Peripheral Blood Mononuclear Cells (PBMC) Single-Cell Sequencing

Peripheral Blood Mononuclear Cells (PBMC) are a highly heterogeneous group of cells found in human peripheral blood. Due to their convenient accessibility and rich information content, PBMCs have become an important window for studying the status of the human immune system, disease progression, and individualized treatment response. Traditional high-throughput sequencing technologies (such as bulk RNA-seq) can only obtain the average expression levels of cell populations, which can easily obscure differences between individual cells. In real biological systems, even cells that appear identical on the surface can have vastly different gene expression, metabolic states, and developmental trajectories. Single-cell sequencing of PBMCs breaks this 'average' limitation, allowing us to obtain molecular information such as the transcriptome, genome, epigenome, and proteome at the level of individual cells, ushering in an era where 'every cell is a unique research subject.' This technology is becoming a research hotspot in fields such as tumor immunology, infectious diseases, and autoimmune diseases.

 

I. Research Advantages of PBMC

1、Non-invasive Sample Source：Can be obtained through venipuncture without the need for tissue biopsy.

2、Highly Representative Immune Cell PopulationReflects dynamic changes in the immune system, suitable for longitudinal monitoring.

3、Suitable for Building 'Liquid Biopsy' Models：Can substitute for solid tissue samples in immune microenvironment analysis.

 

II. Breakthroughs Brought by Single-Cell Sequencing

Compared to traditional bulk RNA-seq technologies that can only reflect the average expression of cell populations and struggle to capture intercellular heterogeneity,Single-cell RNA Sequencing TechnologyCan perform transcriptome analysis on tens of thousands of PBMCs individually,thereby achieving:

1、Identification of Rare Cell Subpopulations (e.g., senescent T cells, inflammation-related monocytes)

2、Dynamic Tracking of Cell Lineages and Developmental Trajectories

3、Revealing Disease-Related Immune Imbalance Mechanisms

4、Discovery of New Immunotherapy Targets or Biomarkers

 

III. Technical Process of PBMC Single-Cell Sequencing

1、Sample Collection and PBMC Isolation

After collecting peripheral blood samples using anticoagulant tubes, PBMCs are commonly isolated via Ficoll density gradient centrifugation. The key is to maintain cell viability, avoiding activation or apoptosis.

2、Single-Cell Capture and Library Preparation

Current mainstream solutions include the 10x Genomics Chromium platform, whose microfluidic system enables high-throughput cell encapsulation and barcode labeling. Each cell is independently labeled and transcribed into cDNA, followed by library construction.

3、High-Throughput Sequencing and Data Processing

Using the Illumina platform for high-throughput sequencing, tools like Cell Ranger are then used for data quality control, UMI deduplication, cell clustering, and differential gene analysis.

4、Bioinformatics Analysis and Visualization

Further analysis tools such as Seurat and Scanpy can be used for annotation of PBMC subpopulations, trajectory inference, functional enrichment analysis, etc., laying the foundation for subsequent clinical correlation studies.

 

IV. Application Scenarios: The Value of PBMC Single-Cell Sequencing in Various Diseases

1、Tumor Immunology Research

PBMCs can reflect the systemic immune status of cancer patients, and single-cell sequencing can identify key subpopulations such as exhausted T cells and regulatory T cells (Tregs), providing new insights for predicting immunotherapy responses.

2、Autoimmune Diseases

In diseases like systemic lupus erythematosus (SLE), the single-cell map of PBMCs reveals mechanisms such as abnormal B cell activation and monocyte inflammatory phenotypes, providing a basis for screening new immunosuppressive targets.

3、Infection and Vaccine Response

During the COVID-19 pandemic, PBMC single-cell studies revealed differences in T cell responses between infected individuals and vaccine recipients, advancing precision vaccine design.

 

Currently, single-cell analysis of PBMC samples still faces challenges:Rapid Changes in Cell States: Requires quick processing and maintaining low temperatures;Cell Quantity Limits Analysis Depth: Rare subpopulations may be overlooked;High Data Analysis Threshold: Relies on integrating multiple algorithms and high-performance computing. At Betta Pharma, westrictly control the preprocessing flow, optimize cell capture strategies, and provide one-on-one bioinformatics analysis servicesto maximize data quality and interpretation efficiency, helping research clients efficiently advance PBMC-related projects.