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Camargo, C. M.

Publications and source records attributed to Camargo, C. M..

2 recordsLinked to original sources
bioRxiv2026

BAG2 Condensates Couple Proteostasis to CD8+T Cell Surveillance

Protein aggregation, impaired degradation, and immune activation are central hallmarks of neurodegenerative diseases, yet how these processes are coordinated remains unclear. Here, we identify Immune-Protein Degradation Bodies (I-PDBs), a previously unrecognized class of BAG2-driven, phase-separated organelles that integrate protein quality control with adaptive immunity. IFN{gamma} induce I-PDB formation at the endoplasmic reticulum (ER), where they concentrate immunoproteasome components, MHC-I peptide-loading machinery, and ER-associated chaperones. I-PDBs redirect proteostatic cargo from centrosomal aggregation pathways to spatially restricted degradation sites optimized for antigenic peptide generation, coupling selective substrate clearance to CD8 T cell engagement. Using a cellular model of aggregation-prone tau, we show that I-PDBs capture pathological tau fibrils at ER-microtubule interfaces and process them into potentially antigenic peptides, thus reducing the load of aggregation-prone tau peptides. We term this mechanism the Proteostasis-Associated Immune Relay (PAIR), establishing I-PDBs as critical hubs linking proteostasis to immune surveillance with broad implications for disease. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/719751v1_ufig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@16fa503org.highwire.dtl.DTLVardef@ba7607org.highwire.dtl.DTLVardef@19ae5bdorg.highwire.dtl.DTLVardef@60fdf7_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIIFN{gamma} drives BAG2-dependent Immune-Protein Degradation Bodies (I-PDBs) C_LIO_LII-PDBs assemble at the endoplasmic reticulum and are enriched in immunoproteasome and MHC-I machinery C_LIO_LII-PDBs shunt misfolded proteins, including pathological tau, away from aggresomes C_LIO_LII-PDBs couple proteostasis to antigen presentation, enhancing CD8 T cell recognition C_LIO_LIThe Proteostasis-Associated Immune Relay (PAIR) defines a pathway linking proteostasis to adaptive immunity C_LI

cell biology↗
bioRxiv2026

Neuronal Population Effects of Ketamine on Human Brain Organoids

Ketamines rapid neuropsychiatric actions emerge from interactions that span receptors, cells, and circuits, but their net effects on human neuronal population dynamics remain incompletely defined. Here we combine human dorsal forebrain organoids with high-density microelectrode arrays (MEAs) to quantify ketamines effects from spikes to networks. In 6-month-old organoids, acute ketamine (20{square}g/mL) abolished population bursting while neuronal firing continued mostly unchanged. Spike sorting revealed that mean firing rates declined but not silenced after ketamine Reductions were concentrated within a subset of burst-driver units previously defined as "backbone". Functional connectivity, estimated with the spike time tiling coefficient (STTC), decreased globally after ketamine. Backbone units displayed elevated connectivity at baseline but were functionally disconnected by ketamine. Graph construction from STTC uncovered widespread network reconfiguration, characterized by redistribution of edges from backbone to non-backbone units leading to loss of hubs and less-interconnected communities. Re-exposure after chronic ketamine treatment no longer silenced population bursting, indicating tolerance. Together, these results show that ketamine acutely silences human organoid networks by disconnecting backbone units, while chronic exposure induces tolerance to re-silencing while reducing the number of backbone units and leaving the network less active and less connected. The organoid-MEA platform provides a scalable, human-relevant system for dissecting circuit-level drug effects.

neuroscience↗