In flow cytometry, what analytical outcome is primarily evaluated using scatter plots?

In flow cytometry, scatter plots are primarily utilized to evaluate cell population subsets. These plots allow for the visualization of two different parameters of cells, often forward scatter (FSC) and side scatter (SSC). Forward scatter correlates with the size of the cells, while side scatter provides information about the granularity or complexity of the cells. By examining the distribution of cells in these scatter plots, different populations or subsets can be identified based on their unique physical characteristics.

For instance, in immunological studies, different immune cell types (such as lymphocytes, monocytes, and granulocytes) can be differentiated from one another by their distinct positions on the scatter plot. This makes scatter plots an invaluable tool for analyzing heterogeneous cell populations and understanding their relative sizes and complexities, which is crucial in research and clinical diagnostics related to the immune response, diseases, and therapies.

The other options are distinct outcomes that typically require additional methods or analyses beyond what scatter plots alone can provide. Cell viability assesses whether cells are alive or dead, antibody affinity measures how well antibodies bind to their target, and cell differentiation involves understanding more complex changes in cell phenotype that often necessitate further techniques, such as additional staining or functional assays. Each of these aspects is important in immunology but