Organ Donation Research Articles

Heterogeneity of synaptic NMDA receptor responses within individual lamina I pain-processing neurons across sex in rats and humans.

Excitatory glutamatergic NMDA receptors (NMDARs) are key regulators of spinal pain processing, and yet the biophysical properties of NMDARs in dorsal horn nociceptive neurons remain poorly understood. Despite the clinical implications, it is unknown whether the molecular and functional properties of synaptic NMDAR responses are conserved between males and females or translate from rodents to humans. To address these translational gaps, we systematically compared individual and averaged excitatory synaptic responses from lamina I pain-processing neurons of adult Sprague-Dawley rats and human organ donors, including both sexes. By combining patch-clamp recordings of outward miniature excitatory postsynaptic currents with non-biased data analyses, we uncovered a wide range of decay constants of excitatory synaptic events within individual lamina I neurons. Decay constants of synaptic responses were distributed in a continuum from 1-20ms to greater than 1000ms, suggesting that individual lamina I neurons contain AMPA receptor (AMPAR)-only as well as GluN2A-, GluN2B- and GluN2D-NMDAR-dominated synaptic events. This intraneuronal heterogeneity in AMPAR- and NMDAR-mediated decay kinetics was observed across sex and species. However, we discovered an increased relative contribution of GluN2A-dominated NMDAR responses at human lamina I synapses compared with rodent synapses, suggesting a species difference relevant to NMDAR subunit-targeting therapeutic approaches. The conserved heterogeneity in decay rates of excitatory synaptic events within individual lamina I pain-processing neurons may enable synapse-specific forms of plasticity and sensory integration within dorsal horn nociceptive networks. KEY POINTS: Synaptic NMDA receptors (NMDARs) in spinal dorsal horn nociceptive neurons are key regulators of pain processing, but it is unknown whether their functional properties are conserved between males and females or translate from rodents to humans. In this study, we compared individual excitatory synaptic responses from lamina I pain-processing neurons of male and female adult Sprague-Dawley rats and human organ donors. Individual lamina I neurons from male and female rats and humans contain AMPA receptor-only as well as GluN2A, GluN2B- and GluN2D-NMDAR-dominated synaptic events. This may enable synapse-specific forms of plasticity and sensory integration within dorsal horn nociceptive networks. Human lamina I synapses have an increased relative contribution of GluN2A-dominated NMDAR responses compared with rodent synapses. These results uncover a species difference relevant to NMDAR subunit-targeting therapeutic approaches.

Bridging the Gap: Advances and Challenges in Heart Regeneration from In Vitro to In Vivo Applications.

Cardiovascular diseases, particularly ischemic heart disease, area leading cause of morbidity and mortality worldwide. Myocardial infarction (MI) results in extensive cardiomyocyte loss, inflammation, extracellular matrix (ECM) degradation, fibrosis, and ultimately, adverse ventricular remodeling associated with impaired heart function. While heart transplantation is the only definitive treatment for end-stage heart failure, donor organ scarcity necessitates the development of alternative therapies. In such cases, methods to promote endogenous tissue regeneration by stimulating growth factor secretion and vascular formation alone are insufficient. Techniques for the creation and transplantation of viable tissues are therefore highly sought after. Approaches to cardiac regeneration range from stem cell injections to epicardial patches and interposition grafts. While numerous preclinical trials have demonstrated the positive effects of tissue transplantation on vasculogenesis and functional recovery, long-term graft survival in large animal models is rare. Adequate vascularization is essential for the survival of transplanted tissues, yet pre-formed microvasculature often fails to achieve sufficient engraftment. Recent studies report success in enhancing cell survival rates in vitro via tissue perfusion. However, the transition of these techniques to in vivo models remains challenging, especially in large animals. This review aims to highlight the evolution of cardiac patch and stem cell therapies for the treatment of cardiovascular disease, identify discrepancies between in vitro and in vivo studies, and discuss critical factors for establishing effective myocardial tissue regeneration in vivo.

