An endocrinology laboratory exercise demonstrating the effect of confinement stress on the immune system of mice

This article describes a simple laboratory exercise for examining the effect of stress on the immune system in mice. Mice are subjected to confinement stress for 1 h, after which a sample of blood is collected via the caudal vein. Blood samples are smeared onto microscope slides, air dried, and stained with Wright's Giemsa stain. When differential white blood cell counts are performed, there are noticeable differences between the neutrophil and lymphocyte counts of stressed versus control mice. The protocol is simple enough for students to perform, and the entire experiment can be completed within 3 h. Examples of ways in which the basic protocol can be modified to accommodate a shorter laboratory class are provided. This hands-on laboratory experiment provides students with experience using the scientific method to investigate the interaction between the endocrine and immune systems in response to stress.