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Kammala, A. K.

Publications and source records attributed to Kammala, A. K..

4 recordsLinked to original sources

Exofection as a Therapeutic Modality: Restoring P-gp Activity via Trophoblast-Derived EV in Neuroinflammatory Disorders

BackgroundP-glycoprotein (P-gp/ABCB1) is a key efflux transporter that maintains barrier integrity by clearing xenobiotics and toxic metabolites. At the feto-maternal interface, trophoblast-derived extracellular vesicles (CTC-EVs) naturally and transiently transfer functional P-gp to maternal decidual cells, restoring lost and or reduced P-gp function (exofection) to sustain pregnancy homeostasis. A similar loss of P-gp at the blood brain barrier (BBB) contributes to impaired amyloid-{beta} (A{beta}) clearance and neuroinflammation in Alzheimers disease. We investigated whether CTC-EV-mediated exofection could restore P-gp function in human brain endothelial cells (hBECs) and enhance A{beta} clearance under inflammatory and neurodegenerative conditions. MethodsCTC-EVs were isolated and characterized by nanoparticle tracking analysis and western blotting for P-gp and EV markers. Transcriptomic profiling of CTC-EVs identified enrichment of transporter-related genes, including solute carriers and ABC transporters, along with inflammatory mediators. Network analysis revealed coordinated modules linking EV cargo to transporter regulation, endocytosis/trafficking pathways, and inflammatory remodeling processes converging on BBB efflux activity. hBECs were exposed to LPS (500 ng/mL, 48 h) with or without CTC-EVs. P-gp expression was assessed by immunofluorescence (mean fluorescence intensity, MFI) and western blotting, while functional efflux was measured using Calcein-AM assays. A{beta} oligomer transport was evaluated using a transwell hBEC model. In vivo, 3xTg-AD mice received intravenous CTC-EVs (1x10L/day for 5 days), followed by assessment of P-gp expression, A{beta} burden, and neuroinflammatory markers. Pharmacokinetic studies in P-gp knockout mice were conducted to confirm functional transporter recovery. ResultsLPS exposure significantly reduced P-gp expression in hBECs (41.3% decrease in MFI, p=0.0084), which was restored by CTC-EVs (46.7% increase vs. LPS, p=0.0121). Exofection increased P-gp by a 2.1-fold following EV treatment as determined by western blot. Functional assays demonstrated enhanced efflux, with a 38.5% reduction in intracellular Calcein fluorescence (p<0.001). Network-informed mechanisms supported coordinated regulation of transporter and trafficking pathways. CTC-EVs improved A{beta} transport across inflamed hBEC monolayers. In vivo, EV-treated 3xTg-AD mice exhibited increased P-gp expression in the frontal cortex (38.6%) and hippocampus (42.1%), reduced A{beta} plaque burden (27.9%), and decreased inflammatory markers (IL-1{beta} and TNF-, p<0.05). In P-gp knockout mice, EVs reduced brain drug accumulation by 22.4% (p=0.032), confirming restoration of transporter function. ConclusionCTC derived EVs are natural carriers of functional transporter proteins and restore efflux capacity in compromised endothelial barriers. Integration of transcriptomic and network analyses highlights coordinated regulation of transporter, trafficking, and inflammatory pathways underlying exofection. This reproductive biology inspired strategy offers a promising therapeutic approach for enhancing A{beta} clearance and mitigating neuroinflammation in Alzheimers disease.

pharmacology and toxicology↗

From Stress to Survival: Trophoblast-Derived Extracellular Vesicle Proteome Captures Aspirin-Driven Cellular Reprogramming in a Preeclampsia Model.

BackgroundLow-dose aspirin (LDA) reduces preeclampsia (PE) risk by up to 40%, yet its molecular effects on chorion trophoblast cells (CTCs) a fetal membrane lineage at the feto-maternal interface remain obscure. CTCs form a structural and immunoregulatory barrier whose dysfunction drives inflammation-associated membrane pathology in PE. Extracellular vesicles (EVs) released by CTCs may encode cellular stress and adaptation states, offering a molecular window into aspirins timing-dependent effects on PE risk modification. MethodsHuman CTCs were challenged with cigarette smoke extract (CSE) to model oxidative stress-driven PE pathology. Two paradigms were tested: (1) prophylactic aspirin (4 and 40 {micro}g/ml) before and/or flanking CSE, and (2) therapeutic aspirin after CSE challenge. EVs were isolated via ultracentrifugation and size exclusion chromatography, characterized by nanoparticle tracking and immunoblotting, and profiled by quantitative mass spectrometry. Network pathway analysis and machine-learning biomarker selection defined EV-encoded molecular states. ResultsCTC-derived EVs from CSE-exposed cells carried a PE-like proteomic signature marked by suppressed VEGF/ECM remodeling, activated TNF-p53 apoptotic signaling, and heightened inflammation. Prophylactic low-dose aspirin shifted EV cargo toward preserved angiogenic capacity (VEGFA, COL1A1, MMP14) with attenuated apoptotic and NF-{kappa}B signatures. High-dose aspirin produced broad transcriptional suppression without vascular benefit in EVs. Therapeutic aspirin partially rescued injury-associated EV cargo but failed to restore angiogenic signatures. Machine-learning analysis of EV proteomes identified a prophylactic biomarker panel anchored by HSPA8, SERPINF2, COL4A1, and PLOD1, linked to angiogenic recovery and redox balance. ConclusionsCTC-derived EV proteomic signatures capture dose-and timing-dependent aspirin effects, positioning the chorion as a pharmacological "secondary responder" favoring cellular resilience over classical anti-inflammatory suppression. EV-based molecular profiling might offer a framework for stratifying aspirin responders from non-responders toward personalized PE prevention.

