Explore the vast range of titles available.

Bacteriophage T7 and T7-like bacteriophages are valuable genetic models for lytic phage biology that have heretofore been intractable with in vivo genetic engineering methods. This manuscript describes that the presence of λ Red recombination proteins makes in vivo recombineering of T7 possible, so that single base changes and whole gene replacements on the T7 genome can be made. Red recombination functions also increase the efficiency of T7 genome DNA transfection of cells by ~100-fold. Likewise, Red function enables two other T7-like bacteriophages that do not normally propagate in E. coli to be recovered following genome transfection. These results constitute major technical advances in the speed and efficiency of bacteriophage T7 engineering and will aid in the rapid development of new phage variants for a variety of applications.

Approximately 40% of patients with cancer are eligible for check-point inhibitor (CPI) therapy. Little research has examined the potential cognitive impact of CPIs. First-line CPI therapy offers a unique research opportunity without chemotherapy-related confounders. The purpose of this prospective, observational pilot was to (1) demonstrate the feasibility of prospective recruitment, retention, and neurocognitive assessment for older adults receiving first-line CPI(s) and (2) provide preliminary evidence of changes in cognitive function associated with CPI(s). Patients receiving first-line CPI(s) (CPI Group) were assessed at baseline (n = 20) and 6 months (n = 13) for self-report of cognitive function and neurocognitive test performance. Results were compared to age-matched controls without cognitive impairment assessed annually by the Alzheimer’s Disease Research Center (ADRC). Plasma biomarkers were measured at baseline and 6 months for the CPI Group. Estimated differences for CPI Group scores prior to initiating CPIs (baseline) trended to lower performance on the Montreal Cognitive Assessment-Blind (MOCA-Blind) test compared to the ADRC controls (p = 0.066). Controlling for age, the CPI Group’s 6-months MOCA-Blind performance was lower than the ADRC control group’s 12-months performance (p = 0.011). No significant differences in biomarkers were detected between baseline and 6 months, although significant correlations were noted for biomarker change and cognitive performance at 6 months. IFNγ, IL-1β, IL-2, FGF2, and VEGF were inversely associated with Craft Story Recall performance (p < 0.05), e.g., higher levels correlated with poorer memory performance. Higher IGF-1 and VEGF correlated with better letter-number sequencing and digit-span backwards performance, respectively. Unexpected inverse correlation was noted between IL-1α and Oral Trail-Making Test B completion time. CPI(s) may have a negative impact on some neurocognitive domains and warrant further investigation. A multi-site study design may be crucial to fully powering prospective investigation of the cognitive impact of CPIs. Establishment of a multi-site observational registry from collaborating cancer centers and ADRCs is recommended.

BackgroundNexImmune’s Artificial Immune Modulation (AIM) nanoparticle (NP) platform (AIM INJ) is an injectable multi-antigen specific off-the-shelf immunotherapy designed to directly modulate T cell responses in vivo. It consists of a PLA-PEG NP conjugated with two proteins, a dimeric IgG MHC-class I fusion protein loaded with a tumor peptide and an anti-CD28 antibody for co-stimulation. Multiple batches of NPs, loaded with a single peptide, are mixed to create a multi-antigen specific NP product. AIM INJ NP expanded T cells are antigen-specific, polyfunctional and consist of memory phenotypes associated with anti-tumor activity and immunologic memory.MethodsWe performed adoptive transfer of OVA-TCR transgenic OT-1 cells into C57BL/6 mice followed by S.C. injection of OVA peptide-loaded NPs. NPs between 35 and 90 nm in size and two doses were tested. To further evaluate the efficacy in a solid tumor model, C57BL/6 mice were implanted with B16F10-OVA tumor cells. On day 6, 1.5 million OT-1 T cells were adoptively transferred into the tumor-bearing mice. Control NPs or OVA-NPs were injected S.C. on days 7, 14 and 21 after tumor injection and tumor volume was monitored.ResultsWe demonstrated the ability of AIM INJ NPs to activate and expand antigen-specific T cells in vivo. NPs of all sizes induced expansion of OT-1 T cells while non-specific control NPs did not. In B16F10-OVA tumor model, treatment of mice with OVA-NPs significantly delayed tumor growth and increased survival as compared to mice treated with control NPs. OVA-NPs treated mice had significantly higher amounts of OVA specific tumor infiltrating lymphocytes and higher percentage of functional OT-1 T cells in spleen as demonstrated in ex vivo killing assays. Additional data from an ongoing B16F10 mouse melanoma model with AIM INJ NPs targeting the endogenous melanoma antigen gp100 will be presented.ConclusionsAIM INJ NPs can activate, expand antigen-specific CD8+ T cells and elicit anti-tumor activity in vivo. The combination of antigen-peptide targets loaded on the AIM INJ NP can be changed to address different tumors. These studies along with other in vivo pre-clinical studies including further evaluation of a dose regimen and route of administration will be used to support our INDs for using AIM INJ in Phase 1 studies for solid tumors. AIM INJ potentially addresses gaps in immunotherapies by driving multiple tumor antigen-specific T cells into the tumor, establishing T cell memory for durability and using an off-the-shelf modality supporting easier access and scalability.

