Metabolic priming of GD2 TRAC -CAR T cells during manufacturing promotes memory phenotypes while enhancing persistence

Manufacturing Chimeric Antigen Receptor (CAR) T cell therapies is complex, with limited understanding of how media composition impact T-cell phenotypes. CRISPR/Cas9 ribonucleoproteins can precisely insert a CAR sequence while disrupting the endogenous T cell receptor alpha constant ( TRAC ) gene resulting in TRAC -CAR T cells with an enriched stem cell memory T-cell population, a process that could be further optimized through modifications to the media composition. In this study we generated anti-GD2 TRAC -CAR T cells using "metabolic priming" (MP), where the cells were activated in glucose/glutamine low media and then expanded in glucose/glutamine high media. T cell products were evaluated using spectral flow cytometry, metabolic assays, cytokine production, cytotoxicity assays in vitro and potency against human GD2+ xenograft neuroblastoma models in vivo . Compared to standard TRAC -CAR T cells, MP TRAC -CAR T cells showed less glycolysis, higher CCR7/CD62L expression, more bound NAD(P)H activity and reduced IFN-γ, IL-2, IP-10, IL-1β, IL-17, and TGFβ production at the end of manufacturing ex vivo , with increased central memory CAR T cells and better persistence observed in vivo . Metabolic priming with media during CAR T cell biomanufacturing can minimize glycolysis and enrich memory phenotypes ex vivo , which could lead to better responses against solid tumors in vivo .

Virus-free CRISPR knock-in of a chimeric antigen receptor into KLRC1 generates potent GD2-specific natural killer cells

Natural killer (NK) cells are an appealing off-the-shelf, allogeneic cellular therapy due to their cytotoxic profile. However, their activity against solid tumors remains suboptimal in part due to the upregulation of NK-inhibitory ligands, such as HLA-E, within the tumor microenvironment. Here, we utilize CRISPR-Cas9 to disrupt the KLRC1 gene (encoding the HLA-E-binding NKG2A receptor) and perform non-viral insertion of a GD2-targeting chimeric antigen receptor (CAR) within NK cells isolated from human peripheral blood. Genome editing with CRISPR/Cas9 ribonucleoprotein complexes yields efficient genomic disruption of the KLRC1 gene with 98% knockout efficiency and specific knock-in of the GD2 CAR transgene as high as 23%, with minimal off-target activity as shown by CHANGE-Seq, in-out PCR, and next generation sequencing. KLRC1 -GD2 CAR NK cells display high viability and proliferation, as well as precise cellular targeting and potency against GD2 + human melanoma cells. Notably, KLRC1 -GD2 CAR NK cells overcome HLA-E-based inhibition by HLA-E-expressing, GD2 + melanoma cells. Using a single-step, virus-free genome editing workflow, this study demonstrates the feasibility of precisely disrupting inhibitory signaling within NK cells via CRISPR/Cas9 while expressing a CAR to generate potent allogeneic cell therapies against HLA-E + solid tumors.

Comparative Study of the Effect of Radiation Delivered by Lutetium-177 or Actinium-225 on Anti-GD2 Chimeric Antigen Receptor T Cell Viability and Functions

BACKGROUND AND PURPOSE

Chimeric antigen receptor (CAR) T cells have been relatively ineffective against solid tumors. Low-dose radiation which can be delivered to multiple sites of metastases by targeted radionuclide therapy (TRT) can elicit immunostimulatory effects. However, TRT has never been combined with CAR T cells against solid tumors in a clinical setting. This study investigated the effects of radiation delivered by Lutetium-177 (177Lu) and Actinium-225 (225Ac) on the viability and effector function of CAR T cells in vitro to evaluate the feasibility of such therapeutic combinations. After the irradiation of anti-GD2 CAR T cells with various doses of radiation delivered by 177Lu or 225Ac, their viability and cytotoxic activity against GD2-expressing human CHLA-20 neuroblastoma and melanoma M21 cells were determined by flow cytometry. The expression of the exhaustion marker PD-1, activation marker CD69 and the activating receptor NKG2D was measured on the irradiated anti-GD2 CAR T cells. Both 177Lu and 225Ac displayed a dose-dependent toxicity on anti-GD2 CAR T cells. However, radiation enhanced the cytotoxic activity of these CAR T cells against CHLA-20 and M21 irrespective of the dose tested and the type of radionuclide. No significant changes in the expression of PD-1, CD69 and NKG2D was noted on the CAR T cells following irradiation. Given a lower CAR T cell viability at equal doses and an enhancement of cytotoxic activity irrespective of the radionuclide type, 177Lu-based TRT may be preferred over 225Ac-based TRT when evaluating a potential synergism between these therapies in vivo against solid tumors.

Nonviral base editing of KCNJ13 mutation preserves vision in a model of inherited retinal channelopathy

Clinical genome editing is emerging for rare disease treatment, but one of the major limitations is the targeting of CRISPR editors' delivery. We delivered base editors to the retinal pigmented epithelium (RPE) in the mouse eye using silica nanocapsules (SNCs) as a treatment for retinal degeneration. Leber congenital amaurosis type 16 (LCA16) is a rare pediatric blindness caused by point mutations in the KCNJ13 gene, a loss of function inwardly rectifying potassium channel (Kir7.1) in the RPE. SNCs carrying adenine base editor 8e (ABE8e) mRNA and sgRNA precisely and efficiently corrected the KCNJ13W53X/W53X mutation. Editing in both patient fibroblasts (47%) and human induced pluripotent stem cell-derived RPE (LCA16-iPSC-RPE) (17%) showed minimal off-target editing. We detected functional Kir7.1 channels in the edited LCA16-iPSC-RPE. In the LCA16 mouse model (Kcnj13W53X/+ΔR), RPE cells targeted SNC delivery of ABE8e mRNA preserved normal vision, measured by full-field electroretinogram (ERG). Moreover, multifocal ERG confirmed the topographic measure of electrical activity primarily originating from the edited retinal area at the injection site. Preserved retina structure after treatment was established by optical coherence tomography (OCT). This preclinical validation of targeted ion channel functional rescue, a challenge for pharmacological and genomic interventions, reinforced the effectiveness of nonviral genome-editing therapy for rare inherited disorders.

Trichostatin A for Efficient CRISPR-Cas9 Gene Editing of Human Pluripotent Stem Cells

Genome-edited human-induced pluripotent stem cells (iPSCs) have broad applications in disease modeling, drug discovery, and regenerative medicine. Despite the development of clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system, the gene editing process is inefficient and can take several weeks to months to generate edited iPSC clones. We developed a strategy to improve the efficiency of the iPSC gene editing process via application of a small-molecule, trichostatin A (TSA), a Class I and II histone deacetylase inhibitor. We observed that TSA decreased global chromatin condensation and further resulted in increased gene-editing efficiency of iPSCs by twofold to fourfold while concurrently ensuring no increased off-target effects. The edited iPSCs could be clonally expanded while maintaining genomic integrity and pluripotency. The rapid generation of therapeutically relevant gene-edited iPSCs could be enabled by these findings.

