AB0063 High-efficiency transduction of mesenchymal stem cells by aav2/dj vector for their potential use in autoimmune diseases

Abstract

Background Mesenchymal stem cells (MSC), multipotential non-hematopoietic progenitors, can be isolated from various tissues and can modulate allogeneic immune cell responses. These properties make MSC as a promising potential treatment of autoimmune diseases.1 Our previous studies have found that bone marrow-derived (BM)-MSC from systemic lupus erythematosus (SLE) patients are defective structurally and functionally,2 treatment with modified and optimised MSC may bring a better effect on patients with autoimmune diseases. Most efforts have relied on adeno- and lentiviral vectors for delivering genes to MSC. Effective as these vectors may be, concerns regarding their immunogenicity and, in the case of lentivirus, the risk of insertional mutagenesis, have led to the pursuit of safer alternatives. Among these, adeno-associated virus (AAV) holds several advantages as a vector for human gene therapy. There are many serotypes of AAV available, and certain serotypes have been found to transduce specific cell types more efficiently than others. Objectives To determine the efficiency of different serotypes of AAV vectors for their ability to mediate transduction of different sources of MSC and assess whether AAV transduction affects MSC multipotentiality. Methods Serotypes 1, 2, 5, 6, 8, 9, PHP and DJ of AAV vectors were constructed in Viral Core, Boston Children’s Hospital. The enhanced green fluorescent protein (eGFP) gene under transcriptional control of a CAG promoter was cloned into the AAV vector backbone. MSC derived from umbilical cord (UC), BM and amniotic fluid (AF) were isolated and approximately 1 × 105 MSC were used for transductions with AAV vectors. eGFP expression was evaluated 3 days after transduction by fluorescence microscopy and flow cytometry. The capacity of MSC to differentiate in vitro was assessed. ![Abstract AB0063 – Figure 1][1] Abstract AB0063 – Figure 1 A: the transduction efficiencies of AAVs (MOI=5:1) in AF-MSC, BM-MSC and UC-MSC, B: the transduction efficiencies of AAV/DJ in UC-MSC with different MOI. Results Conclusions AAV2/DJ vector can be used as a highly efficient tool to modify MSC ex vivo for therapeutic transplantation for autoimmune diseases. References [1] Liang J, Wang D, Dominique F, Sun L. Mesenchymal stem cells for treating autoimmune diseases: The Chinese experience from lab to clinics. Curr Res Transl Med.2016;64(2):115–20. [2] Sun L, Akiyama K, Zhang H, et al. Mesenchymal stem cell transplantation reverses multiorgan dysfunction in systemic lupus erythematosus mice and humans. Stem Cells2009;27(6):1421–32. Disclosure of Interest None declared [1]: pending:yes