Tertiary lymphoid structures sustain cutaneous B cell activity in hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic skin condition affecting approximately 1% of the US population. HS skin lesions are highly inflammatory and characterized by a large immune infiltrate. While B cells and plasma cells comprise a major component of this immune milieu, the biology and the contribution of these cells in HS pathogenesis are unclear. We aimed to investigate the dynamics and microenvironmental interactions of B cells within cutaneous HS lesions. Combining histological analysis, single-cell RNA sequencing, and spatial transcriptomics profiling of HS lesions, we defined the tissue microenvironment relative to B cell activity within this disease. Our findings identified tertiary lymphoid structures (TLSs) within HS lesions and described organized interactions among T cells, B cells, antigen-presenting cells, and skin stroma. We found evidence that B cells within HS TLSs actively underwent maturation, including participation in germinal center reactions and class switch recombination. Moreover, skin stroma and accumulating T cells were primed to support the formation of TLSs and facilitate B cell recruitment during HS. Our data definitively demonstrated the presence of TLSs in lesional HS skin and point to ongoing cutaneous B cell maturation through class switch recombination and affinity maturation during disease progression in this inflamed nonlymphoid tissue.

Abstract 432: Mechanisms of acquired resistance to ARV-471, a novel PROTAC® estrogen receptor degrader

ARV-471 is an orally bioavailable cereblon (CRBN)-based PROteolysis-TArgeting Chimera (PROTAC®) small molecule that demonstrates superior ER degradation and anti-tumor activity compared to fulvestrant in endocrine sensitive and resistant xenograft models and has shown significant ER degradation and promising clinical benefit in late-line ER-positive breast cancer patients. Innate and acquired drug resistance limits the response to and durability of many cancer therapies. To identify potential mechanisms of resistance to ARV-471, we generated ARV-471-resistant MCF7 cell lines which were then characterized using DNA, RNA and functional proteomic profiling. Acquired resistance to ARV-471 was associated with downregulation of ER protein expression and signaling and upregulation of HER family (EGFR, HER2, HER3) and MAPK/AKT signaling. NRAS copy number gain was also observed, which was accompanied by increased NRAS expression. Although EGFR, HER2 and HER3 expression and activation were upregulated, no corresponding genomic alterations were observed in resistant cells. Importantly, we show that NRAS and EGFR overexpression in MCF7 cells conferred resistance to ARV-471 in vitro. Furthermore, ARV-471-resistant cells with HER pathway upregulation were sensitive to EGFR and pan-HER inhibitors. Unlike recent reports indicating the association of E3 ligase alterations with PROTAC resistance, CRBN mutations/loss were not detected, nor were ESR1 mutations. CRBN knockout in ER+ breast cancer cells did not confer resistance to ARV-471, consistent with ARV-471 possessing ER antagonist activity independent of its degrader activity. Together, these data suggest that acquired resistance to ARV-471 may be associated with alterations within Receptor Tyrosine Kinase/MAPK signaling pathways rather than ER signaling or E3 ligase machinery.

Citation Format: Jessica Teh, Shannon Bessonett, Wendy Wu, Christopher Kuhlberg, Alissa Wynne, Sean Landrette, Monica Andreoli, Elizabeth Bortolon, Jennifer Pizzano, Richard Gedrich, Ian Taylor. Mechanisms of acquired resistance to ARV-471, a novel PROTAC® estrogen receptor degrader [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 432.

Abstract 3075: Enhanced efficacy of ARV-471, a novel PROTAC® estrogen receptor degrader, in combination with targeted agents in estrogen receptor-positive (ER+) breast cancer models

ARV-471 is a selective, orally bioavailable PROteolysis-TArgeting Chimera (PROTAC®) small molecule that induces wild-type and mutant estrogen receptor (ER) alpha degradation via the ubiquitin-proteasome system. ARV-471 demonstrates superior ER degradation and antitumor activity compared to fulvestrant in endocrine sensitive and resistant xenograft models and has shown significant ER degradation and promising clinical benefit in late-line ER+ breast cancer patients. Dual pathway inhibition combining ER targeting agents with CDK4/6 or PIK3CA/mTOR pathway inhibitors is now a central strategy for treatment of advanced ER+ breast cancer. However, resistance to aromatase inhibitors resulting from ESR1 gene mutations, suboptimal ER degradation and the intramuscular route of administration of fulvestrant underscore a need for superior orally bioavailable endocrine therapy backbones for these combinations. Here, we assessed the effects of ARV-471 in combination with CDK4/6 or PIK3CA/mTOR pathway inhibitors in preclinical models of ER+ breast cancer. In vitro studies revealed evidence of synergistic interactions between ARV-471 and the CDK4/6 inhibitors abemaciclib and ribociclib, the mTOR inhibitor everolimus, or the PIK3CA inhibitors alpelisib and inavolisib in ER+ breast cancer cells. Evidence of synergistic effects between ARV-471 and everolimus was also observed in ER+ breast cancer cells expressing ER Y537S or D538G mutations. ARV-471 in combination with CDK4/6, PIK3CA or mTOR inhibitors led to tumor regressions in MCF7 xenografts when compared to single agents alone. ARV-471 also displayed greater anti-tumor activity in combination with abemaciclib, ribociclib or inavolisib than that observed with fulvestrant in combination with these agents. Taken together, these data suggest the potential utility of ARV-471 as a combination partner for clinically relevant targeted agents for treatment of early and late-stage ER+ disease.

Citation Format: Jessica Teh, Elizabeth Bortolon, Jennifer Pizzano, Melissa Pannone, Sean Landrette, Richard Gedrich, Ian Taylor. Enhanced efficacy of ARV-471, a novel PROTAC® estrogen receptor degrader, in combination with targeted agents in estrogen receptor-positive (ER+) breast cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3075.

Tertiary Lymphoid Structures Sustain Cutaneous B cell Activity in Hidradenitis Suppurativa

Background

Hidradenitis suppurativa (HS) skin lesions are highly inflammatory and characterized by a large immune infiltrate. While B cells and plasma cells comprise a major component of this immune milieu the biology and contribution of these cells in HS pathogenesis is unclear.

Objective

We aimed to investigate the dynamics and microenvironmental interactions of B cells within cutaneous HS lesions.

Methods

We combined histological analysis, single-cell RNA-sequencing (scRNAseq), and spatial transcriptomic profiling of HS lesions to define the tissue microenvironment relative to B cell activity within this disease.

Results

Our findings identify tertiary lymphoid structures (TLS) within HS lesions and describe organized interactions between T cells, B cells, antigen presenting cells and skin stroma. We find evidence that B cells within HS TLS actively undergo maturation, including participation in germinal center reactions and class switch recombination. Moreover, skin stroma and accumulating T cells are primed to support the formation of TLS and facilitate B cell recruitment during HS.

Conclusion

Our data definitively demonstrate the presence of TLS in lesional HS skin and point to ongoing cutaneous B cell maturation through class switch recombination and affinity maturation during disease progression in this inflamed non-lymphoid tissue.

Nature-positive goals for an organization's food consumption

Organizations are increasingly committing to biodiversity protection targets with focus on 'nature-positive' outcomes, yet examples of how to feasibly achieve these targets are needed. Here we propose an approach to achieve nature-positive targets with respect to the embodied biodiversity impacts of an organization's food consumption. We quantify these impacts using a comprehensive database of life-cycle environmental impacts from food, and map exploratory strategies to meet defined targets structured according to a mitigation and conservation hierarchy. By considering the varying needs and values across the organization's internal community, we identify a range of targeted approaches towards mitigating impacts, which balance top-down and bottom-up actions to different degrees. Delivering ambitious nature-positive targets within current constraints will be challenging, particularly given the need to mitigate cumulative impacts. Our results evidence that however committed an organization is to being nature positive in its food provision, this is unachievable in the absence of systems change.