cell biology↗

Prenatal Exposure to Bacterial Extracellular Vesicles Influences Fetal Gut Immunity and Immune Programming

BackgroundThe fetal immune system undergoes pivotal development during gestation, preparing for postnatal antigenic challenges. Bacterial extracellular vesicles (bEVs), bioactive particles shed by bacteria, are emerging as modulators of host immunity. However, their role in shaping fetal intestinal immune development remains largely unexplored. ObjectivesThis study aimed to investigate the effects of bEV exposure on lymphoid and myeloid populations in the fetal murine gut, focusing on their role in priming intestinal immunity, promoting differentiation, and modulating immune cell phenotypes in both normal and germ-free (GF) environments. Materials and MethodsWe used a murine model to evaluate the immune-modulating effects of bEVs during fetal development. bEVs were isolated from bacterial cultures and introduced into the amniotic sac of embryonic day 15.5 (E15.5) fetuses through intra-amniotic injection. Fetal and neonatal mice were either raised under conventional conditions (normal environment, NE) or in germ-free (GF) environments to assess microbiota-dependent effects. Immune profiling of fetal (E17) and postnatal (4 weeks) gut tissues was performed using high-dimensional mass cytometry (CyTOF) in both conventionally housed and germ-free (GF) mice. Clustering and differential expression analyses identified lymphoid and myeloid subpopulations, including progenitors, antigen-presenting cells, and intestinal stem cells (ISCs). secondary immune challenge (LPS or TSST-1) was conducted in postnatal bEV-primed mice to assess immune memory responses. ResultsbEV exposure significantly increased the prevalence of CD45- CD24+ CD44+ ISCs, promoting intestinal renewal and defense via differentiation into Paneth and tuft cells. These ISCs exhibited potential antigen-presenting capabilities through MHC expression. CD45+ lymphoid progenitors were upregulated, highlighting their role in early differentiation pathways. Myeloid progenitors, particularly monocyte-dendritic progenitor subsets, showed a bias toward antigen-presenting phenotypes.Germ-free models revealed heightened sensitivity to bEVs, with pronounced activation of progenitors and a reduction in exhaustion markers. Interestingly, macrophage and neutrophil populations displayed dose-dependent modulation, with low bEV concentrations promoting their expansion and higher doses leading to reduced incidence. Our findings suggest that bEVs act as immune priming agents in the fetal gut, promoting progenitor expansion and differentiation while preparing the intestine for postnatal challenges. Differences in responses between NE and GF models emphasize the importance of environmental influences, including microbiota, on bEV-mediated immune modulation. ConclusionbEVs play a pivotal role in shaping fetal intestinal immunity by priming lymphoid and myeloid progenitors and enhancing ISC function. These results open potential avenues for leveraging bEVs in immunomodulation and vaccine strategies. Future studies should explore the functional responses of bEV-primed cells and their translational relevance in humans.

developmental biology↗

P-glycoprotein exofection between fetal and maternal cells as a mechanism of intercellular material transfer at the feto maternal interface

Cells can recover lost protein functions through a process we term exofection, in which extracellular vesicles deliver functional molecular cargo to recipient cells and transiently reprogram their activity. Here we show that exosomes derived from fetal chorion trophoblast cells (CTCs) restore P-glycoprotein (P-gp) efflux transporter function in inflammation-impaired maternal decidual cells (DECs) at the feto-maternal interface. CTCs maintain high P-gp expression under inflammatory stress, whereas DECs exhibit marked downregulation of transporter genes and proteins. Proteomic analysis revealed that CTC-derived exosomes package P-gp as a stable cargo that enters DECs through clathrin- and heparan sulfate-dependent uptake pathways. Delivery of CTC exosomes reinstated P-gp abundance and efflux capacity in LPS-stimulated or P-gp-deficient DECs, as shown by calcein efflux and immunofluorescence assays. In pregnant P-gp knockout mice, exosome treatment restored systemic clearance of the P-gp substrate tacrolimus and improved pharmacokinetic parameters. These findings establish exofection as a naturally occurring mechanism of transporter rescue at the feto-maternal interface, where fetal exosomes compensate for inflammation-induced maternal loss of efflux capacity. By restoring P-gp-mediated barrier function, exofection provides a protective strategy that limits the accumulation of xenobiotics and cytokines in maternal tissues and safeguards the fetus. This work reveals a previously unrecognized form of intercellular communication with broad implications for fetal protection, placental biology, cellular engineering, and the delivery of therapeutic proteins. One Sentence SummaryExofection is identified as a novel mechanism of transient cellular engineering via exosome-mediated functional protein delivery between cells.

developmental biology↗