Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

Application Name

Wound Healing (Scratch)

Confluence Assay

Version

2

1.

1

0.

1

0

Documentation Version

29

18.

08

09.2023 - 1

Input Image(s)

2D (standard and/or WSI) / Time Series / z-Stack / Multichannel Images; RGB or Grayscale (8 bit)

Input Parameter(s)

Regions of interest (optional)

Keywords

wound, healing, scratch

confluence, in-vitro,

directional

cell

migration

growth,

migration

growth rate, regeneration, proliferation,

growth

migration, microscopy

Short Description

Detection and measurement of the

(artificial) gap, the “scratch,” on a confluent cell monolayer for in-vitro wound healing research

percentage of the analysed image covered by adherent cells. Cell confluence is important for determining timings for splitting and harvesting cells.

References / Literature

For more information regarding

the assay

cell confluency check e.g. https://

pubmed

en.

ncbi.nlm.nih.gov/15576902/ or

wikipedia.org/wiki/Confluency or

https://

www.nature

bitesizebio.com/

articles/nprot.2007.30 ;

63887/cell-confluency/

Table of contents

Table of Contents
minLevel1
maxLevel7
excludeTable of contents

IKOSA Prisma

Wound Healing (Scratch)

Confluence Assay

You can use this image analysis application or any of our other applications in your account on the IKOSA platform. If it is not on in the list of available applications, please contact your organization's administrator or our team at support@kmlvisionsupport@ikosa.comai.

Application description

This application automatically measures the (artificial) gap, the so-called “scratch”, in images showing a cell monolayerpercentage of the analysed image covered by a monolayer of adherent cells. In addition to the scratch widthpercentage area covered with cells, areas that are ( not ) covered with cells are quantified (including/excluding single cells or cell-free areas). A ratio of each area (covered and uncovered) compared to the overall image size is also calculated. The application supports images from phase contrast and brightfield microscopy and arbitrary cell types. This analysis can also be performed on time lapse recordings (time series) to study directional cell migration in vitro, z-stacks, or multichannel images.

In the following sections, we provide the necessary input data requirements that are necessary to obtain accurate image analysis results and a description of the output files.

Input data requirements

Input image(s)

Input for this application is the following image data:

Image type

Color channels

Color depth (per channel)

Size (px)

Resolution (μm/px)

2D (standard and/or WSI),

Time Series,

Multichannel,

Z-Stack*

Check image formats

File formats

3 (RGB)

or

1 (Gray)

8 Bit

Standard images and WSI formats:

Max: 6144 x 6144

typically: 0.3-1.16

Image content

Microscopy (phase contrast or brightfield) image of a cell monolayer showing

an (artificial) gap with no

adherent cells, typically taken with 10x magnification.

Additional requirements

  • The measurement of scratch width is only supported for images showing a single (not multiple) scratch.

Info

*Please note: Z-stack images cannot be uploaded into IKOSA but still can be analyzed via IKOSA Prisma API.

Note

Important:

For all images, the following requirements apply:

  • The illumination must be constant throughout the image(s).

  • The sample must be in focus, i.e. no blurry regions in image(s).

Input parameter(s)

No additional input parameters are required for this application.

As an optional parameter, a single or multiple regions of interest (ROIs) can be defined in which the analysis should be performed (‘inclusion ROIs’).

Description of output files and their content

Files

File format

Description

1

csv

results.csv:

A csv file containing the analysis results for the input image or all inclusion ROIs.

2

jpg

results_vis/vis.jpg (2D image, no ROI), or

results_vis/t<time-step>_z<z-layer>_c<channel>.jpg (for time series, z-stack, or multichannel image, no ROI), or

results_vis/<roi-id>.jpg (2D image, ROI <roi-id>), or

results_vis/t<time-step>_z<z-layer>_c<channel>_<roi-id>.jpg (for time series, z-stack, or multichannel image, ROI <roi-id>):

A visualization of the analysis result for a specific time step (of a time series), z-layer (of a z-stack), or channel (of a multichannel image) for either the whole image (if no inclusion ROIs selected for analysis) or each individual inclusion ROI.

