Search Results (57)

Background: Lipedema is a progressive adipofascial disorder marked by painful nodular fat deposition that is often mistaken for obesity. While tumescent liposuction reduces limb volume with relative lymphatic safety, persistent large, painful lobules frequently remain, and excisional strategies risk iatrogenic lymphatic injury. We evaluated the application of intraoperative indocyanine green (ICG) lymphography to identify and preserve lymphatic channels during debulking surgery for symptomatic lipedema. Methods: We conducted a single-center case series (University of Pittsburgh Medical Center, July 2023–December 2024) of adults with lipedema refractory to conservative therapy who underwent a selective dermato-lipectomy (lobule/skin excision) with or without tumescent liposuction. Patients with clinical lymphedema or dermal backflow in ICG were excluded. Near-infrared ICG (SPY-PHI) was used for pre-incision mapping and real-time intraoperative guidance; lymphatic trajectories were marked and spared during lobule excision. Primary measures included dermal backflow patterns and lymph node transit time; secondary outcomes were complications and symptom burden (Lymphedema Life Impact Scale, LLIS) through ≥24 months. Results: Eight patients (five female/three male; mean age 49.5 ± 14.4 years; median BMI 52.65 kg/m²) underwent ICG-guided surgery. Preoperatively, linear lymphatic patterns were visualized up to the knee in all patients, but dermal backflow patterns could not be visualized in 83% from the level of the knee to the groin. Still, 67% demonstrated inguinal nodal uptake (mean transit 24 min), suggesting preserved lymphatic transport. All cases achieved intraoperative confirmation of intact lymphatic flow after debulking. The mean liposuction aspirate was 925 ± 250 mL per lower extremity; the mean excision mass was 2209 ± 757 g per lower extremity. Complications included two superficial cellulitis events (25%) and one wound dehiscence (12.5%); no hematomas or skin necrosis occurred. No patient developed clinical or imaging evidence of iatrogenic lymphedema during follow-up. Conclusions: Intraoperative ICG lymphography is a practical adjunct for lymphatic-sparing debulking of symptomatic lipedema, enabling real-time identification and preservation of superficial collectors while addressing focal lobules. This hybrid approach—targeted tumescent liposuction followed by ICG-guided superficial dermato-lipectomy—was associated with meaningful symptom improvement and a low morbidity in this early series. Full article

Dietary fat absorption is a complex, multi-step process involving digestion, enterocyte uptake, intracellular trafficking, re-esterification, and transport via lipoproteins into circulation. Because dietary fat absorption plays a central role in lipid homeostasis, metabolic syndrome, and fat malabsorption disorders, its study has a broad biomedical significance. However, experimental investigation of this process is technically challenging due to the short lifespan of enterocytes, the dual lymphatic and portal transport routes, and the need to trace the metabolic fate of absorbed lipids. This review summarizes and critically evaluates the major experimental systems used to study dietary fat absorption, highlighting their respective strengths, limitations, and utility. A guide for selecting the most appropriate model to study specific stages of dietary fat absorption is also presented. Ultimately, because each model carries inherent methodological constraints, integrative experimental strategies that combine complementary will be necessary to link mechanistic insights with physiological relevance. Full article

Immune checkpoint inhibitors (ICIs) have revolutionized cancer immunotherapy by enhancing T-cell-mediated anti-tumor responses in solid malignancies. However, their efficacy is often limited by tumor-specific factors, T-cell dysfunction in cold tumors, or in the presence of lymph node metastasis (LNM). Moreover, clinical trials indicate no significant survival advantage of sentinel lymph node biopsy (SLNB) over no lymph node surgery in early-stage cancers, highlighting the need for novel combinatorial approaches to improve treatment outcomes. Tumor electrochemotherapy (ECT) can overcome immunosuppressive barriers in the tumor microenvironment by applying high electric fields that create transient micropores in cell membranes. This allows the enhanced uptake of chemotherapeutic drugs, resulting in increased cytotoxicity and the release of damage-associated molecular patterns (DAMPs). This triggers immunogenic cell death (ICD), a process that signals immune cells to attack cancer and promotes tumor regression. Considering advancements in lymphatic-targeted therapies and the immunostimulatory potential of uninvolved tumor-draining lymph nodes (TDLNs), TDLN-targeted ECT may act as an in situ cancer vaccination, activating immune cells within TDLNs through the release of DAMPs and serving as a hub to orchestrate systemic anti-tumor immunity. In patients with negative preoperative lymph node assessments, this approach may preserve lymph node integrity and lymphatic drainage while eradicating tumor cell colonies. When applied as neoadjuvant therapy before any TDLN treatment, TDLN-targeted ECT may leverage higher tumor-associated antigen loads, foster persistent immune memory, and reduce the risk of post-operative immune evasion. Full article

