VDJtools Analysis
Basic Usage
bash
# VDJtools requires Java java -jar vdjtools.jar <command> [options] # Or with wrapper script vdjtools <command> [options]
Calculate Diversity Metrics
bash
# Basic diversity (Shannon, Simpson, Chao1, etc.)
vdjtools CalcDiversityStats \
-m metadata.txt \
output_dir/
# Metadata format (tab-separated):
# #file.name sample.id condition
# sample1.txt S1 control
# sample2.txt S2 treated
Diversity Metrics Explained
| Metric | Description | Interpretation |
|---|---|---|
| Shannon | Entropy-based diversity | Higher = more diverse |
| Simpson | Probability two random clones differ | 0-1, higher = diverse |
| InverseSimpson | 1/Simpson | Effective number of clones |
| Chao1 | Richness estimator | Total estimated clonotypes |
| Gini | Inequality coefficient | 0=equal, 1=dominated by one |
| d50 | Clones comprising 50% of repertoire | Lower = more oligoclonal |
Sample Comparison
bash
# Find overlapping clonotypes
vdjtools OverlapPair \
-p sample1.txt sample2.txt \
output_dir/
# Calculate overlap for all pairs
vdjtools CalcPairwiseDistances \
-m metadata.txt \
-i aa \
output_dir/
# Overlap metrics: F2 (frequency-weighted Jaccard), Jaccard, MorisitaHorn
Spectratype Analysis
bash
# CDR3 length distribution (spectratype)
vdjtools CalcSpectratype \
-m metadata.txt \
output_dir/
# V/J gene usage
vdjtools CalcSegmentUsage \
-m metadata.txt \
output_dir/
Clonal Tracking
bash
# Track clones across timepoints
vdjtools TrackClonotypes \
-m metadata_timecourse.txt \
-x time \
output_dir/
# Identify public clones (shared across individuals)
vdjtools JoinSamples \
-m metadata.txt \
-p \
output_dir/
Input Format
VDJtools accepts MiXCR output or standard format:
code
# Required columns (tab-separated): count frequency CDR3nt CDR3aa V D J # Example: 1500 0.15 TGTGCCAGC... CASSF... TRBV5-1*01 TRBD2*01 TRBJ2-7*01
Convert from MiXCR
bash
# Convert MiXCR output to VDJtools format
vdjtools Convert \
-S mixcr \
mixcr_clones.txt \
output.txt
Parse VDJtools Output in Python
python
import pandas as pd
def load_diversity_stats(filepath):
'''Load VDJtools diversity statistics'''
df = pd.read_csv(filepath, sep='\t')
return df
def load_overlap_matrix(filepath):
'''Load pairwise overlap matrix'''
df = pd.read_csv(filepath, sep='\t', index_col=0)
return df
# Plot diversity across samples
def plot_diversity(stats_df, metric='shannon_wiener_index_mean'):
import matplotlib.pyplot as plt
plt.figure(figsize=(10, 6))
plt.bar(stats_df['sample_id'], stats_df[metric])
plt.xlabel('Sample')
plt.ylabel(metric)
plt.xticks(rotation=45)
plt.tight_layout()
plt.savefig('diversity_plot.png')
Related Skills
- •mixcr-analysis - Generate input clonotype tables
- •repertoire-visualization - Visualize VDJtools output
- •immcantation-analysis - BCR-specific phylogenetics