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Spatial proteogenomic profiling uncovers sensitization strategies for antibody-drug conjugate in HER2-positive breast cancer.

Antibody-drug conjugates (ADCs) have transformed the treatment of HER2-positive breast cancer, yet resistance remains poorly understood. Using imaging mass cytometry, we profiled 157 regions of interest comprising 912,360 single cells from 47 HER2-positive/hormone receptor-negative breast cancers treated with SHR-A1811 in the FASCINATE-N trial. Spatial proteomic analyses identified two determinants of ADC response: elevated tumor-cell H3K27ac expression was associated with improved ADC efficacy, whereas collagen-positive fibroblasts mediated resistance. Combining ADC with the histone deacetylase inhibitor chidamide or the collagen-modulating agent losartan produced synergistic antitumor effects in preclinical models. These biomarkers and therapeutic vulnerabilities were independently validated in patients with advanced HER2-positive disease receiving trastuzumab deruxtecan. Moreover, based on these spatial features, we developed a clinically applicable ADC barrier prediction model that can be implemented using multiplex immunofluorescence. Taken together, our findings reveal actionable spatial determinants of ADC efficacy and suggest potential combination therapeutic strategies.

Humans↗

Arthrogryposis multiplex congenita and bilateral mid-brain infarction following maternal overdose of co-proxamol.

We report a case of arthrogryposis multiplex congenita secondary to fetal hypokinesia in a 41-week gestation infant following antenatal central nervous system injury. The mother's pregnancy was complicated by an episode of attempted self harm, with an overdose of co-proxamol at 22 weeks of gestational age, and by the use of cocaine in combination with excess alcohol intake. Magnetic resonance imaging showed bilateral mid-brain cysts and marked atrophy of the basal ganglia and thalami.

Acetaminophen↗

Clinical perspectives in the diagnosis of thyroid disease.

BACKGROUND: The wide array of available thyroid diagnostic tests can help provide accurate diagnoses for most cases of thyroid disease but can be confusing and costly when used inappropriately. METHODS: Published articles were reviewed and combined with the author's clinical experience and data collected from patients. RESULTS: The discussions focus on confusing aspects of thyroid diagnostic tests, the use and limitations of the thyrotropin test to screen for thyroid dysfunction, biological factors that complicate the interpretation of this and other thyroid diagnostic tests, and a combined clinical and laboratory approach to (a) thyroid diseases with only one important dimension ("simplex" conditions) and (b) thyroid diseases with several important dimensions ("multiplex" conditions). CONCLUSION: The optimal use of thyroid diagnostic tests is patient-specific and depends on the patient's specific thyroid disease, the stage of disease, and coexisting medical conditions.

Clinical Laboratory Techniques↗

Nanoparticle coding: size-based assays using atomic force microscopy.

Described herein is a novel strategy for the construction and interrogation of an assay platform based on (1) the size encoding of labeled nanoparticles; (2) the high imaging resolution of atomic force microscopy; and (3) evaporatively driven self-assembly of dense nanoparticle layers. This strategy employs two different sized nanoparticles that couple in the presence of a target analyte. In this example, one set of particles is a few hundred nanometers in size and acts as a capture substrate, while a second set of smaller particles serve as the analyte label. Thus, by forming an evaporatively assembled layer from a mixture of the two particle dispersions, the imaged size of the smaller particles when bound to the larger capture particles identifies the presence of the analyte. This letter demonstrates the feasibility of our bar-code strategy by concept tests using the binding specificity of biotin-modified silica nanoparticles (300-nm diameter) with streptavidin-labeled gold nanoparticles (10-nm diameter). The potential to extensively multiplex this assay strategy is briefly discussed.

Journal Article↗

The fluorescence bioassay platforms on quantum dots nanoparticles.

In this paper, we present the optical properties and the platforms on fluorescent quantum dots for biological labeling, biomedical engineering and biosensor in molecular imaging. Quantum dots possess several properties that make them very attractive for fluorescent tagging: broad excitation spectrum, narrow emission spectrum, precise tunability of their emission peak, longer fluorescence lifetime than organic fluorophores and negligible photobleaching. We describe how to take such advantages of quantum dots to develop the technology and employ it to build assay platforms. Finally, ultrasensitivity, multicolor, and multiplexing of the technology of semiconductor quantum dots open up promising and interesting possibilities for bioassay platform.