Causes of Mortality and Profile of Spontaneous Tumors in Young CD-1 Mice

A retrospective study was performed to establish the causes of mortality and incidence patterns of tumors in young (<50 weeks) control CD-1® mice from Charles River Laboratories. Tumor incidences (fatal and nonfatal) and nonneoplastic causes of death observed during the first 50 weeks of the study were collected from 48 thirteen-week toxicity studies conducted between 2009 and 2018 and from 43 carcinogenicity studies conducted between 2005 and 2018. Thirteen-week studies had a mortality rate of 8/620 (1.3%) in males and 4/620 (0.65%) in females. The major factors contributing to death were integument lesions in males (3/8) and experimental procedure-related injuries in females (3/4). All tumors recorded were nonfatal. Bronchiolo-alveolar adenoma was the commonest tumor with the same incidence in both males and females (4/620, 0.65%); a single lymphoma (0.16%) and uterine leiomyosarcoma (1/620 0.16%) were reported in females. The mortality rates of males and females that died or were euthanized during the first 50 weeks in carcinogenicity studies were 192/2830 (6.8%) and 198/2830 (7%), respectively. The most common fatal tumor in this age group was lymphoma in both sexes, with an incidence of 18/192 (9.3%) and 41/198 (20.7%) in males and females, respectively. In males tumors were responsible for fewer deaths than in females (17% vs. 32.3%). The major nonneoplastic causes of death or moribundity were cutaneous lesions (44/192, 22.9%), and obstructive uropathy (39/192, 20.3%) in males, and chronic progressive nephropathy (40/198, 20.2%) in females. Only minor differences were evident compared to a similar study performed 15 years ago; these might reflect changes in terminology and diagnostic criteria, and stricter animal welfare endpoints.

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND): Non-proliferative and Proliferative Lesions of the Non-human Primate (M. fascicularis)

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions Project (www.toxpath.org/inhand.asp) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in most tissues and organs from the nonhuman primate used in nonclinical safety studies. Some of the lesions are illustrated by color photomicrographs. The standardized nomenclature presented in this document is also available electronically on the internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions as well as lesions induced by exposure to test materials. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature for lesions in laboratory animals will provide a common language among regulatory and scientific research organizations in different countries and increase and enrich international exchanges of information among toxicologists and pathologists.

Inter-laboratory performance of ICE histopathology scoring to identify UN GHS Category 1 surfactants and non-extreme pH detergents

The inter-laboratory performance of Isolated Chicken Eye (ICE) histopathology scoring was assessed for predicting EU CLP/UN GHS Cat. 1 surfactants. Furthermore, the predictive capacity of ICE histopathology was evaluated for the combined dataset of surfactants and existing data for non-extreme pH (2 < pH < 11.5) detergents. Use of ICE histopathology led to increased sensitivity compared to the ICE test method alone for surfactants. When combined with the existing dataset of detergents, use of histopathology in addition to the standard ICE test method decreased the false negative rates from 64% (14/22) to 27% (6/22); increased accuracy from 53% (16/30) to 77% (23/30); and led to acceptable level of false positives (from 0/8 to 1/8 (12.5%). Moreover, good reproducibility of ICE histopathology predictions conducted on the same slides was found between pathologists and peer-reviewers from three independent laboratories (10/12 or 83%) and over time. Use of ICE histopathology was therefore found suitable to predict EU CLP/UN GHS Cat. 1 surfactants and non-extreme pH detergents. In addition, appropriate reproducibility of ICE histopathology was found, provided that i) an internal peer-review system was in place; ii) original slides were assessed to enable evaluation of three dimensional effects; and iii) appropriate training and proficiency appraisal were conducted.

Midline versus anterolateral incisions for total knee arthroplasty-a systematic review and analysis of the angiosomes of the knee

INTRODUCTION

The most common incision for total knee arthroplasty is the anterior midline incision; however, it is commonly associated with lateral knee numbness, kneeling difficulties and restricted flexion range. We sought to review the literature regarding the neurovascular supply and angiosomes over the anterior knee, and evaluate the anterolateral incision as a viable alternative for knee arthroplasty.

METHODS

A systematic review of the literature was performed searching PUBMED, MEDLINE and EMBASE to evaluate the incisions available for total knee arthroplasty with respect to neurological function, kneeling ability and complications.

RESULTS

Ten studies were identified evaluating midline or anterolateral incisions for total knee arthroplasty, with a total of 664 knees for analysis. Mean patient age was 68 years (45-88), and average length of followup was 1 year. A total of 586 had an anterior midline incision and 78 had an anterolateral incision. A total of 62% of anterior midline incisions sustained altered sensation compared to 15% (12/78) of anterolateral incisions (p < 0.0001). Incision length was similar in both groups (19.8 cm midline vs. 20.8 cm anterolateral). Wound dehiscence was not significantly different between the two groups being 8.3% for midline incisions, and 2.5% for anterolateral incisions (p = 0.153). Kneeling ability was reported in two studies which reported an improved ability to kneel with an anterolateral incision.

CONCLUSIONS

The lateral parapatellar incision respects the neurovascular anatomy of the knee and offers a significant reduction in sensory changes, better kneeling ability and similar rates of wound problems to a standard midline incision and should be considered as a viable alternative for knee arthroplasty.

Single cell multiomic analysis of T cell exhaustion in vitro

T-cell activation is a key step in the amplification of an immune response. Over the course of an immune response, cells may be chronically stimulated, with some proportion becoming exhausted; an enormous number of molecules are involved in this process. There remain a number of questions about the process, namely: 1) what degree of heterogeneity and plasticity do T-cells exhibit during stimulation? 2) how many unique cell states define chronic stimulation? and 3) what markers discriminate activated from exhausted cells? We addressed these questions by performing single-cell multiomic analysis to simultaneously measure expression of 38 proteins and 399 genes in human T cells expanded in vitro. This approach allowed us to study - with unprecedented depth - how T cells change over the course of chronic stimulation. Comprehensive immunophenotypic and transcriptomic analysis at day 0 enabled a refined characterization of T-cell maturational states and the identification of a donor-specific subset of terminally differentiated T-cells that would have been otherwise overlooked using canonical cell classification schema. As expected, activation downregulated naïve-cell markers and upregulated effector molecules, proliferation regulators, co-inhibitory and co-stimulatory receptors. Our deep kinetic analysis further revealed clusters of proteins and genes identifying unique states of activation, defined by markers temporarily expressed upon 3 days of stimulation (PD-1, CD69, LTA), markers constitutively expressed throughout chronic activation (CD25, GITR, LGALS1), and markers uniquely up-regulated upon 14 days of stimulation (CD39, ENTPD1, TNFDF10); expression of these markers could be associated with the emergence of short-lived cell types. Notably, different ratios of cells expressing activation or exhaustion markers were measured at each time point. These data reveal the high heterogeneity and plasticity of chronically stimulated T cells. Our study demonstrates the power of a single-cell multiomic approach to comprehensively characterize T-cells and to precisely monitor changes in differentiation, activation, and exhaustion signatures during cell stimulation.

Progressive Cellular Senescence Mediates Renal Dysfunction in Ischemic Nephropathy

BACKGROUND

Peripheral vascular diseases may induce chronic ischemia and cellular injury distal to the arterial obstruction. Cellular senescence involves proliferation arrest in response to stress, which can damage neighboring cells. Renal artery stenosis (RAS) induces stenotic-kidney dysfunction and injury, but whether these arise from cellular senescenceand their temporal pattern remain unknown.

METHODS

Chronic renal ischemia was induced in transgenic INK-ATTAC and wild type C57BL/6 mice by unilateral RAS, and kidney function (in vivo micro-MRI) and tissue damage were assessed. Mouse healthy and stenotic kidneys were analyzed using unbiased single-cell RNA-sequencing. To demonstrate translational relevance, cellular senescence was studied in human stenotic kidneys.

RESULTS

Using intraperitoneal AP20187 injections starting 1, 2, or 4 weeks after RAS, selective clearance of cells highly expressing p16^Ink4a attenuated cellular senescence and improved stenotic-kidney function; however, starting treatment immediately after RAS induction was unsuccessful. Broader clearance of senescent cells, using the oral senolytic combination dasatinib and quercetin, in C57BL/6 RAS mice was more effective in clearing cells positive for p21 (Cdkn1a) and alleviating renal dysfunction and damage. Unbiased, single-cell RNA sequencing in freshly dissociated cells from healthy and stenotic mouse kidneys identified stenotic-kidney epithelial cells undergoing both mesenchymal transition and senescence. As in mice, injured human stenotic kidneys exhibited cellular senescence, suggesting this process is conserved.

CONCLUSIONS

Maladaptive tubular cell senescence, involving upregulated p16 (Cdkn2a), p19 (Cdkn2d), and p21 (Cdkn1a) expression, is associated with renal dysfunction and injury in chronic ischemia. These findings support development of senolytic strategies to delay chronic ischemic renal injury.

