Provided herein are methods of evaluating efficacy of a treatment in a subject having eye inflammation (e.g., a subject having dry eye syndrome) and selecting a subject for participation in a clinical study. Also provided are methods of treating a subject having eye inflammation (e.g., a subject having dry eye syndrome).

The disclosure provides noninvasive methods for the in vivo identification and characterization of various immune cell populations in human skin. The methods of the disclosure employ advanced imaging systems based on nonlinear optical microscopy to generate images that are analyzed to detect, identify, differentiate, and quantify immune cell populations in human skin by their morphological, metabolic and behavioral signatures.