Pegylated Liposomal Doxorubicin Causes Kidney-limited Thrombotic Microangiopathy.

A definite causal link between pegylated liposomal doxorubicin (PLD) and kidney-limited thrombotic microangiopathy (TMA) remains unestablished. Here, we report 2 cases of PLD-induced kidney-limited TMA, 1 in a patient with myxofibrosarcoma and the other in a patient with liposarcoma. The 2 patients received a high cumulative dose of PLD, and both presented with a rise in serum creatinine and proteinuria. Kidney biopsy revealed TMA with chronic mesangiolysis and capillary wall double contouring. Neither patient had concomitant exposure to TMA-causing drugs, such as gemcitabine, anti-vascular endothelial growth factor agents, or mammalian target of rapamycin inhibitors. The work-up for secondary causes of TMA was negative in both patients. The cessation of PLD therapy led to improvement or stabilization in serum creatinine and proteinuria in both patients. These 2 cases provide a clear causal link between PLD and kidney-limited TMA. The high cumulative dose of PLD increases the risk of kidney TMA. Early recognition of PLD-induced kidney TMA can lead to timely cessation of PLD therapy and potentially preserve kidney function.

The approach to developing Ireland's first national health protection strategy and lessons learnt, December 2021 to October 2022.

The COVID-19 pandemic highlighted the importance of strengthening health protection worldwide. To address this as a public health priority in Ireland, between December 2021 and October 2022 the first national Health Protection Strategy (2022-2027) for the Irish Health Service Executive (HSE) was developed. We describe the approach taken to develop a first national health protection strategy for Ireland, and highlight the key lessons learned. Key steps in strategy formation included detailed stakeholder analysis, exploration of the context for the strategy and development of a comprehensive consultation plan. Two stakeholder consultation workshops were held. The first focused on defining strategic vision, aim and objectives, the second verified objectives and identified enablers. A subsequent e-consultation invited feedback from wider stakeholders. The published strategy outlines 10 strategic objectives and 11 enablers. Key lessons identified from the strategy development process include the importance of clear leadership and oversight, the value of identifying the context for change, ensuring adequate consultation planning, taking a multidisciplinary approach with strong stakeholder engagement and the need to maintain a strategic perspective. Lessons from our experience can support colleagues internationally to strategically set out their priorities for health protection beyond COVID-19.

What factors are associated with infant hearing aid use? A parent survey using the Theoretical Domains Framework.

OBJECTIVE: Hearing aid use is lowest in 0-3-year-olds with hearing loss, placing spoken language development at risk. Existing interventions lack effectiveness and are typically not based on a theoretically driven, comprehensive understanding of the factors influencing infant hearing aid use. The present study is the first to address this gap in understanding. DESIGN AND STUDY SAMPLE: A 55-item online survey based on the Theoretical Domains Framework (TDF) was completed by 56 parents of 0-3-year-old hearing aid users. RESULTS: Participants reported a wide range of barriers across TDF domains, which were associated with parent-reported hearing aid use and more pronounced in parents of lower hearing aid users. The most strongly reported domains across participants were "emotion" (e.g. feelings of worry when using hearing aids), "beliefs about capabilities" (e.g. belief in ability to use hearing aids consistently), and "environmental context and resources" (e.g. child removing hearing aids). CONCLUSIONS: Parents report a wider range of barriers to infant hearing aid use than existing investigations suggest and current interventions address. Interventions would benefit from: (i) targeting a wider range of TDF domains in their design; and (ii) implementing the present TDF survey to identify and target family-specific barriers to infant hearing aid use.

Adolescent binge drinking in the West of Ireland: associated risk and protective factors.