Abstract B107: Community scientist research advocacy program: Training our research community

Abstract Community Scientist Research Advocacy (CSRA) training programs serve as fundamental bridges between communities and researchers. By engaging community members, these programs leverage networks, knowledge, and community perspectives to enhance research endeavors. This approach facilitates trust-building between disadvantaged populations and cancer researchers, particularly in the context of clinical trials participation and tissue donation. The purpose of our program was to develop and evaluate an innovative, bi-coastal, and bilingual program to inform, educate and encourage community members to become cancer research advocates in Florida (FL) and California (CA). Our program was culturally tailored for Black/African American and Hispanic/Latino/a adults. Primary objectives were to increase manpower for cancer research advocacy and increase multi-directional communication between cancer advocates with cancer patients, survivors, caregivers, community members, academic scientists, and policy makers. The CSRA program is a 13-week hybrid program implemented by the CaRE2 Health Equity Center, a bi-coastal partnership between the Florida A&M University, University of Florida, and University of Southern California in Los Angeles. Participants studied into cancers disproportionately affecting Black/African American and Hispanic/Latino/a groups, completing pre- and post-surveys to measure knowledge, self-efficacy, and program satisfaction. Additionally, participants concluded mentored advocacy projects for community implementation, with follow-up implemented at three months post-program completion. To date, a total of 45 adults have graduated from our CSRA program. We present data from the 2023 CSRA cohort (pre, N=21, post, N=19) that included participants from FL and CA, which are among the top five states in the U.S with the largest Black/African American and Hispanic/Latino/a populations. Regarding race and ethnicity, 6 participants were Black/African American, 13 Hispanic/Latino/a, 1 Asian, 1 Native Hawaiian or Pacific Islander, and 9 White, with 95% female participants. This cohort had 90% program completion and 7 advocacy projects: 2 on lung cancer, 2 on pancreas cancer, and 3 on prostate cancer. Participants showed an increased in knowledge, from pre- mean 68.1 to post- mean 74.0, and a p-value of 0.018. There was an increased in self-efficacy; program satisfaction and evaluation were rated as high. In summary, our study depicts the effectiveness of a unique CSRA program tailored for Black/African American and Hispanic/Latino/a adults, fostering robust communication channels between cancer research advocates and diverse stakeholders. We emphasize the potential of such initiatives in addressing cancer health disparities and advocating to address specific inequalities by imparting educational initiatives in cancer research advocacy. We look forward to evaluating and enhancing our training program with an additional 21 research advocates in our cohort of 2024. Citation Format: Brooke Hensel, Ileana Guzman, Carolina Aristizabal, Eduardo Ibarra, Rosa Barahona, Lourdes Baezconde-Garbanati, Mariana C. Stern, Sandra Suther, Fern J. Webb. Community scientist research advocacy program: Training our research community [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B107.

Epidemiological Study and Seropositivity in Viral Panel Testing Among Corneal Tissue Donors.

Corneal tissue is a critical component for vision restoration through transplantation, yet the availability of suitable corneal tissue is limited. This limitation results in long waiting lists and high demand, especially in countries with lower donation rates compared to global benchmarks. In Mexico, the corneal donation rate remains significantly behind other Latin American countries and leading nations such as Spain. Understanding the characteristics of corneal tissue donors is essential for improving donation practices and addressing the shortage of available tissues. This descriptive retrospective study analyzed electronic medical records of cadaveric corneal donors at the General Regional Hospital 1 of the Mexican Social Security Institute of Querétaro from January 2022 to December 2023. Donors were included based on criteria such as age (2-85 years) and known cause of death. Exclusion criteria included age outside the specified range, neoplastic diseases, active systemic infections, and prior ocular surgeries. Serological testing for human immunodeficiency virus (HIV), Venereal Disease Research Laboratory (VDRL), coronavirus disease 2019 (COVID-19), hepatitis B virus (HBV), and hepatitis C virus (HCV was performed to assess viral reactivity. Statistical analyses were conducted usingIBM SPSS Statistics for Windows, Version 25 (Released 2017; IBM Corp., Armonk, New York, United States), summarizing data with descriptive statistics. The study included 185 corneal donors with a mean age of 56.34 years. The majority were male (109; 58.9%), and the leading causes of death were cardiogenic shock (34; 18.4%), hypovolemic shock (31; 16.8%), and acute respiratory failure (30; 16.2%). Exclusion due to positive serological tests included seven donors (3.8%) for HIV and seven (3.8%) for SARS-CoV-2. A total of 16 donors (8.6%) were excluded due to positive results in the viral serological panel. The most common comorbidities were chronic kidney disease (36; 19.5%), type 2 diabetes mellitus (28; 15.1%), and systemic hypertension (31; 16.8%). The study highlights a predominantly male donor profile with a mean age of 56.34 years and emphasizes cardiogenic shock as a leading cause of death. The notably higher seropositivity rate of 8.6% for various viral infections compared to international reports indicates a need for improved health interventions and screening processes. The focus on cardiovascular and respiratory causes of death underscores regional health issues affecting donation patterns. To address the organ and tissue donation shortfall, it is crucial to enhance coordination within donation teams and increase public awareness, given the significant gap in donation rates compared to leading countries.

