Increased Neurite Orientation-Dispersion and Density in the TgCRND8 Mouse Model of Amyloidosis: Inverse Relation with Functional Connectome Clustering and Modulation by Interleukin-6

Luis M. Colon-Perez; Kristen R. Ibanez; Mallory Suarez; Kristin Torroella; Kelly Acuna; Edward Ofori; Yona Levites; David E. Vaillancourt; Todd E. Golde; Paramita Chakrabarty; Marcelo Febo

The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. . https://doi.org/10.1101/562348 doi: bioRxiv preprint Recombinant adeno-associated virus subtype 2/1 (rAAV2/1) for intracerebroventricular (ICV) injections expressing murine IL6 (m-IL6) or enhanced green fluorescent protein (EGFP) under the control of the cytomegalovirus enhancer/chicken β actin promoter were generated as described previously . Briefly, rAAV vectors expressing IL6 under the control of the cytomegalovirus enhancer/chicken beta actin (CBA) promoter, a WPRE, and the bovine growth hormone polyA were generated by plasmid transfection with helper plasmids in HEK293T cells. Forty-eight hours after transfection, cells were harvested and lysed in the presence of 0.5% Sodium Deoxycholate and 50U/ml Benzonase (Sigma) by freeze thawing and the virus isolated using a discontinuous Iodixanol gradient and affinity purified on a HiTrap HQ column (Amersham). The genomic titer of each virus was determined by quantitative polymerase chain reaction (qPCR). TgCRND8 and nTg mice were injected with 2 μl of rAAV (~2E10 viral genomes) into cerebral ventricles using a 10 µl Hamilton syringe with a 30 g needle on day P0 as described before Chakrabarty et al., 2015) . Animals were euthanized within 1-2 days of imaging.