Biotechnology↗

T cell subsets of urine-derived lymphocytes (UDLs) serve as an indicator of TILs and reflect immunological sex differences in bladder cancer.

BACKGROUND: Bladder cancer is unique among visceral malignancies in that urine, which can be easily obtained, has prolonged contact with bladder tumors. Urinary biomarkers offer the potential to provide insight into the host and tumor immune microenvironment to guide therapeutic strategies. We evaluated the immune cellular composition of urine (urine-derived lymphocytes (UDLs)) versus tumor (tumor-infiltrating lymphocytes (TILs)). METHODS: We employed high-dimensional flow cytometry analyses on immune cells from tumors (TILs), urine (UDLs), and peripheral blood (peripheral blood mononuclear cells) among patients with bladder cancer. We performed multiplexed immunofluorescence (mIF) of matched tumors to provide spatial context to our findings, comparing deep/invasive and superficial/urine-facing regions of matched tumors. RESULTS: Our findings suggest that the CD4+ and CD8+ T cell subsets of UDLs characterized by flow cytometry had similar phenotypic profiles to those found in TILs (cell clusters quantified by multidimensional scaling and differentiation states). Results of mIF imaging with a panel of phenotypic and functional T cell markers suggested that UDLs reflected TILs in both superficial and deep tumor sections. We also found sex-dependent patterns in TILs and UDLs, indicating the male bladder cancer tumor microenvironment is enriched in exhausted CD4+ and CD8+ T cells, while the female bladder cancer microenvironment is enriched for activated T cells. CONCLUSIONS: Assessment of UDLs opens avenues of non-invasive biomarker development in clinical settings where bladder cancer TILs are hypothesized to predict clinical response. UDLs may also reflect sex-based differences in antitumor immunity.

Humans↗

Piezo dispensed microarray of multivalent chelating thiols for dissecting complex protein-protein interactions.

The fabrication of a novel biochip, designed for dissection of multiprotein complex formation, is reported. An array of metal chelators has been produced by piezo dispensing of a bis-nitrilotriacetic acid (bis-NTA) thiol on evaporated gold thin films, prestructured with a microcontact printed grid of eicosanethiols. The bis-NTA thiol is mixed in various proportions with an inert, tri(ethylene glycol) hexadecane thiol, and the thickness and morphological homogeneity of the dispensed layers are characterized by imaging ellipsometry before and after back-filling with the same inert thiol and subsequent rinsing. It is found that the dispensed areas display a monotonic increase in thickness with increasing molar fraction of bis-NTA in the dispensing solution, and they are consistently a few Angströms thicker than those prepared at the same molar fraction by solution self-assembly under equilibrium-like conditions. The bulkiness of the bis-NTA tail group and the short period of time available for chemisorption and in-plane organization of the dispensed thiols are most likely responsible for the observed difference in thickness. Moreover, the functional properties of this biochip are demonstrated by studying multiple protein-protein interactions using imaging surface plasmon resonance. The subunits of the type I interferon receptor are immobilized as a composition array determined by the surface concentration of bis-NTA in the array elements. Ligand dissociation kinetics depends on the receptor surface concentration, which is ascribed to the formation of a ternary complex by simultaneous interaction of the ligand with the two receptor subunits. Thus, multiplexed monitoring of binding phenomena at various compositions (receptor densities) offers a powerful tool to dissect protein-protein interactions.

Chelating Agents↗

A review and new report of medial temporal lobe dysfunction as a vulnerability indicator for schizophrenia: a magnetic resonance imaging morphometric family study of the parahippocampal gyrus.