Oleosomes are submicron oil bodies of a triacylglycerol core enveloped by a phospholipid monolayer and embedded proteins, forming a naturally assembled nanocarrier with exceptional oxidative resilience, interfacial stability, and biocompatibility. Their unique architecture supports solvent-free extraction, self-emulsification, and near-complete encapsulation of highly lipophilic compounds (log P > 4), including curcumin and cannabidiol, with reported efficiencies exceeding 95%. These plant-derived droplets enhance oral bioavailability through lymphatic uptake and enable targeted delivery strategies such as magnetically guided chemotherapy, which has reduced tumor burden by approximately 70% in vivo. The review critically examines recent advances in oleosome research, spanning botanical sourcing, green extraction technologies, interfacial engineering, xenobiotic encapsulation, pharmacokinetics, and therapeutic applications across oncology, dermatology, metabolic disease, and regenerative medicine. Comparative analyses demonstrate that oleosomes rival or surpass synthetic lipid nanocarriers in encapsulation efficiency, oxidative stability, and cost efficiency while offering a sustainable, clean-label alternative. Remaining challenges, including low loading of hydrophilic drugs, allergenicity, and regulatory standardization, are addressed through emerging strategies such as hybrid oleosome–liposome systems, recombinant oleosin engineering, and stimulus-responsive coatings. These advances position oleosomes as a versatile and scalable platform with significant potential for food, cosmetic, and pharmaceutical applications. Full article

Background/Objectives: Despite the recognized importance and distinctive characteristics of the intestinal lymphatic pathway in drug absorption, its pharmacokinetic modeling remains largely unexplored. This study aimed to address this gap by developing a physiologically based pharmacokinetic model (PBPK) to represent the oral lymphatic uptake of halofantrine following a fatty meal. Methods: Using GastroPlus™ 9.8.3 and published literature data, halofantrine absorption, distribution, metabolism, and elimination in both fasting and fed states were modeled. As the used software does not directly simulate intestinal lymphatic transport, lymphatic involvement in the fed state was examined indirectly through parameter adjustments such as first-pass metabolism, pKa-driven solubility changes, and bile-salt-mediated solubilization, with the aid of molecular dynamics simulations under post-prandial pH. Results: The pharmacokinetic models revealed a reduction in the first-pass effect of halofantrine in the fed state compared to that in the fasting state. While adjustments in metabolism kinetics sufficed for constructing a representative PBPK model in the fasting state, capturing the fed-state profile required both modifications to metabolism kinetics and other parameters related to the structural rearrangements of halofantrine driven by the changes in intestinal pH following food intake. These changes were confirmed using molecular dynamics simulations of halofantrine in pHs reflecting the post-prandial conditions. Conclusions: This study underscores the need for further exploration and direct modeling of intestinal lymphatic uptake via PBPK models, highlighting its underexplored status in simulation algorithms. Moreover, the importance of integrating representative physicochemical factors for drugs, particularly in post-prandial conditions or lipid formulations, is evident. Overall, these findings contribute to advancing predictive regulatory and developmental considerations in drug development using post hoc analyses. Full article

