/TraSig

Inferring cell-cell interactions from pseudotime ordering of scRNA-Seq data

Primary LanguageJupyter NotebookMIT LicenseMIT

Introduction

TraSig (Trajectory-based Signalling genes inference) identifies interacting cell types pairs and significant ligand-receptors based on the expression of genes as well as the pseudo-time ordering of cells. For any two groups of cells that are expected to overlap in time, TraSig takes the pseudo-time ordering for each group and the expression of genes along the trajectory as input and then outputs an interaction score and p-value for each possible ligand-receptor pair. It also outputs a summary score for cell type pairs by combining individual ligand-receptors' scores.

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Table of Contents

Get-started

Prerequisites

  • Python >= 3.6
  • Python side-packages:
    -- numpy >= 1.19.5
    -- pandas >= 0.23.4
    -- Bottleneck >= 1.3.2
    -- statsmodels >= 0.12.1 (required for post-analysis only)
    -- scipy >= 1.5.4 (required for post-analysis only)
    -- matplotlib >= 3.3.4 (required for post-analysis only)
    -- seaborn >= 0.11.0 (required for post-analysis only)

Installation

Install within a virtual environment

It is recommended to use a virtural environment/pacakges manager such as Anaconda. After successfully installing Anaconda/Miniconda, create an environment by following:

conda create -n myenv python=3.6

You can then install and run the package in the virtual environment. Activate the virtural environment by:

conda activate myenv

Make sure you have pip installed in your environment. You may check by

conda list

If not installed, then:

conda install pip

Then install TraSig, together with all its dependencies by:

pip install git+git://github.com/doraadong/TraSig.git

If you want to upgrade TraSig to the newest version, then first uninstall it by:

pip uninstall trasig

And then just run the pip install command again.

Not using virtural environment

If you prefer not to use a virtual envrionment, then you may install TraSig and its dependencies by (may need to use sudo):

pip3 install git+https://github.com/doraadong/TraSig.git

You may find where the package is installed by:

pip show trasig

Command-line

Run TraSig

Run TraSig by (arguments are taken for example):

main.py -i input -o output -d oligodendrocyte-differentiation-clusters_marques -g None -b ti_slingshot -n 1000 -s smallerWindow

The usage of this command is listed as follows:

usage: main.py [-h] -i INPUT -o OUTPUT -d PROJECT -g PREPROCESS -b MODELNAME
               [-t LISTTYPE] [-l NLAP] [-m METRIC] [-z NAN2ZERO] [-n NUMPERMS]
               [-p MULTIPROCESS] [-c NCORES] [-s STARTINGTREATMENT]
               [-a ALIGNTYPE] [-y GENEPAIRTYPE] [-f SMOOTH] [-v OVERLAP]
               [-r RATE] [-e ERRORTYPE] [-k ARATE] [-j BRATE]

optional arguments:
  -h, --help            show this help message and exit
  -i INPUT, --input INPUT
                        string, folder to find inputs
  -o OUTPUT, --output OUTPUT
                        string, folder to put outputs
  -d PROJECT, --project PROJECT
                        string, project name
  -g PREPROCESS, --preprocess PREPROCESS
                        string, preprocessing steps applied to the data /
                        project, default None
  -b MODELNAME, --modelName MODELNAME
                        string, name of the trajectory model
  -t LISTTYPE, --listType LISTTYPE
                        string, optional, interaction list type, default
                        ligand_receptor
  -l NLAP, --nLap NLAP  integer, optional, sliding window size, default 20
  -m METRIC, --metric METRIC
                        string, optional, scoring metric, default dot
  -z NAN2ZERO, --nan2zero NAN2ZERO
                        boolean, optional, if treat nan as zero, default True
  -n NUMPERMS, --numPerms NUMPERMS
                        integer, optional, number of permutations, default
                        10000
  -p MULTIPROCESS, --multiProcess MULTIPROCESS
                        boolean, optional, if use multi-processing, default
                        True
  -c NCORES, --ncores NCORES
                        integer, optional, number of cores to use for multi-
                        processing, default 4
  -s STARTINGTREATMENT, --startingTreatment STARTINGTREATMENT
                        string, optional, way to treat values at the beginning
                        of an edge with sliding window size smaller than nLap,
                        None/parent/discard/smallerWindow, default
                        smallerWindow, need to provide an extra input
                        'path_info.pickle' for 'parent' option
  -a ALIGNTYPE, --alignType ALIGNTYPE
                        string, optional, how to align edges, options:
                        unaligned/aligned-fixed/aligned-specific, default
                        unaligned
  -y GENEPAIRTYPE, --genePairType GENEPAIRTYPE
                        string, optional, identifier for the type of genes to
                        align, e.g. interaction/cell_cycle, default
                        interaction
  -f SMOOTH, --smooth SMOOTH
                        float, optional, smoothing parameter for splines,
                        default 1
  -v OVERLAP, --overlap OVERLAP
                        float, optional, overlap threshold for alignment,
                        default 0.5
  -r RATE, --rate RATE  integer, optional, sampling rate for aligned time
                        points, default 1
  -e ERRORTYPE, --errorType ERRORTYPE
                        string, optional, type of distance metric for
                        alignment (MSE, cosine or corr), default cosine
  -k ARATE, --aRate ARATE
                        float, optional, rate to sample parameter a for
                        alignment, default 0.05
  -j BRATE, --bRate BRATE
                        float, optional, rate to sample parameter b for
                        alignment, default 2.5

