1.   You have to understand how cells interact.

2.   Evidence is accumulating to show that gut epithelial cells interact closely with adjacent mononuclear cells.

3.   In the brain, individual cells called neurons interact, sending and receiving messages to and from thousands of other neurons.

4.   The research is a breakthrough in understanding how nerve and brain cells interact, said Dr. Zach Hall, director of the National Institute of Neurological Disorders and Stroke.