Background/Objectives: Pulmonary lymphangitic carcinomatosis (PLC) is a rare, aggressive manifestation of metastatic cancer characterized by lymphatic infiltration of the lungs, typically indicating advanced disease and poor prognosis. Methods: This comprehensive narrative review evaluates the role of [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) imaging in assessing PLC. Results: Current evidence demonstrates that [18F]FDG PET/CT achieves high diagnostic accuracy, with sensitivity and specificity ranging from 86 to 97% and 84 to 100%, respectively, particularly when employing semiquantitative metrics such as peritumoral standardized uptake value (SUVmax) thresholds (e.g., ≥2.1). PET/CT surpasses high-resolution computed tomography (HRCT) in distinguishing PLC from mimics like pulmonary sarcoidosis by identifying distinct metabolic patterns: bronchovascular hypermetabolism in PLC versus subpleural nodular uptake in sarcoidosis. Prognostically, metabolic tumor burden (e.g., SUVmax × involved lobes) and novel cPLC classifications (localized to the ipsilateral or contralateral lung) independently predict progression-free survival. However, challenges persist, including non-specific tracer uptake in inflammatory conditions and variability in SUV measurements due to technical factors. Emerging digital PET/CT systems, with enhanced spatial resolution, may improve the detection of focal PLC and reduce false negatives. While [18F]FDG PET/CT is invaluable for whole-body staging, therapeutic monitoring and biopsy guidance, the standardization of protocols and multicenter validation of prognostic models are critical for clinical integration. Future research should explore novel tracers (e.g., PSMA for prostate cancer-related PLC) and machine learning approaches to refine diagnostic and prognostic accuracy. Conclusions: This review underscores the role and the transformative potential of [18F]FDG PET/CT in PLC management while advocating for rigorous standardization to maximize its clinical utility. Full article

Systemic cancer progression culminating in metastatic disease is implicitly dependent on tumour cell interactions with the vascular system. Indeed, different facets of the micro- and macro-vasculature can be regarded as rate-limiting ‘vascular checkpoints’ in the process of cancer dissemination. The underlying complex communication networks drive tumour neovascularization, angiogenesis, immunoregulation, activation of the coagulation system, angiocrine interactions, and non-angiogenic vascular responses across multiple cancer types. Yet, each cancer may represent a unique vascular interaction scenario raising a prospect of targeted modulation of blood and lymphatic vessels for therapeutic purposes, beyond the traditional notion of tumour anti-angiogenesis. While the emphasis of studies aiming to understand this circuitry has traditionally been on soluble, or ‘mono-molecular’ mediators, the rise of the particulate secretome encompassing heterogeneous subpopulations of extracellular vesicles (EVs; including exosomes) and particles (EPs) brings another dimension into the tumour–vascular communication web during the process of metastasis. EVs and EPs are nanosized cellular fragments, the unique nature of which lies in their ability to encapsulate, protect and deliver to target cells a range of bioactive molecular entities (proteins, RNA, DNA) assembled in ways that enable them to exert a wide spectrum of biological activities. EVs and EPs penetrate through biological barriers and are capable of intracellular uptake. Their emerging vascular functions in metastatic or infiltrative cancers are exemplified by their roles in pre-metastatic niche formation, thrombosis, vasectasia or angiocrine regulation of cancer stem cells. Here, we survey some of the related evidence supporting the biological, diagnostic and interventional significance of EVs/EPs (EVPs) in disseminated neoplastic disease. Full article

