FOOD FORENSICS

Three Immunological Research Protocols for High School Biology Students

Developed by: Katherine L. Brown
© American Association of Immunologists 1999

Overview
Cytokine production in response to gram negative bacteria as part of the cell mediated immune response can be used to teach basic immunological concepts and research techniques to high school biology students. Cell mediated immune responses use T cells and effector cells, such as mononuclear phagocytes/macrophages, to rid the body of microbes, bacteria and viruses, some of which may live intracellulary. The communication among the involved cells is facilitated by the secretion of cytokines. Secretion of tumor necrosis factor, TNF, one of many known cytokines, mediates a natural immunity response and helps initiate the physiological response of inflammation, redness, swelling, fever, in response to infection, burns or trauma. If too little TNF is secreted, then infections may not be contained. In great amounts, the TNF enters the bloodstream causing fever and septic or endotoxin shock which can be fatal. In the study done by this teacher at the Infectious Disease Lab of Case Western Reserve University, THP-1 cells, a human macrophage line, were stimulated by bacterial liposaccharide (LPS) and Mycobacterium tuberculosis (MTB) to initiate secretion of TNF, tumor necrosis factor. The study used three immunological research protocols:

Activity I: cell counting using an exclusion dye trypan blue;
Activity II: a radioactive tag, tritated thymidine (³H-TDR), to study cell proliferation after stimulation;
Activity III: an ELISA to determine the concentration of TNF secreted in comparison to a known standard curve.

These three research techniques then were developed into activities and/or simulations for the high school biology student to learn about immunological research of cell mediated immunity.

Suggested Time
One week of 50 minute class periods.

Day One:
content lecture based upon background information

Day Two:
Activity I: cell count

Day Three:
Activity II: cell proliferation

Day Four:
Activity III: ELISA simulation

Day Five:
continuing the ELISA

Day Six:
assessment quiz

To receive a copy of this curriculum, please contact: The American Association of Immunologists, telephone: (301) 634-7178, fax: (301) 634-7887, email infoaai@aai.org.