Development of clinical competence - a longitudinal survey of nurse practitioner students

BACKGROUND

In order to achieve a sustainable standard of advanced clinical competence for nurse practitioners leading to a credible role, it is important to investigate the development of clinical competence among nurse practitioner students.

AIM

The aim of the present study is to analyse the development of nurse practitioner students' self-assessed clinical competence from the beginning of their education to after completion of their clinical studies.

DESIGN

The study involved the application of a longitudinal survey design adhering to STROBE guidelines.

METHODS

The participants consisted of 36 registered nurses from a nurse practitioner programme at a Norwegian university. The Professional Nurse Self-Assessment Scale II was used for data collection during the period August 2015 to May 2020.

RESULTS

The students developed their clinical competence the most for direct clinical practice. Our findings are inconclusive in terms of whether the students developed clinical competence regarding consultation, coaching and guidance, and collaboration. However, they do indicate a lack of development in some aspects of clinical leadership. The students with the lowest level of clinical competence developed their clinical competence regarding direct clinical practice significantly more than the students with the highest level of clinical competence. The differences between students with high and low levels of clinical competence were levelled out during their education. Thus, the students as a whole became a more homogenous group after completion of their clinical studies. Previous work experience in primary healthcare was a statistically significant, yet minor, predictor of the development of clinical competence.

CONCLUSION

Our findings indicate that the students developed their clinical competence for direct clinical practice in accordance with the intended learning outcomes of the university's Master's programme and international standards for nurse practitioners. It is imperative that the clinical field supports nurse practitioners by facilitating extended work-task fits that are appropriate to their newly developed clinical competence. We refrain from concluding with a recommendation that prior clinical work experience should be an entry requirement for nurse practitioner programmes. However, we recommend an evaluation of the nurse practitioner education programme with the aim of investigating whether the curriculum meets the academic standards of clinical leadership expected in advanced level of nursing.

Abstract 43: Discovery of ARV-110, a first in class androgen receptor degrading PROTAC for the treatment of men with metastatic castration resistant prostate cancer

Prostate cancer is the second leading cause of cancer death in men in the United States. The androgen receptor (AR) plays critical roles in both early disease and advanced prostate cancer. Current therapeutic approaches targeting the androgen/AR axis are initially effective, but castration resistant prostate cancer (CRPC) inevitably develops. CRPC is tightly linked with increased AR activity via gene overexpression, amplification, and gain-of-function mutations. To address these mechanisms of AR-dependent prostate tumor growth, we have developed a novel therapeutic agent, ARV-110, a proteolysis targeting chimera (PROTAC®) that induces a protein-protein interaction between the AR and E3 ubiquitin ligase complexes, leading to the ubiquitination of AR and its subsequent degradation via the proteasome. In vitro, ARV-110 robustly degrades AR in various prostate cancer cell lines with a half-maximal degradation concentration (DC50) of ~1 nM. Whole cell lysate proteomics and ubiquitin proteomics demonstrated high selectivity for AR in VCaP cells. ARV-110 potently downregulates androgen responsive genes, inhibits proliferation and induces apoptosis in AR dependent prostate cancer cells. In vivo, ARV-110 is orally bioavailable and robustly degrades AR with a &gt;90% observed maximum degradation (Dmax) at efficacious doses. ARV-110 significantly and dose-dependently inhibits tumor growth in murine LNCaP and VCaP xenograft models, including enzalutamide-resistant VCaP and enzalutamide-insensitive patient-derived xenograft models. These preclinical data supported the clinical development of ARV-110 for the treatment of men with metastatic CRPC. The discovery, chemical structure and initial clinical data of ARV-110 will be presented

Citation Format: Lawrence B. Snyder, Taavi K. Neklesa, Xin Chen, Hanqing Dong, Caterina Ferraro, Deborah A. Gordon, Jennifer Macaluso, Jennifer Pizzano, Jing Wang, Ryan R. Willard, Nicholas Vitale, Ron Peck, Marcia Dougan Moore, Craig M. Crews, John Houston, Andrew P. Crew, Ian Taylor. Discovery of ARV-110, a first in class androgen receptor degrading PROTAC for the treatment of men with metastatic castration resistant prostate cancer [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 43.

Abstract 44: The discovery of ARV-471, an orally bioavailable estrogen receptor degrading PROTAC for the treatment of patients with breast cancer

ARV-471, an estrogen receptor (ER) alpha PROTAC® protein degrader, is a hetero-bifunctional molecule that facilitates the interactions between estrogen receptor alpha and an intracellular E3 ligase complex, leading to the ubiquitylation and subsequent degradation of estrogen receptors via the proteasome. ARV-471 robustly degrades ER in ER-positive breast cancer cell lines with a half-maximal degradation concentration (DC50) of ~ 1 nM. PROTAC® mediated ER degradation decreases the expression of classically regulated ER-target genes and inhibits cell proliferation of ER-dependent cell lines (MCF7, T47D). Additionally, ARV-471 degrades clinically relevant ESR1 variants (Y537S and D538G) and inhibits growth of cell lines expressing those variants. In an immature rat uterotrophic model, ARV-471 degrades rat uterine ER and demonstrates no agonist activity. Daily, oral-administration of single agent ARV-471 (3, 10, and 30 mpk) leads to significant anti-tumor activity of estradiol-dependent MCF7 xenografts and concomitant tumor ER protein reductions of &gt;90% at study termination. Moreover, when a CDK4/6 inhibitor is combined with ARV-471 in the MCF7 model, even more pronounced tumor growth inhibition is observed (131% TGI), accompanied by significant reductions in ER protein levels. In an ESR1 Y537S, hormone-independent patient-derived xenograft model, ARV-471 at 10 mpk completely inhibited growth and also significantly reduced mutant ER protein levels. Taken together, the preclinical data of ARV-471 supports its continued development as a best-in-class oral ER PROTAC® protein degrader. These preclinical data supported the clinical development of ARV-471 for the treatment of patients with breast cancer. The discovery, chemical structure and initial clinical data of ARV-471 will be presented.

Citation Format: Lawrence B. Snyder, John J. Flanagan, Yimin Qian, Sheryl M. Gough, Monica Andreoli, Mark Bookbinder, Gregory Cadelina, John Bradley, Emma Rousseau, Julian Chandler, Ryan Willard, Jennifer Pizzano, Craig M. Crews, Andrew P. Crew, John Houston, Marcia Dougan Moore, Ron Peck, Ian Taylor. The discovery of ARV-471, an orally bioavailable estrogen receptor degrading PROTAC for the treatment of patients with breast cancer [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 44.

Structural characterisation of the Chaetomium thermophilum Chl1 helicase

Chl1 is a member of the XPD family of 5'-3' DNA helicases, which perform a variety of roles in genome maintenance and transmission. They possess a variety of unique structural features, including the presence of a highly variable, partially-ordered insertion in the helicase domain 1. Chl1 has been shown to be required for chromosome segregation in yeast due to its role in the formation of persistent chromosome cohesion during S-phase. Here we present structural and biochemical data to show that Chl1 has the same overall domain organisation as other members of the XPD family, but with some conformational alterations. We also present data suggesting the insert domain in Chl1 regulates its DNA binding.

Development of a Mobile, Self-Sovereign Identity Approach for Facility Birth Registration in Kenya

Birth registration is a critical element of newborn care. Increasing the coverage of birth registration is an essential part of the strategy to improve newborn survival globally, and is central to achieving greater health, social, and economic equity as defined under the United Nations Sustainable Development Goals. Parts of Eastern and Southern Africa have some of the lowest birth registration rates in the world. Mobile technologies have been used successfully with mothers and health workers in Africa to increase coverage of essential newborn care, including birth registration. However, mounting concerns about data ownership and data protection in the digital age are driving the search for scalable, user-centered, privacy protecting identity solutions. There is increasing interest in understanding if a self-sovereign identity (SSI) approach can help lower the barriers to birth registration by empowering families with a smartphone based process while providing high levels of data privacy and security in populations where birth registration rates are low. The process of birth registration and the barriers experienced by stakeholders are highly contextual. There is currently a gap in the literature with regard to modeling birth registration using SSI technology. This paper describes the development of a smartphone-based prototype system that allows interaction between families and health workers to carry out the initial steps of birth registration and linkage of mothers-baby pairs in an urban Kenyan setting using verifiable credentials, decentralized identifiers, and the emerging standards for their implementation in identity systems. The goal of the project was to develop a high fidelity prototype that could be used to obtain end-user feedback related to the feasibility and acceptability of an SSI approach in a particular Kenyan healthcare context. This paper will focus on how this technology was adapted for the specific context and implications for future research.