A central question in schizophrenia research is which brain abnormalities are independent of psychosis and which evolve before and after psychosis begins. This question can be addressed by longitudinal neuroimaging studies beginning in the prodrome, but at present there is only one published study. We reviewed the literature on structural brain imaging in persons with chronic and first episode schizophrenia, nonpsychotic persons at genetic high risk, and persons thought to be at risk for imminent psychosis ("prodromal" persons). Medial temporal lobe (MTL), especially hippocampal, volume alterations are among the most robust brain vulnerabilities for schizophrenia. Because verbal declarative memory (VDM) deficits are prominent and the parahippocampal gyrus (PHG) is considered to be centrally involved with the hippocampus in VDM processing, we analyzed PHG data from a family study of schizophrenia. Patients with schizophrenia and nonpsychotic relatives from "multiplex" families (families with multiple persons with schizophrenia) had significantly smaller right parahippocampal anterior (PHa) volumes than controls. Marginally significant findings were observed for the left PHa. Unexpectedly, relatives from "simplex" families (families with only one person with schizophrenia) had significantly larger PH posterior volumes than controls and did not differ from controls on PHa. Results provide some support for the hypothesis that the vulnerability to schizophrenia includes abnormal volumes of the PHG. These data provide additional support for the hypothesis that some MTL abnormalities in schizophrenia are independent of psychosis, at least in families with presumably high genetic loading. Implications of genetic risk studies for prodromal research are discussed.

Adult↗

The central representation area of the radial nerve in the goat, studied by the axon reaction.

The central representation area of the radial nerve has been investigated in the goat, using the axon reaction. The retrograde changes after a two or six weeks survival time have been used to study both its position and architecture. Reconstructions have been made using a computer assisted approach. In the goat the central representation area of the radial nerve is situated in the dorsolateral part of the lateral motoneuronal cell group, extending from caudal C6 to caudal T1. It begins very small in C6, enlarges through C7, reaches its maximal diameter in C8, from where it gradually decreases to end in caudal T1. The contribution of the C6 segment to the central representation area of the radial nerve in the goat is in agreement with findings in some other species but it contrasts with the macroscopic origin of the radial nerve in ruminants. It is suggested that this finding, together with the statistically significant reduction in the number of alpha motoneurons at the C6 level in calves affected with Arthrogryposis Multiplex Congenita (AMC) in the forelimbs, may prove an at least partial involvement of the radial nerve in the pathogenesis of this disease, which is also suggested by clinical symptoms.

Animals↗

Transcriptional profiling of degraded RNA in cryopreserved and fixed tissue samples obtained at autopsy.

BACKGROUND: Traditional multiplexed gene expression methods require well preserved, intact RNA. Such specimens are difficult to acquire in clinical practice where formalin fixation is the standard procedure for processing tissue. Even when special handling methods are used to obtain frozen tissue, there may be RNA degradation; for example autopsy samples where degradation occurs both pre-mortem and during the interval between death and cryopreservation. Although specimens with partially degraded RNA can be analyzed by qRT-PCR, these analyses can only be done individually or at low levels of multiplexing and are laborious and expensive to run for large numbers of RNA targets. METHODS: We evaluated the ability of the cDNA-mediated Annealing, Selection, extension, and Ligation (DASL) assay to provide highly multiplexed analyses of cryopreserved and formalin fixed, paraffin embedded (FFPE) tissues obtained at autopsy. Each assay provides data on 1536 targets, and can be performed on specimens with RNA fragments as small as 60 bp. RESULTS: The DASL performed accurately and consistently with cryopreserved RNA obtained at autopsy as well as with RNA extracted from formalin-fixed paraffin embedded tissue that had a cryopreserved mirror image specimen with high quality RNA. In FFPE tissue where the cryopreserved mirror image specimen was of low quality the assay performed reproducibly on some but not all specimens. CONCLUSION: The DASL assay provides reproducible results from cryopreserved specimens and many FFPE specimens obtained at autopsy. Gene expression analyses of these specimens may be especially valuable for the study of non-cancer endpoints, where surgical specimens are rarely available.

Journal Article↗

Cell array coupled with laser scanning cytometry allows easy analysis of changes in cyclin expression during the cell cycle. An application of cell array system.

