April 6, 2016—(BRONX, NY)—A team of researchers at Einstein have created "maps" that colorfully illustrate the influence of the protein Rac2 in forming protrusions that allow mouse macrophages to migrate. The research is described in the April 15, 2016 print edition of The Journal of Immunology, whose cover image is taken from the study. The co-senior authors were Louis Hodgson, Ph.D., associate professor of anatomy & structural biology, and Dianne Cox, Ph.D., professor of anatomy & structural biology and of developmental & molecular biology. Both are members of the Gruss Lipper Biophotonics Center.

As seen in the upper image, computational analysis "maps" the motion (y axis) of a 50-micron cell-edge section of a mouse macrophage over 10 minutes (x axis). Cyclic edge motion is visible in which protrusions (red areas) alternate with retractions (blue areas). The lower image of the same macrophage shows that protrusive activity correlates with Rac2 activity using fluorescent biosensors that reveal when and where Rac2 is activated in the cell (red = high Rac2 activity, blue = low).

Additional authors were Bin Wu, Ph.D., and Ph.D. students Veronika Miskolci and Yasmin Moshfegh, all at Einstein.