A Holistic Self-learning Approach for Young Adult Depression and Anxiety Compared to Medication-Based Treatment-As-Usual

A package of biopsychosocial services for young adults experiencing psychological distress was evaluated and compared to usual outpatient psychiatric care. Young adults (18-25) with moderate-to-severe symptoms of depression and/or anxiety (n = 26) were enrolled in a 13-week intervention consisting of nutritional coaching and multi-vitamin supplements, weekly educational and peer support groups, and a modest financial stipend to engage with physical or expressive activities. A comparison group (n = 13) continued with their usual medication-based outpatient care. Program participants reported significantly improved depression, anxiety, severity of distress, overall quality of life, and empowerment over 4 months, with progress maintained or further improved at 2-month follow-up. No evidence of change on any outcome was observed for comparison group participants. Although long-term impacts on mental health trajectories and reliance on psychotropic medications remain unknown, a holistic self-learning approach is a viable alternative to standard outpatient psychiatric care for young adults.

Incidences and Range of Spontaneous Microscopic Lesions in the Eye of Sprague-Dawley Rats and Han Wistar Rats Used in Toxicity Studies

The incidence and range of spontaneous microscopic lesions were determined in the eyes of male and female control Sprague-Dawley and Han Wistar rats. Data were collected retrospectively from 1411, 817, 970, 658, and 3999 rats from control groups of 4-, 13-, 26-, 52-, and 104-week studies, respectively, carried out between 1997 and 2019. Microscopic lesions of the eye were rare in 4- and 13-week studies, uncommon in 26- and 52-week studies, and were of relatively higher incidence in 104-week studies. Neoplastic lesions were sporadic and were only observed in 104-week studies. In Sprague-Dawley rats, the most common lesions (>1% in 104-week studies) were retinal degeneration, retinal rosettes/folds, and lenticular degeneration. The Han Wistar rats presented a range of ocular lesions similar to the Sprague-Dawley rats. However, retinal degeneration occurred with an earlier onset and at higher incidences, ranging from >5% in 26-week studies up to 45.72% in 104-week studies. In both strains, females exhibited higher incidences and severities of retinal degeneration. It is hoped that reference to the incidences reported here will facilitate the differentiation of spontaneous lesions from test article-induced lesions in toxicology studies in these strains of rat.

Abstract 2750: An efficient multiplexing approach to avoid batch effects in single cell RNA- and Ab-seq studies demonstrated in a mouse model of chronic inflammation and obesity

Obesity can weaken the body's immune system and reduce its ability to fight off infections. Current analysis on immune cells from obese mouse models suggests that the immune cells suffer from chronic inflammation. To understand the root cause of this problem, we used single cell sequencing to examine thousands of immune cells isolated from primary and secondary lymphoid organs as well as adipose tissue and compared a diet-induced obesity mouse model with control mice. Cells were stained with 30 BD® AbSeq DNA-barcoded antibodies to enable multiomic analysis, i.e. examining protein alongside mRNA expression in tandem. We also utilized DNA-barcoded universal antibodies from the BD® Single-Cell Multiplexing Kit, which allowed us to combine 8 samples from different mice and tissue types into a single pooled sample, significantly reducing experimental scale and cost while eliminating potential batch effects. The pooled samples were loaded on the BD Rhapsody™ system to perform cell lysis and individual mRNA and cell barcoding, allowing measurement of ~400 immune-related mRNAs and 30 proteins at the single cell level. We were able to efficiently de-multiplex the pooled samples after sequencing. The targeted mRNA and AbSeq panel provided robust clustering of immune cell types and showed that genes related to critical immune responses, including inflammation and lymphocyte activation, are differentially regulated in specific immune-cell subsets in the obese mouse model. Using this multiomic analysis of genes differentially regulated in immune cells from different tissues, we propose a model to explain the immuno-phenotype we observed in obese mouse.

For Research Use Only. Not for use in diagnostic or therapeutic procedures.

BD, the BD Logo, and Rhapsody are trademarks of Becton, Dickinson and Company or its affiliates. © 2019 BD. All rights reserved.

Citation Format: Hye-Won Song, Gisele Baracho, Ian Taylor, Stephanie Widmann, Stefanie Mortimer. An efficient multiplexing approach to avoid batch effects in single cell RNA- and Ab-seq studies demonstrated in a mouse model of chronic inflammation and obesity [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2750.

Abstract 2166: Deep characterization of in vitro chronically stimulated T cells via single-cell multiomic analysis

A key step in the clinical production of CAR T cells is the expansion of engineered T cells. To generate enough cells for viable adoptive cell therapy, cells must be robustly stimulated, which raises the risk of inducing T-cell exhaustion and reducing therapeutic efficacy. As protocols for T-cell expansion are being developed to optimize CAR T-cell yield, function and persistence, fundamental questions about the impact of in vitro manipulation on T-cell identity are important to answer. Namely: 1) what types of cells are generated during chronic stimulation? 2) how many unique cell states can be defined during chronic stimulation? We sought to answer these fundamental questions by performing single-cell multiomic analysis using BD® AbSeq and BD Rhapsody™ Single-Cell Analysis system to simultaneously measure expression of 38 proteins and 399 genes in human T cells expanded in vitro. This approach allowed us to study - with unprecedented depth - how T cells change throughout chronic stimulation. Human PBMCs from three healthy donors were stimulated for 14 days in the presence of CD3/CD28 antibody-coated beads and recombinant human IL-2. This model system resembles culture conditions that may be used for CAR T-cell expansion. Cells were collected at different time points (day 0, 3, 7 and 14) prior to downstream analysis. Comprehensive immunophenotypic and transcriptomic analysis at day 0 enabled a refined characterization of T-cell maturational states (from naïve to TEMRA cells) and the identification of a donor-specific subset of terminally differentiated T cells that would have been otherwise overlooked using canonical cell classification schema. As expected, T-cell activation induced downregulation of naïve-associated markers and upregulation of effector molecules, proliferation regulators, co-inhibitory and co-stimulatory receptors. Our deep kinetic analysis further revealed clusters of proteins and genes identifying unique states of activation defined by markers temporarily expressed upon 3 days of stimulation (PD-1, CD69, LTA), markers constitutively expressed throughout chronic activation (CD25, GITR, LGALS1), and markers uniquely up-regulated upon 14 days of stimulation (CD39, ENTPD1, TNFSF10). Notably, different ratios of cells expressing activation or exhaustion markers were measured at each time point. These data indicate heterogeneity and plasticity of chronically stimulated T cells in response to different kinetics of activation. We demonstrate the power of a single-cell multiomic approach to comprehensively characterize T cells and to precisely monitor changes in differentiation, activation and exhaustion signatures in response to different activation protocols. For Research Use Only. Not for use in diagnostic or therapeutic procedures. BD, the BD Logo, and Rhapsody are trademarks of Becton, Dickinson and Company or its affiliates. © 2019 BD. All rights reserved.

Citation Format: Mirko Corselli, Suraj Saksena, Margaret Nakamoto, Woodrow E. Lomas, Ian Taylor, Pratip K. Chattopadhyay. Deep characterization of in vitro chronically stimulated T cells via single-cell multiomic analysis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2166.

Abstract 1345: Advances in single cell whole transcriptome analysis: Single nucleus RNAseq and simultaneous protein and mRNA profiling using the BD RhapsodyTM Single-Cell Analysis system and BD® AbSeq

Advances in high-throughput single cell whole transcriptome analysis (WTA) have enabled the discovery of biomarkers and cellular pathways critical to resolving diversity in diseases. Despite these advances, challenges still remain in comprehensively profiling single cells. Here we address two challenges, limited use of frozen tissues, and inability to resolve post-transcriptional differences from cell to cell.

Single-cell RNAseq often requires intact single cells to get good resolution of signal, preventing the use of archival frozen samples. To overcome this limitation, we have tested the possibility to use dissociated nuclei that can be isolated from frozen samples in the BD RhapsodyTM Single-Cell Analysis system. As a proof of concept, we compared high throughput single-nucleus WTA data to that produced from single-cell RNAseq from the same cell type. Our data showed that mRNAs from single nuclei can be captured, and amplified using the BD RhapsodyTM system. Furthermore although the number of molecules detected is lower in nucleus, probably due to lower mRNA content, their expression profiles are well correlated with Pearson's correlation coefficient over 0.9. This opens up the possibility to conduct single cell transcriptomic analysis on the large pool of archived frozen specimens, expanding the variety and number of disease samples that can be examined at the single cell level in the BD RhapsodyTM system.