Perspectives on Organ Donation among Adolescents and Impacting Factors

Organ donation is a pivotal yet relatively unexplored subject in India, where prevalent myths, misconceptions, and cultural beliefs often shape people's attitudes and perceptions towards organ donation. This research paper delves into the views of adolescents in India on organ donation, as they represent a crucial demographic group that is poised to become future decision-makers and potential donors. Based on a thorough analysis of qualitative and quantitative data collected through surveys, interviews, and focus group discussions, the paper examines the knowledge, attitudes, and intentions of adolescents regarding organ donation. Furthermore, the paper investigates the factors that influence their willingness to donate organs, including their religious and cultural beliefs, family dynamics, educational interventions, and awareness campaigns. The study's results provide valuable insights into the obstacles and enablers of organ donation among young people in India and underscore the significance of targeted educational programs to foster a donation culture and enhance organ donation rates in the country.

Japanese Perception of Brain Death and Implications for New Medical Technologies: Quantitative and Qualitative Social Media Analysis.

Brain death has been used to decide whether to keep sustained care and treatment. It can facilitate tissue, organ, and body donation for several purposes, such as transplantation and medical education and research. In Japan, brain death has strict diagnostic criteria and family consent is crucial, but it has been a challenging concept for the public since its introduction, including knowledge and communication issues. We analyzed data across YouTube and Twitter in Japan to uncover actors and assess the quality of brain death communication, providing recommendations to communicate new medical technologies. Using the keyword "" (brain death), we collected recent data from YouTube and Twitter, classifying the data into 5 dimensions: time, individuality (type of users), place, activity, and relations (hyperlinks). We employed a scale to evaluate brain death information quality. We divided YouTube videos into 3 groups and assessed their differences through statistical analysis. We also provided a text-based analysis of brain death-related narratives. Most videos (20/61, 33%) were uploaded in 2019, while 10,892 tweets peaked between July 3 and 9, 2023, and June 12 and 18, 2023. Videos about brain death were mostly uploaded by citizens (18/61, 27%), followed by media (13/61, 20%) and unknown actors (10/61, 15%). On the other hand, most identified users in a random sample of 100 tweets were citizens (73/100, 73%), and the top 10 retweeted and liked tweets were also mostly authored by citizens (75/100, 75%). No specific information on location was uncovered. Information videos contained guides for accreditation of the National Nursing Exam and religious points of view, while misinformation videos mostly contained promotions by spirituality actors and webtoon artists. Some tweets involved heart transplantation and patient narratives. Most hyperlinks pointed to YouTube and Twitter. Brain death has become a common topic in everyday life, with some actors disseminating high-quality information, others disseminating no medical information, and others disseminating misinformation. Recommendations include partnering with interested actors, discussing medical information in detail, and teaching people to recognize pseudoscience.

Vinyl-containing covalent organic frameworks co-polymerized with imidazolium ionic liquids for the efficient cycloaddition of CO2 with epoxides

The chemical fixation of CO2 into high value-added cyclic carbonates over metal- and cocatalyst-free heterogeneous catalyst has attracted considerable attention and is still a challenge. Rationally integrating multifunctional units into porous materials has been regarded as a promising strategy to enhance catalytic efficiency. In this study, the poly (ionic liquid)-hierarchical covalent organic framework (R-PIL-COF, R refers to CH2NH2/CH2OH/COOH/CH3) hybrids were successfully fabricated via in situ copolymerization of vinyl-containing covalent organic framework and hydrogen bond donors (HBDs)-functionalized imidazolium ionic liquids. Among, CH2NH2-PIL-COF hybrid bearing acidic and basic sites possess moderate CO2 adsorption ability and hierarchical pore structure which promoted the activation of CO2 and epichlorohydrin. Furthermore, the influence on the catalytic activity of various HBD groups and grafting amounts of poly (ionic liquid)s were systematically investigated, and CH2NH2-PIL–COF–45 % exhibited an exceptional catalytic performance under mild conditions (100 °C and 1 MPa CO2 pressure). Additionally, CH2NH2-PIL–COF–45 % had broad substrate tolerance and excellent stability. Finally, a synergistic catalytic mechanism was proposed based on the experimental and characterization results. The strategy of co-polymerizing ionic liquids to COF provides a new way to develop efficient COF-based hybrids by the integration of nucleophilic units into the COF skeleton for CO2 fixation under cocatalyst-free and mild conditions.

