Provost’s lecture series explores immune system

The human immune system protects against harmful microorganisms on a daily basis and has the ability to produce millions of pathogen-specific immune cells. Mark Jutila, a Bozeman native, is head of MSU’s department of microbiology and immunology and a major contributor to the body of knowledge on the immune system. Jutila delivered a lecture at the Museum of the Rockies on Feb. 16 as part of the Provost’s Distinguished Lecturer Series.

Jutila graduated from MSU in 1982 with a bachelor’s of science in microbiology. He received a Ph.D. from Washington State University and did a fellowship in the Department of Pathology at the Stanford School of Medicine. In 1989, he returned to MSU.

Jutila began his lecture by giving an overview of how the immune system works. The body fends off a wide array of microorganisms on a daily basis, many of which are highly pathogenic. “We have rather exquisite mechanisms to fight off viruses, bacteria, parasites and fungi,” Jutila said.

The immune system targets pathogens, or microorganisms that can harm the body, by targeting the molecules on pathogens called antigens. One example of a mechanism used to target pathogens is that the body makes antibodies. “Through some really wild mechanism those antibodies will eliminate, clear that pathogen from the body,” Jutila said.

Jutila explained that this process almost always works, and that the proportion of the time that the body cannot fight off the pathogen and becomes ill is actually very small. The antibodies the body makes last a long time, which explains why once the body is exposed to a pathogen it can become immune. Jutila said the key point in this is that antibodies are highly specific, “They target the molecules that are unique to the given pathogen.”

Jutila then explained that the body is capable of creating a defense for an impressive number of pathogens. “We have the capacity to make millions and millions of different antigen receptors each different by the antigen that they recognize,” he said.

Due to the number of antibodies the body is capable of creating, these antigens occur at a low frequency. How then can that specific antibody find its way to the correct pathogen when it enters the body? Jutila explained that this is due to the trafficking of the immune system. These cells are constantly moving through the body via the blood and lymphatic systems. Once a pathogen enters the body and the immune cell with the specific antigen receptor to protect against that pathogen recognizes that it needs to take action, the immune cell moves to a place where it can expand.

The lymph nodes and tonsils are places where immune cells proliferate, which explains why sickness is often accompanied by swollen lymph nodes and tonsils. The body is creating more immune cells. This is also why it takes a week to 10 days to get over things like a common cold. The body has to have time to mount its defense. Jutila also pointed out that the body creates antibodies before birth.

For the remainder of the lecture, Jutila discussed the work that came from his own studies. He emphasized the role of students and colleagues in the progress he was able to be a part of and humbly expressed, “This is not me.”

Part of Jutila’s research has focused on gamma-delta T-cells, which are a part of the body’s adaptive immune system response and the body’s immunity. His research into the body’s inflammatory response has helped in the development of treatments for disorders like psoriasis. Currently, Jutila’s research focuses on increasing the trafficking of immune cells in the body.

The lecture concluded with Provost Martha A. Potvin presenting Jutila with two awards recognizing his contributions to MSU.