A second limitation of WTA analysis is that it only provides information about gene regulation at the transcript level. Given that regulation critical for cellular pathways is often found not only at the transcriptional level but also at the post-transcriptional level, quantitative analysis of proteins and mRNAs at the single cell level can provide deeper understanding of the disease cells. Here, we used DNA-barcoded antibodies BD® AbSeq to enable multiomic analysis, examining protein alongside mRNA expression and enabling simultaneous transcriptional and post-transcriptional gene profiling in single cells. Our data show that upon activation human peripheral blood mononuclear cells and isolated T cells undergo regulation of markers at the protein level that cannot be resolved at the mRNA level. Several key markers used to define activation states including CD69 and L-Selectin were found to be regulated at the protein level confirming that addition of protein analysis to WTA can generate more comprehensive cell profiling.

These approaches offer flexibility and choice in experimental design and allow users to utilize archived frozen samples or to obtain mRNA and protein profiles from single cells.

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Citation Format: Hye-Won Song, Gretchen Y. Lam, Margaret Nakamoto, Punya Narayan, Ian Taylor, Stefanie Mortimer. Advances in single cell whole transcriptome analysis: Single nucleus RNAseq and simultaneous protein and mRNA profiling using the BD RhapsodyTM Single-Cell Analysis system and BD® AbSeq [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1345.

Comparison of longevity and common tumor profiles between Sprague-Dawley and Han Wistar rats

The Sprague Dawley (SD) and Han Wistar (HW) are the two most commonly used rat strains in Europe and the US, with the Han Wistar increasing in popularity because of its greater longevity and lower tumor burden. This survey was undertaken at Covance CRS (Huntingdon and Eye) to compare in-house longevity and common spontaneous tumor profiles of the two strains with published data. Data were compiled from 104-week studies started between 2010 and 2017. Mean survival was greater for both sexes of HWs when compared with SDs. Pituitary tumors were the commonest in both strains, with slightly higher incidences and more malignant tumors in SDs of both sexes. Mammary tumors were the second most common tumor in both strains; the incidence being greater in SDs compared to HWs. Benign pheochromocytomas of the adrenal and fibromas of the skin/subcutis were commoner in male SDs than in HWs. Granular cell tumors of the uterine tract were recorded only in SDs, but uterine stromal and glandular tumors were more common in HWs, which also displayed a higher incidence of granulosa cell tumors of the ovaries. Vascular tumors of the mesenteric lymph nodes, thymomas and follicular cell tumors of the thyroids were recorded at a higher incidence in HWs than in SDs. Tumor profiles of other common tumors were broadly similar between the two strains. The results of this survey correlate closely with similar comparisons made at other laboratories, and with data compiled at our laboratories 10 years ago and published as a poster.

First-in-human phase I study of ARV-110, an androgen receptor (AR) PROTAC degrader in patients (pts) with metastatic castrate-resistant prostate cancer (mCRPC) following enzalutamide (ENZ) and/or abiraterone (ABI)

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Background: Proteolysis Targeting Chimera (PROTAC) protein degraders induce selective degradation of targeted proteins by engaging the ubiquitin proteasome system. ARV-110 is an orally bioavailable PROTAC that specifically degrades AR ≥ 95% and achieves anti-tumor activity in ENZ-naïve and -resistant prostate cancer xenograft models. Methods: To define the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of ARV-110, pts with ≥ 2 prior therapies for mCRPC, including ENZ and/or ABI, received ARV-110 orally once daily. Dose escalation is per 3+3 design. Endpoints include dose limiting toxicities (DLTs), adverse events (AEs), pharmacokinetics (PK), biomarkers (e.g., AR mutation analysis), RECIST and PSA response. Results: By January 2020, 18 pts were dosed: 35 mg (N = 3), 70 mg (N = 4), 140 mg (N = 8), 280 mg (N = 3). 12 pts received both ENZ and ABI; 14 received prior chemotherapy. 1 of 18 pts experienced a DLT (280 mg) of Grade (Gr) 4 elevated AST/ALT followed by acute renal failure while taking rosuvastatin (ROS). A 2nd pt had Gr 3 AST/ALT with ROS that resolved off ROS, permitting ARV-110 retreatment. ROS plasma concentrations demonstrated significant increases concurrent with AST/ALT elevations in both pts. Subsequently, ROS was prohibited without further ≥Gr 2 AST/ALT AEs. No other related Gr 3/4 AEs were reported. ARV-110 PK was generally dose proportional and at 140 mg reached levels associated with preclinical anti-tumor activity. 15 pts were evaluable for PSA response (excludes 1 pt stopped after 1 dose for early progression and 2 pts initiated 2 weeks before cutoff, all at 140 mg). Of these, 8 pts initiated dosing at ≥140 mg. 2 pts achieved confirmed PSA declines of >50%, both at 140 mg. Prior therapy in both pts included ENZ and ABI, chemotherapy, bicalutamide and radium-223 plus other regimens. 1 pt had 2 AR mutations known to confer ENZ resistance. The 2nd pt also achieved an unconfirmed RECIST partial response (confirmatory scan pending). Both responses were ongoing at data cutoff (8+ and 21+ weeks of treatment). Conclusions: To date, ARV-110 has an acceptable safety profile. Concurrent ROS is now prohibited. MTD has not yet been established; determination of RP2D continues. ARV-110 demonstrates antitumor activity in mCRPC after ENZ/ABI with 2 ongoing confirmed PSA responses, one of which was associated with tumor reduction. Updated data for this first PROTAC in clinical testing will be presented. Clinical trial information: NCT03888612 .

Deep characterization of in vitro chronically stimulated T cells via single-cell multiomic analysis

To generate enough cells for viable adoptive cell therapy, cells must be robustly stimulated, which raises the risk of inducing T-cell exhaustion and reducing therapeutic efficacy. To comprehensively characterize in vitro chronically expanded human T cells, we performed single-cell multiomic analysis using BD® AbSeq and BD Rhapsody™ Single-Cell Analysis system for simultaneous measurement of the expression of 38 proteins and 399 genes. Comprehensive immunophenotypic and transcriptomic analysis at day 0 enabled a refined characterization of T-cell maturational states. T-cell activation induced by anti-CD3/CD28 beads and recombinant human IL-2 led to downregulation of naïve-associated markers and upregulation of effector molecules, proliferation regulators, co-inhibitory and co-stimulatory receptors. Our deep kinetic analysis further revealed clusters of proteins and genes identifying unique states of activation defined by markers temporarily expressed upon 3 days of stimulation, markers constitutively expressed throughout chronic activation, and markers uniquely up-regulated upon 14 days of stimulation. These data indicate heterogeneity and plasticity of chronically stimulated T cells in response to different kinetics of activation. We demonstrate the power of a single-cell multiomic approach to comprehensively characterize T cells and to precisely monitor changes in differentiation, activation and exhaustion signatures in response to different activation protocols.

For Research Use Only. Not for use in diagnostic or therapeutic procedures.

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Molecular cytometry identifies a wide range of translationally relevant markers in tumor and peripheral immune cells of lung cancer patients

Many immunotherapy drugs, used singly or in combination, are emerging. To realize precision oncology, and better design clinical trials, in-depth immune profiling is key. Many new technologies are available; the most promising simultaneously analyzes &gt;102 proteins and 400 mRNA cell-by-cell (molecular cytometry). Using this technology, we deeply profiled TIL, from freshly resected lung tissue, and PBMC collected at surgery (n=10).

Antibody staining was robust, with all canonical cell populations at expected frequency. We identified markers uniquely upregulated in TIL, including CXCR6, CD39, CD26, CD69, CD103, and RGS. We also asked what markers were uniquely enriched in PD1-TIL, in order to find other drug targets for patients who fail Nivolumab. We found many molecules upregulated in PD1-TIL, including CD326, CD98, LGALS3, TIM3, CD54, CD235ab, CXCL8, CD141, and CD117. We further identified precise combinations of these markers that inform design of combination immunotherapy.