Prepare inputs for TraSig (from dynverse outputs)

For preparing inputs using user-defined trajectory (not from dynverse), see tutorial.

Given dynverse outputs, prepare inputs by (arguments are taken for example):

python prepare_inputs.py -i ../trajectory/input -o ../example/input -d oligodendrocyte-differentiation-clusters_marques -t ../trajectory/output/output.h5 -g None -b ti_slingshot -e None

The usage of this command is listed as follows:

usage: prepare_inputs.py [-h] -i INPUT -o OUTPUT -d PROJECT -t TRAJECTORYFILE
                         -g PREPROCESS -b MODELNAME [-e OTHERIDENTIFIER]
                         [-c LISTTYPE] [-cp PATHLR] [-y GENEPAIRTYPE]
                         [-yp PATHALIGN]

optional arguments:
  -h, --help            show this help message and exit
  -i INPUT, --input INPUT
                        string, folder to find inputs for trajectory inference
  -o OUTPUT, --output OUTPUT
                        string, folder to save inputs for TraSig
  -d PROJECT, --project PROJECT
                        string, project name
  -t TRAJECTORYFILE, --trajectoryFile TRAJECTORYFILE
                        string, trajectory output file from dynverse, default
                        ../trajectory/output/output.h5
  -g PREPROCESS, --preprocess PREPROCESS
                        string, preprocessing steps applied to the data /
                        project, default None
  -b MODELNAME, --modelName MODELNAME
                        string, name of the trajectory model
  -e OTHERIDENTIFIER, --otherIdentifier OTHERIDENTIFIER
                        string, optional, other identifier for the output,
                        default None
  -c LISTTYPE, --listType LISTTYPE
                        string, optional, interaction list type, default
                        ligand_receptor
  -cp PATHLR, --pathLR PATHLR
                        string, optional, path to the interaction list,
                        default
                        ../ligand_receptor_lists/ligand_receptor_FANTOM.pickle
  -y GENEPAIRTYPE, --genePairType GENEPAIRTYPE
                        string, optional, identifier for the type of genes to
                        align, e.g. interaction/cell_cycle, default
                        interaction
  -yp PATHALIGN, --pathAlign PATHALIGN
                        string, optional, path to the alignment genes list,
                        set as 'None' if not doing alignment or using
                        'interaction' for alignment, default None

Analyze outputs from TraSig

Analyze outputs by (arguments are taken for example):

python analyze_outputs.py -i ../example/input -o ../example/output -d oligodendrocyte-differentiation-clusters_marques -g None -p None -b ti_slingshot -p None -n 100000 -s smallerWindow

The usage of this command is listed as follows:

usage: analyze_outputs.py [-h] -i INPUT -o OUTPUT -d PROJECT -g PREPROCESS -b
                          MODELNAME [-t LISTTYPE] [-p OTHERIDENTIFIER]
                          [-l NLAP] [-m METRIC] [-z NAN2ZERO] [-n NUMPERMS]
                          [-s STARTINGTREATMENT] [-a ALIGNTYPE]
                          [-y GENEPAIRTYPE] [-f SMOOTH] [-v OVERLAP] [-r RATE]
                          [-e ERRORTYPE] [-k ARATE] [-j BRATE]

