Which two properties are used initially in gating during flow cytometry analysis?

In flow cytometry analysis, the initial gating process relies on forward scatter and side scatter properties of the particles being analyzed. Forward scatter is typically associated with the size of the particles; larger particles will scatter more light in the forward direction. Side scatter, on the other hand, provides information on the granularity or internal complexity of the particles, including aspects such as cell density and structure.

By utilizing these two properties, analysts can effectively create a preliminary gate to isolate populations of interest before further analysis with fluorescent markers. This initial gating is crucial as it allows for the identification of distinct populations within a heterogeneous sample, simplifying the analysis of more complex flow cytometry data.

Other options, while relevant to different aspects of flow cytometry, do not serve as the primary means of initial gating. Fluorescent intensity and wavelength pertain to the detection of specific markers on the cell surfaces, while size and color or shape and density are not standardly used in the initial gating strategy in flow cytometry protocols. Thus, forward and side scatter remain the fundamental parameters for setting up gates based on particle characteristics.