Molloy College 1 article published in JoVE Immunology and Infection Mesenchymal Stem Cell Regulation of Macrophage Phagocytosis; Quantitation and Imaging Jodi F. Evans1, Anthony E. Ricigliano1, Anthony V. Morante1, Emily Martinez1, Darlisy Vargas1, Jonah Thyagaraj1 1Molloy College Presented here is a protocol to quantify and produce dynamic images of mesenchymal stem cell (MSC) mediated regulation of macrophage (MΦ) phagocytosis of non-opsonized yeast (zymosan) particles that are conjugated to a pH-sensitive fluorescent molecule.