Dimerization of an aptamer generated from Ligand-guided selection (LIGS) yields a high affinity scaffold against B-cells

Publication date: Available online 17 October 2018Source: Biochimica et Biophysica Acta (BBA) - General SubjectsAuthor(s): Sana Batool, Kimon V. Argyropoulos, Roksana Azad, Precious Okeoma, Hasan Zumrut, Sanam Bhandari, Rigzin Dekhang, Prabodhika R. MallikaratchyAbstractNucleic Acid Aptamers (NAAs) are a class of synthetic DNA or RNA molecules that bind specifically to their target. We recently introduced an aptamer termed R1.2 against membrane Immunoglobulin M (mIgM) expressing B-cell neoplasms using Ligand Guided Selection (LIGS). While LIGS-generated aptamers are highly specific, their lower affinity prevents aptamers from being used for translational applications. Highly specific aptamers with higher affinity can increase targetability, boosting the application of aptamers as diagnostic and therapeutic molecules. Herein, we report that dimerization of R1.2, an aptamer generated from LIGS, leads to high affinity variants without compromising the specificity. Three dimeric aptamer analogues with variable linker lengths were designed to evaluate the effect of linker length in affinity. The optimized dimeric R1.2 against cultured B-cell neoplasms, four donor B-cell samples and mIgM-positive Waldenström's Macroglobulinemia (WM) showed specificity. Furthermore, confocal imaging of dimeric aptamer and anti-IgM antibody in purified B-cells suggests co-localization. Binding assays against IgM knockout Burkitt's Lymphoma cells utilizing CRISPR/Cas9 further validated specificity of...
Source: Biochimica et Biophysica Acta (BBA) General Subjects - Category: Biochemistry Source Type: research