Background/Objectives: While the presence of inflammatory processes in stenotic aortic valves is acknowledged, no systematic characterization of the systemic immune reaction upon aortic valve stenosis (AS) has been performed yet. The hypothesis of this study was that AS induces a systemic inflammatory reaction linked with local processes in the heart. Methods: Murine wire injury (WI) to induce AS, or sham surgery, were performed prior to the 4-week assessment of AS severity, left ventricular (LV) function and hypertrophy with echocardiography (echo). Organ weights, levels of leukocytes, cytokines and costimulatory molecules in blood, heart, and peripheral immune organs (spleen, liver, lymph nodes), and immune cell uptake of Cy5-labelled perfluorocarbon nanoemulsions were measured. Results: Trends towards correlation were found between organ weights, myocardial immune cells and echo. Cytokine mRNA levels trended mainly towards an increase in heart and regional lymph nodes and a reduction in spleen and liver, and correlation with echo was more homogeneous after WI. Unchanged cytokine protein levels in myocardium and plasma trended to correlate with echo. A homogeneous pattern was found for echo and costimulatory molecule correlation, while PFC uptake by lymphatic cells was reduced upon AS. Conclusions: The results suggest a link between number and activation state of leukocytes in peripheral organs and cardiac processes in AS. Considering the pathological value of inflammation, it is crucial that future studies investigate if a modulation of the systemic inflammatory reaction relieves severity of AS and opposes development of heart failure. Full article

Autoimmune diseases such as multiple sclerosis (MS) are characterized by a loss of self-tolerance, driven by diminished regulatory T cell (Treg) function and elevated Th1/Th17 responses. Existing therapies broadly suppress the immune system without correcting this imbalance, often leading to adverse effects. LPX3, a novel small-molecule T cell immunoglobulin and mucin domain-containing 3 and 4 (Tim-3/4) receptor agonist, was developed to restore immune tolerance via Treg induction. In this study, LPX3 was formulated into a liposomal oral delivery system, enabling efficient uptake through the gastrointestinal tract and lymphatic targeting. In vitro and in vivo analyses confirmed LPX3’s ability to expand CD4⁺Foxp3⁺ Tregs in a dose-dependent manner. In a MOG-induced experimental autoimmune encephalomyelitis (EAE) mouse model of MS, both prophylactic and therapeutic oral administration of LPX3 significantly delayed disease onset, reduced symptom severity, and improved survival. Importantly, efficacy was achieved without antigen co-delivery, indicating an antigen-independent mechanism of immune modulation. LPX3 liposomes showed deep lymph node penetration and colocalization with immune cells, supporting its functional delivery to key immunological sites. These findings suggest LPX3 is a promising candidate for treating autoimmune diseases by re-establishing immune regulation through oral, antigen-agnostic tolerance induction. Full article

Background and Clinical Significance: Breast cancer-related lymphedema (BCRL) is a chronic condition affecting up to 20% of breast cancer survivors. Manual lymphatic drainage (MLD) has traditionally included techniques to redirect lymph flow toward alternative pathways when axillary drainage is impaired. However, emerging imaging techniques suggest that most lymph continues to drain toward the ipsilateral axilla, and this has led to the widespread uptake of treatment protocols that exclude traditional redirecting movements, even in cases where personalized imaging is unavailable. Case Presentation: This case report describes a woman with BCRL affecting the right arm and hand who underwent 3 years of conservative lymphedema therapy, including MLD and self-massage techniques that incorporated traditional redirection strategies. Pre-operative indocyanine green (ICG) lymphography, performed after prolonged conservative treatment, confirmed the presence of an open alternative drainage pathway bypassing the axilla and demonstrated dermal flow along the redirected pathways towards a previously described “radial” pathway. These findings suggest that targeted manual therapy may have reinforced or optimized this compensatory route. Conclusions: This case highlights the potential risk of relying on a single form of assessment and generalized cohort imaging studies to guide individualized MLD protocols. In the absence of personal imaging, prematurely abandoning traditional redirection techniques may limit opportunities to establish functional alternative pathways, particularly in early edema in patients who have this anatomical variation. ICG lymphography provides valuable insight into compensatory lymphatic drainage. However, until imaging protocols are standardized and individual imaging is widely accessible, retaining traditional MLD techniques for newly diagnosed BCRL may be crucial for optimizing treatment outcomes. Future research should explore the long-term impact of manual therapy on alternative pathway development and function. Full article

