Biology subjects

Gendelman, H.

Publications and source records attributed to Gendelman, H..

4 recordsLinked to original sources

bioRxiv2026

Accelerated amyloid neurodegeneration in HIV-1-infected APP-KI Alzheimer's disease mice

STRUCTURED ABSTRACTO_ST_ABSINTRODUCTIONC_ST_ABSA higher incidence of dementia, including Alzheimer s-like pathology, is observed in aged people living with HIV-1. However, mechanisms linking HIV-1 to Alzheimers disease (AD) pathology remain unclear, due to the lack of animal models that allow for concurrent study. METHODSWe created a novel APP knock-in (KI) AD mouse, NOG/APPKM670,671NL/IL-34 (hNAIL) that permits study of progressive brain HIV-1 replication. The mice harbor human microglia-like cells. Four-month-old CD34+ human cell reconstituted mice infected with the HIV-1ADA strain facilitated studies of HIV-1 replication on AD pathologies. RESULTSHIV-1 replication increased A{beta} levels and reduced synaptic and neuronal integrity. Spatial transcriptomics demonstrated distinct A{beta} and HIV-1 transcriptional patterns, whereas dual diseased combinations amplified AD pathology. Neurons showed highest transcriptional change, with genes linked to neuroinflammation, protein trafficking, and synaptic dysfunction. DISCUSSIONThe hNAIL mice enable interrogation of HIV-AD comorbidities, with a future potential for the development of novel therapeutic interventions.

neuroscience↗

bioRxiv2021

Defining the Immune Responses for SARS-CoV-2-Human Macrophage Interactions

Host innate immune response follows severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and it is the driver of the acute respiratory distress syndrome (ARDS) amongst other inflammatory end-organ morbidities. Such life-threatening coronavirus disease 2019 (COVID-19) is heralded by virus-induced activation of mononuclear phagocytes (MPs; monocytes, macrophages, and dendritic cells). MPs play substantial roles in aberrant immune secretory activities affecting profound systemic inflammation and end organ malfunctions. All follow an abortive viral infection. To elucidate SARS-CoV-2-MP interactions we investigated transcriptomic and proteomic profiles of human monocyte-derived macrophages. While expression of the SARS-CoV-2 receptor, the angiotensin-converting enzyme 2, paralleled monocyte-macrophage differentiation it failed to affect productive viral infection. In contrast, simple macrophage viral exposure led to robust pro-inflammatory cytokine and chemokine expression but attenuated type I interferon (IFN) activity. Both paralleled dysregulation of innate immune signaling pathways specifically those linked to IFN. We conclude that the SARS-CoV-2-infected host mounts a robust innate immune response characterized by a pro-inflammatory storm heralding consequent end-organ tissue damage.

immunology↗

bioRxiv2021

Antiretroviral Theranostics Based on Intrinsic CEST Contrasts

Human immunodeficiency virus type-1 (HIV-1) antiretroviral drug (ARV) theranostics facilitates biodistribution and efficacy of therapies designed to target viral reservoirs. To this end, we have now deployed intrinsic drug chemical exchange saturation transfer (CEST) contrast to detect ARV distribution within the central nervous system (CNS). MethodsCEST effects for lamivudine (3TC) and emtricitabine (FTC) were measured by asymmetric magnetization transfer ratio analyses in solutions. CEST magnetic resonance imaging (MRI) was performed on 3TC-treated mice with analysis made by Lorentzian fitting. ResultsCEST effects of 3TC and FTC hydroxyl and amino protons linearly correlated to drug concentrations. 3TC was successfully detected in brain sub-regions by MRI. The imaging results were validated by measurements of CNS drug concentrations. ConclusionCEST contrasts can be used to detect ARVs using MRI. Such detection can be used to assess spatial-temporal drug biodistribution. This is most notable within the CNS where drug biodistribution may be more limited with the final goal of better understanding ARV-associated efficacy and potential toxicity.

bioengineering↗

bioRxiv2020

Elucidating the pathogenic mechanisms of AD brain-derived tau-containing extracellular vesicles: Highly transmissible and preferential propagation to GABAergic neurons

Extracellular vesicles (EVs) propagate tau pathology for Alzheimers disease (AD). How EV transmission influences AD are, nonetheless, poorly understood. To these ends, the physicochemical and molecular structure-function relationships of human brain-derived EVs, from AD and prodromal AD (pAD), were compared to non-demented controls (CTRL). AD EVs were shown to be significantly enriched in epitope-specific tau oligomers versus pAD or CTRL EVs assayed by dot-blot and atomic force microscopy tests. AD EVs were efficiently internalized by murine cortical neurons and transferred tau with higher aggregation potency than pAD and CTRL EVs. Strikingly, inoculation of tau-containing AD EVs into the outer molecular layer of the dentate gyrus induced tau propagation throughout the hippocampus. This was seen in 22 months-old C57BL/6 mice at 4.5 months post-injection by semiquantitative brain-wide immunohistochemistry tests with multiple anti-phospho-tau (p-tau) antibodies. Inoculation of the equal amount of tau from CTRL EVs or as oligomer or fibril-enriched fraction from the same AD donor showed little propagation. AD EVs induced tau accumulation in the hippocampus as oligomers or sarkosyl-insoluble proteins. Unexpectedly, p-tau cells were mostly GAD67+ GABAergic neurons and to a lesser extent, GluR2/3+ excitatory mossy cells, showing preferential EV-mediated GABAergic neuronal tau propagation. Whole-cell patch clamp recording of Cornu Ammonis (CA1) pyramidal cells showed significant reduction in the amplitude of spontaneous inhibitory post-synaptic currents. This was accompanied by reductions in c-fos+ GAD67+GABAergic neurons and GAD67+ GABAergic neuronal puncta surrounding pyramidal neurons in the CA1 region confirming reduced interneuronal projections. Our study posits a novel tau-associated pathological mechanism for brain-derived EVs.

neuroscience↗