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Host-Pathogen Interactions

A Magnificent Battle in an Evolutionary Arms Race


Kirsten L. Hokeness
Science and Technology Department
Bryant University
Stephanie Mott
Department of Science and Technology
Bryant University


This case study introduces students to the complex field of immunology and the wide variety of host-pathogen interactions that drive evolutionary change.  The case begins with a basic overview of the phases of the immune response and how each contributes to host defense against an invading pathogen.  In order to delve deeper into each phase, students explore the metaphor of a battle in which a host and pathogen are locked in combat in order to understand the individual components of the immune response.  Once students successfully understand how the immune system works in general, they are then asked to think creatively about how a pathogen that wants to survive could evolve to evade the immune response, and to find concrete examples in the literature.  The overall goal is for students to gain a deeper understanding of the immune response and how host-pathogen interactions drive coevolution of both host immune components and the pathogen itself. The case was originally designed for an introductory biology course, but can easily be adapted for use in a variety of different courses and levels.


  • Learn the basics about the innate and adaptive response.
  • Compare and contrast the innate and adaptive immune response.
  • Learn the functions of key cells in the immune system.
  • Explore the roles of antigens and antibodies in the context of an infection.
  • Comprehend what happens when parts of the immune system malfunction.
  • Identify key cytokines during an immune response.
  • Read and summarize primary literature.
  • Explain how pathogens can avert immune cell function.



Immunology; adaptive; host-pathogen interaction; viruses; pathogens; cellular biology; parasites; innate; evolution; bacteria; immune system

Topical Areas


Educational Level

High school, Undergraduate lower division, Undergraduate upper division



Type / Methods

Analysis (Issues), Directed, Journal Article



Subject Headings

Biology (General)  |   Cell Biology  |   Medicine (General)  |   Microbiology  |   Molecular Biology  |   Public Health  |  

Date Posted


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