Nudging and the Safeguards of the Rule of Law

Abstract Nudging is a policy tool that steers people’s behavior through noncoercive psychological pushes. This has consequences for people’s lives to varying degrees. For example, the nudge of a sticker of a fly in a urinal encourages peeing inside a urinal, while an organ donation default brings people to agree to donating their organs after their decease. Governments do not yet systematically examine which nudges have to be subjected to all safeguards of the rule of law—for example, parliamentary control, judicial review, or compliance with legal principles such as proportionality. This article argues that a legal doctrine is necessary to carry out this examination. Moreover, it contributes to the development of such a doctrine, using the approach of the European Court of Human Rights as a source of inspiration. The doctrine consists of a “de minimis” principle for nudges: Public institutions only need to ensure that a nudge complies with rule of law safeguards when the nudge has substantial consequences. In addition, the doctrine includes a criterion to determine which nudges have such substantial consequences. In particular, it is argued that a nudge should be subjected to at least some safeguards when it has a serious effect on people’s autonomy.

Survival benefit of liver transplantation utilizing marginal donor organ according to ABO blood type.

The current liver transplantation (LT) allocation policy focuses on the Model for End-Stage Liver Disease (MELD) scores, often overlooking factors like blood type and survival benefits. Understanding blood types' impact on survival benefits is crucial for optimizing the MELD 3.0 classification. This study used the United Network for Organ Sharing national registry database (2003-2020) to identify LT characteristics per ABO blood type and to determine the optimal MELD 3.0 scores for each blood type, based on survival benefits. The study included LT candidates aged 18 years or older listed for LT (total N=150,815; A:56,546, AB:5,841, B:18,500, O:69,928). Among these, 87,409 individuals (58.0%) underwent LT (A:32,156, AB:4,362, B:11,786, O:39,105). Higher transplantation rates were observed in AB and B groups, with lower median MELD 3.0 scores at transplantation (AB:21, B:24 vs. A/O:26, p<0.01) and shorter waiting times (AB:101 days, B:172 days vs. A:211 days, O:201 days, p<0.01). A preference for Donation after Cardiac Death (DCD) was seen in A and O recipients. Survival benefit analysis indicated that B blood type required higher MELD 3.0 scores for transplantation than A and O (Donation after Brain Death transplantation: ≥15 in B vs. ≥11 in A/O; DCD transplantation: ≥21 in B vs. ≥11 in A, ≥15 in O). The study suggests revising the allocation policy to consider blood type for improved post-LT survival. This calls for personalized LT policies, recommending higher MELD 3.0 thresholds, particularly for individuals with type B blood.

Pushing the Survival Bar Higher: Two Decades of Innovation in Lung Transplantation.

Survival after lung transplantation has significantly improved during the last two decades. The refinement of the already existing extracorporeal life support (ECLS) systems, such as extracorporeal membrane oxygenation (ECMO), and the introduction of new techniques for donor lung optimization, such as ex vivo lung perfusion (EVLP), have allowed the extension of transplant indication to patients with end-stage lung failure after acute respiratory distress syndrome (ARDS) and the expansion of the donor organ pool, due to the better evaluation and optimization of extended-criteria donor (ECD) lungs and of donors after circulatory death (DCD). The close monitoring of anti-HLA donor-specific antibodies (DSAs) has allowed the early recognition of pulmonary antibody-mediated rejection (AMR), which requires a completely different treatment and has a worse prognosis than acute cellular rejection (ACR). As such, the standardization of patient selection and post-transplant management has significantly contributed to this positive trend, especially at high-volume centers. This review focuses on lung transplantation after ARDS, on the role of EVLP in lung donor expansion, on ECMO as a principal cardiopulmonary support system in lung transplantation, and on the diagnosis and therapy of pulmonary AMR.

Optimizing Corneal Transplant Safety: The Impact of Mandatory Prion Protein Testing on Iatrogenic Creutzfeldt-Jakob Disease Prevention in the Czech Republic.

