An internal pilot study of a novel rectal mucocellular sampling device to allow next-generation sequencing for colorectal disease.

BACKGROUND: The ORI-EGI-02 study was designed to test the hypothesis that rectal mucus collected using a novel rectal sampling device (OriCol™), contains sufficient human deoxyribonucleic acid (DNA) of the required quality for Next Generation Sequencing (NGS), for colorectal disease genetic signature discovery. METHODS: Using National Institute for Health and Care Research methodology, an internal pilot study was performed in January 2020-May 2021, at four sites in the United Kingdom, to assess the process of recruitment, consent, specimen acquisition and viability for analysis. Following an OriCol™ test, the sample was stabilized with a buffer solution to preserve the material, which was posted to the laboratory. Samples were processed using QIAamp® DNA Blood Midi kit to extract DNA and Quant-iT™ PicoGreen® dsDNA Reagent to quantify the retrieved DNA. DNA integrity was measured by Agilent TapeStation system. 25 ng of human amplifiable DNA was prepared for Next Generation Sequencing (NGS), which was performed on an Illumina NextSeq550 sequencer using the 300-cycle high output kit v2.5. RESULTS: This study assessed the first 300 patients enrolled to the ORI-EGI-02 Study (n = 800). 290/300 (96.67%) were eligible to undergo OriCol™ sampling procedure and 285/290 (98.27%) had a successful OriCol™ sample taken. After transportation, extraction and quantification of DNA, 96.20% (279/290) of the samples had NGS successfully performed for bioinformatic analysis. CONCLUSIONS: Our internal pilot study demonstrated that the OriCol™ sampling device can capture rectal mucus from unprepared bowel in subjects who could undergo a digital rectal examination. The technique could be applied irrespective of age, frailty, or co-morbidity. Completion of the study to 800 patients and analysis of NGS data for colorectal cancer mutations will now proceed.

A novel TNFRSF1A splice mutation associated with increased nuclear factor kappaB (NF-kappaB) transcription factor activation in patients with tumour necrosis factor receptor associated periodic syndrome (TRAPS).

OBJECTIVE: To characterise and investigate the functional consequences of a novel TNFRSF1A splice site mutation causing tumour necrosis factor receptor associated periodic syndrome (TRAPS) in a 16-year-old male patient and his mother. METHODS: Mutational DNA screening was performed in the patient and his mother. Western blotting was used to analyse protein expression levels of TNFR1. A multiplex bead immunoassay was used to quantify serum levels of range of cytokines, and an ELISA-based transcription factor assay to measure nuclear factor (NF)-kappaB transactivation. Serum levels of soluble TNFR1 (sTNFR1) were measured by ELISA and fluorescence-activated cell sorting (FACS) analysis used to measure monocyte TNFR1 cell surface expression. RESULTS: A novel mutation, c.472+1G>A (C158delinsYERSSPEAKPSPHPRG), involving a splice site in intron 4 of TNFRSF1A, was found in the proband and affected mother leading to a 45 nucleotide insertion of intronic DNA into the mRNA, resulting in an in-frame insertion of 15 amino acids in the mature TNFR1 protein and a deletion of a cysteine residue C129 (158) in cysteine rich domain (CRD)3. The patients had reduced serum sTNFR1 and surface expression levels of TNFR1, with marked increases in pro- and anti-inflammatory cytokine. Their peripheral blood mononuclear cells (PBMC) had increased basal NF-kappaB activation compared with healthy controls and also had increased p50 nuclear expression following tumour necrosis factor (TNF) stimulation compared with PBMC from healthy controls, as well as T50M (T79M) and C88R (C117R) patients with TRAPS and patients with rheumatoid arthritis (RA). CONCLUSION: A novel, TRAPS causing, TNFRSF1A splice site mutation is associated with decreased sTNFR1 levels, cell surface and whole cell extract expression and increased NF-kappaB transcription factor activation.