Biology subjects

Markoutsa, E.

Publications and source records attributed to Markoutsa, E..

4 recordsLinked to original sources

bioRxiv2026

Dendrimer Delivered shRNA Targeting the CCL20-CCR6 Axis Suppresses Complement-Mediated Microglial Synaptic Pruning and Ameliorates Chronic Neuroinflammation After Repetitive Traumatic Brain Injury

Repetitive traumatic brain injury (rTBI) induces persistent microglial activation and chronic neuroinflammation, yet the upstream signals driving long-term synaptic injury remain unclear. In this study, we identify the CCL20-CCR6 chemokine axis as a critical regulator of sustained microglial activation and complement-dependent synaptic loss after rTBI. Proteomic profiling at 30 days post-injury (dpi) showed broad normalization of complement-linked inflammatory and synaptic pathways in the cortex and hippocampus, underscoring a mechanistic link between chemokine signaling, microglial activation, and synaptic vulnerability. To therapeutically target this axis, we developed a dendrimer-based shRNA platform (shCombo-DPX) that simultaneously silences CCL20 and CCR6. Intranasal and intravenous delivery in rTBI mice effectively reduced CCL20-CCR6 expression, attenuated chronic microgliosis and astrogliosis, and suppressed complement activation. Treatment limited microglial synaptic engulfment, preserved synaptic proteins, restored BDNF levels, and improved motor, anxiety-related, and cognitive outcomes. In microglia-neuron coculture systems, CCL20 silencing reduced LPS-induced complement signaling and prevented synaptic loss, neuronal apoptosis, and BDNF depletion. Conversely, exposure to recombinant CCL20 induced dendritic degeneration, caspase-3 activation, microglial reactivity, complement dysregulation, and synaptic injury both in vitro and in vivo. Collectively, these findings establish CCL20-CCR6 as a key upstream driver of chronic complement-mediated synaptic degeneration after rTBI and support dendrimer-delivered shRNA therapy as a targeted strategy to mitigate long-term neurodegeneration.

neuroscience↗

bioRxiv2026

CCL20-CCR6 Signaling as a Prognostic Biomarker and Therapeutic Target in Temozolomide-Resistant Glioblastoma

Glioblastoma remains highly lethal, with median survival of ~15 months. Resistance to temozolomide is ubiquitous, yet its mechanisms are incompletely understood. Here, we identify the CCL20-CCR6 chemokine axis as a stress-responsive survival pathway limiting therapeutic efficacy. Targeting CCL20-CCR6 in combination with temozolomide and cannabidiol was evaluated using clinical datasets, GBM cell lines, tumor organoids, and a syngeneic CT-2A mouse model integrating proteomic and lipidomic profiling. Low CCL20 expression was associated with improved survival, supporting its prognostic relevance. Across models, TMZ alone or with CBD induced CCL20 expression while exerting limited antitumor activity. Targeted disruption of CCL20-CCR6 signaling using dendrimer-delivered shRNA enhanced therapeutic response in murine models and GBM organoids. Multi-omic analyses revealed that CCL20 inhibition reprograms the tumor microenvironment and induces mitochondrial dysfunction, resulting in elevated reactive oxygen species (ROS) and tumor cell death. This effect was accompanied by accumulation of 17-hydroxydocosahexaenoic acid and activation of oxidative stress-associated cytotoxic pathways. Functional assays confirmed that CCL20 blockade selectively amplifies mitochondrial ROS beyond levels induced by TMZ alone potentiating TMZ efficacy by promoting mitochondrial oxidative stress. Targeting this axis represents a promising strategy to overcome chemoresistance and positions CCL20 as both a prognostic biomarker and a therapeutic vulnerability in GBM.

cancer biology↗

bioRxiv2026

Glomerular-Targeted Delivery of Low-Dose Prednisolone Attenuates Established Lupus Nephritis in MRL/lpr Mice.

BackgroundLupus nephritis remains a major cause of chronic kidney disease and kidney failure in systemic lupus erythematosus. Glucocorticoids are central to treatment but are limited by systemic toxicity. We evaluated whether a previously characterized collagen IV 3-targeted liposomal nanoparticle formulation carrying low-dose prednisolone could attenuate established lupus nephritis in MRL/lpr mice. MethodsFemale MRL/lpr mice with disease present at treatment initiation and C57BL/6J control mice received saline or collagen IV 3-targeted prednisolone-loaded nanoparticles (Col4-3-Pred-NPs). Renal outcomes were assessed by longitudinal proteinuria, glomerular filtration rate (GFR), survival, kidney histopathology, renal IgG and C3d deposition, dUTP/TUNEL-associated injury staining, and renal cytokine/chemokine profiling. Body weight, food and water intake, and blood glucose were monitored as measures of general condition and preliminary tolerability. ResultsCol4-3-Pred-NPs improved survival in MRL/lpr mice, reduced cumulative proteinuria burden, and attenuated terminal GFR decline compared with saline-treated MRL/lpr controls. Treatment reduced glomerular and tubulointerstitial injury, lowered composite EGTI histopathology scores, decreased terminal kidney enlargement, reduced glomerular IgG deposition and renal dUTP-positive injury signals, and reduced renal signals for IL-28A/B, IL-7, PD-ECGF, IL-11, CCL6/C10, and IL-15. C3d deposition was not significantly altered. Nanoparticle treatment was not associated with sustained treatment-related increases in blood glucose or body-weight loss during the measured study period. ConclusionsCollagen IV 3-targeted liposomal delivery of low-dose prednisolone attenuated established lupus nephritis in MRL/lpr mice and improved renal structural, functional, inflammatory, and survival outcomes. These findings support further evaluation of glomerulus-targeted nanotherapy as a potential strategy to improve the precision and therapeutic index of glucocorticoid treatment in lupus nephritis.

physiology↗

bioRxiv2026

Glomerulus-Targeted Nanotherapy via Collagen IV-α3 Binding Enhances Renal Immunoregulation in Lupus Nephritis

Lupus nephritis requires long-term immunosuppressive therapy, which is often associated with severe systemic side effects. Therefore, new therapeutic strategies that maintain high efficacy while minimizing adverse effects is essential. Although nanomedicine has advanced systemic and kidney-targeted drug delivery, a reliable method for glomerulus-specific delivery is lacking. Collagen IV (Col4)-alpha 3, located in the glomerular basement membrane (GBM) at the blood-tissue interface through fenestrated capillary endothelium, represents an ideal target for glomeruli delivery. Herein, we developed a novel liposomal nanoparticle conjugated with a Col4-alpha 3 binding peptide (Col4-3-NPs) for selective glomerular targeting. Prednisolone-loaded Col4-3-NPs were administered to lupus-prone mice twice weekly for 8 weeks. Kidney injury and function were evaluated biweekly, and renal immune cell populations were analyzed by flow cytometry at study completion. The results show that rhodamine-labeled NPs predominantly accumulate in kidney glomeruli 48 hours after intravenous injection. The Col4-NP system demonstrated stable and prolonged release of the encapsulated drug for over 48 hours. Lupus-prone mice treated with prednisolone-loaded Col4-NPs showed significantly improved renal function and histology, including a 30% increase in glomerular filtration rate (GFR), a 56% reduction in proteinuria, and decreased IgG deposition and fibrosis. Notably, treatment also enhanced renal regulatory T cell (Treg) populations. These findings suggest that glomerulus-targeted Col4-3-NPs hold significant translational promise. This platform may offer an effective, site-specific treatment for lupus nephritis while minimizing systemic side effects and could be adapted for other glomerular diseases requiring targeted therapy.

physiology↗