Biology subjects

Discenza, C. B.

Publications and source records attributed to Discenza, C. B..

3 recordsLinked to original sources

bioRxiv2024

Engineering anti-amyloid antibodies with transferrin receptor targeting improves safety and brain biodistribution

Although the first generation of immunotherapies for Alzheimers disease (AD) are now clinically approved, amyloid-related imaging abnormalities (ARIA) remain a major safety problem for this class of drugs. Here, we report an antibody transport vehicle (ATV) targeting the transferrin receptor (TfR) for brain delivery of amyloid beta (A{beta}) antibodies that significantly reduced ARIA-like lesions and improved plaque target engagement in a mouse model of amyloid deposition. Asymmetrical Fc mutations (ATVcisLALA) allowed the molecule to selectively retain effector function only when bound to A{beta} while mitigating TfR-related hematology liabilities. Mice treated with ATVcisLALA:A{beta} exhibited broad brain parenchymal antibody distribution; in contrast, anti-A{beta} IgG was highly enriched at arterial perivascular spaces where vascular A{beta} localizes and likely plays a role in induction of ARIA. Importantly, ATVcisLALA: A{beta} almost completely eliminated ARIA-like lesions and vascular inflammation associated with anti-A{beta} treatment. Taken together, ATVcisLALA has the potential to significantly improve both safety and efficacy of A{beta} immunotherapy through enhanced biodistribution mediated by transport across the blood-brain barrier.

neuroscience↗

bioRxiv2024

Fc-engineered large molecules targeting blood-brain barrier transferrin receptor and CD98hc have distinct central nervous system and peripheral biodistribution compared to standard antibodies

The blood-brain barrier (BBB) poses a significant challenge drug delivery to the brain. BBB-crossing molecules are emerging as a new class of therapeutics with significant potential for central nervous system (CNS) indications. In particular, transferrin receptor (TfR)- and CD98 heavy chain (CD98hc)-targeting molecules have been demonstrated to cross the BBB for enhanced brain delivery. Previously, we reported TfR and CD98hc antibody transport vehicles (ATVTfR and ATVCD98hc) that utilize these BBB receptors to improve CNS drug delivery1,2. Here, we provide a comprehensive and unbiased biodistribution characterization of ATVTfR and ATVCD98hc compared to a standard IgG at a multiscale level, ranging from whole-body to brain region- and cell type-targeting specificity. Mouse whole-body tissue clearing revealed distinct organ localization for each molecule. In the CNS, ATVTfR and ATVCD98hc not only achieves enhanced brain delivery but importantly, much broader parenchymal distribution in contrast to the severely limited distribution observed with a standard antibody that was not able to be improved even at very high dose levels. Using cell sorting and single-cell RNA sequencing of mouse brain, we revealed that standard IgG predominantly localizes to perivascular and leptomeningeal cells and reaches the CNS by entering the CSF, rather than crossing the BBB. In contrast, ATVTfR and ATVCD98hc enables broad parenchymal cell-specific distribution via transcytosis through brain endothelial cells (BECs) along the neurovasculature. Finally, we extended the translational relevance of our findings by revealing enhanced and broad brain and spinal cord biodistribution of ATVTfR compared to standard IgG in cynomolgus monkey. Taken together, this multiscale analysis reveals in-depth biodistribution differences between ATVTfR, ATVCD98hc, and standard IgG. These results may better inform platform selection for specific therapeutic targets of interest, optimally matching platforms to desired CNS target engagement, peripheral organ exposures, and predict or potentially reduce off-target effects.

neuroscience↗

bioRxiv2023

Targeting Transferrin Receptor to Transport Antisense Oligonucleotides Across the Blood-Brain Barrier

Antisense oligonucleotides (ASO) are promising therapies for neurological disorders, though they are unable to cross the blood-brain barrier (BBB) and must be delivered directly to the central nervous system (CNS). Here, we use a human transferrin receptor (TfR)-binding molecule to transport ASO across the BBB in mice and non-human primates, termed oligonucleotide transport vehicle (OTV). Systemically delivered OTV drives significant, cumulative, and sustained knockdown of the ASO target across multiple CNS regions and all major cell types. Further, systemic OTV delivery enables more uniform ASO biodistribution and knockdown compared to two other clinically relevant ASO delivery routes: a standard, high affinity TfR antibody, or direct ASO delivery to the CSF. Together, our data support systemically delivered OTV as a potential therapeutic platform for neurological disorders. One-Sentence SummarySystemically dosed OTV delivered via TfR1 targeting shows widespread and cumulative target knockdown in the mouse and NHP CNS.

neuroscience↗