Impact of storage conditions on peripheral leukocytes transcriptome

Area of Science:

• Molecular Biology
• Genomics
• Hematology

Background:

• Leukocytes are crucial indicators of health status.
• Leukocyte transcriptomic data offers insights into physiological and pathological conditions.
• The impact of pre-analytical ex vivo storage on leukocyte transcriptomes is not fully understood.

Purpose of the Study:

• To investigate the influence of temporary storage conditions on the leukocyte transcriptome.
• To determine optimal blood storage conditions for preserving leukocyte gene expression integrity.

Main Methods:

• Peripheral blood samples were stored at 4°C or room temperature (RT) for varying durations (2h, 6h, 24h).
• RNA sequencing was performed on extracted leukocyte RNA.
• Weighted gene co-expression network analysis and Gene Ontology (GO) term enrichment were applied.

Main Results:

• Storage conditions significantly alter peripheral leukocyte gene expression.
• 24h storage at 4°C affected 1.51% of genes, while RT storage affected 10.82%.
• Nucleosome assembly was enriched in upregulated genes under both storage conditions; RT storage induced changes in apoptosis, cell cycle, and lymphocyte activation pathways.

Conclusions:

• Temporary storage conditions profoundly impact leukocyte gene expression profiles, potentially altering cell viability and state.
• Storage at 4°C for up to 6 hours is recommended to largely maintain the original leukocyte transcriptome.