Concepts
The Challenge: Isolated Metabolomics Studies
Metabolomics studies generate rich data about small molecules in biological samples. However, most studies exist as isolated datasets:
- Each study uses different experimental designs
- Sample groups and conditions vary across studies
- Raw data formats and processing methods differ
- Results are difficult to compare directly
This limits the potential for reuse and discovery across studies.
The Solution: Differential Profiles
integMET addresses this challenge by introducing the Differential Profile (DiffProf) as the fundamental unit of data.
What is a Differential Profile?
A Differential Profile captures how metabolites change between two biological conditions.
For example: - Disease vs. Control - Before treatment vs. After treatment - Mutant vs. Wild type - Stressed vs. Normal
Each DiffProf contains: - Two comparison groups (Group A vs. Group B) - Metabolite fold-changes between the groups - Statistical significance (p-values) for each change - Direction of change (up or down)
From Raw Data to Comparable Profiles
Traditional metabolomics produces a data matrix: rows of metabolites, columns of samples, cells containing abundance values.
integMET converts this into DiffProfs:
Traditional Data Matrix → Differential Profile
Sample1 Sample2 ... Group A vs Group B
Met1: 100 150 Met1: ratio=1.5, ↑
Met2: 200 80 Met2: ratio=0.4, ↓
... ...
By standardizing data into DiffProfs, integMET makes different studies comparable.
Why DiffProfs Enable Integration
1. Universal Comparison Unit
Every biological comparison — regardless of species, tissue, or experimental platform — becomes a DiffProf. This creates a common language for metabolomics data.
2. Focus on Biological Contrast
A DiffProf represents a biological event or contrast, not just raw measurements. This captures the biologically meaningful signal: what changes when conditions differ.
3. Cross-Study Discovery
With thousands of DiffProfs in a standardized format, you can:
- Find studies with similar metabolic signatures
- Discover unexpected connections between different biological phenomena
- Identify metabolites that consistently change across related conditions
Key Terminology
| Term | Definition |
|---|---|
| Study | A metabolomics experiment from a public repository (e.g., MetaboLights) |
| Differential Profile (DiffProf) | A standardized record of metabolite changes between two conditions |
| Metabolite | A small molecule tracked across studies and DiffProfs |
| iDMET | A similarity metric that quantifies how similar two DiffProfs are based on shared metabolite changes |
Next Steps
- Learn about the Data Model to understand how Studies, DiffProfs, and Metabolites relate
- Explore the Tutorial to see how DiffProf similarity networks work