optional arguments:
  -h, --help            show this help message and exit
  -i INPUT, --input INPUT
                        string, folder to find TraSig's inputs
  -o OUTPUT, --output OUTPUT
                        string, folder to find TraSig's outputs
  -d PROJECT, --project PROJECT
                        string, project name
  -g PREPROCESS, --preprocess PREPROCESS
                        string, preprocessing steps applied to the data /
                        project, default None
  -b MODELNAME, --modelName MODELNAME
                        string, name of the trajectory model
  -t LISTTYPE, --listType LISTTYPE
                        string, optional, interaction list type, default
                        ligand_receptor
  -p OTHERIDENTIFIER, --otherIdentifier OTHERIDENTIFIER
                        string, optional, other identifier for the output,
                        default None
  -l NLAP, --nLap NLAP  integer, optional, sliding window size, default 20
  -m METRIC, --metric METRIC
                        string, optional, scoring metric, default dot
  -z NAN2ZERO, --nan2zero NAN2ZERO
                        boolean, optional, if treat nan as zero, default True
  -n NUMPERMS, --numPerms NUMPERMS
                        integer, optional, number of permutations, default
                        10000
  -s STARTINGTREATMENT, --startingTreatment STARTINGTREATMENT
                        string, optional, way to treat values at the beginning
                        of an edge with sliding window size smaller than nLap,
                        None/parent/discard/smallerWindow, default
                        smallerWindow, need to provide an extra input
                        'path_info.pickle' for 'parent' option
  -a ALIGNTYPE, --alignType ALIGNTYPE
                        string, optional, how to align edges, options:
                        unaligned/aligned-fixed/aligned-specific, default
                        unaligned
  -y GENEPAIRTYPE, --genePairType GENEPAIRTYPE
                        string, optional, identifier for the type of genes to
                        align, e.g. interaction/cell_cycle, default
                        interaction
  -f SMOOTH, --smooth SMOOTH
                        float, optional, smoothing parameter for splines,
                        default 1
  -v OVERLAP, --overlap OVERLAP
                        float, optional, overlap threshold for alignment,
                        default 0.5
  -r RATE, --rate RATE  integer, optional, sampling rate for aligned time
                        points, default 1
  -e ERRORTYPE, --errorType ERRORTYPE
                        string, optional, type of distance metric for
                        alignment (MSE, cosine or corr), default cosine
  -k ARATE, --aRate ARATE
                        float, optional, rate to sample parameter a for
                        alignment, default 0.05
  -j BRATE, --bRate BRATE
                        float, optional, rate to sample parameter b for
                        alignment, default 2.5

Tutorials

Github rendering disables some functionalities of Jupyter notebooks. We recommend using nbviewer to view the following tutorials.

Run TraSig on example data and analyze outputs

The example inputs and outputs can be found under the folder example. You may follow the tutorial to run TraSig on the example data and analyze the outputs. You may also obtain the analysis outputs by running the aforementioned script analyze_outputs using command-line. See the tutorial for more details.

Prepare inputs

To run TraSig, we need to have 4 input files. Here is a tutorial, showing how to prepare these files from the inference results of any trajectory inference method included in dynverse. You can find the example expression data (input) and trajectory inference result (output) under the folder trajectory. You may also prepare the inputs for TraSig by running the aforementioned script prepare_inputs using command-line. See the tutorial for more details.

We can also accept inputs that are not generated by dynverse. For outputs from any pseudotime trajectory tool you prefer, you can prepare the inputs for TraSig following this tutorial.

We can also accept customized ligand-receptor database and customized gene list for alignment, if you would like to use the alignment option for TraSig. The inputs will be changed accordingly and you may need to specify the filepath and identifier for your own ligand-receptor database and gene list for alignment. Please find the corresponding arguements in the command-line tool and the corresponding variables in the tutorials mentioned above to make the changes. You may also find descriptions on the file formats in the tutorials. The example ligand-receptor database is from [1] and the example alignment gene lists is downloaded from the Seurat package.

Updates-log

  • 2-2-2022:
    -- Add support for conducting temporal alignment using customized gene list

  • 12-21-2021:
    -- Add support for conducting temporal alignment and calculating scores using optimally aligned expression profiles
    -- Add tutorial illustrating how to prepare inputs using user-defined trajectory, not necessarily from dynverse

Learn-more

Check our preprint at biorxiv.

Credits

The software is an implementation of the method TraSig, jointly developed by Dora Li, Jun Ding and Ziv Bar-Joseph from System Biology Group @ Carnegie Mellon University. We also acknowledge Jeremy J. Velazquez, Joshua Hislop and Mo R. Ebrahimkhani from University of Pittsburgh for the fruitful discussions on method development.

Contacts

  • dongshul at andrew.cmu.edu

License

This project is licensed under the MIT License - see the LICENSE file for details

References

[1] Ramilowski, J., Goldberg, T., Harshbarger, J. et al. A draft network of ligand–receptor-mediated multicellular signalling in human. Nat Commun 6, 7866 (2015). https://doi.org/10.1038/ncomms8866