Striatonigral distribution of a fluorescent reporter following intracerebral delivery of genome editors

Introduction: Targeted gene editing is proposed as a therapeutic approach for numerous disorders, including neurological diseases. As the brain is organized into neural networks, it is critical to understand how anatomically connected structures are affected by genome editing. For example, neurons in the substantia nigra pars compacta (SNpc) project to the striatum, and the striatum contains neurons that project to the substantia nigra pars reticulata (SNpr). Methods: Here, we report the effect of injecting genome editors into the striatum of Ai14 reporter mice, which have a LoxP-flanked stop cassette that prevents expression of the red fluorescent protein tdTomato. Two weeks following intracerebral delivery of either synthetic nanocapsules (NCs) containing CRISPR ribonucleoprotein targeting the tdTomato stop cassette or adeno-associated virus (AAV) vectors expressing Cre recombinase, the brains were collected, and the presence of tdTomato was assessed in both the striatum and SN. Results: TdTomato expression was observed at the injection site in both the NC- and AAV-treated groups and typically colocalized with the neuronal marker NeuN. In the SN, tdTomato-positive fibers were present in the pars reticulata, and SNpr area expressing tdTomato correlated with the size of the striatal genome edited area. Conclusion: These results demonstrate in vivo anterograde axonal transport of reporter gene protein products to the SNpr following neuronal genome editing in the striatum.

Role of Doppler Ultrasound in Diagnosis of Hepatocellular Carcinoma with Histopathological Correlation

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world and the leading cause (possibly third) of cancer mortality. In a present scenario, HCC displays a challenging clinical problem worldwide. Good-quality ultra sound with careful evaluation of the hepatobiliary system can be a screening examination for HCC in patients at risk. The aim of the study was to determine the diagnostic accuracy of the Doppler sonography for differentiation of hepatocellular carcinoma (HCC) from other focal liver lesions. It was a cross-sectional survey, conducted in the Department of Radiology& Imaging, Mymensingh Medical College, Mymensingh, Bangladesh from January 2017 to December 2018. A total of 70 patients with space occupying lesions on ultrasound were included in this study while pregnant women were excluded. All patients were examined by gray scale ultrasonography, color Doppler and FNAC. To visualize the blood flow, standard color Doppler sonography was used for each lesion. Within the lesions, pulsed Doppler samples were assessed whenever possible on the basis of pulsatile flow & finally resistive index (RI) of intra-tumoral and peritumoral arterial flow was studied. After evaluating by Doppler sonography (CDFI and Spectral analysis), FNAC was done and the specimen was sent to the Department of Pathology for Cytopathological examination. Cytopathology were assessed for confirmation of positive and negative cases of HCC. The detection rate of arterial flow in malignant tumors was 85.1% and in benign lesions were 30.4%. Doppler spectrum analysis showed that the resistive index in primary malignant tumors were 0.76±0.12 and in metastatic tumors were 0.80±0.12 and below 0.6 in benign lesions. The difference was significant (p<0.001). This difference was related with its Cytopathological report. The arterial flow identified by CDFI within the liver lesion with RI >0.6 can be regarded as a criterion of malignant tumors and RI<0.6 can be regarded as benign lesions. This study concluded that the combination of color Doppler flow imaging and RI are more useful in differential diagnosis of liver neoplasms.

Assessment of the Relationship between Non-motor features and Severity of Parkinson's Disease Patients in Bangladesh

Parkinson's disease (PD) is second most common neurodegenerative disorder after Alzheimer's disease that may present with both motor and non-motor symptoms (NMSs). Many of the ignored NMSs may potentiate further deterioration of the patient's quality of life (QoL). But there is scarcity of data regarding NMSs of PD patients and their relationship with the disease severity in Bangladesh. This study was aimed to investigate the frequency of NMSs and assess their debatable impact on the severity of PD patients in Bangladesh. This cross-sectional type of observational study was conducted in neurology department of Dhaka Medical College Hospital, Bangladesh from January 2012 to June 2013 which recruited 60 eligible PD patients. The PD patients and disease severity was demonstrated by UK Parkinson's Disease Society Brain Bank criteria for idiopathic PD and the Hoehn and Yahr scale respectively. Whereas, NMSs were demonstrated by the self-structured questionnaire which had encountered 30 common symptoms of PD. The mean age of our study cohort was found 57.88±10.56 years with male female ration 2:1. According to the Hoehn and Yahr (H & Y) severity scale 38.3%, 38.3%, 20.1% and 3.3% patients had been suffering from stage ?, stage II, stage III and stage ?V Parkinson's disease respectively. Irrespective of the severity of the PD the frequency of NMSs was nocturia (66.7%), sadness or blues (65.0%), memory disturbance (61.7%), anxiety (58.3%), insomnia (56.7%), orthostatic hypotension (55.0%), erectile dysfunction (50.0%), urinary urgency (46.7%), anhedonia (45.0%), olfactory disturbance (38.3%), constipation (38.3%), hyper or hypo sexuality (31.7%) and restless leg syndrome (31.7%). However, after head-to-head NMSs analysis, daytime dribbling of saliva (p=0.024), urinary urgency (p=0.036), nocturia (p=0.001), weight loss (p=0.001), anhedonia (p=0.027), excessive daytime sleepiness (p=0.024), insomnia (p=0.007), vivid dream (p=0.024), REM behavior disorder (p=0.010), restless leg syndrome/ periodic leg movements (p=0.043) had significantly been reported higher among the stage II PD patients than that of stage I patients. Whereas fall (p=0.001), dysphagia or choking (p=0.002), constipation (p=0.003), fecal incontinence (p=0.033), excessive daytime sleepiness (p=0.033), anxiety (p=0.036) and anhedonia (p=0.044) were significantly more prevalent among the advanced stage (III) than stage (II) PD patients. Mean total NMS increased significantly with PD severity based on H and Y staging with a mean NMSQ-T (Non-Motor Symptoms Questionnaire Test) of 5.43 in stage 1, 9.22 in stage 2, 13.75 in stage 3 and 17.0 in stage 4 (p=0.0001). This study revealed that there was high frequency of NMSs among the PD patients and most common symptoms were nocturia, sadness, memory impairment, anxiety, insomnia, orthostatic hypotension, erectile dysfunction, anhedonia, urinary urgency and constipation. Finally, the more advanced disease as indicated by a higher H&Y stage was associated with significantly higher number of reported NMSs.

Label-free in vitro assays predict the potency of anti-disialoganglioside chimeric antigen receptor T-cell products

BACKGROUND AIMS

Chimeric antigen receptor (CAR) T cells have demonstrated remarkable efficacy against hematological malignancies; however, they have not experienced the same success against solid tumors such as glioblastoma (GBM). There is a growing need for high-throughput functional screening platforms to measure CAR T-cell potency against solid tumor cells.