BACKGROUND: Alcohol is a leading cause of morbidity and mortality worldwide. Adolescence is when alcohol use typically begins. Harmful patterns of alcohol consumption, such as binge drinking, may emerge during adolescence and become established. This study aimed to examine potential risk and protective factors for binge drinking among 15-16-year-old adolescents in the West of Ireland. METHODS: This was a cross-sectional secondary analysis of 4473 participants from the Planet Youth 2020 Survey. The outcome was ever binge drinking, defined as ever consumption of five or more drinks in a two-hour period or less. Independent variables were selected a priori following review of peer-reviewed literature and were grouped as individual, parents and family, peer group, school, leisure time and local community factors. Statistical analysis was completed using SPSS version 27. Differences in medians and means for continuous variables were examined using the Mann-Whitney U test and Independent Samples t-test respectively. Multivariable logistic regression was used to examine independent associations between potential risk and protective factors and ever binge drinking. A p-value of < 0.05 was deemed statistically significant. RESULTS: The prevalence of ever binge drinking was 34.1%. Self-rated 'bad/very bad' mental health (adjusted Odds Ratio (aOR) 1.61, 95% CI 1.26-2.06, p < 0.001), current cigarette use (aOR 4.06, 95% CI 3.01-5.47, p < 0.001) and current cannabis use (aOR 2.79, 95% CI 1.80-4.31, p < 0.001) increased odds of ever binge drinking. Parental supervision (aOR 0.80, 95% CI 0.73-0.88, p < 0.001) and negative parental reaction to adolescent drunkenness (aOR 0.51, 95% CI 0.42-0.61, p < 0.001) reduced odds of ever binge drinking. Getting alcohol from parents increased odds of ever binge drinking (aOR 1.79, 95% CI 1.42-2.25, p < 0.001). Adolescents with friends who drink alcohol had almost five times higher odds of ever binge drinking (aOR 4.59, 95% CI 2.65-7.94, p < 0.001). Participating in team/club sports also increased odds of ever binge drinking (aOR 1.30, 95% CI 1.07-1.57, p = 0.008 for 1-4 times/week, aOR 1.52, 95% CI 1.07-2.16, p = 0.020 for ≥ 5 times/week). CONCLUSION: This study identifies individual and social environment factors associated with adolescent binge drinking in the West of Ireland. This can inform intersectoral action to protect adolescents from alcohol-related harm.

Limited transmission of SARS-CoV-2 in schools in Ireland during the 2020-2021 school year.

BackgroundThe role of schools in SARS-CoV-2 transmission has been a debated topic since the beginning of the COVID-19 pandemic.AimTo examine SARS-CoV-2 transmission in all schools in Ireland during the 2020-21 school year.MethodsIn a national descriptive cross-sectional study, we investigated PCR-confirmed cases of COVID-19 among students (aged < 20 years) and staff (aged ≥ 20 years) who attended school during their infectious period to identify school close contacts. SARS-CoV-2 PCR test results of all school close contacts were pooled to obtain an overall positivity rate and to stratify positivity rate by school setting and role (i.e. student or staff).ResultsIn total, 100,474 individuals were tested as close contacts in 1,771 schools during the 2020-21 school year. An overall close contact positivity rate of 2.4% was observed across all schools (n = 2,373 secondary cases). The highest positivity rate was seen in special schools (3.4%), followed by primary (2.5%) and post-primary schools (1.8%) (p < 0.001). Of the close contacts identified, 90.5% (n = 90,953) were students and 9.5% (n = 9,521) were staff. Overall, students had a significantly higher positivity rate than staff (2.4% vs 1.8%, p < 0.001).ConclusionThis study demonstrated that a low level of SARS-CoV-2 transmission occurred in Irish schools during the 2020-21 academic year. In the event of future pandemics, and as the COVID-19 pandemic continues, there is a need to carefully weigh up the harms and benefits associated with disrupted education to mitigate infectious disease transmission before reflexively closing classes or schools.

Sorafenib in Dupuytren and Ledderhose Disease.

Palmar and plantar fibromatosis are benign proliferative processes which present as a diffuse thickening or nodules of the hands and/or feet and may lead to flexion contractures, pain, and functional impairment known as Dupuytren and Ledderhose diseases, respectively. Current treatments are noncurative and associated with significant morbidity. Here, we report on the outcomes of 5 patients with advanced disease, no longer surgical candidates, treated with sorafenib. Sorafenib exhibited an expected safety profile. All 5 patients demonstrated objective responses as evaluated by a decrease in tumor size and/or tumor cellularity from baseline and all 5 patients reported subjective pain relief and/or functional improvement. Mechanistically, immunohistochemistry revealed patchy positivity for PDGFRß, a known target of sorafenib. The outcomes of these 5 patients suggest the safety and efficacy of a relatively well-tolerated oral agent in the treatment of Dupuytren and Ledderhose diseases and suggest the need for future controlled studies.