Goal-directed point-of-care ultrasound (PoCUS) protocols have been shown to improve the diagnostic accuracy of the initial clinical assessment of the critically ill patient. The diagnostic impact of the Abdominal and Cardiac Evaluation with Sonography in Shock (ACES) protocol was assessed in simulated emergency medical scenarios. Following a focused PoCUS training program, the diagnostic accuracy, confidence, and precision of 12 medical learners participating in standardized scenarios were tested using high-fidelity clinical and ultrasound simulators. Participants were assessed during 72 simulated cardiorespiratory scenarios. Differential diagnoses were collected from participants before and after PoCUS in each scenario, and confidence surveys were completed. Data were analysed using R software. Prior to PoCUS, 45 (62.5%) correct primary diagnoses were made compared with 64 (88.9%) following PoCUS (χ2=14, 1df, p=0.0002). PoCUS was also shown to increase participants' confidence in their diagnoses. The mean confidence in diagnosis score pre-PoCUS was 52.2 (SD=14.7), whereas post-PoCUS it was 81.7 (SD=9.5). The estimated difference in means (-28.36) was significant (t=-7.71, p<0.0001). Using PoCUS, participants were further able to narrow their differential diagnoses. The median number of diagnoses for each patient pre-PoCUS was 3.5 (interquartile range [IQR]=3.8, 3.0) with a median of 2.3 (IQR=2.9,1.5) diagnoses post-PoCUS. The difference was significant (W=0, p<0.001). This pilot study suggests that, in medical learners newly competent in PoCUS, the addition of an ACES PoCUS protocol to standard clinical assessment improves diagnostic accuracy, confidence, and precision in simulated cardiorespiratory scenarios. This is consistent with clinical studies and supports the use of ultrasound during medical simulation.

BackgroundBispecific TCEs are a new class of immunotherapeutic molecules for the treatment of cancer. Bispecific TCE molecules enhance the patient’s immune response to tumors by retargeting T cells to tumor cells. However, Bispecific TCEs show rapid clearance with a serum half-life of a few hours, therefore the administration of bispecific TCE often requires high doses and continuous intravenous infusion, which can result in T cell exhaustion at higher doses.MethodsHere we evaluated if combining bispecific TCE treatment with NexImmunes AIM ACT T cells (AIM ACT) can further improve the effect of the bispecific TCE. For this study we have generated 5 AML specific bispecific TCEs targeting FLT3 (two different molecules), CD123, CD33 and Siglec-6 and tested them in vitro for AML-specific tumor cell killing in combination with either AML-specific AIM ACT or non-specific bulk CD4 and CD8 T cells.ResultsWe present data that the combination of bispecific TCE and AIM ACT is superior to bispecific TCE monotreatment that relies on engaging with the host endogenous tumor non-specific T cell repertoire. All bispecific TCE mediated killing of AML cell lines, when combined with CD8 T cells, although the Siglec-6 specific TCE had the lowest effect due to low surface expression of Siglec6 in these tested cell lines. Specifically, we interrogated the potency of different types of T cells as bispecific effectors including CD4 and CD8 control T cells from healthy volunteers in comparison to our AIM ACT. Analysis of TCR-mediated killing (without bispecific TCE) showed that, both non-specific bulk CD4 and CD8 T cells had little potency while AML-specific AIM ACT can mediate effector to target cell ratio dependent target cell killing. Overall target cell killing was most efficient when using AIM ACT as effector cells. Notably, bispecific TCE concentrations in the picomolar range achieved greater than 80% target cell killing with AIM ACT.ConclusionsTogether these in vitro studies demonstrate the synergistic effect of bispecific TCEs and our multi-antigen-specific AIM ACT with the potential to enhance the therapeutic effect while at the same time lowering the requirement for high dose and continuous infusion of the bispecific TCE. In addition, to validate our findings in vivo we will present data from our ongoing in vivo study evaluating the combination of a CD123 specific bispecific TCE in combination with either our multi-AML antigen-peptide specific AIM ACT or freshly isolated bulk CD8+ T cells in a THP-1/NSG humanized mouse model.