METHODS

We used real-time, label-free cellular impedance sensing to evaluate the potency of anti-disialoganglioside (GD2) targeting CAR T-cell products against GD2+ patient-derived GBM stem cells over a period of 2 days and 7 days in vitro. We compared CAR T products using two different modes of gene transfer: retroviral transduction and virus-free CRISPR-editing. Endpoint flow cytometry, cytokine analysis and metabolomics data were acquired and integrated to create a predictive model of CAR T-cell potency.

RESULTS

Results indicated faster cytolysis by virus-free CRISPR-edited CAR T cells compared with retrovirally transduced CAR T cells, accompanied by increased inflammatory cytokine release, CD8+ CAR T-cell presence in co-culture conditions and CAR T-cell infiltration into three-dimensional GBM spheroids. Computational modeling identified increased tumor necrosis factor α concentrations with decreased glutamine, lactate and formate as being most predictive of short-term (2 days) and long-term (7 days) CAR T cell potency against GBM stem cells.

CONCLUSIONS

These studies establish impedance sensing as a high-throughput, label-free assay for preclinical potency testing of CAR T cells against solid tumors.

Efficient in vivo neuronal genome editing in the mouse brain using nanocapsules containing CRISPR-Cas9 ribonucleoproteins

Genome editing of somatic cells via clustered regularly interspaced short palindromic repeats (CRISPR) offers promise for new therapeutics to treat a variety of genetic disorders, including neurological diseases. However, the dense and complex parenchyma of the brain and the post-mitotic state of neurons make efficient genome editing challenging. In vivo delivery systems for CRISPR-Cas proteins and single guide RNA (sgRNA) include both viral vectors and non-viral strategies, each presenting different advantages and disadvantages for clinical application. We developed non-viral and biodegradable PEGylated nanocapsules (NCs) that deliver preassembled Cas9-sgRNA ribonucleoproteins (RNPs). Here, we show that the RNP NCs led to robust genome editing in neurons following intracerebral injection into the healthy mouse striatum. Genome editing was predominantly observed in medium spiny neurons (>80%), with occasional editing in cholinergic, calretinin, and parvalbumin interneurons. Glial activation was minimal and was localized along the needle tract. Our results demonstrate that the RNP NCs are capable of safe and efficient neuronal genome editing in vivo.

Role of Transabdominal Ultrasonogram for Evaluation of Placental Maturity in Relation with Fetal Gestational Age

In this study our main goal is to evaluate the role of ultrasonography (USG) for determination of placental maturity and fetal gestational age. This cross-sectional study was done at the Department of Radiology and Imaging (USG section) Mymensingh Medical College and Hospital, Mymensingh from July 2008 to June 2010, where 60 patients included in this study, who was attending in the department of Radiology & Imaging for transabdominal ultrasonography with early and late pregnancy related complaints. In this study among the 60 patients, the youngest one was eighteen years and oldest one was thirty-nine years old age. Thirty five percent (35.0%) patients were from 26-30 years age group. About 33 patients out of 60(55.0%) were house wives. Most of the patients were presented with amenorrhea (65.0%) 39 out of 60. Among 60 patients, 20 patients (33.3%) were in gestational age within 12-28 weeks, 20 patients (33.3%) were in gestational age within 29-36 weeks and 20 patients (33.3%) were within >36 weeks gestational age. Among them, 20 patients (33.3%) had grade III placenta, 20 patients (33.3%) had grade II placenta, 12 patients (20%) had grade I placenta and 08 patients (13.3%) had grade 0 placenta. Out of 60 patients, 18 patients (30.0%) were in high risk group and 70.0% were normal. Six (6) patients (10.0%) suffered from HTN, 3 patients had RH negative (5.0%) blood group, 3(5.0%) patients suffered from APH, 3 patients suffer from DM and 3 from IUGR. In this study showed hypertension and IUGR had strong correlation with accelerated placental maturation. Maternal DM and Rh sensitization were associated with delayed maturation of the placenta. This study concludes that, USG appears to be the best imaging modality for the evaluation of placenta and its grading. USG is relatively less expensive and it is good considering the diagnostic accuracy in pregnancy profile. It is noninvasive procedure without any radiation hazards and better visualization of the lesion in different section, but this study is not a complete reflection of overall incidence and statistics regarding the ailment in our country. For this a more extensive study over a longer period covering different section of society is very much needed for better outcome.

Production and characterization of virus-free, CRISPR-CAR T cells capable of inducing solid tumor regression

BACKGROUND

Chimeric antigen receptor (CAR) T cells have demonstrated high clinical response rates against hematological malignancies (e.g., CD19+ cancers) but have shown limited activity in patients with solid tumors. Recent work showed that precise insertion of a CAR at a defined locus improves treatment outcomes in the context of a CD19 CAR; however, it is unclear if such a strategy could also affect outcomes in solid tumors. Furthermore, CAR manufacturing generally relies on viral vectors for gene delivery, which comprise a complex and resource-intensive part of the manufacturing supply chain.

METHODS

Anti-GD2 CAR T cells were generated using CRISPR/Cas9 within 9 days using recombinant Cas9 protein and nucleic acids, without any viral vectors. The CAR was specifically targeted to the T cell receptor alpha constant gene (TRAC). T cell products were characterized at the level of the genome, transcriptome, proteome, and secretome using CHANGE-seq, targeted next-generation sequencing, scRNA-seq, spectral cytometry, and ELISA assays, respectively. Functionality was evaluated in vivo in an NSG™ xenograft neuroblastoma model.

RESULTS

In comparison to retroviral CAR T cells, virus-free CRISPR CAR (VFC-CAR) T cells exhibit TRAC-targeted genomic integration of the CAR transgene, elevation of transcriptional and protein characteristics associated with a memory-like phenotype, and low tonic signaling prior to infusion arising in part from the knockout of the T cell receptor. On exposure to the GD2 target antigen, anti-GD2 VFC-CAR T cells exhibit specific cytotoxicity against GD2+ cells in vitro and induce solid tumor regression in vivo. VFC-CAR T cells demonstrate robust homing and persistence and decreased exhaustion relative to retroviral CAR T cells against a human neuroblastoma xenograft model.

CONCLUSIONS

This study leverages virus-free genome editing technology to generate CAR T cells featuring a TRAC-targeted CAR, which could inform manufacturing of CAR T cells to treat cancers, including solid tumors.

In situ autofluorescence lifetime assay of a photoreceptor stimulus response in mouse retina and human retinal organoids

Photoreceptors are the key functional cell types responsible for the initiation of vision in the retina. Phototransduction involves isomerization and conversion of vitamin A compounds, known as retinoids, and their recycling through the visual cycle. We demonstrate a functional readout of the visual cycle in photoreceptors within stem cell-derived retinal organoids and mouse retinal explants based on spectral and lifetime changes in autofluorescence of the visual cycle retinoids after exposure to light or chemical stimuli. We also apply a simultaneous two- and three-photon excitation method that provides specific signals and increases contrast between these retinoids, allowing for reliable detection of their presence and conversion within photoreceptors. This multiphoton imaging technique resolves the slow dynamics of visual cycle reactions and can enable high-throughput functional screening of retinal tissues and organoid cultures with single-cell resolution.