The purpose of this study was to assess the effectiveness of legally mandated testing for pathogenic prion proteins in corneal tissue donors in the Czech Republic, considering its impact on safety, financial, and temporal costs. Between January 2007 and December 2023, standardized brain regions were collected from all corneal tissue donors in the Czech Republic. Tissue samples were tested for the presence of pathogenic prion proteins by the Czech Reference Laboratory for Human Prion Diseases. The testing used a Western blot analysis, using 2 distinct monoclonal anti-PrP antibodies. A total of 8030 donors were tested. Four tested samples were initially weakly positive. Subsequent testing conclusively determined these samples to be negative. The remaining 8026 tests yielded negative results confirming the safety of donor screening. We did not observe any cases of proven transmissible spongiform encephalopathies (TSEs). TSE testing has consistently confirmed that no patients with TSE have been selected into the corneal donor pool, solidifying the effectiveness of the active surveillance program and exclusion criteria. We propose that these mechanisms effectively prevent patients with TSEs from being included in the corneal tissue donor pool. However, the substantial financial costs and a 2-day delay in processing pose challenges, contributing to graft nonutilization and potential negative impacts on patients in acute need. Moreover, the unique requirement for pathogenic prion testing in the Czech Republic also makes importing any corneal grafts from other countries impossible, as those tissues do not fulfill Czech legal requirements.

Deceased Organ Donor HTLV Screening Practices Postelimination of Universal Screening in the United States.

In the United States, universal screening for human T-lymphotropic virus (HTLV) in deceased organ donors was discontinued in 2009. Since then, the transplant guideline suggests considering targeted screening. However, the outcomes of this change in HTLV screening have not been evaluated. Using the Organ Procurement and Transplantation Network database between 2010 and 2022, we analyzed the HTLV antibody screening frequency and seroprevalence in potential deceased organ donors and their correlations with HTLV infection risks, including race and high-risk behaviors for blood-borne pathogen infection. Although targeted screening has not been established for HTLV, we hypothesized that screening rates should correlate with the proportions of donors with infection risk if screening is targeted. We also evaluated the organ utilization of HTLV-seropositive donors. Of 130 284 potential organ donors, 22 032 (16.9%) were tested for HTLV antibody. The proportion of donors tested for HTLV varied between Organ Procurement Organizations (median [interquartile range], 3.8% [1.0%-23.2%]; range, 0.2%-99.4%) and was not correlated to HTLV infection risks. There were 48 seropositive donors (0.22%), and at least 1 organ from 42 of these donors (87.5%) was transplanted. The number of organs recovered and transplanted per donor was significantly lower in HTLV-seropositive than in HTLV-negative donors (recovered, 2 [2-3] versus 3 [3-5], P < 0.001; transplanted, 2 [1-3] versus 3 [2-4], P < 0.001). However, HTLV-1 infection was not attributed as the cause of nonrecovery except for only 1 HTLV-seropositive donor. HTLV screening practices varied across the United States. Our findings suggest that targeted screening was not performed after the elimination of universal screening.

Racial Equity in Family Approach for Patients Medically Suitable for Deceased Organ Donation.

To conduct a contemporary analysis of the association between family approach of medically suitable potential organ donors and race/ethnicity. Retrospective review of data collected prospectively by Organ Procurement Organizations (OPOs). Ten OPOs representing eight regions of the Organ Procurement and Transplantation Network and 26% of all deceased donor organs recovered in the United States. All hospitalized patients on mechanical ventilation and referred to OPOs as potential donors from January 1, 2018, to December 31, 2022. None. OPOs provided data on referral year, race, sex, donor registration status, screening determination, donation medical suitability, donation type (brain death, circulatory death), and family approach. We evaluated factors associated with family approach to discuss donation using descriptive statistics and multivariable logistic models. Of 255,429 total cases, 138,622 (54%) were screened-in for further evaluation, with variation by race/ethnicity (50% White, 60% Black, 69% Hispanic, and 60% Asian). Among those screened-in, 31,253 (23%) were medically suitable for donation, with modest variation by race/ethnicity (22% White, 26% Black, 23% Hispanic, and 21% Asian). Family approach rate by OPOs of medically suitable cases was 94% (n = 29,315), which did not vary by race/ethnicity (94% White, 93% Black, 95% Hispanic, and 95% Asian). Family approach by OPOs was lower for circulatory death (95%) vs. brain death (97%) cases but showed minimal differences in approach rate based on race/ethnicity between medically suitable patients with different death pathways. In contrast, donor registration status of medically suitable potential donors was highly variable by race/ethnicity (37% overall; 45% White, 21% Black, 29% Hispanic, and 25% Asian). Multivariable models indicated no significant difference of family approach between White and Black (odds ratio [OR], 1.09; 95% CI, 0.95-1.24) or Asian (OR, 1.23; 95% CI, 0.95-1.60) patients. Findings indicate racial equity in OPO family approach rates among patients who were medically suitable for organ donation.

