Abstract Objective:Whole genome sequencing (WGS) can help identify transmission of pathogens causing healthcare-associated infections (HAIs). However, the current gold standard of short-read, Illumina-based WGS is labor and time intensive. Given recent improvements in long-read Oxford Nanopore Technologies (ONT) sequencing, we sought to establish a low resource approach providing accurate WGS-pathogen comparison within a time frame allowing for infection prevention and control (IPC) interventions. Methods:WGS was prospectively performed on pathogens at increased risk of potential healthcare transmission using the ONT MinION sequencer with R10.4.1 flow cells and Dorado basecaller. Potential transmission was assessed via Ridom SeqSphere+ for core genome multilocus sequence typing and MINTyper for reference-based core genome single nucleotide polymorphisms using previously published cutoff values. The accuracy of our ONT pipeline was determined relative to Illumina. Results:Over a six-month period, 242 bacterial isolates from 216 patients were sequenced by a single operator. Compared to the Illumina gold standard, our ONT pipeline achieved a mean identity score of Q60 for assembled genomes, even with a coverage rate as low as 40×. The mean time from initiating DNA extraction to complete analysis was 2 days (IQR 2–3.25 days). We identified five potential transmission clusters comprising 21 isolates (8.7% of sequenced strains). Integrating ONT with epidemiological data, >70% (15/21) of putative transmission cluster isolates originated from patients with potential healthcare transmission links. Conclusions:Via a stand-alone ONT pipeline, we detected potentially transmitted HAI pathogens rapidly and accurately, aligning closely with epidemiological data. Our low-resource method has the potential to assist in IPC efforts. 
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                            HLA-PopSeq: High throughput, multiplexed six-locus Human Leukocyte Antigen typing for population-scale T cell immune profiling using rapid long-read nanopore sequencing
                        
                    
    
            Abstract A major technical hurdle for T cell immune profiling is the time and cost to accurately genotype the Human Leukocyte Antigen (HLA) loci from peripheral blood. Here, we developed a rapid, highly multiplexed approach for HLA typing using RNA from <100,000 peripheral blood mononuclear cells with the Oxford Nanopore Technology (ONT) Minion sequencer. This method uses selective reverse transcription of mRNA of six HLA loci (A,B,C, DRB1, DQB1, DPB1), followed by PCR amplification. The individual amplified HLA cDNA was multiplexed in a single sequencing pool using primers with unique molecular identifiers, designed to permit sequencing errors for enhanced data capture. Pooled HLA amplicons were sequenced using the ONT Minion MK1B and R10.4 flowcells, with sequence Q scores> 20. Total RNA was extracted from PBMC samples from 12 individuals, reverse transcribed and amplified using the designed HLA loci specific primers. The pooled, amplified cDNA was then sequenced for 16 hours on the ONT Minion sequencer. The resulting sequencing data was analyzed and an average depth of coverage of 6000x was observed per sample. An average per loci depth of coverage of 1000x was observed. This method is designed to permit rapid (<24h), low-cost, portable HLA sequencing for T cell immune monitoring and epitope identification for immunologic studies. Arizona Piper Foundation 
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                            - Award ID(s):
- 2152254
- PAR ID:
- 10516542
- Publisher / Repository:
- Journal of Immunology
- Date Published:
- Journal Name:
- The Journal of Immunology
- Volume:
- 210
- Issue:
- 1_Supplement
- ISSN:
- 0022-1767
- Page Range / eLocation ID:
- 250.10 to 250.10
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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