To assess the potential of cell array technology, a cell array slide with 50 spots was designed specifically for automated analysis of changes in expression of cyclins A and B1 during the cell cycle at the cellular level. Cells harvested every 1 hour from 0 through 23 hours after synchronization by mitotic selection were spotted in duplicate on a glass slide. Each slide contained 48 spots representing 24 different cell cycle phases, and the remaining two spots were peripheral blood lymphocytes, which were included as negative control. This cell array provided temporal and spatial information related to changes in cyclin expression during the cell cycle in a single experiment. The present study indicates that expression analysis by cell array is novel approach for cell cycle studies. Furthermore, sophisticated multiplexed cell array technology has great potential for analyses of expression of specific genes during diverse cellular events at the cellular level.

Cell Cycle↗

Intracranial paramedian hourglass-shaped dermoid associated with hereditary steatocystoma multiplex.

This is the first report to describe the coexistence of two rare diseases, intracranial paramedian hourglass-shaped dermoid and steatocystoma multiplex. A 46-year-old female with a history of steatocystoma multiplex, bradydactylies and kyphosis showed oscillopsia, ataxia and hemifacial spasm. MRI findings suggested a giant dermoid cyst extending from the left middle temporal fossa to the cerebellopontine angle, and this was confirmed surgically. We propose the involvement of some genetic factor or pathological process common to both disorders, steatocystoma multiplex and dermoid. From the clinical point of view, patients with cystic skin lesion should also be checked for intracranial lesion.

Brain Neoplasms↗

Multiplexed hybridization detection of quantum dot-conjugated DNA sequences using surface plasmon enhanced fluorescence microscopy and spectrometry.

In this study, the general suitability of quantum dot (QD)-DNA conjugates for the surface plasmon enhanced fluorescence spectroscopy technique is demonstrated. Furthermore, the QD-DNA system is transferred to the platform of surface plasmon enhanced fluorescence microscopy. Using this technique together with a microarray format, in which the sensor-bound single-stranded catcher probes are organized in individual surface spots, results in a simultaneous qualitative analysis of QD-conjugated analyte DNA strands as multicolor images. A clear decomposition of different QD(x)()-DNA(y)() mixtures can be achieved for sequential, as well as mixture injections. Besides this, the study describes the successful approach of measuring spectrally resolved surface plasmon enhanced fluorescence signals derived from catcher probe hybridized QD-DNA conjugates.

Base Sequence↗

Spatial habitat radiomics predicts tertiary lymphoid structure status and identifies an IDO1+ migratory dendritic cell axis in breast cancer.

BACKGROUND: Tertiary lymphoid structures (TLS) are spatially organized immune niches associated with therapeutic response and favorable outcomes in breast cancer (BC). However, TLS assessment currently relies on invasive tissue-based analyses, and the biological mechanisms underlying imaging-based TLS prediction remain poorly understood. METHODS: We developed and validated a spatial heterogeneity-based radiomic TLS signature (shTLS) using dynamic contrast-enhanced MRI to non-invasively predict TLS status across multicenter BC cohorts. Spatial habitat radiomics were used to capture intratumoral and peritumoral immune-related heterogeneity. Integrated multi-omics analyses, including transcriptomics, pathomics, genomics, single-cell RNA sequencing, immunohistochemistry, and multiplex immunofluorescence, were performed to biologically interpret shTLS-defined subgroups. Functional drug-sensitivity assays were conducted to assess therapeutic implications. RESULTS: The shTLS model achieved robust predictive performance across independent cohorts and molecular subtypes. High shTLS scores were associated with immune-inflamed tumors characterized by spatially clustered activated T cells and dendritic cells (DCs). In contrast, shTLS-low tumors exhibited an immunosuppressive spatial niche with peripheral accumulation of CD4+ PD-1+ T cells and plasma cells, increased immune-tumor separation, and enhanced inflammatory and immunoregulatory signaling. An indoleamine 2,3-dioxygenase 1 (IDO1)-associated immunoregulatory program was observed in the shTLS-low tumors, which appeared to be preferentially expressed by LAMP3+CCR7+ migratory DCs. Pharmacologic inhibition of IDO1 enhanced chemotherapy and CDK4/6 inhibitor sensitivity in vitro. CONCLUSION: This study establishes spatial radiomics as a non-invasive approach to decode TLS-associated immune ecosystems and supports the presence of an IDO1-associated immunosuppressive phenotype, providing biological insight and translational rationale for patient stratification and future combination strategies.