In addition to complications of acute diseases, chronic viral infections are linked to both malignancies and autoimmune disorders. Lack of adequate treatment options for Epstein-Barr virus (EBV), Human T-lymphotropic virus type 1 (HTLV-1), and human papillomavirus (HPV) remains. The NexImmune Artificial Immune Modulation (AIM) nanoparticle platform can be used to direct T cell responses by mimicking the dendritic cell function. In one application, AIM nanoparticles are used ex vivo to enrich and expand (E+E) rare populations of multi-antigen-specific CD8 + T cells for use of these cells as an AIM adoptive cell therapy. This study has demonstrated using E+E CD8 + T cells, the functional relevance of targeting EBV, HTLV-1, and HPV. Expanded T cells consist primarily of effector memory, central memory, and self-renewing stem-like memory T cells directed at selected viral antigen peptides presented by the AIM nanoparticle. T cells expanded against either EBV- or HPV-antigens were highly polyfunctional and displayed substantial in vitro cytotoxic activity against cell lines expressing the respective antigens. Our initial work was in the context of exploring T cells expanded from healthy donors and restricted to human leukocyte antigen (HLA)-A*02:01 serotype. AIM Adoptive Cell Therapies (ACT) are also being developed for other HLA class I serotypes. AIM adoptive cell therapies of autologous or allogeneic T cells specific to antigens associated with acute myeloid leukemia and multiple myeloma are currently in the clinic. The utility and flexibility of the AIM nanoparticle platform will be expanded as we advance the second application, an AIM injectable off-the-shelf nanoparticle, which targets multiple antigen-specific T cell populations to either activate, tolerize, or destroy these targeted CD8 + T cells directly in vivo, leaving non-target cells alone. The AIM injectable platform offers the potential to develop new multi-antigen specific therapies for treating infectious diseases, cancer, and autoimmune diseases.

We present the geography of Oxia Planum, the landing site for the ExoMars 2022 mission. This map provides the planetary science community with a framework to understand this, until recently, unexplored area. The map comprises (1) a mosaic of the panchromatic Context Camera (CTX) Digital Elevation Models (DEM) and Ortho Rectified Images (ORI) controlled to the High Resolution Stereo Camera (HRSC) multiorbit Digital Elevation Models (DEM) and (2) a mosaic of Colour and Stereo Surface Imaging System (CaSSIS) synthetic colour data products, registered to the CTX ORI mosaic. We define a grid of exploration quadrangles (quads) and an informal group of geographic regions to describe Oxia Planum. These regions bridge the scale gap between features observed on large areas (∼100s km 2 ) and the local geography (10s km 2 ) relevant to the Rosalind Franklin rover's operations in Oxia Planum.

Despite awake tracheal intubation being considered the safest method of intubation for patients with predicted difficult airways, there is limited evidence and poor availability of training interventions to assist emergency medicine physicians achieve competency in this technique. Here, we describe a novel, cadaver-based course for emergency medicine physicians to acquire skills in awake tracheal intubation. A convenience sample of 15 emergency medicine physicians from across Canada participated in the pilot course. Questionnaire data regarding the course’s usefulness and participants’ confidence in awake tracheal intubation were collected. All 15 participants completed the course, and questionnaire data showed that participants found the course useful and practice-changing. Three physicians reported successfully performing awake tracheal intubation in the emergency department during the 3–6-month follow-up period. Expansion of similar courses could help emergency medicine physicians acquire the skills necessary to safely perform awake tracheal intubation. Future studies should focus on optimizing training protocols, with a focus on practical methods to improve long-term skill retention.

The bacterial transposon Tn7 recognizes replicating DNA as a target with a preference for the region where DNA replication terminates in the Escherichia coli chromosome. It was previously shown that DNA double-strand breaks in the chromosome stimulate Tn7 transposition where transposition events occur broadly around the point of the DNA break. We show that individual DNA breaks actually activate a series of small regional hotspots in the chromosome for Tn7 insertion. These hotspots are fixed and become active only when a DNA break occurs in the same region of the chromosome. We find that the distribution of insertions around the break is not explained by the exonuclease activity of RecBCD moving the position of the DNA break, and stimulation of Tn7 transposition is not dependent on RecBCD. We show that other forms of DNA damage, like exposure to UV light, mitomycin C, or phleomycin, also stimulate Tn7 transposition. However, inducing the SOS response does not stimulate transposition. Tn7 transposition is not dependent on any known specific pathway of replication fork reactivation as a means of recognizing DNA break repair. Our results are consistent with the idea that Tn7 recognizes DNA replication involved in DNA repair and reveals discrete regions of the chromosome that are differentially activated as transposition targets.