Abstract INTRODUCTION: For analysis of circulating cell-free DNA (ccfDNA) in cancer screening or monitoring, specialized blood collection tubes - such as the PAXgene® Blood ccfDNA Tube (PreAnalytiX) - offer a reliable solution for users who are unable to process samples within 4 hours of collection. These tubes stabilize ccfDNA profiles by preventing blood cells from releasing genomic DNA (gDNA) during transport, thereby preserving sample integrity for sensitive downstream ccfDNA analyses. According to international standards and regulations (ISO 20186-3:2019, (EU) 2017/746 on In Vitro Diagnostic Medical Devices) preanalytical conditions like sample collection, transport, and storage must be validated to ensure that the quality of ccfDNA is maintained. Here, we evaluated sample packaging, temperature fluctuations during transit, and the impact of shipment on downstream assay performance to assess whether blood samples in PAXgene tubes can be transported at ambient temperature. METHODS: Blood was collected from 30 apparently healthy consented donors into PAXgene Blood ccfDNA Tubes. Filled tubes were processed within 4 hours after phlebotomy or stored refrigerated (2-8°C), at 15°C or at room temperature (15-25°C) for 10 days and at 30°C for 7 days. For international transport tubes were shipped from the collection site (QIAGEN, Hilden, Germany) to an external processing site (BD, Franklin Lakes, USA). Samples were placed in insulated boxes compliant with IATA standards and without active temperature control. This included a leakproof triple packaging concept with a primary receptacle, a secondary package, and a rigid outer package. Upon arrival, blood samples were processed directly or subjected to an additional transport simulation test according to requirements defined in the standard ASTM D4169. Plasma and cellular fraction were separated, frozen and shipped back to QIAGEN for ccfDNA and gDNA extraction and analysis. RESULTS: Temperature fluctuations during transport were in the range of 18-35°C during summer and 7-25°C during winter. Additional drop, vibration and altitude tests to simulate transportation by truck, rail and air did not compromise yield or quality of DNA. The relative yield of ccfDNA from plasma, measured by qPCR, between samples processed immediately and after storage or transport and simulation was only slightly increased with mean values between 1.0- to 1.3-fold. gDNA yield and purity measured by spectrophotometry were high for all conditions in the range of 26 to 55 µg of gDNA per mL of cellular fraction and mean 260/280 ratios between 1.80 and 1.82. CONCLUSION: Excellent sample stability could be demonstrated in whole blood samples collected into PAXgene Blood ccfDNA Tubes under both controlled storage and real-world transport conditions. The data confirm that sample integrity is maintained following air and ground transportation at ambient temperatures across both summer and winter seasons. Citation Format: Daniel Grölz, Markus Wolf, Daniela Mancarella-Langer, Franziska Kaiser, Michelle Walther, Eric Provencer. Transport under various conditions: Evaluating blood sample stability across seasons [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7830.
Introduction: Peripheral arterial disease (PAD) disproportionately affects underserved populations, often leading to preventable amputations due to inadequate early intervention services. This project is to identify population segments with high PAD-related amputation risk and inadequate intervention services, enabling more targeted outreach and resource planning. Hypothesis: Counties with higher socioeconomic deprivation and adverse health indicators (e.g., high diabetes prevalence, smoking rates) will exhibit disproportionately higher PAD-related amputation risk and lower intervention rates compared to counties with more favorable social and health profiles . Methods: We developed a machine learning model to estimate PAD-related amputation risk using publicly available variables, including Area Deprivation Index (ADI), racial demographics, diabetes and obesity prevalence, smoking rates, food environment index, and uninsured rates. PAD intervention rates were calculated for every U.S. County using proprietary data sources. Each county was then categorized by amputation risk (“Well Below Average” to “Well Above Average”) and intervention rate (“No PAD Intervention Market” to “Well Above Average”). Results: An interactive heatmap was created to visualize all 3,146 U.S. counties, allowing users to explore 30 population segments based on their amputation risk and intervention rate. Segment-based filtering dynamically updates the map, providing a detailed view of counties within each category and offering insights into potential contributing factors. Conclusions: This tool offers a scalable and intuitive solution for identifying geographic and demographic areas where PAD interventions may be most urgently needed. Knowing where these regions are allows us to make more informed decisions around outreach with state and local organizations, and resource allocation regarding free PAD screening services and awareness education, which in turn, can contribute to improving patient outcomes and reducing preventable amputations. Future enhancements may include integrating patient-level data from specific organizations to help intervention providers assess and optimize their service performance.
Abstract Introduction Single-cell profiling has evolved to simultaneously capture mRNA, surface proteins, and immune receptor repertoires. However, challenges such as low-abundance transcript detection, sequencing cost, and background noise from unbound antibodies continue to limit assay performance. Methods We present an updated plate-based workflow featuring WTA NEXT, a high-sensitivity whole transcriptome analysis (WTA) assay that significantly improves gene and molecule recovery per cell. Benchmarking against the previous WTA version demonstrated a 27% increase in median genes per cell and a 30% gain in median molecules per cell. These improvements enhance cell classification resolution, rare transcript detection, and overall assay efficiency. Results Combined with modular lyophilized antibody panels–available for T, B, NK, tumor, and antigen-presenting cells –WTA NEXT supports flexible multiomic profiling. Researchers can tailor experiments using different panel combinations, and the format allows drop-ins without affecting performance when additional markers are needed. Conclusion The plate-based format enables post-capture washes to reduce ambient antibody background, while signal-dampening strategies improve detection of low-abundance proteins. The updated full-length TCR/BCR (VDJ) assay offers increased sensitivity for low abundance clonotypes, enabling robust repertoire profiling. When integrated with transcript and protein data, this assay reveals deeper insight into clonal expansion, cell state, and functional diversity. Together, these innovations deliver a sensitive, modular, and cost-efficient workflow for high-content single-cell immune profiling. Funding Source n/a Topic Categories Technological Innovations in Immunology (TECH)