We also characterized immune landscapes in metastatic disease vs. localized adenocarcinoma, finding drug targets and tumor-immune interactions are different across these settings. For example, T-cell activation markers are downregulated in metastatic tissue, e.g., HLADR (p = 1.5E-16), CD69 (p=2.9e-10), and CD38 (p=3.2e-16). CD103 was also highly downregulated (p=1.9E-14). Notably, in metastatic disease various myeloid proteins are elevated, including CD206 (p=0.002), CD32 (p=0.02), and CD61 (p=0.006). We also characterized the degree of immune exhaustion, using ratios of ZBED2:LGALS in cells. In summary, we demonstrate the utility of molecular cytometry for providing unique (and translationally-relevant) insight into lung cancer.

Assessing CD8+ cytotoxic T-cell dysfunction in obesity and its implications in anti-PD-1 blockade therapy

In chronic conditions, notably cancers, CD8+ cytotoxic T cells gradually lose their effector functions due to constant exposure to antigens and consequent upregulation of inhibitory receptors like PD-1. In this regard, PD-1 blockade therapy was shown to bolster cytotoxic T-cell response and improve disease prognosis in some cases. PD-1 mediated T cell dysfunction is also involved in obesity-induced tumorigenesis. In this study, we used a molecular cytometry approach to better understand the disturbances caused by obesity in immune cells. A detailed single-cell analysis of various cell compartments revealed a unique population of CD8+ cytotoxic T cells in the epididymal fat of mice consuming a high fat diet for 16 weeks. These cells showed high expression of proteins and/or mRNA transcripts for various inhibitory receptors, including PD-1. Based on these results, we created a 28-color panel for high-throughput cell analysis at multiple time points over the 16-week period, using a BD FACSymphony™. The frequency of CD8+PD-1+ T cells in the fat correlated with the numbers of inflammatory cells, suggesting that the dysfunctional phenotype resulted from a growth in inflammation over time. The functional state of the CD8+PD-1+ cells was also examined by challenging these cells with or without PD-1 blockade. Taken together the data delineated a refined application for a broad analysis of immune cells in the fat and provided insights into the effects of obesity-induced T-cell dysfunction in mice.

For Research Use Only. Not for use in diagnostic or therapeutic procedures.

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Abstract B90: Deep characterization of in vitro chronically stimulated T cells through single-cell multiomic analysis

A key step in the clinical production of CAR T cells is the expansion of engineered T cells. To generate enough cells for a therapeutic product, cells must be robustly stimulated, which raises the risk of inducing T-cell exhaustion and reducing therapeutic efficacy. As protocols for T-cell expansion are being developed to optimize CAR T cell yield, function, and persistence, fundamental questions about the impact of in vitro manipulation on T-cell identity are important to answer. Namely: 1) What types of cells are generated during chronic stimulation? 2) How many unique cell states can be defined during chronic stimulation? We sought to answer these fundamental questions by performing single-cell multiomic analysis to simultaneously measure expression of 38 proteins and 399 genes in human T cells expanded in vitro. This approach allowed us to study—with unprecedented depth—how T cells change over the course of chronic stimulation. Human PBMCs from three healthy donors were continuously stimulated for 14 days in the presence of CD3/CD28 antibody-coated beads and recombinant human IL-2. This model system was developed to resemble culture conditions that may be used for CAR T cell expansion. Cells were collected at different time points (day 0, 3, 7, and 14) prior to downstream analysis. Comprehensive immunophenotypic and transcriptomic analysis at day 0 enabled a refined characterization of T-cell maturational states (from naive to TEMRA cells) and the identification of a donor-specific subset of terminally differentiated T-cells that would have been otherwise overlooked using canonical cell classification schema. As expected, T-cell activation induced downregulation of naive-associated markers and upregulation of effector molecules, proliferation regulators, coinhibitory and costimulatory receptors. Our deep kinetic analysis further revealed clusters of proteins and genes identifying unique states of activation defined by markers temporarily expressed upon 3 days of stimulation (PD-1, CD69, LTA), markers constitutively expressed throughout chronic activation (CD25, GITR, LGALS1), and markers uniquely upregulated upon 14 days of stimulation (CD39, ENTPD1, TNFSF10). Notably, different ratios of cells expressing activation or exhaustion markers were measured at each time point. These data indicate high heterogeneity and plasticity of chronically stimulated T cells in response to different kinetics of activation. In this study, we demonstrate the power of a single-cell multiomic approach to comprehensively characterize T cells and to precisely monitor changes in differentiation, activation, and exhaustion signatures in response to different activation protocols.

Citation Format: Mirko Corselli, Margaret Nakamoto, Chip Lomas, Ian Taylor, Suraj Saksena, Tariq Arshad, Pratip K. Chattopadhyay. Deep characterization of in vitro chronically stimulated T cells through single-cell multiomic analysis [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B90.

Changes in the elimination and resurgence of alcohol-maintained behavior in rats and the effects of naltrexone

Resurgence may be a mechanism of relapse in alcohol use disorder patients upon discharge from treatment as part of an abuse-treatment-relapse cycle. Adjunctive pharmacotherapies may be a means to facilitate behavioral treatments and block resurgence. Experiments were conducted using a model of alcohol self-administration to assess the repeatability of the elimination and resurgence of alcohol-maintained behavior and the effects of naltrexone. Experiments had three phases. In Phase 1, behavior was maintained by oral alcohol under a fixed-ratio schedule. In Phase 2, behavior was extinguished via condensed milk delivery under a differential-reinforcement-of-other-behavior (DRO) schedule. In Phase 3, the DRO schedule was eliminated. In Experiment 1, this 3-phase cycle was replicated 4 times. Across replications, response rates and dose of alcohol consumed did not differ in Phase 1, alcohol-maintained behavior was eliminated more rapidly in Phase 2, and the resurgence effect was generally stable in Phase 3. In Experiment 2, naltrexone was administered in Phase 2, Phase 3, or both Phases 2 and 3, to separate groups of rats. Naltrexone facilitated the elimination of alcohol-maintained behavior in Phase 2 and, the resurgence of alcohol-maintained behavior was reduced only for those rats that received naltrexone in both phases. Together, these experiments demonstrate that the resurgence of alcohol-maintained behavior is replicable within-subjects and, further, resurgence of alcohol-maintained behavior may be a useful model to evaluate pharmacological interventions to facilitate behavioral treatments and reduce the likelihood of relapse. Results with naltrexone support the use of medication-assisted therapy approaches to reduce relapse risk in patients. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Robotic pick-and-place of novel objects in clutter with multi-affordance grasping and cross-domain image matching

This article presents a robotic pick-and-place system that is capable of grasping and recognizing both known and novel objects in cluttered environments. The key new feature of the system is that it handles a wide range of object categories without needing any task-specific training data for novel objects. To achieve this, it first uses an object-agnostic grasping framework to map from visual observations to actions: inferring dense pixel-wise probability maps of the affordances for four different grasping primitive actions. It then executes the action with the highest affordance and recognizes picked objects with a cross-domain image classification framework that matches observed images to product images. Since product images are readily available for a wide range of objects (e.g., from the web), the system works out-of-the-box for novel objects without requiring any additional data collection or re-training. Exhaustive experimental results demonstrate that our multi-affordance grasping achieves high success rates for a wide variety of objects in clutter, and our recognition algorithm achieves high accuracy for both known and novel grasped objects. The approach was part of the MIT–Princeton Team system that took first place in the stowing task at the 2017 Amazon Robotics Challenge. All code, datasets, and pre-trained models are available online at http://arc.cs.princeton.edu/

Single cell whole transcriptome analysis of disease cells to generate a targeted RNA-sequencing gene panel for the simultaneous analysis of targeted mRNA and protein

Single cell RNA-sequencing (scRNA-seq) is a powerful tool for understanding the sample heterogeneity of individual cells. Many methods rely on whole transcriptome analysis (WTA) to get a snapshot of the entire cellular landscape. Although WTA analysis can be used to discover novel biomarkers, this technique can be expensive. To enable scaling of experiments, WTA data can be mined to design targeted gene panels. To showcase this, we used single cell sequencing to examine thousands of B cells isolated from the bone marrow and peripheral blood of chronic lymphocytic leukemia (CLL) and healthy donors. B cells that had been sorted using the BD FACSMelody™ cell sorter were multiplexed using the BD™ Human Single-Cell Multiplexing Kit and pooled before being processed on the BD Rhapsody™ system, thereby minimizing batch effects. The resulting data was mined to design a panel of differentially expressed genes between CLL and healthy B cells that could be used for subsequent CLL phenotyping. By combining this panel with the BD Rhapsody™ Immune Response Panel (together comprising ~500 mRNAs), along with 36 DNA-barcoded BD™ AbSeq antibodies, we were able to simultaneously analyze mRNA and protein targets from a new subset of CLL and healthy B cells for additional high-resolution analysis. This study showcases the power of using WTA data to design specific gene panels that can be used alone or in combination with existing targeted panels for routine and cost-effective transcriptional profiling at a single cell level.

