A six-color flow cytometric assay for the analysis of peripheral blood dendritic cells
Stefania Giannelli1, Adriano Taddeo, Pietro Presicce
1Laboratory of Immunology, Dipartimento di Scienze e Tecnologie Biomediche, Universita Degli Studi di Milano, Milan, Italy.
Insights
A new 6-color flow cytometry assay accurately counts myeloid (mDCs) and plasmacytoid (pDCs) dendritic cells. This advanced method reveals distinct activation marker expression differences between these crucial immune cell subsets.
Area of Science:
- Immunology
- Cell Biology
- Biotechnology
Background:
- Flow cytometric analysis of peripheral blood dendritic cells (PBDCs) is clinically relevant.
- Current 3- or 4-color assays limit multiparametric analysis of dendritic cell (DC) subsets due to a lack of unique lineage markers.
- A novel 6-color assay was developed to overcome these limitations.
Purpose of the Study:
- To develop and validate a dedicated 6-color flow cytometry assay for analyzing myeloid (mDCs) and plasmacytoid (pDCs) dendritic cell subsets.
- To enable multiparametric analysis of DC subsets, including their activation and maturation markers.
- To compare the performance of the 6-color assay with existing 3-color methods.
Main Methods:
- A single-platform 6-color flow cytometry assay was utilized.
- Whole-blood samples from 20 healthy controls were stained with specific antibody combinations targeting DC markers and activation/maturation markers.
- A parallel dual-platform 3-color assay was used for comparative analysis.
Main Results:
- The 6-color assay yielded cell counts for mDCs and pDCs comparable to the 3-color assay.
- Only the 6-color assay demonstrated differential expression of activation markers between mDCs and pDCs.
- Specifically, pDCs showed lower levels of costimulatory molecules and HLA-DR, but higher levels of CD83 compared to mDCs.
Conclusions:
- The developed 6-color assay is a sensitive tool for evaluating variations in the number and characteristics of mDCs and pDCs.
- This assay facilitates a more detailed understanding of the immune response orchestration.
- Assessing the balance between mDCs and pDCs is critical for immunological insights.
Background:
Flow cytometric analysis of peripheral blood dendritic cells (PBDCs) and their myeloid (mDCs) and plasmacytoid (pDCs) subsets is a less invasive procedure that is acquiring growing clinical relevance. Because dendritic cells (DCs) lack unique lineage markers, current methods that are based on 3- or 4-color assays do not allow multiparametric analysis of DC subsets. In this study a dedicated 6-color assay was developed.
Methods:
mDCs and pDCs were counted and characterized for the expression of activation/maturation markers by using a single-platform 6-color assay. Whole-blood samples from 20 healthy controls were directly stained with either CD80-FITC/CD40-PE/lineage-PerCP-Cy5.5/CD123-PE-Cy7/CD11c-APC/HLA-DR-APC-Cy7 or CD86-FITC/CD83-PE/lineage-PerCP-Cy5.5/CD123-PE-Cy7/CD11c-APC/HLA-DR-APC-Cy7 combination, in the presence of commercial fluorospheres. A dual-platform 3-color assay currently in use was run in parallel for comparison.
Results:
The 6-color assay provided mDCs and pDCs counts similar to counts obtained by the 3-color assay. Only the 6-color assay could show differential expression of activation markers by mDCs and pDCs, with pDCs expressing lower levels of costimulatory molecules and HLA-DR, but higher levels of CD83.
Conclusions:
The 6-color assay described here may be a sensitive tool for assessing possible variations in the number and features of mDCs and pDCs whose reciprocal balance is critical in understanding the more detailed orchestration of immune responses.
