Diagnosing tuberculosis with cytokines IL-15, IL-10 and MCP-1, in addition to interferon-gamma

A pattern of two cytokines, called MCP-1 and IL-15, was reasonably good at differentiating between persons sick with TB and persons infected but not sick.

Monocyte chemotactic protein-1 (MCP-1) is a small cytokine belonging to the CC chemokine family. According to the new nomenclature, MCP-1 is called chemokine (C-C motif) ligand 2 (CCL2).

A third cytokine called IP-10 also showed promise at differentiating between people who are infected and those who are not.

Interferon gamma-induced protein 10 kDa (IP-10) is also known as C-X-C motif chemokine 10 (CXCL10). It belongs to the CXC chemokine family.

These 3 cytokines could form the basis of a new test to quickly detect whether tuberculosis is dormant or active and infectious.

52 chemokines from 4 families have been described. They interact with 20 receptors (click here for a larger image).

What is the difference between cytokine, interleukin and chemokine?

Cytokines (Greek cyto-, cell; and -kinos, movement) are substances secreted by cells of the immune system which carry signals locally between cells. They are proteins, peptides, or glycoproteins.

Interleukins are a group of cytokines first found to be expressed by white blood cells (leukocytes). The name is a misnomer since interleukins are produced by a wide variety of cells, not only leukocytes.

Chemokines (Greek -kinos, movement) are a family of small cytokines, or proteins secreted by cells. The name is derived from their ability to induce directed chemotaxis in nearby responsive cells; they are chemotactic cytokines.

References:
Immune system could be used to test for TB. Reuters.

Immunology Made Simple: "What are These People Talking About?"

Cytokines

Xpert MTB/RIF is a rapid diagnostic test for tuberculosis with high sensitivity (90%) and specificity (99%). Lancet, 2011.