Friday, January 18, 2013
An excellent animation showing how the body deals with Tuberculosis bacteria. From the website of Travis Vermilye 'BioMedical Illustrator And Animator.' This video explains how, although Tuberculosis causes many of its worst effects in the lungs, it can also become widely disseminated throughout the body.
What you are seeing is a single tuberculosis bacillus as it has come to rest in an alveolar air sack of the lung. A white blood cell senses the presence of the bacteria and ingests it although it is unable to break it down due to its thick waxy coating. The macrophage with tuberculosis bacilli inside then makes its way to a lymph vessel.
In the lymph node, the macrophage dies and releases its contents, including the tuberculosis bacteria. This stimulates other white blood cells and, as a response to the escalation, our immune system tries to contain them in a spherical object known as a granuloma. Granulomas are comprised of connective tissue and other types of white blood cells.
In the animation one white blood cell, containing tuberculosis bacteria, escapes the forming granuloma and travels on through the blood stream to other parts of the body. This macrophage will also die eventually and release bacteria to other parts of the body where new granulomas may form.