Soft Tissue Sarcoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

Soft tissue sarcomas (STS) are rare malignancies of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as retroperitoneal/intra-abdominal STS, desmoid tumors, and rhabdomyosarcoma. This portion of the NCCN Guidelines discusses general principles for the diagnosis and treatment of retroperitoneal/intra-abdominal STS, outlines treatment recommendations, and reviews the evidence to support the guidelines recommendations.

NCCN Guidelines® Insights: Gastrointestinal Stromal Tumors, Version 2.2022.

Gastrointestinal stromal tumors (GIST) are the most common type of soft tissue sarcoma that occur throughout the gastrointestinal tract. Most of these tumors are caused by oncogenic activating mutations in the KIT or PDGFRA genes. The NCCN Guidelines for GIST provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with these tumors. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including revised systemic therapy options for unresectable, progressive, or metastatic GIST based on mutational status, and updated recommendations for the management of GIST that develop resistance to specific tyrosine kinase inhibitors.

The emerging role of immunotherapy for the treatment of sarcoma.

Clinicians caring for patients with sarcoma founded the field of cancer immunotherapy. Despite this, contemporary success with immunotherapy for sarcoma has been limited. Here, we review immunotherapy for sarcoma including Coley's toxins, interleukin-2, adoptive cell transfer, and checkpoint blockade. We detail recent and ongoing efforts to combine checkpoint blockade with other immune modulators, surgery, or radiation. These results, along with ongoing investigations, have identified immunotherapeutic approaches as a promising avenue for progress in advanced sarcomas.

NCCN Guidelines Insights: Soft Tissue Sarcoma, Version 1.2021.

The NCCN Guidelines for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with soft tissue sarcomas. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including the development of a separate and distinct guideline for gastrointestinal stromal tumors (GISTs); reconception of the management of desmoid tumors; inclusion of further recommendations for the diagnosis and management of extremity/body wall, head/neck sarcomas, and retroperitoneal sarcomas; modification and addition of systemic therapy regimens for sarcoma subtypes; and revision of the principles of radiation therapy for soft tissue sarcomas.

Overweight and obesity in shift workers: associated dietary and lifestyle factors.

BACKGROUND: Approximately 17% of the European Union workforce is engaged in shift work. Shift work has been associated with a number of chronic conditions, including obesity and obesity-related metabolic diseases. The aim of this study was to explore the dietary and lifestyle behaviours of shift workers with a healthy vs. overweight/obese body mass index (BMI). METHODS: A cross-sectional study was conducted on 1080 shift workers using a 15-min, telephone-administered questionnaire developed from qualitative research on Irish shift workers and national dietary intake data. Demographic and work-related factors, as well as dietary and lifestyle behaviours were recorded. BMI was calculated using self-reported height and weight. Univariate and multivariate logistic regression methods were used to analyze data according to BMI category. RESULTS: Over 40% of shift workers were classified as overweight or obese. Multivariate analysis indicated that being male [P < 0.001, aOR = 2.102, 95% CI (1.62-2.73)] and middle- or older-aged were independently associated with overweight and obesity [P < 0.001, aOR = 2.44 95% CI (1.84-3.24) and P < 0.001, aOR = 2.9 95% CI (1.94-4.35), respectively]. Having a medium-high consumption of fried foods was independently associated with overweight and obesity [aOR = 1.38, 95% CI (1.06-1.8)]. CONCLUSIONS: Similar to the general population, overweight and obesity were strongly associated with male sex and middle- or older-age. Male shift workers may benefit from targeted dietary and lifestyle advice specifically focused on limiting fried foods to help protect against overweight and obesity.

No evidence of secondary transmission of COVID-19 from children attending school in Ireland, 2020.

As many countries begin to lift some of the restrictions to contain COVID-19 spread, lack of evidence of transmission in the school setting remains. We examined Irish notifications of SARS-CoV2 in the school setting before school closures on 12 March 2020 and identified no paediatric transmission. This adds to current evidence that children do not appear to be drivers of transmission, and we argue that reopening schools should be considered safe accompanied by certain measures.

A Phase I Study of Binimetinib (MEK162) Combined with Pexidartinib (PLX3397) in Patients with Advanced Gastrointestinal Stromal Tumor.

LESSONS LEARNED: The combination of pexidartinib and binimetinib was safe and tolerable and demonstrated encouraging signs of efficacy in two patients with advanced gastrointestinal stromal tumor (GIST) refractory to tyrosine kinase inhibitors (TKIs).Molecular profiling of GISTs at diagnosis and upon progression may provide insight into the mechanisms of response or resistance to targeted therapies.Additional trials are needed to further explore combined KIT and MEK inhibition in treatment-naïve and TKI-refractory patients with advanced GIST. BACKGROUND: Nearly all patients with advanced gastrointestinal stromal tumor (GIST) develop resistance to imatinib, and subsequent treatments have limited efficacy. Dual inhibition of KIT and MAPK pathways has synergistic antitumor activity in preclinical GIST models. METHODS: This was an investigator-initiated, phase I, dose escalation study of the MEK inhibitor binimetinib combined with pexidartinib, a potent inhibitor of CSF1R, KIT, and FLT3, in patients with advanced or metastatic GIST who progressed on imatinib. The primary endpoint was phase II dose determination; secondary endpoints included safety, tolerability, and efficacy. An expansion cohort to further evaluate safety and efficacy was planned. RESULTS: Two patients were treated at dose level one (binimetinib 30 mg b.i.d. and pexidartinib 400 mg every morning and 200 mg every evening), after which the study was terminated by the manufacturer. No dose-limiting toxicities (DLTs) were reported, and treatment was well tolerated. The only grade ≥3 treatment-emergent adverse event (TEAE) was asymptomatic elevated creatine phosphokinase (CPK). Both patients had a best response of stable disease (SD) by RECIST. Progression-free survival (PFS) and overall survival (OS) were 6.1 and 14.6 months, respectively, in one patient with five prior lines of therapy. The second patient with NF1-mutant GIST had a 27% decrease in tumor burden by RECIST and remains on study after 19 months of treatment. CONCLUSION: Pexidartinib combined with binimetinib was tolerable, and meaningful clinical activity was observed in two imatinib-refractory patients.

A phase Ib study of BGJ398, a pan-FGFR kinase inhibitor in combination with imatinib in patients with advanced gastrointestinal stromal tumor.

Background Preclinical studies suggest that imatinib resistance in gastrointestinal stromal tumor (GIST) can be mediated by MAP-kinase activation via fibroblast growth factor (FGF) signaling. In FGF stimulated GIST cell lines, BGJ398, a pan-FGFR kinase inhibitor in combination with imatinib, was cytotoxic and superior to imatinib therapy alone. In FGF-dependent GIST, the combination of BGJ398 and imatinib may provide a mechanism to overcome imatinib resistance. Methods This phase Ib study of BGJ398 and imatinib was performed in patients with imatinib refractory advanced GIST. A standard 3 + 3 dosing schema was utilized to determine the recommended phase II dose (RP2D). Two treatment schedules were evaluated incorporating imatinib 400 mg daily in combination with (A) BGJ398 daily 3 weeks on, 1 week off or (B) BGJ398 daily 1 week on, 3 weeks off. Results 16 patients enrolled. The median age was 54 years (range: 44-77), 81% were male, and the median number of lines of prior therapy was 4 [range: 2-6, 13 patients had ≥3 prior therapies]. 12 patients received treatment on schedule A [BGJ398 dose range: 25 - 75 mg]: 2 patients experienced dose limiting toxicities (DLT) (n = 1, myocardial infarction & grade (G)4 CPK elevation; n = 1, G3 ALT elevation) on schedule A (BGJ398 75 mg), significant hyperphosphatemia, an on-target effect, was not observed, implying the maximum tolerated dose was below the therapeutic dose. Following protocol amendment, 4 patients enrolled on schedule B [BGJ398 dose range: 75 - 100 mg]: no DLTs were observed. The most common treatment related adverse events occurring in >15% of patients included CPK elevation (50%), lipase elevation (44%), hyperphosphatemia (24%), anemia (19%), and peripheral edema (19%). Among the 12 evaluable patients, stable disease (SD) was the best response observed in 7 patients by RECIST v1.1 and 9 patients by CHOI. Stable disease ≥ 32 weeks was observed in 3 patients (25%). Median progression free survival was 12.1 weeks (95% CI 4.7-19.5 weeks). Conclusions Toxicity was encountered with the combination therapy of BGJ398 and imatinib. Due to withdrawal of sponsor support the study closed before the RP2D or dosing schedule of the combination therapy was identified. In heavily pre-treated patients, stable disease ≥ 32 weeks was observed in 3 of 12 evaluable patients. Trial Registration: NCT02257541 .

The Understanding of Communicative Intentions in Children with Severe-to-Profound Hearing Loss.

The ability to distinguish lies from sincere false statements requires understanding a speaker's communicative intentions and is argued to develop through linguistic interaction. We tested whether this ability was delayed in 26 children with severe-to-profound hearing loss who, based on vocabulary size, were thought to have relatively limited access to linguistic exchanges compared to typically hearing peers (n = 93). Children were presented with toy bears who either lied or made a false statement sincerely. Despite identifying speakers' knowledge/ignorance, deaf or hard of hearing (DHH) children were delayed in identifying lies and sincere false statements when matched for chronological age. When matched for receptive vocabulary, observed discrepancies diminished. Deaf children who experienced early access to conversations with their deaf parents demonstrated no delay. Findings suggest limited access to linguistic exchanges delays the development of a key pragmatic skill.

Complete Responses to Mitotane in Metastatic Adrenocortical Carcinoma-A New Look at an Old Drug.

PURPOSE: Based largely on reports that predate modern reporting standards, mitotane has been considered a systemic treatment option for both hormone control and antitumor control of metastatic adrenocortical cancer (ACC), although the therapeutic window is narrow. METHODS: We searched electronic medical records to identify patients with metastatic ACC treated and prescribed single-agent mitotane at Memorial Sloan Kettering Cancer Center from March 15, 1989-September 18, 2015. Reference radiologists reviewed all imaging and determined efficacy according to Response Evaluation Criteria in Solid Tumors 1.1. Patient demographics, toxicities, and treatment outcomes were reviewed. Next-generation sequencing was performed in selected cases. RESULTS: Thirty-six patients were identified. The mean age was 54 and 50% had functional tumors. Grade 3 or greater toxicities were documented in 16 out of 36 patients (44%) and 17% had documented long term adrenal insufficiency. Progression of the disease as the best response occurred in 30 out of 36 patients (83%) and one patient (3%) experienced clinical progression. Three patients achieved a complete response (CR) (8%), one patient achieved a partial response (3%), and one patient (3%) had stable disease after slow disease progression prior to initiation of therapy (durable for 6 months). All responders had nonfunctional tumors. Next-generation sequencing in two of the three CR patients was performed and failed to identify any novel alterations. CONCLUSION: In this retrospective series, mitotane had a low response rate and low tumor control rate; however, a disproportionately high complete response rate suggested it should be used in selected individuals. Adrenal insufficiency is common with mitotane use and aggressive treatment with steroid supplementation should be considered when appropriate to avoid excess toxicities. Biomarkers are desperately needed to further define this disease. IMPLICATIONS FOR PRACTICE: This is the first objective report of single-agent mitotane using modern objective criteria. Although the vast majority of patients did not respond (and toxicity was high), we identified a remarkable 8% complete response rate (i.e. cure) in biopsy proven stage IV adrenocortical cancer patients. Biomarkers are desperately needed for this rare disease.

Hydroxyapatite and fluorapatite coatings on dental screws: effects of blast coating process and biological response.

This paper describes the deposition of hydroxyapatite (HA) and fluorapatite (FA) onto titanium dental screws using a novel ambient temperature coating technique named CoBlast. The process utilises a coating medium and a blast medium sprayed simultaneously at the substrate surface. The blast medium was a sintered apatite (sHA) and two particles sizes (<106 and <180 µm) were used to assess their influence on the coating process. The influence of the coating process on the coating composition, coating adhesion, screw morphology and screw microstructure was examined. XRD analysis revealed the coating crystallinity was the same as the original HA and FA feedstock powders. Examining the screw's morphology, the threads of the CoBlasted screws exhibited rounding compared to the unmodified screw. This is due to the abrasive nature of the CoBlast process. The degree of rounding was more significant for the screws blasted with the 180 µm sHA than the 106 µm sHA. The blast media particle size significantly influences the surface roughness of both the substrate and coating and the microstructure of the substrate. The screws did not exhibit any loss of coating after insertion into a model bone material, indicating that the coating was strongly adhered to the substrate. There was no statistically significant difference in cell attachment and cell morphology on the unmodified substrates compared to the coated substrates. In conclusion, the CoBlast process can be used to deposit HA and FA onto complex geometries such as dental screws. The choice of blast medium particle size influences the screws morphology. The coating process does not negatively impact on the cell attachment and morphology in vitro.

High-throughput methods for screening liposome-macrophage cell interaction.

Carriers are often an essential element of drug delivery, bestowing attributes to their cargo such as biocompatibility, enhanced delivery, extended half-life and efficacy as well as mediating specific targeting at a tissue, cell or intracellular level. Liposomes and lipid-based carriers have been investigated for decades for this purpose, many achieving clinical approval including products such as Doxil® and Myocet™. Large-scale compound screens are routinely carried out in the field of drug discovery; however, less work has been done on harnessing high-throughput methods for carrier material screening. Screening the interaction of drug carriers and materials with cells is particularly critical for the development of emerging therapies, including biomedicines, in order to facilitate the development of safe and efficient drug products. Herein, a range of liposomes of neutral, anionic and cationic charge and others that are surface-modified with mannose residues were screened for cell interaction, toxicity and immune reactivity in THP-1-derived macrophages using a high-throughput format. Liposomes were seen to be efficacious in a concentration-dependent and, for mannosylated liposomes, mannosylated cholesterol linker length-dependent manner.

HGF induces epithelial-to-mesenchymal transition by modulating the mammalian hippo/MST2 and ISG15 pathways.

Epithelial to mesenchymal transition (EMT) is a fundamental cell differentiation/dedifferentiation process which is associated with dramatic morphological changes. Formerly polarized and immobile epithelial cells which form cell junctions and cobblestone-like cell sheets undergo a transition into highly motile, elongated, mesenchymal cells lacking cell-to-cell adhesions. To explore how the proteome is affected during EMT we profiled protein expression and tracked cell biological markers in Madin-Darby kidney epithelial cells undergoing hepatocyte growth factor (HGF) induced EMT. We were able to identify and quantify over 4000 proteins by mass spectrometry. Enrichment analysis of this revealed that expression of proteins associated with the ubiquitination machinery was induced, whereas expression of proteins regulating apoptotic pathways was suppressed. We show that both the mammalian Hippo/MST2 and the ISG15 pathways are regulated at the protein level by ubiquitin ligases. Inhibition of the Hippo pathway by overexpression of either ITCH or A-Raf promotes HGF-induced EMT. Conversely, ISG15 overexpression is sufficient to induce cell scattering and an elongated morphology without external stimuli. Thus, we demonstrate for the first time that the Hippo/MST2 and ISG15 pathways are regulated during growth-factor induced EMT.

Therapeutic aerosol bioengineering of siRNA for the treatment of inflammatory lung disease by TNFα gene silencing in macrophages.

The development of small interfering RNA (siRNA) to silence specific genes offers a new means of understanding and treating a range of respiratory diseases, including inflammatory lung disease. The alveolar macrophage (AM) is a key component of the inflammatory process in the lungs, associated with high levels of gene expression in inflammatory lung disease and therefore an attractive target for therapeutic siRNA. Delivery of siRNA to macrophages presents a significant delivery challenge, as fully differentiated alveolar macrophages are difficult to access and transfect. In this study we engineered particles suitable for inhalation that would efficiently transfect macrophages postinhalation. The process for encapsulation of siRNA in poly(lactic-co-glycolic acid) microparticles (MPs) was optimized using a double emulsion technique, and the resulting particles were characterized for size, shape, aerosol characteristics, encapsulation efficiency, and integrity of encapsulated siRNA. The cell uptake of the siRNA-loaded microparticles was determined by flow cytometry, confocal laser scanning microscopy (CLSM), and high-content analysis (HCA) with MPs capable of transfecting up to 55% of cells. Anti-TNFα siRNA-MPs were then prepared to study the functional activity of encapsulated siRNA in LPS-stimulated macrophages as a model of inflammation. The anti-TNFα siRNA-MPs were able to decrease TNFα expression by 45% over 48 h in the differentiated human monocytic cell line THP-1 compared to negligible knockdown using commercial transfection reagents and offered significant, sustained siRNA knockdown of TNFα in primary monocytes for up to 72 h.