Background: Peptide amphiphile micelles (PAMs) are a promising lipid-based nanotechnology currently in development for a variety of applications ranging from atherosclerosis to cancer therapy. Especially relevant for immune applications, PAMs improve trafficking through lymphatic vessels, enhance uptake by antigen-presenting cells, and inhibit the protease-mediated degradation of cargo. However, the creation of the peptide amphiphiles (PAs) necessary to induce micellization often requires modifying an immunotarget peptide with non-native moieties, which can induce the production of off-target antibodies. Methods: PAs containing different linkers between the antigen and non-native flanking regions were synthesized and physically characterized. BALB/c mice were then subcutaneously immunized on days 0 and 14 with these formulations and ELISAs were conducted on the sera collected from vaccinated mice on day 35 to evaluate antibody responses. Results: We determined that Palm₂K-M2_2–16-(KE)₄ PAMs elicited off-target antibody responses and sought to avoid these unintended responses by adding linkers in between the M2_2–16 antigen and the non-native flanking regions (i.e., Palm₂K- and -(KE)₄) of the PA. Most significantly, the addition of diproline linkers on either side of the M2_2–16 antigen conferred a loss of β-sheet structure, whereas changing the method of lipid attachment from Palm₂K- to Pam₂CS-induced the formation of primarily spherical micelles compared to a mixture of spherical and short cylindrical micelles. Despite these morphological changes, all linker-containing PAMs still induced the production of off-target antibodies. Excitingly, however, the formulation containing a Pam₂CS moiety (intended to mimic the adjuvanticity of the TLR2 agonist adjuvant Pam₂CSK₄) elicited high on-target antibody titers similar to those induced by PAMs co-delivered with Pam₂CSK₄. Conclusions: While the linkers tested did not completely eliminate the production of off-target antibodies elicited by the PAMs, the inclusion of a Pam₂CS moiety both increased the amount of on-target antibodies and improved the ratio of on-target to off-target antibodies in response to the M2_2–16 vaccine. Full article

This retrospective study was aimed at characterizing vascular malformations (VMFs) presenting for minimally invasive image-guided therapies (MIT) at a tertiary-care center and evaluating treatment regimens and image-based outcomes using MRI. We analyzed demographic, disease-related, and radiologic features of VMFs presenting to interventional radiology between May 2008 and August 2020 using compendium vascular anomaly (Compva) criteria. MIT and specific agents were evaluated, and treatment effects were assessed through volumetry and mean signal intensity (MSI) on multiparametric longitudinal MRI. The statistics included the paired t-test, ANOVA, and Fisher’s exact test. The cohort included 217 patients (mean age 30 ± 18.4 years; 134 female). Venous malformations were most common (47%). VMFs were frequently located in the head-neck region (23.5%), legs (23.04%), and arms (13.8%). Among 112 treatments, sclerotherapy was performed most frequently (63.9%), followed by embolization (19.3%). MRI showed a significant reduction in T2 MSI for venous (1107.95 vs. 465.26; p = 0.028) and decreased contrast media uptake for lymphatic malformations (557.33 vs. 285.33; p = 0.029) after sclerotherapy, while the lesion volumes did not change significantly (p = 0.8). These findings propose MRI-derived MSI as a potential non-invasive biomarker for assessing the response of VMF to MIT. By leveraging MRI, this study addresses challenges in managing rare diseases like VMFs, while advocating for standardized approaches and prospective studies to better link imaging findings with clinical outcomes. Full article

Lymphoscintigraphy evaluates the lymphatic system using radiocolloid compounds like ^99mTc-sulfur colloid and ^99mTc-nanocolloid, which vary in particle size and distribution timing. A local in-house Dextran kit (15–40 nm) was developed in 2005 and began clinical use in 2008 to localize sentinel lymph nodes; diagnose lymphedema; and detect lymphatic leakage. The normal drainage pattern remains unexplored. We retrospectively analyzed 84 upper extremity lymphoscintigraphies from 2008 to 2021. ^99mTc in-house Dextran was intradermally injected into both hands, followed by whole-body imaging at specified intervals (≤15 min; 16–30 min; 31–45 min; 46–60 min), with some receiving delayed imaging. Visual and quantitative analyses recorded axillary and forearm lymph nodes and liver, kidney, and urinary bladder activity. Results showed 92% (77/84) upper extremity lymphatic tract visualization within 45 min. Axillary node detection rates increased from 46% (≤15 min) to 86% (46–60 min). Delayed imaging further revealed nodes. Epitrochlear or brachial node visualization was rare (4%, 3/84). Hepatic, renal, and urinary bladder activity was noted in 54%, 71%, and 93% at 1 h, respectively. The axillary node uptake ratio was minimal (<2.5% of injection site activity; median 0.33%). This study characterizes normal upper extremity lymphatic drainage using ^99mTc in-house Dextran, offering insights into its clinical application Full article