For Research Use Only. Not for use in diagnostic or therapeutic procedures.

BD, the BD Logo, FACSMelody, and Rhapsody are trademarks of Becton, Dickinson and Company. © 2019 BD and its subsidiaries. All rights reserved.

Simultaneous analysis of mRNA and proteins in immune cells using the BD&[trade] Single-Cell Multiplexing Kit and BD&[trade] AbSeq reagents on the BD Rhapsody&[trade] system for high-resolution interrogation of differential immune regulation

Obesity can weaken the body’s immune system and trigger chronic inflammation. To understand the root cause of this problem, we used single cell sequencing to examine thousands of immune cells isolated from primary and secondary lymphoid organs as well as adipose tissue and compared a diet-induced obesity mouse model with control mice. Cells were stained with 30 DNA-barcoded antibodies from BD™ AbSeq reagents to enable multiomic analysis, i.e. examining protein alongside mRNA expression in tandem. We also utilized DNA-barcoded universal antibodies from the BD™ Single-Cell Multiplexing Kit, which allowed us to combine 8 samples from different mice and tissue types into a single pooled sample, significantly reducing experimental scale and cost while eliminating potential batch effects. The pooled samples were loaded on the BD Rhapsody™ system to perform cell lysis and individual mRNA and cell barcoding, allowing measurement of ~400 immune-related mRNAs and 30 proteins at the single cell level. We were able to de-multiplex the pooled samples with high specificity after sequencing. The targeted mRNA and AbSeq panel provided robust clustering of immune cell types and showed that genes related to critical immune responses, including inflammation and lymphocyte activation, are differentially regulated in specific immune-cell subsets in obese mouse. Using this multiomic analysis of genes differentially regulated in immune cells from different tissues, we propose a model to explain the immuno-phenotype we observed in obese mouse.

For Research Use Only. Not for use in diagnostic or therapeutic procedures.

BD, the BD Logo, and Rhapsody are trademarks of Becton, Dickinson and Company. © 2019 BD and its subsidiaries. All rights reserved.

Single cell multiomic analysis of chronically stimulated T cells displaying hallmarks of T-cell exhaustion

T-cell exhaustion is a dysfunctional state caused by persistent antigen stimulation mediated by chronic infections or cancer. Current immunotherapy approaches focus on reinvigorating exhausted T cells through immune-receptor-blocking antibodies. A deeper understanding of the exhausted T-cell state is crucial for identification of new therapeutic targets. Single cell RNA-sequencing (scRNA-seq) is a powerful tool for resolving heterogeneity in complex systems like these; however the lack of protein information for the same cells can make it difficult to identify cells of interest or detect cellular responses. To resolve both mRNA and protein information in the same assay, we utilized DNA-conjugated BD™ AbSeq antibodies to profile protein and mRNA expression, using high-throughput sequencing analysis at the single cell level. Sorted T cells that had been transiently and chronically stimulated were multiplexed using the BD™ Single-Cell Multiplexing Kit and pooled before undergoing cell partitioning and cDNA capture on the BD Rhapsody™ system; this minimized batch effects and saved time and reagents. A panel of 400 mRNA targets alongside the 39-plex antibody panel was used for the study. We showed that cell-type resolution increased with higher protein plex, and the addition of mRNA information alongside protein markers revealed candidate protein markers for specific cell states. This study showcased the power of multiomics in analyzing heterogenous cell populations and cell states and answering complex biological questions.

Research Use Only. Not for use in diagnostic or therapeutic procedures.

BD, the BD Logo, and Rhapsody are trademarks of Becton, Dickinson and Company. © 2019 BD and its subsidiaries. All rights reserved.

ARV-110: An oral androgen receptor PROTAC degrader for prostate cancer

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Background: The Androgen Receptor (AR) remains the principal driver of castration-resistant prostate cancer during the transition from a localized to metastatic disease. Most patients initially respond to inhibitors of the AR pathway, but the response is often relatively short-lived. The majority of patients progressing on enzalutamide or abiraterone exhibit genetic alterations in the AR locus, either in the form of amplifications or point mutations in the AR gene. Given these mechanisms of resistance, our goal is to eliminate the AR protein using the PROteolysis TArgeting Chimera (PROTAC) technology. Methods: Here we report an orally bioavailable small molecule AR PROTAC degrader, ARV-110, that promotes ubiquitination and degradation of AR. This molecule has been characterized in in vitro degradation and functional assays, and DMPK, toxicology and preclinical efficacy studies. Results: ARV-110 robustly degrades AR in all cell lines tested, with an observed half-maximal degradation concentration (DC50) of ~1 nM. ARV-110 treatment leads to highly selective AR degradation, as demonstrated by proteomic studies. In VCaP cells, PROTAC-mediated AR degradation suppresses the expression of the AR-target gene PSA, inhibits AR-dependent cell proliferation, and induces apoptosis at low nanomolar concentrations. Further, ARV-110 degrades clinically relevant mutant AR proteins and retains activity in a high androgen environment. In mouse xenograft studies, greater than 90% AR degradation is observed at a 1 mg/kg PO QD dose. Significant inhibition of tumor growth and AR signaling has been achieved in LNCaP, VCaP and prostate cancer patient derived xenograft (PDX) models. Notably, ARV-110 demonstrates in vivo efficacy and reduction of AR-target gene expression in a long term, castrate, enzalutamide-resistant VCaP tumor model. Conclusions: In summary, we report preclinical data on an orally bioavailable AR PROTAC degrader, ARV-110, that demonstrates efficacy in multiple prostate cancer models. ARV-110 has completed IND-enabling studies and FIH studies are planned for 1Q2019.

Reducing workplace accidents through the use of leadership interventions: A quasi-experimental field study

There is increasing evidence to suggest that leaders need to use a combination of leader behaviors to successfully improve safety, including both transformational and transactional styles, but there has been limited testing of this idea. We developed a leadership intervention, based on supervisor training in both transformational and active transactional behaviors, and implemented it with supervisors at a UK-based chemical processing company. The study found that the supervisory training intervention led to significant improvements in perceived employee safety climate, over an eight-week period, relative to the comparison group. Although we found no change in the frequency of leader behaviors, the intervention was effective in helping supervisors to apply active transactional leader behaviors in a safety-critical context. The results indicated that transformational leader behaviors were already at a high level and effectively linked to safety. Our findings suggest not only that employees may be receptive to safety-related active transactional behaviors within high-risk situations, but furthermore, leaders can be trained to adjust their behaviors to focus more on active transactional behaviors in safety-critical contexts.

Abstract 5236: ARV-110: An androgen receptor PROTAC degrader for prostate cancer

The Androgen Receptor (AR) remains the principal driver of castration-resistant prostate cancer during the transition from a localized to metastatic disease. Most patients initially respond to inhibitors of the AR pathway, but the response is often short-lived. The majority of patients progressing on enzalutamide or abiraterone exhibit genetic alterations in the AR locus, either in the form of amplifications or point mutations in the AR gene. Given these mechanisms of resistance, our goal is to eliminate the AR protein using the PROteolysis TArgeting Chimera (PROTAC) technology. Here we report an orally bioavailable small molecule ARV-110 that leads to ubiquitination and degradation of AR. ARV-110 completely degrades AR in all cell lines tested, with an observed 50% degradation concentration (DC50) &lt; 1 nM. PROTAC-mediated AR degradation suppresses the expression of the AR-target genes PSA and FKBP5, inhibits AR-dependent cell proliferation, and induces potent apoptosis in VCaP cells. ARV-110 degrades clinically relevant mutant AR proteins and retains activity in a high androgen environment. In mouse xenograft studies, greater than 90% AR degradation is observed at a 1 mg/kg PO QD dose. Significant inhibition of tumor growth and AR signaling can be achieved in both an intact and castrate setting. Further, ARV-110 demonstrates in vivo efficacy and reduction of oncogenic Erg protein in a long term, castrate, enzalutamide-resistant VCaP tumor model. DMPK and exploratory toxicology studies show robust oral, dose proportional drug exposure in rodent and non-rodent species. In summary, we report preclinical data on ARV-110, an orally bioavailable androgen receptor PROTAC degrader that demonstrates efficacy in enzalutamide-resistant prostate cancer.

