vs 88, P < .001) scores. Both treatment groups reported similar long-term global health/quality of life scores, which were better than those of the normative population. CONCLUSIONS: This study shows a long-lasting, clinically relevant, negative impact of chemoradiation therapy on toxicity and HRQOL, most importantly persistent peripheral sensory neuropathy. Physical and role functioning impairments were seen until 3 years. These long-term data are essential for patient information and shared decision-making regarding adjuvant chemotherapy for high-risk endometrial cancer

Killer cell immunoglobulin-like receptor 3DL1-mediated recognition of human leukocyte antigen B [Letter]

Members of the killer cell immunoglobulin-like receptor (KIR) family, a large group of polymorphic receptors expressed on natural killer (NK) cells, recognize particular peptide-laden human leukocyte antigen (pHLA) class I molecules and have a pivotal role in innate immune responses1. Allelic variation and extensive polymorphism within the three-domain KIR family (KIR3D, domains D0–D1–D2) affects pHLA binding specificity and is linked to the control of viral replication and the treatment outcome of certain haematological malignancies1, 2, 3. Here we describe the structure of a human KIR3DL1 receptor bound to HLA-B*5701 complexed with a self-peptide. KIR3DL1 clamped around the carboxy-terminal end of the HLA-B*5701 antigen-binding cleft, resulting in two discontinuous footprints on the pHLA. First, the D0 domain, a distinguishing feature of the KIR3D family, extended towards β2-microglobulin and abutted a region of the HLA molecule with limited polymorphism, thereby acting as an ‘innate HLA sensor’ domain. Second, whereas the D2–HLA-B*5701 interface exhibited a high degree of complementarity, the D1–pHLA-B*5701 contacts were suboptimal and accommodated a degree of sequence variation both within the peptide and the polymorphic region of the HLA molecule. Although the two-domain KIR (KIR2D) and KIR3DL1 docked similarly onto HLA-C4, 5 and HLA-B respectively, the corresponding D1-mediated interactions differed markedly, thereby providing insight into the specificity of KIR3DL1 for discrete HLA-A and HLA-B allotypes. Collectively, in association with extensive mutagenesis studies at the KIR3DL1–pHLA-B*5701 interface, we provide a framework for understanding the intricate interplay between peptide variability, KIR3D and HLA polymorphism in determining the specificity requirements of this essential innate interaction that is conserved across primate species

Killer cell immunoglobulin-like receptor 3DL1 polymorphism defines distinct hierarchies of HLA class I recognition

Natural killer (NK) cells play a key role in immunity, but how HLA class I (HLA-I) and killer cell immunoglobulin-like receptor 3DL1 (KIR3DL1) polymorphism impacts disease outcome remains unclear. KIR3DL1 (*001/*005/*015) tetramers were screened for reactivity against a panel of HLA-I molecules. This revealed different and distinct hierarchies of specificity for each KIR3DL1 allotype, with KIR3DL1*005 recognizing the widest array of HLA-I ligands. These differences were further reflected in functional studies using NK clones expressing these specific KIR3DL1 allotypes. Unexpectedly, the Ile/Thr80 dimorphism in the Bw4-motif did not categorically define strong/weak KIR3DL1 recognition. Although the KIR3DL1*001, *005, and *015 polymorphisms are remote from the KIR3DL1-HLA-I interface, the structures of these three KIR3DL1-HLA-I complexes showed that the broader HLA-I specificity of KIR3DL1*005 correlated with an altered KIR3DL1*005 interdomain positioning and increased mobility within its ligand-binding site. Collectively, we provide a generic framework for understanding the impact of KIR3DL1 polymorphism on the recognition of HLA-I allomorphs