Description for visualizations:

  • Areas and contours

    • no color:

scratch area
    • cell free (

the largest
    • uncovered) area

)
  • Lines

    • magenta: linear fit to scratch “frontlines”, only calculated when the cell-covered area borders are not yet touching anywhere and if the borders are not too curvy

  • Image RemovedImage Removed
      • green: adherent cells and cell-covered area

  • red: bubbles (=cell-free areas outside the scratch)

  • cyan: free/floating cells and cell aggregates inside of scratch

  • Confluence Assay App output visualisationImage AddedConfluence Assay App input file visualisationImage Added

    Reference: Zaritsky A; Natan S; Kaplan D; Ben-Jacob E; Tsarfaty I (2015): Supplemental materials for "Live time-lapse dataset of in vitro wound healing experiments." GigaScience Database. http://dx.doi.org/10.5524/100118

    Info

    Please note: These files are only created if qualitative result visualization was requested when submitting the analysis job.

    Info

    Please note: the image quality might be reduced for the presentation in the technical docs.

    3

    json

    annotation_results.json:

    JSON file containing detected cells (cell covered regions). The position is measured from the left upper corner (1,1) of the image.

    4

    json

    roiMeta.json:

    A json file containing all information regarding the ROIs defined for the analysis job to ensure reproducibility. The file is empty if no ROIs were defined for analysis.

    5

    jpg

    rois_visualization.jpg, or

    t<time-step>_z<z-layer>_c<channel>_rois_visualization.jpg:

    An overview visualization to show locations of all analyzed ROIs for the 2D image or time step <time-step> of a time series, z-layer <z-layer> of a z-stack, or channel <channel> of a multichannel image.

    Info

    Please note: This file is only created if inclusion ROIs were defined for analysis.

    6

    json

    jobResultBundleMeta.json:

    A json file containing all information regarding the analysis job (application name and version, project, etc.) to ensure reproducibility.

    Info

    Please note: This file is only included if bundled or merged analysis jobs are downloaded.

    Info

    Please note:

    • The linear fit to the scratch borders (“frontlines”) may not be calculated for quite curvy scratch borders. In this case, frontline-related quantitative values will be zero.In the case of inclusion ROIs that are partially outside of the image, the ROIs are cropped to the areas that lie inside the image.

    • In the case of inclusion ROIs that are completely outside of the image, no analysis is performed. However, they are still listed in corresponding results files.

    • A <roi-id> is generated automatically by the application corresponding to the creation date of a ROI. The location of a ROI within an image with its specific <roi-id> can be seen in the file “rois_visualization.jpg.” ROIs that are completely outside of the image are not shown in this file.

    • All visualizations are downscaled to 25 megapixels (MP), if the original image or inclusion ROI is larger than 25 MP.

    Content

    results.csv

    Single csv-file

    If one or more time steps (of a time series), z-layers (of a z-stack), or channels (of a multichannel image) were specified, the results in a specific row refer to the time step/z-layer/channel specified in the corresponding column.

    If one or more ROIs were specified, the results in a specific row refer to the ROI specified in the corresponding columns, otherwise (empty ROI columns) the results refer to the whole image.

    Column NO.

    Column name

    Examples

    Value range

    Description

    1

    t

    3

    1 - 

    Time step, i.e. the position of the image in the time series.

    2

    z

    5

    1 - 

    z-layer, i.e. the position of the layer in the z-stack.

    3

    c

    2

    1 - 

    Channel, i.e. the position of the channel in the multichannel image.

    4

    roi_id

    ROI-03

    ROI-01 - 

    <roi-id> starting from “ROI-01”. Empty, if no inclusion ROI is specified and the whole image was analyzed.

    5

    roi_name

    “central”

    text

    Custom text to identify the ROI. Empty, if no inclusion ROI is specified and the whole image was analyzed.

    6

    roi_size [Px^2]

    1212212

    1 -

    Size of the ROI that was analyzed in pixels^2. The size of the whole image is given if no inclusion ROI is specified and the whole image was analyzed.