Label-Free Imaging to Track Reprogramming of Human Somatic Cells

The process of reprogramming patient samples to human-induced pluripotent stem cells (iPSCs) is stochastic, asynchronous, and inefficient, leading to a heterogeneous population of cells. In this study, we track the reprogramming status of patient-derived erythroid progenitor cells (EPCs) at the single-cell level during reprogramming with label-free live-cell imaging of cellular metabolism and nuclear morphometry to identify high-quality iPSCs. EPCs isolated from human peripheral blood of three donors were used for our proof-of-principle study. We found distinct patterns of autofluorescence lifetime for the reduced form of nicotinamide adenine dinucleotide (phosphate) and flavin adenine dinucleotide during reprogramming. Random forest models classified iPSCs with ∼95% accuracy, which enabled the successful isolation of iPSC lines from reprogramming cultures. Reprogramming trajectories resolved at the single-cell level indicated significant reprogramming heterogeneity along different branches of cell states. This combination of micropatterning, autofluorescence imaging, and machine learning provides a unique, real-time, and nondestructive method to assess the quality of iPSCs in a biomanufacturing process, which could have downstream impacts in regenerative medicine, cell/gene therapy, and disease modeling.

Controlling CRISPR with small molecule regulation for somatic cell genome editing

Biomedical research has been revolutionized by the introduction of many CRISPR-Cas systems that induce programmable edits to nearly any gene in the human genome. Nuclease-based CRISPR-Cas editors can produce on-target genomic changes but can also generate unwanted genotoxicity and adverse events, in part by cleaving non-targeted sites in the genome. Additional translational challenges for in vivo somatic cell editing include limited packaging capacity of viral vectors and host immune responses. Altogether, these challenges motivate recent efforts to control the expression and activity of different Cas systems in vivo. Current strategies utilize small molecules, light, magnetism, and temperature to conditionally control Cas systems through various activation, inhibition, or degradation mechanisms. This review focuses on small molecules that can be incorporated as regulatory switches to control Cas genome editors. Additional development of CRISPR-Cas-based therapeutic approaches with small molecule regulation have high potential to increase editing efficiency with less adverse effects for somatic cell genome editing strategies in vivo.

Single Cell Technologies to Dissect Heterogenous Immune Cell Therapy Products

Single cell tools have dramatically transformed the life sciences; concurrently, autologous and allogeneic immune cell therapies have recently entered the clinic. Here we discuss methods, applications, and considerations for single cell technologies in the context of immune cell manufacturing. Molecular heterogeneity can be profiled at the level of the genome, epigenome, transcriptome, proteome, metabolome, and antigen receptor repertoire, in isolation or in tandem through multi-omic approaches. Such data inform heterogeneity within cell products and can be linked to potency readouts and clinical data, with the ultimate goal of identifying Critical Quality Attributes to predict patient outcomes. Non-destructive approaches hold promise for monitoring cell state and analyzing the impacts of gene edits within engineered products. Destructive omics approaches could be combined with non-destructive technologies to predict therapeutic potency. These technologies are poised to redefine cell manufacturing toward rapid, cost-effective, and high-throughput methods to detect and respond to dynamic cell states.

Psychobiology of Stress and Adolescent Depression (PSY SAD) Study: Protocol overview for an fMRI-based multi-method investigation

Depression is a common, often recurrent disorder that causes substantial disease burden worldwide, and this is especially true for women following the pubertal transition. According to the Social Signal Transduction Theory of Depression, stressors involving social stress and rejection, which frequently precipitate major depressive episodes, induce depressive symptoms in vulnerable individuals in part by altering the activity and connectivity of stress-related neural pathways, and by upregulating components of the immune system involved in inflammation. To test this theory, we recruited adolescent females at high and low risk for depression and assessed their psychological, neural, inflammatory, and genomic responses to a brief (10 minute) social stress task, in addition to trait psychological and microbial factors affecting these responses. We then followed these adolescents longitudinally to investigate how their multi-level stress responses at baseline were related to their biological aging at baseline, and psychosocial and clinical functioning over one year. In this protocol paper, we describe the theoretical motivations for conducting this study as well as the sample, study design, procedures, and measures. Ultimately, our aim is to elucidate how social adversity influences the brain and immune system to cause depression, one of the most common and costly of all disorders.

Machine learning approach to measurement of criticism: The core dimension of expressed emotion

Expressed emotion (EE), a measure of the family's emotional climate, is a fundamental measure in caregiving research. A core dimension of EE is the level of criticism expressed by the caregiver to the care recipient, with a high level of criticism a marker of significant distress in the household. The Five-Minute Speech Sample (FMSS), the most commonly used brief measure of EE, requires time-consuming manual processing and scoring by a highly trained expert. In this study, we used natural language processing and supervised machine learning techniques to develop a fully automated framework to evaluate caregiver criticism level based on the verbatim transcript of the FMSS. The success of the machine learning algorithm was established by demonstrating that the classification of maternal caregivers as high versus low EE was consistent with the classification of these 298 maternal caregivers of adult children with schizophrenia using standard manual coding procedures, with area under the receiver operating characteristic curve (AUROC) of 0.76. Evidence of construct validity was established by demonstrating that maternal caregivers of adults with schizophrenia, who were classified as having a high level of criticism had higher levels of caregiver burden, reported that their child had more psychiatric symptoms and behaviors and perceived that their child had greater control over these symptoms and behaviors. Additionally, maternal caregivers who had high levels of criticism reported having a poorer quality of relationship with their child with schizophrenia than maternal caregivers low on criticism. Rapid measurement of criticism facilitates the incorporation of this dimension into research across a broad range of caregiving contexts. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Abstract 1552: Kinetics and potency of T cell and CAR-T cell mediated cytolysis of glioma stem cells

Glioblastoma (GBM) is an aggressive form of brain cancer that has no effective treatments and a prognosis of only 12-18 months. Immune effector T cells are a promising therapy due to their innate cytotoxicity. In addition, engineering chimeric antigen receptors (CAR) to target tumor-associated or neo-antigens can lend high specificity. The ability to assess the efficacy and potency of such T cell therapies in vitro at high throughputs is vital for the preclinical development of these promising therapies. Cellular impedance assays offer a sensitive, non-destructive, and label-free method to continuously monitor cancer cell proliferation and immune cell-mediated cytotoxicity in real-time, revealing not only the potency but also the kinetics of T cell killing. Here, we used co-culture to compare the cytolytic potency and kinetics of naïve activated T Cells and targeted GD2 CAR-T cells against glioma stem cells (GSC), a subpopulation of glioblastoma cells.

Patient-derived N08 GSCs were plated at 50k cells per well on a PEI and laminin-coated CytoView-Z 96-well plates, and their impedance was continuously monitored on the Maestro Z impedance platform (Axion BioSystems). After 48 hours, human naïve activated T Cells (ImmunoCult CD3/CD28 activation media) or GD2 CAR-T cells were added at varying effector:target ratios ranging from 0.1:1 to 10:1. Impedance and cytolysis were subsequently monitored for up to 7 days.

