How Is a Vaccine Processed by the Body When It Is Given as a Shot?

In this short video, Dr. Stanley Plotkin explains how vaccines given as a shot are handled by the immune system.

Transcript

How Is a Vaccine Processed by the Body When It Is Given as a Shot?

I am Stanley Plotkin, Professor Emeritus of Pediatrics at the University of Pennsylvania.

So the task of a vaccine is to induce the same kind of immunity as the disease, but to do it in a manner that is safe. What happens when a vaccine is injected into the arm or given by mouth is that the substances in the vaccine, whether proteins or sugars, are taken up by cells, let’s say under the skin, and carried to a neighboring lymph node. In that lymph node, other cells pick up the proteins or sugars and transfer them to cells that can induce responses, for example in the blood stream, both in the serum and in the cells, that protect against the disease without causing the symptoms of the disease. So, the objective then of providing immunity is served by the injection taking the place of an infection that might happen throughout the body.

Related Centers and Programs: Vaccine Education Center

Last Reviewed on Jan 10, 2020