Efficient decellularization of human fetal kidneys through optimized SDS exposure

Chronic kidney disease poses a significant threat to public health. Renal replacement therapy is the primary treatment option for end-stage kidney disease. However, there is a promising and relatively new method in regenerative medicine for creating a functional organ known as whole kidney decellularization. This method uses the intrinsic vasculature to perfuse the decellularizing agent into the tissue, effectively penetrating and removing cellular material. The regenerated bioscaffolds could serve as a source of organ donation. This study is focused on evaluating the effectiveness of various SDS exposures in decellularizing human fetal kidneys. The study included human fetal kidneys harvested from fetuses terminated before 14 weeks of gestational age. Kidneys were divided into six treatment groups based on SDS concentration and duration of perfusion. Decellularization, scanning electron microscopy, histopathological staining, immunofluorescent staining, and immunohistochemistry staining were performed to evaluate the adequacy of the process. The statistical analysis revealed that the SDS 0.1% treatment group had the highest collagen deposition after 24 h, significantly greater than the SDS 0.5% treatment group at 24 and 48 h. No significant differences were observed among the other treatment groups. The study concludes that the SDS 0.1% treatment group for 24 h was the most effective in terms of ECM content preservation and effective cell removal. This treatment showed better results than the other treatment groups and can be considered for future whole kidney decellularization studies.

Immune perturbations in human pancreas lymphatic tissues prior to and after type 1 diabetes onset.

Autoimmune destruction of pancreatic β cells results in type 1 diabetes (T1D), with pancreatic immune infiltrate representing a key feature in this process. Studies of human T1D immunobiology have predominantly focused on circulating immune cells in the blood, while mouse models suggest diabetogenic lymphocytes primarily reside in pancreas-draining lymph nodes (pLN). A comprehensive study of immune cells in human T1D was conducted using pancreas draining lymphatic tissues, including pLN and mesenteric lymph nodes, and the spleen from non-diabetic control, β cell autoantibody positive non-diabetic (AAb+), and T1D organ donors using complementary approaches of high parameter flow cytometry and CITEseq. Immune perturbations suggestive of a proinflammatory environment were specific for T1D pLN and AAb+ pLN. In addition, certain immune populations correlated with high T1D genetic risk independent of disease state. These datasets form an extensive resource for profiling human lymphatic tissue immune cells in the context of autoimmunity and T1D.

Abstract A057: Investigating Fibroblast-Epithelial crosstalk in pre-malignant and cancerous microenvironment

Abstract Pancreatic ductal adenocarcinoma (PDAC) originates from precursor lesions, the most common of which are known as pancreatic intraepithelial neoplasia (PanIN). PanIN formation and progression is accompanied by accumulation of a precursor microenvironment (PME) composed of desmoplastic stroma that plays an important role in promoting tumor growth and immune evasion. The crosstalk between tumor cells and stromal cells is an area of active investigation. While PanIN and the PME have been extensively studied in mouse models, their nature in humans have remained elusive as there is no clinical indication to sample healthy pancreas. Through a unique collaboration with the Gift of Life Organ and Tissue donation program, we performed transcriptomic analysis on normal pancreata declined for transplant. We noted that epithelial cells in the PanIN and cancer microenvironment were transcriptomically similar; however, their surrounding stromal fibroblasts were markedly distinct. Given that most precursor lesions remain quiescent while some progress to tumor, we sought out to elucidate how the transcriptional programs in epithelial cells influence fibroblast cell fate. To do so, we developed a 3D ex-vivo organoid-fibroblast coculture system using primary organoid and fibroblast cultures successfully derived from Gift of Life pancreata or PDAC patients undergoing surgical resection. Our coculture system retains histological features of heterogeneity observed in vivo. Using single cell RNA-sequencing analysis of matched fibroblast-organoid cocultures we identified factors that were highly expressed in fibroblasts in tumor cocultures, but not in normal cocultures. We are currently interrogating candidate ligand/receptor interactions in our cocultures to determine the mediators of this epithelial-mediated fibroblast polarization. This model will allow us to gain an understanding about how components of the microenvironment restrain or promote malignant transformation and serve as a great tool to study therapies targeting tumor and stromal cells in a patient specific manner. Citation Format: Padma Kadiyala, Ahmed Elhossiny, Jianhua Liu, Alexander Bray, Katelyn Donahue, Arvind Rao, Jiaqi Shi, Yaqing Zhang, Filip Bednar, Timothy Frankel, Eileen Carpenter, Marina Pasca Di Magliano. Investigating Fibroblast-Epithelial crosstalk in pre-malignant and cancerous microenvironment [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A057.

