2024 · The Japanese dental science review · open access
Optimal storage time and temperature of human oral samples to minimize microbiome changes: A scoping review
Kim et al.
The finding, in our words
The review found that oral microbiome samples are best frozen immediately at -80 °C or lower, with storage not exceeding one to two years. For decentralised collection, samples may be held at room temperature for one to two weeks in appropriate media, informing self-collection protocols and transport logistics.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
Saliva samples collected using the OMNIgene ORAL device and oral wash samples remain stable for microbiome diversity and relative abundance analyses for up to five years when stored at -80°C. This supports the use of these self-collection methods for long-term prospective biobanking and decentralised clinical studies.
Slack et al., Microbiology spectrum (paywalled) · source ↗
This study found that a decontamination pipeline using metagenome-assembled genomes improves the accuracy of variant calling from saliva samples, showing superior concordance with blood-derived results compared to conventional methods. These results validate the potential of self-collected oral samples for accurate personal genotyping.
An analysis of 88 individuals aged 7 to 18 years found that stimulated saliva collection detected disease-associated microbiome taxa that unstimulated sampling missed. The authors note that sampling protocols must be standardised before results can be compared across decentralised studies.
Across 18 saliva samples, mouthwash collection gave higher alpha diversity than passive drooling on both Illumina and Nanopore platforms, and three preservation methods performed alike; mouthwash and simple collection are convenient decentralised options, provided a study keeps one collection method for all participants to avoid confounding.
Fecal and oral microbiome samples showed high stability over two years at -80°C, with intraclass correlation coefficients of 0.70–0.99 for stool and above 0.74 for saliva across most collection methods. Stool collected without additive and saliva collected with Scope mouthwash showed lower stability for some measures, demonstrating that collection method choice affects reliability of stored samples for microbiome analysis in decentralised diagnostics.
Zouiouich et al., Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology (paywalled) · source ↗