The addition of activated T Cells or GD2 CAR-T Cells resulted in cell swelling, followed by a decrease in impedance consistent with T cell-mediated lysis of GSCs. GD-2 CAR-T Cells resulted in a significantly higher percent cytolysis of GSCs compared to naïve activated T Cells after 7 days of exposure. In addition, the kill time 50, defined as the time to reach 50% cytolysis of target cells, was shorter for GD-2 CAR-T Cells compared to naïve activated T Cells.

Cytotoxic function was validated with subsequent flow cytometry and cytokine analysis. After 7 days in co-culture, GD2 CAR-T cells exhibited markers of chronic activation, including greater CD8 expression than CD4, upregulation of CD69 (33% of cells), and induction of GrB (70%). Initial exhaustion was suggested by expression of PD1 (80% cells) and LAG3 (35%), but not TIM3.

Overall, both naïve activated T-Cells and GD2 CAR-T Cells were effective for cytolysis of GSCs, with CAR-T exhibiting more efficient killing. CAR-T Cells engineered to target the GD2 antigen exhibited stronger potency and faster kinetics, suggesting greater clinical potential against glioblastoma.

Citation Format: Heather Brant Hayes, Meghan T. Logun, Stacie A. Chvatal, Katie Mueller, Nicole Piscopo, Amritava Das, Krishanu Saha, Daniel C. Millard, Lohitash Karumbaiah. Kinetics and potency of T cell and CAR-T cell mediated cytolysis of glioma stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1552.

A Rare Case of Polyorchidism: Sonographic and MR Evaluation of Four Testes

Polyorchidism is a rare congenital anomaly reported about 200 cases in the world text. A number of theories have been planned concerning the making of polyorchidism, but the real explanation is still not acknowledged. Here we are going to present a case study of polyorchidism. A 70 years old gentleman complained with left supernumerary testes in the left hemiscrotum. His left hemiscrotum was painless with mass. Polyorchidism without malignancy or any other concomitant features were revealed by both ultrasound and MRI examinations. In most cases the ultrasonograph alone is diagnostic. In complicated cases of polyorchidism MRI may provide additional information.

GD2 CAR-T Cells exhibit strong cytolytic potency against glioma stem cells

Glioblastoma (GBM) is an aggressive brain cancer without effective treatments. CAR-T cells targeted to tumor-associated antigens offer promise for treating GBM. Here, we used cellular impedance assays to compare the cytolytic potency and kinetics of conventional viral vs non-viral CRISPR engineered GD2 CAR-T cells against glioma stem cells (GSC), a subpopulation of glioblastoma cells.

Patient-derived N08 GSCs were plated at 50k cells/well on 96-well plates, and impedance was continuously monitored on the Maestro Z impedance platform (Axion BioSystems). GD2 CAR-T cells were engineered using either retroviral transduction (RV) or non-viral CRISPR editing (NV). At 48 hours, GD2 CAR-T cells were added at Effector:Target ratios of 0.1:1, 1:1, and 10:1. Comparisons were made to mCherry T cells (mCh) as a control. Impedance and cytolysis were monitored up to 7 days.

RV and NV GD2 CAR-T cells caused decreases in impedance consistent with T cell-mediated lysis of GSCs, whereas mCh T cells induced little change. NV CAR-T cells exhibited faster killing kinetics compared to RV CAR-T cells. The time to 50% cytolysis (KT50) was significantly shorter for NV vs RV CAR-T cells at 1:1 and 10:1 E:T ratios.

Cytotoxic function was validated with flow cytometry and cytokine analysis at 7 days. All T cells exhibited chronic activation measured by CD69 and CD137 upregulation. Importantly, NV CAR-T cells exhibited less exhaustion, as measured by PD1 and LAG3 expression.

Both RV and NV GD2 CAR-T cells effectively cytolyzed GSCs, with NV CAR-T cells exhibiting more potent and efficient killing. The high potency, fast kinetics, and reduced exhaustion of NV CRISPR GD2 CAR-T cells offer great clinical promise for treating GBM.

Integrating Biomaterials and Genome Editing Approaches to Advance Biomedical Science

The recent discovery and subsequent development of the CRISPR-Cas9 (clustered regularly interspaced short palindromic repeat-CRISPR-associated protein 9) platform as a precise genome editing tool have transformed biomedicine. As these CRISPR-based tools have matured, multiple stages of the gene editing process and the bioengineering of human cells and tissues have advanced. Here, we highlight recent intersections in the development of biomaterials and genome editing technologies. These intersections include the delivery of macromolecules, where biomaterial platforms have been harnessed to enable nonviral delivery of genome engineering tools to cells and tissues in vivo. Further, engineering native-like biomaterial platforms for cell culture facilitates complex modeling of human development and disease when combined with genome engineering tools. Deeper integration of biomaterial platforms in these fields could play a significant role in enabling new breakthroughs in the application of gene editing for the treatment of human disease.

Metal contaminations in sediment and associated ecological risk assessment of river Mahanadi, India

Mahanadi is one of the major rivers of peninsular India. Like other Indian rivers, it is contaminated with sewages, industrial discharges, and agricultural runoff. Thus, necessity was felt to monitor its pollution status. Present work was part of that program and aimed to assess the sediment contamination due to the trace metals Cd, Cr, Cu, Mn, Pb, and Zn during 2012-2015. Sediment pollution status and ecological risks were evaluated calculating contamination factor (CF), geo-accumulation (I_geo), pollution load index (PLI), potential ecological risk (EⁱR), etc. The recorded metal concentrations were Cd BDL of flame mode of AAS; Cr BDL - 73.9; Cu BDL - 44.4; Mn 37.2 - 1887.0; Pb BDL - 29.5; and Zn BDL - 92.5 mg kg^-1. As per US EPA guidelines, Cr concentrations at many locations were in the moderately polluted range. I_geo, CF, mC_d, PLI, and EⁱR indicated low pollution levels and low ecological risks due to the trace metals assessed. The sediment quality guidelines (SQGs) indicated that Cr and Cu concentrations exceeded (16% sample) the threshold effect concentrations and may occasionally exhibit adverse biological effects. The association of sediment organic matter, conductivity and content of Cu, and their grouping in component 1 of PCA revealed that the anthropogenic input was dominant and so also the component 2 where Cr exhibited moderately good correlation with organic matter. Cluster analysis of the sampling sites based on pollution status yielded 3 groups: relatively uncontaminated (S3, S4), low to moderately contaminated (S2), and moderately contaminated (S1, S5, S6) stretches.