Abstract A046: Spatial transcriptomics reveals heterogeneity of epithelial and stromal compartments in healthy and tumor pancreas

Abstract Pancreatic Ductal Adenocarcinoma (PDAC) is one of the most lethal cancers, with a 5-year survival rate of only 13%. PDAC develops from precursor lesions, most commonly Pancreatic Intraepithelial Neoplasia (PanIN). Studying PanIN in human patients is difficult due to its microscopic nature and the lack of indication for sampling the pancreas in the absence of disease. In collaboration with Gift of Life - Michigan, a local organ and tissue donor organization, we obtained over 80 pancreata for research. Surprisingly, we found PanIN in the vast majority of the organs, regardless of the donor’s age; the prevalence of PanIN compared to the relatively low incidence of PDAC indicates that most lesions are destined not to progress. To gather insight into factors that might distinguish lesions designed to progress from lesions that are likely to remain dormant, we sought to characterize both epithelial cells and their supporting microenvironment. Using spatial transcriptomics, we determined that PanIN epithelial cells are transcriptionaally similar to pancreatic cancer; further, limited genetic characterization revealed that they contain similar oncogenic KRAS mutations as pancreatic malignancy. We then sought to determine whether factors in the microenvironment distinguish sporadic PanIN from those associated with overt malignancy. We used 10x Genomic CytAssist Visium technology and profiled an initial batch of 7 tissue sections from donor pancreata and an equal number from tumors. We employed the BayesPrism algorithm to deconvolute the Visium data (which lacked single-cell resolution), using our single-cell RNAseq atlas to define stroma- and epithelial-specific expression profiles. We then segmented the tissue into epithelial and stromal compartments. We further identified various stromal subpopulations, with macrophages and fibroblasts being the most abundant cell types. We defined subpopulations of epithelial cells, fibroblasts, and macrophages through unsupervised clustering. In both donor samples and tumors, we identified heterogeneous populations of stromal cells present in specific geographic patterns, with PanIN-adjacent stroma clearly distinct from stroma surrounding healthy ducts. Cell-cell neighborhood analysis revealed a distinct geographic arrangement of epithelial and stromal compartments, indicating potential communication patterns. Independent unsupervised statistical analysis using Non-negative Matrix Factorization (NMF) using Coordinated Gene Association in Pattern Sets (CoGAPS) R package also revealed similar patterns. Our next steps involve validating gene expression signatures that define each subpopulation and identifying tumor-specific or PanIN-specific genes. Ultimately, we aim to investigate interactions between epithelial cells, fibroblasts, and macrophages to identify potential tumor-promoting or tumor-restraining pathways. Citation Format: Ahmed M. Elhossiny, Jude Okoye, Imade Williams, Yaqing Zhang, Hannah Watkoske, Atul Deshpande, Elana Fertig, Arvind Rao, Eileen S. Carpenter, Timothy L. Frankel, Marina Pasca di Magliano. Spatial transcriptomics reveals heterogeneity of epithelial and stromal compartments in healthy and tumor pancreas [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A046.

Abstract C076: Transcriptomic analyses of normal human pancreatic acinar cells reveal the presence of cancer subtypes that correlate with acinar ductal metaplasia