Humans↗

Optical imaging fiber-based single live cell arrays: a high-density cell assay platform.

A high-density, ordered array containing thousands of microwells is fabricated on an optical imaging fiber. Each individually addressable microwell is used to accommodate a single living cell. A charged coupled device (CCD) detector is employed to monitor and spatially resolve the fluorescence signals obtained from each individual cell, allowing simultaneous monitoring of cellular responses of all the cells in the array using reporter genes (lacZ, EGFP, ECFP, DsRed) or fluorescent indicators. Yeast and bacteria cell arrays were fabricated and used to perform multiplexed cell assays with resolution at the single-cell level. Monitoring gene expression in single yeast cells carrying a two-hybrid system was used to detect in vivo protein-protein interactions. The single-cell array technology provides a new platform for monitoring the unique multiple responses of large populations of individual cells from different strains or cell lines. The rich data acquired by the cell array has the potential to be employed as a new tool for cell biology research as well as to improve cell-based high-throughput screening (HTS) applications, such as the validation of new disease-associated cellular targets and the early-stage evaluation of potential drug candidates.

Escherichia coli↗

Accurate multiplex polony sequencing of an evolved bacterial genome.

We describe a DNA sequencing technology in which a commonly available, inexpensive epifluorescence microscope is converted to rapid nonelectrophoretic DNA sequencing automation. We apply this technology to resequence an evolved strain of Escherichia coli at less than one error per million consensus bases. A cell-free, mate-paired library provided single DNA molecules that were amplified in parallel to 1-micrometer beads by emulsion polymerase chain reaction. Millions of beads were immobilized in a polyacrylamide gel and subjected to automated cycles of sequencing by ligation and four-color imaging. Cost per base was roughly one-ninth as much as that of conventional sequencing. Our protocols were implemented with off-the-shelf instrumentation and reagents.

Acrylic Resins↗

A bench-top megavoltage fan-beam CT using CdWO4-photodiode detectors. I. System description and detector characterization.

We describe the components of a bench-top megavoltage computed tomography (MVCT) scanner that uses an 80-element detector array consisting of CdWO4 scintillators coupled to photodiodes. Each CdWO4 crystal is 2.75 x 8 x 10 mm3. The detailed design of the detector array, timing control, and multiplexer are presented. The detectors show a linear response to dose (dose rate was varied by changing the source to detector distance) with a correlation coefficient (R2) nearly unity with the standard deviation of signal at each dose being less than 0.25%. The attenuation of a 6 MV beam by solid water measured by this detector array indicates a small, yet significant spectral hardening that needs to be corrected before image reconstruction. The presampled modulation transfer function is strongly affected by the detector's large pitch and a large improvement can be obtained by reducing the detector pitch. The measured detective quantum efficiency at zero spatial frequency is 18.8% for 6 MV photons which will reduce the dose to the patient in MVCT applications. The detector shows a less than a 2% reduction in response for a dose of 24.5 Gy accumulated in 2 h; however, the lost response is recovered on the following day. A complete recovery can be assumed within the experimental uncertainty (standard deviation <0.5%); however, any smaller permanent damage could not be assessed.

Equipment Design↗

Karyotyping human chromosomes by combinatorial multi-fluor FISH.

We have developed epifluorescence filter sets and computer software for the detection and discrimination of 27 different DNA probes hybridized simultaneously. For karyotype analysis, a pool of human chromosome painting probes, each labelled with a different fluor combination, was hybridized to metaphase chromosomes prepared from normal cells, clinical specimens, and neoplastic cell lines. Both simple and complex chromosomal rearrangements could be detected rapidly and unequivocally; many of the more complex chromosomal abnormalities could not be delineated by conventional cytogenetic banding techniques. Our data suggest that multiplex-fluorescence in situ hybridization (M-FISH) could have wide clinical utility and complement standard cytogenetics, particularly for the characterization of complex karyotypes.

Chromosome Aberrations↗