Carbomer-based adjuvant elicits CD8 T-cell immunity by inducing a distinct metabolic state in cross-presenting dendritic cells

There is a critical need for adjuvants that can safely elicit potent and durable T cell-based immunity to intracellular pathogens. Here, we report that parenteral vaccination with a carbomer-based adjuvant, Adjuplex (ADJ), stimulated robust CD8 T-cell responses to subunit antigens and afforded effective immunity against respiratory challenge with a virus and a systemic intracellular bacterial infection. Studies to understand the metabolic and molecular basis for ADJ's effect on antigen cross-presentation by dendritic cells (DCs) revealed several unique and distinctive mechanisms. ADJ-stimulated DCs produced IL-1β and IL-18, suggestive of inflammasome activation, but in vivo activation of CD8 T cells was unaffected in caspase 1-deficient mice. Cross-presentation induced by TLR agonists requires a critical switch to anabolic metabolism, but ADJ enhanced cross presentation without this metabolic switch in DCs. Instead, ADJ induced in DCs, an unique metabolic state, typified by dampened oxidative phosphorylation and basal levels of glycolysis. In the absence of increased glycolytic flux, ADJ modulated multiple steps in the cytosolic pathway of cross-presentation by enabling accumulation of degraded antigen, reducing endosomal acidity and promoting antigen localization to early endosomes. Further, by increasing ROS production and lipid peroxidation, ADJ promoted antigen escape from endosomes to the cytosol for degradation by proteasomes into peptides for MHC I loading by TAP-dependent pathways. Furthermore, we found that induction of lipid bodies (LBs) and alterations in LB composition mediated by ADJ were also critical for DC cross-presentation. Collectively, our model challenges the prevailing metabolic paradigm by suggesting that DCs can perform effective DC cross-presentation, independent of glycolysis to induce robust T cell-dependent protective immunity to intracellular pathogens. These findings have strong implications in the rational development of safe and effective immune adjuvants to potentiate robust T-cell based immunity.

Design of efficacious somatic cell genome editing strategies for recessive and polygenic diseases

Compound heterozygous recessive or polygenic diseases could be addressed through gene correction of multiple alleles. However, targeting of multiple alleles using genome editors could lead to mixed genotypes and adverse events that amplify during tissue morphogenesis. Here we demonstrate that Cas9-ribonucleoprotein-based genome editors can correct two distinct mutant alleles within a single human cell precisely. Gene-corrected cells in an induced pluripotent stem cell model of Pompe disease expressed the corrected transcript from both corrected alleles, leading to enzymatic cross-correction of diseased cells. Using a quantitative in silico model for the in vivo delivery of genome editors into the developing human infant liver, we identify progenitor targeting, delivery efficiencies, and suppression of imprecise editing outcomes at the on-target site as key design parameters that control the efficacy of various therapeutic strategies. This work establishes that precise gene editing to correct multiple distinct gene variants could be highly efficacious if designed appropriately.

Human iPSC Modeling Reveals Mutation-Specific Responses to Gene Therapy in a Genotypically Diverse Dominant Maculopathy

Dominantly inherited disorders are not typically considered to be therapeutic candidates for gene augmentation. Here, we utilized induced pluripotent stem cell-derived retinal pigment epithelium (iPSC-RPE) to test the potential of gene augmentation to treat Best disease, a dominant macular dystrophy caused by over 200 missense mutations in BEST1. Gene augmentation in iPSC-RPE fully restored BEST1 calcium-activated chloride channel activity and improved rhodopsin degradation in an iPSC-RPE model of recessive bestrophinopathy as well as in two models of dominant Best disease caused by different mutations in regions encoding ion-binding domains. A third dominant Best disease iPSC-RPE model did not respond to gene augmentation, but showed normalization of BEST1 channel activity following CRISPR-Cas9 editing of the mutant allele. We then subjected all three dominant Best disease iPSC-RPE models to gene editing, which produced premature stop codons specifically within the mutant BEST1 alleles. Single-cell profiling demonstrated no adverse perturbation of retinal pigment epithelium (RPE) transcriptional programs in any model, although off-target analysis detected a silent genomic alteration in one model. These results suggest that gene augmentation is a viable first-line approach for some individuals with dominant Best disease and that non-responders are candidates for alternate approaches such as gene editing. However, testing gene editing strategies for on-target efficiency and off-target events using personalized iPSC-RPE model systems is warranted. In summary, personalized iPSC-RPE models can be used to select among a growing list of gene therapy options to maximize safety and efficacy while minimizing time and cost. Similar scenarios likely exist for other genotypically diverse channelopathies, expanding the therapeutic landscape for affected individuals.

Classification of T-cell activation via autofluorescence lifetime imaging

The function of a T cell depends on its subtype and activation state. Here, we show that the imaging of autofluorescence-lifetime signals from quiescent and activated T cells can be used to classify the cells. T cells isolated from human peripheral blood and activated in culture via a tetrameric antibody against the surface ligands CD2, CD3 and CD28 showed specific activation-state-dependent patterns of autofluorescence lifetime. Logistic-regression models and random-forest models classified T cells according to activation state with 97–99% accuracy, and according to activation state (quiescent or activated) and subtype (CD3⁺ CD8⁺ or CD3⁺ CD4⁺) with 97% accuracy. Autofluorescence-lifetime imaging could be used to non-destructively determine T-cell function.

Democratic Governance of Human Germline Genome Editing

An international regulatory commission convened by scientific academies is a premature and problematic approach to governing human germline genome editing. Given the complex, international landscape of genome editing and significant cross-national differences among regulatory cultures, deferring to a single commission to set the agenda for global governance raises troublesome questions of framing and representation. Rather, democratic governance on a global level demands a new mechanism for active, sustained reflection by scientists on their own practices, conducted in partnership with scholars from other disciplines, as well as public representatives from varied social, political, and religious backgrounds. To be legitimate, ideas of the right form of governance in this emerging and highly consequential area of research need to be opened up to a wider diversity of views and voices.

Genome engineering of induced pluripotent stem cells to manufacture natural killer cell therapies

Natural killer (NK) cells play a crucial role in host immunity by detecting cells that downregulate MHC class I presentation and upregulate stress ligands, as commonly seen in cancers. Current NK therapies using primary NK cells are prone to manufacturing issues related to expansion and storage. Alternative cell sources utilizing immortalized NK cell lines require irradiation and are dependent on systemic IL-2 administration, which has been associated with adverse effects. In contrast, NK cells differentiated from induced pluripotent stem cells (iPSC-NK cells) offer an off-the-shelf alternative that may overcome these bottlenecks. The development of a serum-free and feeder-free differentiation protocol allows for the manufacturing of clinically adaptable iPSC-NK cells that are equally as effective as primary NK cells and the NK-92 cell line for many indications. Moreover, genetic modifications targeting NK-mediated antibody-dependent cellular cytotoxicity capabilities, cytotoxicity, and checkpoint inhibitors may increase the therapeutic potential of iPSC-NK products. This review will highlight the current sources for NK therapies and their respective constraints, discuss recent developments in the manufacturing and genetic engineering of iPSC-NK cells, and provide an overview of ongoing clinical trials using NK cells.

