The first OMIP panel to profile NK cells from tumour tissue

The History of NK cells in Immuno-oncology

NK cells (natural killer cells) have been a focus in immuno-oncology for decades, largely due to their ability to destroy tumour cells through spontaneous cytotoxicity, as well as their production of cytokines and chemokines that can help recruit additional immune cells.
 

More recent studies have shown that tumour progression and outcomes correlate with the presence of NK cells at the tumour site, making their study important from a therapeutic perspective.
 

Learn more about NK cells and their role in immuno-oncology.

The OMIP Panel Design

NK cells are notoriously difficult to study due to the limited amount of tissue that is normally available from tumour resections or biopsies.

This OMIP panel (Optimised Multicolour Immunophenotyping Panel) from Frutoso et al. takes a flow cytometry immunophenotyping approach in order to extract as much information as possible from a single-cell suspension with the goal of providing an in-depth characterisation of human NK cells.

Though other OMIP panels investigate these immune cells in a broader way (namely from human peripheral blood), this is the first specifically designed to profile NK cells isolated from tumour tissues.

Frutoso et al. combined collagenase Type II and DNase for tissue digestion in preparing the high-viability single-cell suspension, which yielded a good population of viable mucosal mononuclear cells when used with human mucosal tissues.

However, they found that detection of CD56, a biomarker typically used to identify NK cells, was affected substantially by the collagenase‐based tissue digestion. Thus, the panel is centred around the expression of NKp46, characterised as a highly conserved natural cytotoxicity receptor (NCR).

For the flow cytometry immunophenotyping, the team used a 27-colour phenotypic OMIP panel to identify NK cell activity and types. They compiled 18 biomarkers to assess NK cell function, including maturation, differentiation, migration, homing potential and functional state.

Learn more about flow cytometry panel design.

Performance of the OMIP Panel in Phenotyping NK cells

Even if it wasn’t in the original OMIP panel goal, most biomarker expressions in this OMIP panel could be assessed for CD3+ T cells to help provide greater biological insights.
 

The team concluded that this specific combination of biomarkers and the flow cytometry immunophenotyping approach provided a thorough characterisation of NK cells within tumour tissues and could prove to be a valuable tool in the study of immune cell function in human tours and mucosal tissues.
 

Read the full study to learn more about this 27-colour OMIP panel.

1.  Frutoso, M, Mair F, and Prlic M. OMIP‐070: NKp46‐Based 27‐Color Phenotyping to Define Natural Killer Cells Isolated From Human Tumor Tissues. Cytometry A. 2020 Oct; 97(10): 1052–1056. doi: 10.1002/cyto.a.24230. Epub 2020 Oct 8.