Abstract Gene expression subtypes exist in pancreatic ductal adenocarcinoma (PDAC), however comparable subtypes are not known to exist in normal human pancreas. Our laboratory has collected a large (N=55) and racially diverse (14 Black, 27 White and 14 Hispanic) cohort of normal human pancreatic acinar cell specimens that were processed at islet transplantation centers. Deceased organ donors were maintained on life support until the time the pancreas was surgically removed. Samples of primary, uncultured (Day 0) or ADM transdifferentiated (Day 6) normal pancreatic acinar cells were subjected to bulk transcriptomic sequencing. UMAP analysis of the transcriptomic data from the Day 0 samples revealed the presence of two distinguishable clusters of data that we arbitrarily refer to as Group 1 (n = 31) and Group 2 (n = 24). Heatmaps of the expression of 57 genes belonging to the exocrine-like, classical and basal subtypes produced a clear separation of the data. Since the exocrine-like genes increased in Group 1 and the basal and classical genes increased in Group 2, we refer to Group 1 as the exocrine-like subtype and Group 2 as the basal/classical subtype. The basal/classical subtype samples showed greater morphological and molecular acinar ductal metaplasia compared to those in the exocrine-like subtype. When stratified by demographics and subtype, volcano plots revealed a striking trend with Blacks, women, obese and younger individuals having significantly fewer differentially expressed genes (basal/classical vs exocrine-like) compared to Hispanics, men, nonobese and older individuals. Our data demonstrate that, similar to PDAC, normal pancreatic acinar cells are distinguishable by gene subtypes. Moreover, the gene expression ratio of these subtypes varies dramatically by donor demographics. Citation Format: Corey M Perkins, Jinmai Jiang, Zachary Greenberg, Md Abu Talha Siddique, Linda C Williams, Jason O Brant, Kalyanne Shirlekar, Bo Han, Jamel Ali, Kristianna M Fredenburg, Kiley Graim, Diana J Wilkie, Mei He, Thomas D Schmittgen. Transcriptomic analyses of normal human pancreatic acinar cells reveal the presence of cancer subtypes that correlate with acinar ductal metaplasia [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr C076.

Detection of enterovirus RNA in pancreas and lymphoid tissues of organ donors with type 1 diabetes.

The nPOD-Virus group collaboratively applied innovative technologies to detect and sequence viral RNA in pancreas and other tissues from organ donors with type 1 diabetes. These analyses involved the largest number of pancreas samples collected to date. We analysed pancreas, spleen, pancreatic lymph nodes, and duodenum samples from the following donor groups: a) donors with type 1 diabetes (n=71), with (n=35) or without (n=36) insulin-containing islets, (b) donors with single or double islet autoantibody positivity without diabetes (n=22) and c) autoantibody-negative donors without diabetes (control donors) (n=74). Five research laboratories participated in this collaborative effort using approaches for unbiased discovery of RNA viruses (two RNA-Seq platforms), targeted detection of Enterovirus A-D species using RT-PCR, and tests for virus growth in cell-culture. Direct RNA-Seq did not detect virus signal in pancreas samples, whereas RT-PCR detected enterovirus RNA confirmed by sequencing in low amounts in pancreas samples in three of the five donor groups, namely donors with type 1 diabetes with insulin-containing islets, 16% (5/32) donors being positive, donors with single islet autoantibody positivity with 53% (8/15) donors being positive, and non-diabetic donors with 8% (4/49) being enterovirus RNA positive. Detection of enterovirus RNA was significantly more frequent in single islet autoantibody-positive donors compared to donors with type 1 diabetes with insulin-deficient islets (p-value <0.001) and control donors (p-value 0.004). In some donors, pancreatic lymph nodes were also positive. RT-PCR detected enterovirus RNA also in spleen of a small number of donors and virus enrichment in susceptible cell lines before RT-PCR resulted in much higher rate in spleen positivity, particularly in donors with type 1 diabetes. Interestingly, the enterovirus strains detected did not cause a typical lytic infection, possibly reflecting their persistence-prone nature. This was the largest coordinated effort to examine the presence of enterovirus RNA in pancreas of organ donors with type 1 diabetes, using a multitude of assays. These findings are consistent with the notion that both the subjects with type 1 diabetes and those with islet autoantibodies may carry a low-grade enterovirus infection in the pancreas and lymphoid tissues.

Engraftment of wild-type alveolar type II epithelial cells in surfactant protein C deficient mice.

Childhood interstitial lung disease (chILD) secondary to pulmonary surfactant deficiency is a devastating chronic lung disease in children. Clinical presentation includes mild to severe respiratory failure and fibrosis. There is no specific treatment, except lung transplantation, which is hampered by a severe shortage of donor organs, especially for young patients. Repair of lungs with chILD represents a longstanding therapeutic challenge but cell therapy is a promising strategy. As surfactant is produced by alveolar type II epithelial (ATII) cells, engraftment with normal or gene-corrected ATII cells might provide an avenue to cure. Here we used a chILD disease-like model, Sftpc -/- mice, to provide proof-of-principle for this approach. Sftpc -/- mice developed chronic interstitial lung disease with age and were hypersensitive to bleomycin. We could engraft wild-type ATII cells after low dose bleomycin conditioning. Transplanted ATII cells produced mature SPC and attenuated bleomycin-induced lung injury up to two months post-transplant. This study demonstrates that partial replacement of mutant ATII cells can promote lung repair in a mouse model of chILD-like disease.