Small-Volume Capillary Blood Immune Profiling by Single-Cell RNA Sequencing

Solution Overview

Problem

Current methods for immune profiling are limited by the need for large volume venous blood draws, which are invasive and costly, and do not allow for comprehensive studies of immune system dynamics over time due to the difficulty in obtaining repeated samples from individuals, particularly those with fragile veins.

Innovation Solution

A method using small volume capillary blood samples for single cell RNA sequencing (scRNA-seq) is developed, enabling the isolation of capillary peripheral blood mononuclear cells (cPBMCs) through gradient centrifugation, followed by sequencing and SNP analysis to generate profiles at different time points, allowing for the identification of diurnal and subject-specific genes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If large volume venous blood draws are used for immune profiling, then sufficient sample material is obtained for analysis, but the procedure becomes invasive and costly

Engineering Contradiction:

Improveblood sample volumeVSAvoidinvasiveness

Core Design Contradiction:

Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The invention extracts and isolates specific immune cells (PBMCs) from small volume capillary blood samples using density gradient centrifugation. This allows obtaining sufficient cellular material for comprehensive immune profiling from minimal blood volume (20-500 μL), eliminating the need for large volume venous draws while maintaining analytical adequacy

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The method employs single-cell RNA sequencing technology that can process small numbers of cells efficiently, treating each small blood sample as a disposable unit for comprehensive analysis. This approach makes immune profiling cost-effective and scalable without requiring expensive large-volume sample collection infrastructure

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

2Quantity of substance

If large volume venous blood draws are used for immune profiling, then sufficient sample material is obtained for analysis, but the procedure becomes costly

Engineering Contradiction:

Improveblood sample volumeVSAvoidcost

Core Design Contradiction:

Quantity of substanceVSEase of manufacture

Solution Approach 1:

The invention extracts and isolates specific immune cells (PBMCs) from small volume capillary blood samples using density gradient centrifugation. This allows obtaining sufficient cellular material for comprehensive immune profiling from minimal blood volume (20-500 μL), eliminating the need for large volume venous draws while maintaining analytical adequacy

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The method employs single-cell RNA sequencing technology that can process small numbers of cells efficiently, treating each small blood sample as a disposable unit for comprehensive analysis. This approach makes immune profiling cost-effective and scalable without requiring expensive large-volume sample collection infrastructure

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Loss of time

If repeated venous blood draws are obtained from individuals, then longitudinal immune system dynamics can be studied, but the procedure becomes difficult particularly for those with fragile veins

Engineering Contradiction:

Improvetime for repeated samplingVSAvoiddifficulty of sample collection

Core Design Contradiction:

Loss of timeVSEase of operation

Solution Approach 1:

The invention inverts the traditional approach by using capillary blood (from fingerstick or earlobe) instead of venous blood for immune profiling. This reversal enables easy repeated sampling from individuals including those with fragile veins, as capillary sampling is less invasive and can be performed multiple times without significant difficulty

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The invention extracts and isolates specific immune cells (PBMCs) from small volume capillary blood samples using density gradient centrifugation. This allows obtaining sufficient cellular material for comprehensive immune profiling from minimal blood volume (20-500 μL), eliminating the need for large volume venous draws while maintaining analytical adequacy

Inventive Principle:

Principle #2Taking out (Extraction)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach provides a cost-effective, non-invasive method for immune profiling that enables large-scale, high-resolution studies of immune state variation in health and disease across individuals, reducing the burden on patients and facilitating the understanding of temporal and inter-individual gene expression patterns.

Implementation Method 1

isolating capillary peripheral blood mononuclear cells (cPBMCs) from the diluted sample with gradient centrifugation

Methodology Applied

Scientific EffectGradient centrifugation: Centrifugal Separation

Data Source

PatentUS12454717B2Immune profiling using small volume blood samples

Publication Date: 2025.10.28 CALIFORNIA INST OF TECH

AI summary

The present disclosure provides methods, systems, devices, kits, and reagents for performing single cell sequencing (e.g., single cell RNA sequencing) from a low volume, capillary blood (or any low volume blood sample which is not obtained from a vein or by venipuncture).