Potential capacity of aptamers to trigger immune activation in human blood

ABSTRACT: Target specific short single-stranded DNA (ssDNA) molecules, called aptamers, are auspicious ligands for numerous in vivo applications. However, aptamers are synthetic molecules, which might be recognized by the immune cells in vivo and induce an activation of the innate immune system. Thus, immune activation potential of synthetic ssDNA oligonucleotides (ODNs) was determined using a well established closed-loop circulation model. Fresh human blood was incubated at 37°C for 2 or 4 hours with ssDNA ODNs (SB_ODN) or CpG ODN as positive control. Transcriptional changes were determined by microarray analyses. Blood samples containing SB_ODN demonstrated after 4 hours a significant regulation of 295 transcripts. Amongst others, CCL8, CXCL10, CCL7 and CXCL11 were highest regulated genes. Gene Ontology terms and KEGG pathway analyses exhibited that the differentially expressed genes belong to the transcripts that are regulated during an immune and inflammatory response, and were overrepresented in TLR signaling pathway. This study shows for the first time the potential of aptamers to activate immune system after systemic application into the human blood. Thus, we highly recommend performing of these preclinical tests with potential aptamer-based therapeutics. To evaluate the influence of synthetic ssDNA oligonucleotides (SB_ODN, CpG_ODN) on the cells of circulating peripheral blood (n=3), the samples were divided into 7 groups, 0h_without ssDNA, 2h_without ssDNA, 2h_with SB_ODN, 2h_with CpG_ODN, 4h_without ssDNA, 4h_with SB_ODN, 4h_with CpG_ODN. Baseline value samples (0h_without ssDNA) were obtained after blood collection without rotating in the closed-loop model. Negative control samples (2h_without ssDNA and 4h_without ssDNA) did not include oligonucleotides but rotated in the closed-loop model.

ORGANISM(S): Homo sapiens

SUBMITTER: Meltem Avci-Adali 

PROVIDER: E-GEOD-46676 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress