Molecular Pharmaceutics最新文献

{"title":"PET Imaging of Phosphorylated RIPK1 Reveals Necroptosis Activation In Vivo","authors":"Sun Mi Park, Tae Sup Lee, Jieun Lee, Jiwon Yoon, Bom Sahn Kim, Byung Seok Moon","doi":"10.1021/acs.molpharmaceut.6c00579","DOIUrl":"10.1021/acs.molpharmaceut.6c00579","url":null,"abstract":"<p>Necroptosis is a regulated, pro-inflammatory form ofprogrammedcell death implicated in degenerative and inflammatory diseases, withRIPK1 acting as a key upstream regulator. However, the utility ofexisting RIPK1 PET radiotracers, as well as various RIPK1 inhibitors,remains uncertain, as it is unclear whether they reflect total proteinabundance or phosphorylation-dependent activation (pRIPK1), limitingaccurate assessment of <em>in vivo</em> signaling. Unlikepreviously reported RIPK1 PET tracers that primarily reflect totalRIPK1 distribution, we investigated whether [<sup>18</sup>F]RIPA56-3-F([<sup>18</sup>F]<strong>1</strong>) uptake is associated with RIPK1 activation-relatedsignaling <em>in vivo</em>. [<sup>18</sup>F]<strong>1</strong> was synthesized via copper-mediated radiofluorination, and its radiochemicalproperties were characterized. <em>In vitro</em> uptake studieswere performed in ARPE-19 cells under sodium iodate-induced stressto assess the relationship between [<sup>18</sup>F]<strong>1</strong> uptake,pRIPK1 activation, and total RIPK1 expression. <em>In vivo</em> dynamic PET/CT imaging was conducted to evaluate pharmacokineticsand biodistribution. A retinal injury model induced by sodium iodatewas used for time-course imaging and quantitative analysis of radiotraceruptake. Pharmacologic validation was performed using the RIPK1 inhibitornecrostatin-1s. Ex vivo analyses, including immunohistochemistry,were conducted to correlate PET findings with pRIPK1 expression. [<sup>18</sup>F]<strong>1</strong> was obtained with a non-decay-correctedradiochemical yield of 37.7 ± 6.1% (n = 27), radiochemical purity>99%, and stability up to 4.5 h. In ARPE-19 cells, [<sup>18</sup>F]<strong>1</strong> uptake increased in parallel with early pRIPK1 activationand decreased at later time points despite sustained total RIPK1 expression. <em>In vivo</em> dynamic PET demonstrated favorable pharmacokinetics,with a pseudo-steady state observed at 60–80 min postinjection.Time-course analysis revealed that tracer uptake peaked at early stages(7–12 h) following sodium iodate administration and declinedthereafter, consistent with transient pRIPK1 activation. In the retinalinjury model, ocular uptake of [<sup>18</sup>F]<strong>1</strong> wassignificantly higher than in controls (3.38 ± 0.45 vs 1.52 ±0.21%ID/g; <em>P</em> < 0.0001) and was significantly reducedby necrostatin-1s treatment (<em>P</em> = 0.0096). PET signalwas detectable prior to overt structural degeneration and correlatedwith increased pRIPK1 expression. [<sup>18</sup>F]<strong>1</strong> uptakewas more closely associated with pRIPK1-related signaling activitythan with total RIPK1 expression, enabling noninvasive imaging ofnecroptosis-associated signaling <em>in vivo</em>. This activation-stateimaging approach allows detection of early molecular events precedingstructural damage and supports the use of [<sup>18</sup>F]<strong>1</strong> as a potential pharmacodynamic biomarker for assessing ","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4288–4297"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-Targeted Radionuclide Therapy with 161Tb Instigates Anticancer Immunity in “Cold” Murine Prostate Tumor","authors":"Juan Sun,&nbsp;Jiakun Guo,&nbsp;Xunhao Qi,&nbsp;Jiangtao Yang,&nbsp;Guanglin Wang,&nbsp;Guangming Zhou,&nbsp;Fenghua Meng,&nbsp;Zhiyuan Zhong","doi":"10.1021/acs.molpharmaceut.6c00650","DOIUrl":"10.1021/acs.molpharmaceut.6c00650","url":null,"abstract":"<p>Targeted radionuclide therapy (TRT) with ¹⁷⁷Lu holdsa huge clinical success in treating advanced prostate cancer patients.It is noted, however, that ¹⁷⁷Lu with moderate radiationenergy achieves effective tumor inhibition at a relatively high doseand has a low capacity to activate “cold” prostate tumor.In this study, we report that Sigma-1 receptor and prostate-specificmembrane antigen (PSMA) dual-targeted peptide (S1R/PSMA-P) labeledwith ¹⁶¹Tb, which emits locally high linear energy transfer(LET) Auger electrons, effectively inhibits prostate tumor and energizesanticancer immunity. ¹⁶¹Tb–S1R/PSMA-P exhibitedsignificantly enhanced cytotoxicity and immunogenic cell death over ¹⁷⁷Lu-labeled counterpart by inducing more DNA double-strandbreaks and reactive oxygen species. Of note, ¹⁶¹Tb–S1R/PSMA-Pachieved high tumor uptake and selectivity, induced a complete regressionrate of 60% at a single dose of 7.4 MBq in RM1-PSMA⁺/RM1tumor model, and sensitized RM1-PSMA⁺/RM1 tumor to αPD1immune checkpoint blockade therapy at a dose of 3.7 MBq resultingin a cure rate of 50% and durable antitumor immunity. Overall, ¹⁶¹Tb–S1R/PSMA-P emerges as a promising theranosticagent that is capable of mitigating prostate tumor by boosting anticancerimmunity.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4311–4321"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148381282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Multitechnique Spectroscopy Platform for Monitoring Heterogeneities in the Higher-Order Structure of mAb Therapeutics","authors":"Divya Agrawal,&nbsp;Srishti Joshi,&nbsp;Saxena Nikita,&nbsp;Sonam Sriwastaw,&nbsp;Anurag S. Rathore","doi":"10.1021/acs.molpharmaceut.5c01948","DOIUrl":"10.1021/acs.molpharmaceut.5c01948","url":null,"abstract":"<p>Comprehensive characterization of higher-order structure(HOS)is a regulatory prerequisite for monoclonal antibody (mAb) therapeutics,particularly in establishing biosimilarity. A significant analyticalchallenge lies in detecting the early onset of structural heterogeneitywithin bulk drug substances, where signal dilution often masks precursorstates of degradation. This study proposes a novel, multitechniquespectroscopy platform consisting of UV-vis, Far-UV circular dichroism,intrinsic and extrinsic fluorescence, and Fourier transform infrared(FTIR) spectroscopy coupled with chemometrics for monitoring heterogeneitiesin HOS during the thermal degradation of trastuzumab, an IgG1mAb therapeutic.While size exclusion chromatography (SEC) confirmed a progressive,monotonic accumulation of soluble aggregates, the proposed multitechniquespectroscopic platform yielded richer information. Intrinsic and extrinsicfluorescence identified an early conformational drift characterizedby tertiary core destabilization and hydrophobic exposure immediatelyupon thermal stress (&lt;1 h), well before the onset of global backboneunfolding detected by circular dichroism. Data fusion via principalcomponent analysis (PCA), biplot, and dendrogram allowed for a morenuanced understanding of the HOS evolution through the thermal stresstimeline. The data-fusion approach explained in this study offersa robust, high-resolution framework for monitoring structural consistencythrough direct HOS mapping, offering a powerful solution for monitoringthe quality of biotherapeutic products during stability studies aswell as for biosimilarity assessments.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4089–4100"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148100639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tuning the Structural Properties of a Single-Domain Antibody Scaffold for Improved Fibroblast Activation Protein Targeting","authors":"Joseph P. Gallant,&nbsp;Kendahl L. Ott,&nbsp;Ohyun Kwon,&nbsp;Adedamola Adeniyi,&nbsp;Kendall E. Barrett,&nbsp;Zachary T. Rosenkrans,&nbsp;Jason C. Mixdorf,&nbsp;Eduardo Aluicio-Sarduy,&nbsp;Jonathan W. Engle,&nbsp;Reinier Hernandez,&nbsp;Bryan P. Bednarz,&nbsp;Aaron M. LeBeau","doi":"10.1021/acs.molpharmaceut.6c00238","DOIUrl":"10.1021/acs.molpharmaceut.6c00238","url":null,"abstract":"<p>Fibroblast activation protein (FAP) is an attractivetarget forthe development of cancer theranostics due to its selective expressionon cancer-associated fibroblasts (CAFs). While a number of small-moleculeFAP inhibitors (FAPIs) have been developed, few biologics have beeninvestigated as FAP-targeting vectors. Camelid-derived single-domainantibodies, or variable-heavy-heavy domains (VHHs), offer a compellingalternative, combining high affinity with versatile engineering options.In this study, we first identified a novel anti-FAP VHH, F7, froman affinity-matured camelid phage display library. To investigatehow valency and molecular weight affected target engagement and <em>in vivo</em> properties, F7 was engineered into three formats:a monomer (F7), a tethered dimer (F7D), and an Fc-fusion protein (F7-Fc).All three were specific for FAP with the two bivalent constructs demonstratingpicomolar affinity. Positron emission tomography imaging in FAP-positivexenograft models revealed distinct pharmacokinetic profiles acrossconstructs, with notable differences in tumor uptake and clearance.F7 had rapid uptake and clearance, resulting in significantly highertumor uptake than FAPI-46. Low molecular weight bivalent F7D demonstratedsimilar kinetics but was retained by the tumor, resulting in a hightumor-to-blood ratio with secondary uptake limited to clearance organs.The largest construct, F7-Fc, resulted in the highest tumor uptakeand allowed for longitudinal imaging. Absorbed dose calculations confirmedthat tumors received significantly higher radiation doses comparedto normal tissues. These findings demonstrate that tuning VHH scaffoldsize and valency can improve biodistribution and retention, establishingF7-based constructs as promising targeting vectors for FAP.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4181–4189"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148534579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Investigation of the Impact of Sodium Citrate Buffers on Lipid Nanoparticles of circRNA or Linear mRNA","authors":"Shurong Zhou,&nbsp;Zitong Wang,&nbsp;You Xu,&nbsp;Tuo Meng,&nbsp;Stephanie Barrett,&nbsp;Guizhi Zhu","doi":"10.1021/acs.molpharmaceut.6c00671","DOIUrl":"10.1021/acs.molpharmaceut.6c00671","url":null,"abstract":"<p>Circular RNAs (circRNAs)are an emerging modality ofRNA medicine.By bypassing terminal degradation, circRNA is highly stable with prolongedprotein/peptide expression duration relative to its linear mRNA counterpart,which may benefit its disease therapeutic or prophylactic efficacy.Currently, mRNA-delivering ionizable lipid nanoparticles (LNPs) andtheir formulation conditions, such as buffer, are often adopted forthe delivery of circRNA delivery. However, it remains elusive whetherthe LNPs and their formulation methods optimized for mRNA are stilloptimal for the delivery of circRNA. Here, by comparing circRNA versusmRNA payloads, we investigated the impact of sodium citrate bufferconcentrations on the physicochemical properties and RNA deliveryefficiency of the resulting RNA-LNPs of three current FDA-approvedLNPs, DLin-MC3-DMA (MC3), SM-102, and ALC-0315, respectively. First,for each LNP formulated using the same sodium citrate buffer concentration,mRNA and circRNA showed comparable physicochemical characteristicsand <em>in vitro</em> transfection efficiency; by contrast,high-concentration sodium citrate compromised the <em>in vivo</em> expression of circRNA LNPs but not mRNA LNPs. Second, relative toSM-102 LNPs, MC3-LNPs showed a lower RNA expression efficiency inmice, especially for circRNA. Third, LNPs formulated using high-concentrationsodium citrate buffer showed comparable integrity of mRNA and circRNAafter multiday storage at room temperature. Overall, our findingsunderscore the differential impact of citrate buffer concentrationson different LNPs loaded with circRNA and mRNA, calling for the customizedoptimization of different LNPs for the delivery of mRNA and circRNA.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4333–4340"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148358500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiolabeled Mesoporous Silica Nanosystem Enables Long-Term Cell Tracking In Vivo","authors":"Mengxin Xu,&nbsp;Jiangsheng Li,&nbsp;Jiaqi Li,&nbsp;Hanbo Song,&nbsp;Junyi Chen,&nbsp;Yu Liu,&nbsp;Dongban Duan,&nbsp;Zhibo Liu","doi":"10.1021/acs.molpharmaceut.6c00288","DOIUrl":"10.1021/acs.molpharmaceut.6c00288","url":null,"abstract":"<p>The clinical advancement of cell therapy necessitatesprecise invivo tracking of functional cells, yet challenges persist in achievingthis goal. Herein, we introduce zirconium-89 (⁸⁹Zr)-labeledmesoporous silica nanoparticles (⁸⁹Zr-mSiO₂)as a robust platform for cell tracking via positron emission tomography(PET) imaging. The designed ⁸⁹Zr-mSiO₂ exhibitsexceptional biocompatibility and internalization efficiency into cells,owing to its unique mesoporous structure and stable Si–O–Zrbonds. Both in vitro and in vivo studies demonstrate the prolongedstability and minimal cytotoxicity of ⁸⁹Zr-mSiO₂, ensuring reliable and safe cellular labeling. Notably, ⁸⁹Zr-mSiO₂ exhibits negligible cell efflux, enabling precisedetection of cellular signals without interference. PET imaging of ⁸⁹Zr-mSiO₂-labeled cells in murine models allowsfor the real-time tracking of cell localization for up to 10 dayspostinjection. Overall, our findings highlight the potential of ⁸⁹Zr-mSiO₂ as a promising tool for long-term invivo tracking of functional cells, thus advancing the prospects ofcell therapy in a clinical setting.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4217–4226"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148434347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Safety of Pharmaceutical Nanosuspensions in Drug Delivery: Evidence, Knowledge Gaps, and Safety-By-Design Strategies","authors":"Yingying Ma,&nbsp;Liuying Wang,&nbsp;Yancai Wang","doi":"10.1021/acs.molpharmaceut.6c00558","DOIUrl":"10.1021/acs.molpharmaceut.6c00558","url":null,"abstract":"<p>Pooraqueous solubility remains a major barrier to small-moleculedrug development. Pharmaceutical nanosuspensions, composed mainlyof drug nanocrystals stabilized by small amounts of excipients, canimprove dissolution and have been translated into several oral productsand long-acting injectables. However, their simple compositions donot make them biologically inert. Nanosizing changes the surface area,dissolution, interfacial properties, aggregation, and interactionswith biological fluids, thereby affecting local and systemic safety.This review examines nanosuspension safety from a product-level perspective.It focuses on formulation states generated during storage, handling,administration, and biological exposure, with attention to particle-sizedistribution, large-particle tails, stabilizer coverage and free excipient,crystal form, dissolution behavior, redispersibility, and in-use stability.These attributes are linked to blood compatibility, complement activation,immune responses, route-specific toxicity, biodistribution, macrophage-associatedretention, depot persistence, clinical experience, and regulatorytranslation. Current evidence supports nanosuspensions under well-controlledconditions, especially for oral nanocrystal products and selectedlong-acting injectables. Key uncertainties remain for repeated intravenoususe, chronic pulmonary exposure, particle-specific biodistribution,depot reversibility, long-term tissue exposure, and vulnerable populations.Safety assessment should, therefore, connect critical quality attributeswith route-relevant exposure and biological responses, providing abasis for safety by design.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4003–4024"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148496877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proof-of-Concept Development and Preclinical Evaluation of a Microarray Patch Platform for Codelivery of Multiple Broadly Neutralizing Antibodies for HIV Prevention","authors":"M. Melissa Peet,&nbsp;Vivek Agrahari,&nbsp;Parbeen Singh,&nbsp;Lam Luong Hoai Nguyen,&nbsp;Louise A. Ouattara,&nbsp;Eun Sung Yang,&nbsp;Carolina Herrera,&nbsp;Amarendra Pegu,&nbsp;Theodore C. Pierson,&nbsp;Thanh D. Nguyen,&nbsp;Gustavo F. Doncel","doi":"10.1021/acs.molpharmaceut.5c01650","DOIUrl":"10.1021/acs.molpharmaceut.5c01650","url":null,"abstract":"<p>Broadly neutralizingantibodies (bnAbs)are advancing as a preventativeor treatment option for HIV infection, but currently must be administeredparenterally, typically as a large injection or infusion, an invasivemethod of delivery, especially for the pediatric population. Here,we present proof-of-concept data on a minimally invasive microneedle(MN) patch platform codelivering three bnAbs, PGT121, VRC07-523LS,and PGDM1400LS, from separate MN patch units or pixels. Each 1 cm² patch pixel, fabricated via solvent casting, contained ∼2mg of one bnAb. In ex vivo porcine skin tests, the MNs effectivelypenetrated the skin. When tested in vitro in PBS buffer, MNs quicklydissolved, fully releasing bnAbs within 10 min. VRC07-523LS and PGT121functionality was maintained during patch manufacturing, as confirmedby an in vitro HIV-1 neutralization assay, while PGDM1400LS lost somepotency. In a rat model, coadministration of 1 cm² patchunits for each bnAb resulted in systemic exposure by the first collectiontime point of 3 h, reaching maximal concentrations by day 3 of upto 68 μg/mL. These preliminary findings suggest that the MNpatch platform may serve as a promising alternative to injectablebnAb formulations for HIV prevention and treatment, particularly inneonates and infants, although further investigation is required toestablish its clinical utility. Additionally, the solid-state MN formulationof bnAbs may eliminate the need for cold-chain storage or distribution,making the patch particularly suitable for use in resource-limitedsettings.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4048–4057"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148443442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Targeted mRNA Delivery Using Bispecific Antibody-Lipid Nanoparticle Complexes","authors":"James Collin Hickey,&nbsp;Tracoyia Roach,&nbsp;Britteny Cassaidy,&nbsp;Rudolf Hergesheimer,&nbsp;Noah Franklin,&nbsp;Jeffrey Morin,&nbsp;Sarah Wagman,&nbsp;Justin Cohen,&nbsp;David Morrissey,&nbsp;Javier Chaparro-Riggers,&nbsp;Patrick Lim Soo","doi":"10.1021/acs.molpharmaceut.6c00239","DOIUrl":"10.1021/acs.molpharmaceut.6c00239","url":null,"abstract":"<p>Lipid nanoparticles (LNPs) are highly modular drug nanocarriersthat have significantly progressed in the development and applicationof novel RNA therapeutics. While instrumental in current vaccine andhepatic gene therapy applications, extrahepatic LNP delivery remainsa challenging hurdle, severely limiting clinical applications forindividualized therapies that require cellular- and tissue-specificenrichment. Novel platform development remains needed to generatetargeted LNPs capable of modeling targeted uptake in vitro prior toin vivo applications. Herein, we developed and utilized an antibody-basedtargeting bispecific-LNP (TbsAb-LNP) platform simultaneously bindingLNP polyethylene glycol motifs and desired cell surface markers. Bycolocalizing TbsAb-LNP complexes with desired cell surface markers,we enable mRNA-LNP accumulation in the desired cell types. We additionallyassessed the endosomal efficiency kinetics of TbsAb-LNP complexesgenerated at various bispecific loading ratios in a Galectin-9 invitro expression model. Leveraging this facile and modular platformthat eliminates the need for complex chemical conjugation approaches,we successfully achieved targeted LNP delivery to xhuCD3-expressinglymphoblasts and xmTfR1-expressing cell lines in vitro as well asxmTfR1-expressing cells in vivo. Enrichment of TbsAb-LNPs to spleniccells demonstrates the potential utility of this platform for clinicalvaccine and T-cell delivery applications.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4190–4202"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148519584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of [111In]In-CHX-A″-DTPA-αCD68 for ImmunoSPECT to Image Murine Macrophages","authors":"Anna E. Strong,&nbsp;Erika Belitzky,&nbsp;Ayla Vaughn Embs,&nbsp;Samantha Katz,&nbsp;Alessandra Cavaliere,&nbsp;Dijana Djureinovic,&nbsp;Borna Roohani,&nbsp;Michael Liu,&nbsp;Carla Rothlin,&nbsp;Jianmei W. Leavenworth,&nbsp;Lucia Jilaveanu,&nbsp;Harriet M. Kluger,&nbsp;Bernadette Marquez-Nostra","doi":"10.1021/acs.molpharmaceut.5c01902","DOIUrl":"10.1021/acs.molpharmaceut.5c01902","url":null,"abstract":"<p><strong>Purpose:</strong> High tumor-associated macrophage (TAM) abundanceis associated with poorer prognoses across many cancers, includingrenal cell carcinoma (RCC). CD68 is an established clinical biomarkerfor macrophages in patient tissues and is also expressed in mousemacrophages, making it an attractive target for bridging preclinicaland clinical imaging of macrophages. We developed an anti-mouse CD68(mCD68) immunoSPECT imaging agent to noninvasively quantify TAM burdenin vivo and evaluate response to macrophage-modulating treatment ina syngeneic RCC tumor model. <strong>Methods:</strong> [¹¹¹In]In-CHX-A″-DTPA-αCD68 was synthesized by optimizingchelator conjugation and radiolabeling conditions, then characterizedfor binding affinity, stability, and specificity by in vitro assays.In vivo specificity was assessed in the Renca syngeneic RCC modelby comparing biodistribution of [¹¹¹In]In-CHX-A″-DTPA-αCD68with that of the radiolabeled IgG isotype control. ImmunoSPECT signalwas correlated with ex vivo CD68 expression measured by flow cytometryof dissociated tumors and spleens. To evaluate response to macrophage-modulatingtreatment, a 2 × 2 factorial study was conducted in which Renca-allograftedmice received either anti-CSF1R or IgG control, followed by immunoSPECTimaging with [¹¹¹In]In-CHX-A″-DTPA-αCD68 orradiolabeled isotype control; organ-to-heart SUVR was correlated withex vivo CD68 expression by flow cytometry. <strong>Results:</strong> [¹¹¹In]In-CHX-A″-DTPA-αCD68 bound specificallyto CD68 in bone marrow-derived macrophages, with high binding affinity(K_D = 7.99 ± 2.26 nM) to the CD68 protein. In Renca-allograftedmice, immunoSPECT signal correlated strongly with ex vivo CD68 expressionmeasured by flow cytometry of dissociated tumor and spleen cells (<em>r</em> = 0.854). Biodistribution studies confirmed specific uptakein vivo, with 2-fold, 8-fold, and 8-fold greater uptake in tumor,spleen, and bone marrow, respectively, compared with the radiolabeledisotype control. Treatment with the macrophage-depleting anti-CSF1Rresulted in ∼40% lower tumor-to-heart SUVR with [¹¹¹In]In-CHX-A″-DTPA-αCD68 compared with the isotype control,despite no change in tumor volumes. ImmunoSPECT signal remained stronglycorrelated with ex vivo CD68 expression measured by flow cytometry(<em>r</em> = 0.952). <strong>Conclusions:</strong> This studydemonstrates the first example of immunoSPECT imaging of CD68 in vivo.ImmunoSPECT imaging of CD68 provides a direct, noninvasive measureof total TAM burden in RCC and represents a translatable approachfor monitoring response to macrophage-modulating treatments in preclinicalstudies.</p>","PeriodicalId":52,"journal":{"name":"Molecular Pharmaceutics","volume":"23 8","pages":"4079–4088"},"PeriodicalIF":4.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148373739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}