Proteasome Inhibition Increases the Efficiency of Lentiviral Vector-Mediated Transduction of Trabecular Meshwork.

Brandt Lab // Kaufman Lab // Publications // Jan 01 2018

PubMed ID: 29340644

Author(s): Aktas Z, Rao H, Slauson SR, Gabelt BT, Larsen IV, Sheridan RTC, Herrnberger L, Tamm ER, Kaufman PL, Brandt CR. Proteasome inhibition increases the efficiency of lentiviral vector-mediated transduction of trabecular meshwork. Invest Ophthalmol Vis Sci. 2018 Jan 1;59(1):298-310. doi: 10.1167/iovs.17-22074. PMID 29340644

Journal: Investigative Ophthalmology & Visual Science, Volume 59, Issue 1, 01 2018

Purpose To determine if proteasome inhibition using MG132 increased the efficiency of FIV vector-mediated transduction in human trabecular meshwork (TM)-1 cells and monkey organ-cultured anterior segments (MOCAS).

Methods TM-1 cells were pretreated for 1 hour with 0.5% dimethyl sulfoxide (DMSO; vehicle control) or 5 to 50 μM MG132 and transduced with FIV.GFP (green fluorescent protein)- or FIV.mCherry-expressing vector at a multiplicity of transduction (MOT) of 20. At 24 hours, cells were fixed and stained with antibodies for GFP, and positive cells were counted, manually or by fluorescence-activated cell sorting (FACS). Cells transduced with FIV.GFP particles alone were used as controls. The effect of 20 μM MG132 treatment on high- and low-dose (2 × 107 and 0.8 × 107 transducing units [TU], respectively) FIV.GFP transduction with or without MG132 was also evaluated in MOCAS using fluorescence microscopy. Vector genome equivalents in cells and tissues were quantified by quantitative (q)PCR on DNA.

Results In the MG132 treatment groups, there was a significant dose-dependent increase in the percentage of transduced cells at all concentrations tested. Vector genome equivalents were also increased in TM-1 cells treated with MG132. Increased FIV.GFP expression in the TM was also observed in MOCAS treated with 20 μM MG132 and the high dose of vector. Vector genome equivalents were also significantly increased in the MOCAS tissues. Increased transduction was not seen with the low dose of virus.

Conclusions Proteasome inhibition increased the transduction efficiency of FIV particles in TM-1 cells and MOCAS and may be a useful adjunct for delivery of therapeutic genes to the TM by lentiviral vectors.