Transcriptomic and proteomic analysis of monocytic cells provides the evidence that cfDNA contained in plasma of healthy individuals regulates innate immune response - 11th International Symposium on Circulating Nucleic Acids in Plasma and Serum (CNAPS)

Marie Korabecna ^1,2 Iva Brynychova ¹ Alzbeta Zinkova ¹ Blanka Chylikova ¹ Lucie Sedova ¹ Ondrej Seda ^1,2 Petr Prikryl ³

¹Institute of Biology and Medical Genetics of the 1st Faculty of Medicine, Charles University and General University Hospital in Prague, Charles University, Prague, Czech Republic
²Institut of Biology and Medical Genetics of the 1st Faculty of Medicine and General University Hospital in Prague, General University Hospital in Prague, Prague, Czech Republic
³Institut of Pathological Physiology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic

Introduction: Recent study focused on exploration of effects of cfDNA isolated from blood products revealed the cfDNA affects innate immune system (Abramowski S. W. et al. 2018). We decided to study how the cfDNA contained in plasma of healthy individuals influenced transcriptome and proteome of THP 1 monocytic cell line.

Material and Methods: Using the cultivation of THP1 monocytic cells with paired samples of plasma (native - NP, and treated by DNase - TP), we analysed the contribution of cfDNA to the alteration of gene expression. We used plasma samples of ten healthy volunteers. We employed GeneChip (HuGene 2.1 ST Array Strip, AppliedBiosystems) and validated the results for the 11 most altered genes by quantitative PCR. Proteomic analysis was performed using nano-UHPLC-MS system.

Results: GeneChip analysis detected 26 trancripts with significantly different expression levels between cells cultivated with NP and with TP (p-value ≤0.05, ≤-2 fold change ≥2). Validation proved significantly higher expression of TXNIP, ARRDC4, HERPUD1, IRF1, DDIT3, HES 1 and SESN2 in cells cultivated with NP, and significantly higher expression of GPR183, CCL24, CXXL8 and MTSS1 in cells cultivated with TP. The database Reactome revealed that among the highly affected biological events in cells cultivated with TP are Interleukin and Cytokine Signaling Pathways. The mass spectrometric analysis identified nearly 3000 proteins from which about seventy had significantly different levels in cells treated with NP and with TP. The prominent feature detected by Reactome in cells cultivated with TP was the Activation of Complement .

Conclusion: Our pilot study provides the evidence for existence of important links between the self cfDNA sensing and regulation of innate immune response.

Supported by grant Progres Q25/LF1 of the Ministry of Education, Youth and Sport of the Czech Republic, and by the grant RVO-VFN 64165 of the Ministry of Health of the Czech Republic.