Borderline serous ovarian neoplasm: case report of a diagnostic challenge in intraoperative frozen sections

Surface epithelial tumors of the ovary account for 25% of all ovarian neoplasms. When composed predominantly of fibrous stroma, with glands and cysts forming a minor component, their appearance on imaging is often complex; cystic- to solid-appearing masses often raise suspicion of a malignant tumor. An accurate frozen histopathological diagnosis of a benign cystadenofibroma of this tumor can facilitate appropriate surgical management. However, it is equally important to diagnose areas of borderline changes/malignancy arising in these tumors, particularly when large or complex surface and inner papillary areas with multilayering or stratification are seen microscopically. We present here a case of bilateral complex ovarian mass in a 68-year-old woman, which was equivocal for malignancy on radiology, per operative gross examination as well as on frozen section evaluation. It was finally diagnosed as a borderline serous tumor (BOT) in a cystadenofibroma on histopathological examination.

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Borderline tumors among surface epithelial tumors with a prominent stromal component are uncommon.

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Adhesions & bilaterality with a prominent stromal component result in radiological interpretation of a complex ovarian mass.

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The Risk of Malignancy Index is usually <200 if the CA125 is low.

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Intraoperative surgical decisions are based on frozen section examination which are challenging.

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A benign tumor diagnosis may results in inadequate surgery, additional interventions later and possible tumor spread.

A pH-responsive silica-metal-organic framework hybrid nanoparticle for the delivery of hydrophilic drugs, nucleic acids, and CRISPR-Cas9 genome-editing machineries

Efficient delivery of hydrophilic drugs, nucleic acids, proteins, and any combination thereof is essential for various biomedical applications. Herein, we report a straightforward, yet versatile approach to efficiently encapsulate and deliver various hydrophilic payloads using a pH-responsive silica-metal-organic framework hybrid nanoparticle (SMOF NP) consisting of both silica and zeolitic imidazole framework (ZIF). This unique SMOF NP offers a high loading content and efficiency, excellent stability, and robust intracellular delivery of a variety of payloads, including hydrophilic small molecule drugs (e.g., doxorubicin hydrochloride), nucleic acids (e.g., DNA and mRNA), and genome-editing machineries (e.g., Cas9-sgRNA ribonucleoprotein (RNP), and RNP together with donor DNA (e.g., RNP + ssODN)). The superior drug delivery/gene transfection/genome-editing efficiencies of the SMOF NP are attributed to its pH-controlled release and endosomal escape capabilities due to the proton sponge effect enabled by the imidazole moieties in the SMOF NPs. Moreover, the surface of the SMOF NP can be easily customized (e.g., PEGylation and ligand conjugation) via various functional groups incorporated into the silica component. RNP-loaded SMOF NPs induced efficient genome editing in vivo in murine retinal pigment epithelium (RPE) tissue via subretinal injection, providing a highly promising nanoplatform for the delivery of a wide range of hydrophilic payloads.

Status of pesticide residues in water, sediment, and fishes of Chilika Lake, India

Chilika Lake is the largest coastal lagoon in Asia and the second largest in the world covering an area of 1100 km² and spread over three districts of Odisha state of India. It is the first Indian wetland designated as a wetland of international importance under the Ramsar Convention in 1981. The lake ecosystem sustains large and diversified resources of plants and animals including fisheries. Pollution of the ecosystem caused by residues of pesticides originating from different sources was assessed through multiple sampling from 2012 to 2016 from three potential sites of contamination, viz., Palur Bridge, Daya River Estuary, and Makara River. Incidence of organochlorinated (OC) pesticide residues was noticed in about 25% water samples. HCH (α, γ&δ), DDD (op^|), DDE (op^|&pp.^|) and heptachlor were the OCs detected in concentration varying from 0.025 to 23.4 μg/l. None of the eight targeted synthetic pyrethroid (SP) pesticides was found in water, but among the organophosphates (OP), chlorpyrifos (0.019-2.73 μg/l), and dichlorvos (0.647 μg/l) were recorded. In sediment samples, residues of OC or OP pesticides were not present, but one SP pesticide was recorded. Fish samples were contaminated to the extent of 55%, mostly with residues of OCs and OPs and less with SPs. However, their concentrations were below the permissible limit, so there was no direct threat of health hazards to humans.

Tracking and Predicting Human Somatic Cell Reprogramming Using Nuclear Characteristics

Reprogramming of human somatic cells to induced pluripotent stem cells (iPSCs) generates valuable resources for disease modeling, toxicology, cell therapy, and regenerative medicine. However, the reprogramming process can be stochastic and inefficient, creating many partially reprogrammed intermediates and non-reprogrammed cells in addition to fully reprogrammed iPSCs. Much of the work to identify, evaluate, and enrich for iPSCs during reprogramming relies on methods that fix, destroy, or singularize cell cultures, thereby disrupting each cell's microenvironment. Here, we develop a micropatterned substrate that allows for dynamic live-cell microscopy of hundreds of cell subpopulations undergoing reprogramming while preserving many of the biophysical and biochemical cues within the cells' microenvironment. On this substrate, we were able to both watch and physically confine cells into discrete islands during the reprogramming of human somatic cells from skin biopsies and blood draws obtained from healthy donors. Using high-content analysis, we identified a combination of eight nuclear characteristics that can be used to generate a computational model to predict the progression of reprogramming and distinguish partially reprogrammed cells from those that are fully reprogrammed. This approach to track reprogramming in situ using micropatterned substrates could aid in biomanufacturing of therapeutically relevant iPSCs and be used to elucidate multiscale cellular changes (cell-cell interactions as well as subcellular changes) that accompany human cell fate transitions.

A biodegradable nanocapsule delivers a Cas9 ribonucleoprotein complex for in vivo genome editing

Delivery technologies for the CRISPR-Cas9 (CRISPR, clustered regularly interspaced short palindromic repeats) gene editing system often require viral vectors, which pose safety concerns for therapeutic genome editing1. Alternatively, cationic liposomal components or polymers can be used to encapsulate multiple CRISPR components into large particles (typically >100 nm diameter); however, such systems are limited by variability in the loading of the cargo. Here, we report the design of customizable synthetic nanoparticles for the delivery of Cas9 nuclease and a single-guide RNA (sgRNA) that enables the controlled stoichiometry of CRISPR components and limits the possible safety concerns in vivo. We describe the synthesis of a thin glutathione (GSH)-cleavable covalently crosslinked polymer coating, called a nanocapsule (NC), around a preassembled ribonucleoprotein (RNP) complex between a Cas9 nuclease and an sgRNA. The NC is synthesized by in situ polymerization, has a hydrodynamic diameter of 25 nm and can be customized via facile surface modification. NCs efficiently generate targeted gene edits in vitro without any apparent cytotoxicity. Furthermore, NCs produce robust gene editing in vivo in murine retinal pigment epithelium (RPE) tissue and skeletal muscle after local administration. This customizable NC nanoplatform efficiently delivers CRISPR RNP complexes for in vitro and in vivo somatic gene editing.

