Journal: Scientific Reports

Article Title: A multiparametric fluorescence assay for screening aptamer–protein interactions based on microbeads

doi: 10.1038/s41598-022-06817-0

Figure Lengend Snippet: Principle of the multiplexed aptamer binding assay using VideoScan technology. (1) Dye/size-encoded microbead populations presenting different proteins on their surfaces are mixed (2) incubated with a fluorescence-labelled aptamer (3) dissolved in a binding buffer of choice. After removing unbound aptamers by washing, the microbead suspension was transferred into a cavity of a 96 well plate (4). The microbeads were allowed to settle down forming a microbead chip on the transparent bottom (5). A fluorescence microscope (6) is used to take pictures of the microbead chip (7). Imaging software analyses the pictures, recognises and counts microbeads, measures their surface fluorescence intensity and groups them into populations (8). Finally, for each population the referenced mean fluorescence intensity (rMFI) per microbead population is calculated (9). (10) Shows a 96-well microtiter plate placed into the VideoScan system.

Article Snippet: All measurements of aptamer-target interactions were done with our in-house developed fully automatised multispectral inverse fluorescence microscopy platform, called VideoScan , commercialised as Calaidoscan 100 (CS100) at Attomol GmbH (Germany) (Fig. ).

Techniques: Binding Assay, Incubation, Fluorescence, Suspension, Microscopy, Imaging, Software

Journal: Scientific Reports

Article Title: A multiparametric fluorescence assay for screening aptamer–protein interactions based on microbeads

doi: 10.1038/s41598-022-06817-0

Figure Lengend Snippet: Influence of ionic strength on aptamer binding. Microbeads coupled with ( A ) IFNγ, ( B ) thrombin, ( C ) streptavidin and ( D ) Pf LDH were incubated with their fluorescence-labelled aptamers in the presence of varying NaCl concentrations (0–1000 mM). The binding of the aptamer to its target was measured by quantifying the surface fluorescence of the microbeads using VideoScan technology (mean values, n = 2). The half-maximal value (ED 50 in mM) was calculated after fitting non-linear models (IFNγ-apta: EXD.2; T2-apta: LL.2; T1-apta, SA-apta, Pf LDH-apta: LL.3).

Article Snippet: All measurements of aptamer-target interactions were done with our in-house developed fully automatised multispectral inverse fluorescence microscopy platform, called VideoScan , commercialised as Calaidoscan 100 (CS100) at Attomol GmbH (Germany) (Fig. ).

Techniques: Binding Assay, Incubation, Fluorescence

Journal: Scientific Reports

Article Title: A multiparametric fluorescence assay for screening aptamer–protein interactions based on microbeads

doi: 10.1038/s41598-022-06817-0

Figure Lengend Snippet: Influence of pH value on aptamer binding. Microbeads coupled with ( A ) IFNγ, ( B ) thrombin, ( C ) streptavidin and ( D ) Pf LDH were incubated with their fluorescence-labeled aptamer in binding buffers (= corresponding selection buffer) of varying pH values. ( E ) Binding capacity of Pf LDH-apta to non-target proteins immobilised on fluorescence-labelled microbeads under varying pH values. The binding of all aptamers to their targets were measured by quantifying the surface fluorescence of the microbeads using VideoScan technology. All data are represented as mean ± SD (n = 4).

Article Snippet: All measurements of aptamer-target interactions were done with our in-house developed fully automatised multispectral inverse fluorescence microscopy platform, called VideoScan , commercialised as Calaidoscan 100 (CS100) at Attomol GmbH (Germany) (Fig. ).

Techniques: Binding Assay, Incubation, Fluorescence, Labeling, Selection

Journal: Journal of Clinical Microbiology

Article Title: Retrospective validation of MetaSystems’ deep-learning-based digital microscopy platform with assistance compared to manual fluorescence microscopy for detection of mycobacteria

doi: 10.1128/jcm.01069-23

Figure Lengend Snippet: (a) Diagnostic AFB smear concordance between a-DM and MM prior to discrepancy analysis. (b) Investigation of discrepant results between both methods. (c) Comparative overall concordance rate, positive-percent agreement (PPA), and negative-percent agreement (NPA) between both methods prior to and following discrepant analysis. PPA, percent positive agreement; NPA, negative percent agreement; OCR, overall concordance rate; No., number; TA, tracheal aspirate; BAL, bronchoalveolar lavage; BW, bronchial washings; MM, manual microscopy; a-DM, assisted digital microscopy; MTBC, Mycobacterium tuberculosis complex; MAC, Mycobacterium avium complex; NTM, non-tuberculous mycobacteria.

Article Snippet: MetaSystems assisted digital microscopy (a-DM) platform; in its current state and accordance with its European Union approval, requires final confirmation of AFB-positive results by trained digital reviewers.

Techniques: Diagnostic Assay, Microscopy

Journal: Journal of Clinical Microbiology

Article Title: Retrospective validation of MetaSystems’ deep-learning-based digital microscopy platform with assistance compared to manual fluorescence microscopy for detection of mycobacteria

doi: 10.1128/jcm.01069-23

Figure Lengend Snippet: (a) Comparative paired diagnostic accuracy of a-DM and MM compared to mycobacterial culture before discrepant analysis. (b) Three-way comparison table between a-DM, MM, and mycobacterial culture following discrepant analysis. (c) Post-discrepant analysis differences in paired sensitivities and specificities of both microscopic methods with 95% Cl and P value according to McNemar’s test. a Growth of MTBC ( n = 35) and NTM ( n = 32); b Growth of MTBC ( n = 1); c All digital slides initially observed to be AFB negative upon re-examination; d Growth of MTBC ( n = 1) and NTM ( n = 1); e Including six digital slides initially interpreted as doubtful; f Growth of MTBC ( n = 2) and NTM ( n = 3). Abbreviations: AFB, acid-fast bacilli; MM, manual microscopy; a-DM, assisted digital microscopy; TP, true positive; FP, false positive; TN, true negative, FN, false negative; 95% CI, 95% CI; MTBC, Mycobacterium tuberculosis complex; MAC, Mycobacterium avium complex; NTM, non-tuberculous mycobacteria; Se, sensitivity; Sp, specificity; Δ Se, difference in paired sensitivities; ΔSp: difference in paired specificities.

Article Snippet: MetaSystems assisted digital microscopy (a-DM) platform; in its current state and accordance with its European Union approval, requires final confirmation of AFB-positive results by trained digital reviewers.

Techniques: Diagnostic Assay, Comparison, Microscopy