Citation Format: Taavi Neklesa, Lawrence B. Snyder, Ryan R. Willard, Nicholas Vitale, Kanak Raina, Jennifer Pizzano, Deborah Gordon, Mark Bookbinder, Jennifer Macaluso, Hanqing Dong, Zheng Liu, Caterina Ferraro, Gan Wang, Jing Wang, Craig M. Crews, John Houston, Andrew P. Crew, Ian Taylor. ARV-110: An androgen receptor PROTAC degrader for prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5236.

X-ray and Ultrasound Localization of Non-Palpable Breast Lesions and Difficulties in Management

Seventy-four patients who have had biopsy of a non-palpable breast lesion are reviewed. A double-dye localization technique was used in 88% while in 12% localization of the lesion was best achieved by ultrasound mammography. Biopsy was successful in 70 patients (95%) at the first attempt. The overall incidence of malignancy was 20%, being greater in asymptomatic patients (32%) than in patients with mastalagia (16%). Re-excision of the biopsy site in these patients showed residual cancer in 33%. It is suggested that both careful examination of the operative specimen and postoperative mammography may be necessary to ensure that the original lesion has been removed. Re-excision of the biopsy site appears to be necessary when the histology is malignant.

After Surgery for Breast Cancer: Which Mode of Surveillance?

Five hundred and ten women attending a specialized breast clinic for follow-up after surgery of early breast cancer (Stage I and II) have been studied. Recurrence was found most often (58%) in symptomatic women who returned to the clinic earlier than planned. Only 3% of asymptomatic patients had recurrent disease. It is concluded that counselling in symptoms of recurrent breast cancer would allow more efficient follow-up.

Management of Acute Lower Gastrointestinal Haemorrhage in a Surgical Unit Over a 4-Year Period

Over a 4-year period 107 patients, 5% of all emergency admissions, were admitted to one surgical unit with significant lower gastrointestinal haemorrhage (requiring more than a 2-unit transfusion of blood). Twenty-three individuals required more than 3 units of blood, and 7 life-saving surgery. All subjects undergoing surgery required more than 3 units of blood in the first 24 hours of admission. Arteriography was diagnostic in 5 of the 9 subjects in whom it was performed. Arteriography was positive if performed in the first 24 hours of admission. A flow chart of the management of patients with lower gastrointestinal haemorrhage is presented.

Assessing physiotherapists' communication skills for promoting patient autonomy for self-management: reliability and validity of the communication evaluation in rehabilitation tool

PURPOSE

To assess the inter-rater reliability and concurrent validity of the Communication Evaluation in Rehabilitation Tool, which aims to externally assess physiotherapists competency in using Self-Determination Theory-based communication strategies in practice.

MATERIALS AND METHODS

Audio recordings of initial consultations between 24 physiotherapists and 24 patients with chronic low back pain in four hospitals in Ireland were obtained as part of a larger randomised controlled trial. Three raters, all of whom had Ph.Ds in psychology and expertise in motivation and physical activity, independently listened to the 24 audio recordings and completed the 18-item Communication Evaluation in Rehabilitation Tool. Inter-rater reliability between all three raters was assessed using intraclass correlation coefficients. Concurrent validity was assessed using Pearson's r correlations with a reference standard, the Health Care Climate Questionnaire.

RESULTS

The total score for the Communication Evaluation in Rehabilitation Tool is an average of all 18 items. Total scores demonstrated good inter-rater reliability (Intraclass Correlation Coefficient (ICC) = 0.8) and concurrent validity with the Health Care Climate Questionnaire total score (range: r = 0.7-0.88). Item-level scores of the Communication Evaluation in Rehabilitation Tool identified five items that need improvement.

CONCLUSION

Results provide preliminary evidence to support future use and testing of the Communication Evaluation in Rehabilitation Tool. Implications for Rehabilitation Promoting patient autonomy is a learned skill and while interventions exist to train clinicians in these skills there are no tools to assess how well clinicians use these skills when interacting with a patient. The lack of robust assessment has severe implications regarding both the fidelity of clinician training packages and resulting outcomes for promoting patient autonomy. This study has developed a novel measurement tool Communication Evaluation in Rehabilitation Tool and a comprehensive user manual to assess how well health care providers use autonomy-supportive communication strategies in real world-clinical settings. This tool has demonstrated good inter-rater reliability and concurrent validity in its initial testing phase. The Communication Evaluation in Rehabilitation Tool can be used in future studies to assess autonomy-supportive communication and undergo further measurement property testing as per our recommendations.

Use of Ultrasound Localization to Improve Results of Fine Needle Aspiration Cytology of Breast Masses

A prospective randomized controlled trial of 116 patients with breast masses was conducted to compare the accuracy of ‘blind’ aspiration cytology performed in the clinic with aspiration cytology using ultrasound localization. The unsatisfactory aspiration cytology rate was significantly reduced by ultrasound localization (P=0.028). This was mainly due to an improvement in the unsatisfactory rate for tumours less than 3 cm in diameter (P=0.036). The results were influenced by the number of needle manoeuvres performed, < 10 needle manoeuvres being associated with a 54% unsatisfactory aspiration rate compared with 25% when > 10 manoeuvres were performed (P= <0.02). One experienced aspirator in the clinic had results comparable to those achieved with ultrasound localization.

It is concluded that experience and technique are the most important factors in obtaining a satisfactory aspirate from breast masses. Routine ultrasound localization prior to aspiration confers some benefit. Consideration should be given to the use of the ultrasound-assisted technique following a previous unsatisfactory aspiration, particularly if the tumour is less than 3 cm in diameter.

Mortality in a University Surgical Unit: What is an Avoidable Death?

Between January 1978 and December 1987 there were 23 557 surgical admissions to the University Surgical Unit in Southampton. During this period there were 543 deaths, an overall death per admission rate of 2.3%. During the 10-year period the number of admissions per year had risen from 1884 in 1978 (death per admission=3.6%) to 3467 in 1987 (death per admission rate=1.7%).

At the monthly audit meeting an attempt was made to classify each death as ‘avoidable’ or ‘unavoidable’. During this 10-year period it was considered that there were 89 ‘avoidable’ deaths. This represents an avoidable mortality rate (AMR) of 0.38%.

These ‘avoidable’ deaths were due to a wide variety of causes and this paper discusses the lessons learnt from a review of surgical mortality and outlines how units might compare results.

Non-Specific Abdominal Pain-an Expensive Mystery

Non-specific abdominal pain (NSAP) is a common cause of urgent admission to surgical wards. We studied 80 such patients prospectively. NSAP was commonest in female patients under 30. The pain was localized in the right lower quadrant in 32 patients (40%) and in 56 (70%) the pain was aggravated by movement. Viral studies failed to show any abnormality except in one patient with raised acute and convalescent titres but three patients had raised antistreptolysin 0 titres. The psychological results demonstrated that the NSAP group had the same levels of anxiety and depression as the control group and also had no evidence of increased preceding life events.

Evaluation of a ‘DIY’ Test for the Detection of Colorectal Cancer

A new type of faecal occult blood test, EZ-Detect™, has been evaluated in 404 patients presenting with symptoms suggestive of colorectal disease. The test avoids handling of stools and gives a result which patients can read themselves - factors which may increase patient compliance. In comparison with the Haemoccult™ test, EZ-Detect has the same sensiti-vity for blood in laboratory conditions. In clinical use 98% of patients expressed a preference for EZ-Detect but it detected significantly fewer patients with cancer than did Haemoccult (P = < 0.05). In its present form, this type of test would be unsuitable for population screening for colorectal cancer even if improved compliance is achieved.

Major Abdominal Surgery in the Over-Eighties

We report a prospective controlled trial looking at the outcome of major abdominal surgery judged on the ability of patients to return to their preoperative activity level. Eighty patients were included in the study. Forty of these were over 80 years old and the remainder in the age group 40–65 years. Fifty-four per cent of the over 80s demonstrated an increased level of dependance six months after surgery compared to 18% of the 40–65 year olds. The mortality rate at six months was 42% for the over 80 group. The poor prognosis of elderly surgical patients not only in their increased mortality rate but also in their dependency should be considered before they are subjected to major abdominal surgery.