Data-driven phenotype discovery of FMR1 premutation carriers in a population-based sample

The impact of the FMR1 premutation on human health is the subject of considerable controversy. A fundamental unanswered question is whether carrying the premutation allele is directly correlated with clinical phenotypes. A challenging problem in past genotype-phenotype studies of the FMR1 premutation is ascertainment bias, which could lead to invalid research conclusions and negatively affect clinical practice. Here, we created the first population-based FMR1-informed biobank to find the pattern of health characteristics in premutation carriers. Our extensive phenotyping shows that premutation carriers experience a clinical profile that is significantly different from controls and is evident throughout adulthood. Comprehensive understanding of the clinical risk associated with this genetic variant is critical for premutation carriers, their families, and clinicians and has important implications for public health.

Multi-cellular engineered living systems: building a community around responsible research on emergence

Ranging from miniaturized biological robots to organoids, multi-cellular engineered living systems (M-CELS) pose complex ethical and societal challenges. Some of these challenges, such as how to best distribute risks and benefits, are likely to arise in the development of any new technology. Other challenges arise specifically because of the particular characteristics of M-CELS. For example, as an engineered living system becomes increasingly complex, it may provoke societal debate about its moral considerability, perhaps necessitating protection from harm or recognition of positive moral and legal rights, particularly if derived from cells of human origin. The use of emergence-based principles in M-CELS development may also create unique challenges, making the technology difficult to fully control or predict in the laboratory as well as in applied medical or environmental settings. In response to these challenges, we argue that the M-CELS community has an obligation to systematically address the ethical and societal aspects of research and to seek input from and accountability to a broad range of stakeholders and publics. As a newly developing field, M-CELS has a significant opportunity to integrate ethically responsible norms and standards into its research and development practices from the start. With the aim of seizing this opportunity, we identify two general kinds of salient ethical issues arising from M-CELS research, and then present a set of commitments to and strategies for addressing these issues. If adopted, these commitments and strategies would help define M-CELS as not only an innovative field, but also as a model for responsible research and engineering.

CRISPR/Cas9 editing of APP C-terminus attenuates β-cleavage and promotes α-cleavage

CRISPR/Cas9 guided gene-editing is a potential therapeutic tool, however application to neurodegenerative disease models has been limited. Moreover, conventional mutation correction by gene-editing would only be relevant for the small fraction of neurodegenerative cases that are inherited. Here we introduce a CRISPR/Cas9-based strategy in cell and animal models to edit endogenous amyloid precursor protein (APP) at the extreme C-terminus and reciprocally manipulate the amyloid pathway, attenuating APP-β-cleavage and Aβ production, while up-regulating neuroprotective APP-α-cleavage. APP N-terminus and compensatory APP-homologues remain intact, with no apparent effects on neurophysiology in vitro. Robust APP-editing is seen in human iPSC-derived neurons and mouse brains with no detectable off-target effects. Our strategy likely works by limiting APP and BACE-1 approximation, and we also delineate mechanistic events that abrogates APP/BACE-1 convergence in this setting. Our work offers conceptual proof for a selective APP silencing strategy.

Gene editing strategies are typically designed to correct mutant genes, but most neurodegenerative diseases are sporadic. Here the authors describe a strategy to selectively edit the C-terminus of APP and attenuate amyloid-β production, while upregulating neuroprotective α-cleavage.

Versatile Redox-Responsive Polyplexes for the Delivery of Plasmid DNA, Messenger RNA, and CRISPR-Cas9 Genome-Editing Machinery

Gene therapy holds great promise for the treatment of many diseases, but clinical translation of gene therapies has been slowed down by the lack of safe and efficient gene delivery systems. Here, we report two versatile redox-responsive polyplexes (i.e., cross-linked and non-crosslinked) capable of efficiently delivering a variety of negatively charged payloads including plasmid DNA (DNA), messenger RNA, Cas9/sgRNA ribonucleoprotein (RNP), and RNP-donor DNA complexes (S1mplex) without any detectable cytotoxicity. The key component of both types of polyplexes is a cationic poly( N, N'-bis(acryloyl)cystamine- co-triethylenetetramine) polymer [a type of poly( N, N'-bis(acryloyl)cystamine-poly(aminoalkyl)) (PBAP) polymer] containing disulfide bonds in the backbone and bearing imidazole groups. This composition enables efficient encapsulation, cellular uptake, controlled endo/lysosomal escape, and cytosolic unpacking of negatively charged payloads. To further enhance the stability of non-crosslinked PBAP polyplexes, adamantane (AD) and β-cyclodextrin (β-CD) were conjugated to the PBAP-based polymers. The cross-linked PBAP polyplexes formed by host-guest interaction between β-CD and AD were more stable than non-crosslinked PBAP polyplexes in the presence of polyanionic polymers such as serum albumin, suggesting enhanced stability in physiological conditions. Both cross-linked and non-crosslinked polyplexes demonstrated either similar or better transfection and genome-editing efficiencies, and significantly better biocompatibility than Lipofectamine 2000, a commercially available state-of-the-art transfection agent that exhibits cytotoxicity.

Response to Beriain

Professor Beriain's criticism rests on a narrow conception of human dignity pertaining only to individuals within a society. The social relations and norms that underpin human dignity are treated as mere group interests that are secondary to the dignity of the individual. In our view, this is a false dichotomy.

The potential of CAR T therapy for relapsed or refractory pediatric and young adult B-cell ALL

Recent advancements in immunooncology have resulted in the generation of novel therapies such as chimeric antigen receptor (CAR) T cells, which have revolutionized the treatment of pediatric patients with relapsed or refractory B-cell acute lymphoblastic leukemia. The journey of tisagenlecleucel (formerly CTL019) from early preclinical success to the US Food and Drug Administration approval is summarized in this review. Strategies that are currently being investigated to improve the efficacy and safety profile of CAR T-cells are also explored, as well as the factors contributing to the present state of patient access to CAR T therapy.

Increasing the precision of gene editing in vitro, ex vivo, and in vivo

New gene editing tools like CRISPR-Cas9 enable precision genome engineering within cell lines, primary cells, and model organisms, with some formulations now entering the clinic. "Precision" applies to various aspects of gene editing, and can be tailored for each application. Here we review recent advances in four types of precision in gene editing: 1) increased DNA cutting precision (e.g., on-target:off-target nuclease specificity), 2) increased on-target knock-in of sequence variants and transgenes (e.g., increased homology-directed repair), 3) increased transcriptional control of edited genes, and 4) increased specificity in delivery to a specific cell or tissue. Design of next-generation gene and cell therapies will likely exploit a combination of these advances.

Building Capacity for a Global Genome Editing Observatory: Institutional Design

A new infrastructure is urgently needed at the global level to facilitate exchange on key issues concerning genome editing. We advocate the establishment of a global observatory to serve as a center for international, interdisciplinary, and cosmopolitan reflection. This article is the second of a two-part series.

Building Capacity for a Global Genome Editing Observatory: Institutional Design

A new infrastructure is urgently needed at the global level to facilitate exchange on key issues concerning genome editing. We advocate the establishment of a global observatory to serve as a center for international, interdisciplinary, and cosmopolitan reflection. This article is the second of a two-part series.