Microscopic Battlefield: Watch as a Killer T Cell Attacks a Cancer Cell

Every day, inside our body, there is a war going on. Micro­scop­ic invaders of one kind or anoth­er try to make a meal of us, and our immune sys­tem fights back, seek­ing out the invaders and destroy­ing them. One of our body’s most impor­tant foot-sol­diers in this war is the T cell, a type of white blood cell with recep­tors that can rec­og­nize for­eign sub­stances. Like all white blood cells, T cells orig­i­nate in the bone mar­row, but then they migrate to an organ called the thy­mus (hence the “T” in “T cell”), where they evolve into spe­cial­ized immune sys­tem war­riors. Mature T cells, which leave the thy­mus and cir­cu­late around the body, come in dif­fer­ent types. One type, the cyto­tox­ic T cell, spe­cial­izes in attack­ing and killing cells of the body that are infect­ed by virus­es, bac­te­ria, or can­cer.

Which is where this fas­ci­nat­ing lit­tle video comes in. It shows a cyto­tox­ic T cell (also known as a “killer T cell”) attack­ing a can­cer­ous cell. The process is shown at 92 times the actu­al speed. And for a sense of scale, a cyto­tox­ic T cell is only 10 microns long, or about one-tenth the width of a human hair. The video was cre­at­ed by PhD stu­dent Alex Rit­ter at the Uni­ver­si­ty of Cam­bridge, and post­ed recent­ly in the uni­ver­si­ty’s “Under the Micro­scope” Web series. Rit­ter’s super­vi­sor in the Depart­ment of Med­i­cine, Pro­fes­sor Gillian Grif­fiths, explains the impor­tance of the research asso­ci­at­ed with the video:

Cyto­tox­ic T cells are very pre­cise and effi­cient killers. They are able to destroy infect­ed or can­cer­ous cells, with­out destroy­ing healthy cells sur­round­ing them.…By under­stand­ing how this works, we can devel­op ways to con­trol killer cells. This will allow us to find ways to improve can­cer ther­a­pies, and ame­lio­rate autoim­mune dis­eases caused when killer cells run amok and attack healthy cells in our bod­ies.

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