The objective of this work was to develop a population physiologically based pharmacokinetic (popPBPK) model to characterize the variability in the clinical PK of monoclonal antibodies (mAbs) following intravenous (IV) and subcutaneous (SC) administration. An extensive literature search was conducted and clinical PK data for FDA-approved as well as non-approved mAbs were collected. Training and validation datasets of 44 and 9 mAbs exhibiting linear pharmacokinetics were used for model development. The variability in antibody PK was captured by accounting for different rate constants of pinocytosis (CL_up) and intracellular degradation (k_deg) for different mAbs. Typical values for CL_up and k_deg and their respective inter-antibody variabilities (${\omega }_{Clup}$, ${\omega }_{Kdeg})$ were estimated to be 0.32 L/h/L and 26.1 ${\mathrm{h}}^{-1}$ (73% and 46%). Varied absorption profiles following SC dosing were characterized by incorporating inter-antibody variability in local degradation (k_SC) and rate of lymphatic uptake (S_Lu) of mAbs. Estimates for typical k_SC and S_Lu values, and ${\omega }_{Ksc},{\omega }_{S\_Lu},$ were found to be 0.0015 ${\mathrm{h}}^{-1}$ and 0.54 (193%, and 49%). FDA-approved mAbs showed less local degradation (0.0014 ${\mathrm{h}}^{-1}$ vs. 0.0038 ${\mathrm{h}}^{-1}$) compared with other clinically tested mAbs, whereas no substantial differences in physiological processes involved in disposition were observed. To evaluate the generalizability of estimated PK parameters and model validation, the final popPBPK model was used to simulate the range of expected PK for mAbs following SC administration of nine different mAbs that were not used for model-building purposes. The predicted PK of all nine mAbs was within the expected range specified a priori. Thus, the popPBPK model presented here may serve as a tool to predict the clinical PK of mAbs with linear disposition before administering them to humans. The model may also support preclinical-to-clinical translation and ‘first-in-human’ dose determination for mAbs. Full article

In breast cancer, Targeted Axillary Dissection (TAD) allows for the selective excision of the sentinel lymph node (SLN) during primary tumor surgery. TAD consists of the resection of labelled SLNs prior to neoadjuvant chemotherapy (NACT). Numerous clinical and preclinical studies have explored the use of carbon-based colloids for SLN tattooing prior to NACT. However, carbon vectors show varying degrees of inflammatory reactions and, in about one fifth of cases, carbon particles migrate via the lymphatic pathway to other nodes, causing the SLN to mismatch the tattooed node. To overcome these limitations, in this study, we explored the use of melanin as a staining endogenous pigment. We synthesized and characterized melanin-loaded polymeric nanoparticles (Mel-NPs) and used them to tattoo lymph nodes in pig animal models given the similarity in the size of the human and pig nodes. Mel-NPs tattooed lymph nodes showed high identification rates, reaching 83.3% positive identification 16 weeks after tattooing. We did not observe any reduction in the identification as time increased, implying that the colloid is stable in the lymph node tissue. In addition, we performed histological and ultrastructural studies to characterize the biological behavior of the tag. We observed foreign-body-like granulomatous inflammatory responses associated with Mel-NPs, characterized by the formation of multinucleated giant cells. In addition, electron microscopy studies showed that uptake is mainly performed by macrophages, and that macrophages undergo cellular damage associated with particle uptake. Full article