    7

    total

    cells_covered_area

    _without_scratch

    [Px^2]

    1011878

    0 - #of pixels in image

    Total area

    without scratch

    with adherent cells in Pixel^2, includes cell-covered area

    ,

    and free/floating cells

    and bubbles (= cell-free areas outside the scratch

    ).

    8

    total

    cells_covered_area_

    without_scratch

    ratio_ratio [%]

    68.6

    0 - 100

    Ratio of total area

    without scratch

    with adherent cells to the total area of the image.

    9

    scratch

    uncovered_area [Px^2]

    36698

    0 - #of pixels in image

    Total

    scratch area (

    cell-free area

    in center of image)

    in Pixel^2.

    Free/Floating cells inside of scratch are not considered part of the scratch.

    10

    scratch

    uncovered_area_ratio

    [%]

    31.4

    0 - 100

    Ratio of scratch area to total area of image. Free/Floating cells inside of scratch are not considered part of the scratch.

    11

    scratch_area_incl_free_cells [Px^2]

    37580

    0 - #of pixels in image

    Total scratch area (cell-free area in center of image) in Pixel^2. Free/Floating cells inside of scratch are considered part of the scratch.

    12

    scratch_area_incl_free_cells

    _ratio [%]

    31.

    6

    4

    0 - 100

    Ratio of

    scratch area to total area of image. Free/Floating cells inside of scratch are considered part of the scratch..

    13

    scratch_width_area [Px]

    400.5

    >=0

    Scratch width in Pixel, calculated by dividing the scratch_area by the “total length” of the scratch, i.e. the maximum distance between two points on the scratch border. Maximum value depends on the scratch orientation.

    14

    scratch_width_frontlines_mean [Px]

    435

    >=0 

    Scratch width in Pixel, estimated by mean distance between the two linearly fitted “frontlines” (scratch borders).Value is 0, if no frontlines have been fitted. Maximum value depends on the scratch orientation.

    15

    scratch_width_frontlines_min [Px]

    430

    >=0

    Scratch width in Pixel, estimated by minimum distance between the two linear fitted “frontlines” (scratch borders).Value is 0, if no frontlines have been fitted. Maximum value depends on the scratch orientation.

    16

    scratch_width_frontlines_max [Px]

    440

    >=0

    Scratch width in Pixel, estimated by maximum distance between the two linear fitted “frontlines” (scratch borders). 

    Value 0, if no frontlines have been fitted. Maximum value depends on

    the

    scratch orientation.

    17

    is_scratch_closed

    0

    0 or 1

    Boolean indicator if scratch is closed (1) or not (0).

    18

    cells_covered_area [Px^2]

    22143

    0 - #of pixels in image

    Total area of cell-covered region in Pixel^2. Bubbles (=

    cell-free

    areas outside the scratch) are not included in this

    area

    .

    19

    cells_covered_area_ratio [%]

    68.6

    0 - 100

    Ratio of cell-covered area

    to total area of image.

    Bubbles (= cell-free areas outside the scratch) are not included in this area.

    20

    cells_covered_area_incl_bubbles [Px^2]

    23053

    0 - #of pixels in image

    Total area of cell-covered region in Pixel^2. Bubbles (= cell-free areas outside the scratch) are included in this area.

    21

    cells_covered_area_incl_bubbles_ratio [%]

    68.9

    0 - 100

    Ratio of cell-covered area to total area of image. Bubbles (= cell-free areas outside the scratch) are included in this area.

    Info

    Please note: The parameters marked with an asterisk (*) are calculated using https://scikit-image.org/.

    Error information

    More information about errors can be found in the Application Error Documentation.

    Contact

    If you have any questions about this app, as well as suggestions or ideas for new ones, email us at support@kmlvisionsupport@ikosa.comai.

    Feel free to book a 30-minute meeting to speak with us about IKOSA and the apps!

    https://calendly.com/kmlvisionkolaido/book-the-ikosa-platform-demo