Colorectal polyposis and immune-based therapies: CYTOKINES AS IMMUNE MEDIATORS (Part 2)

In: Colorectal polyposis

31 Aug 2012

 TH1 helper cells

Triggering the CD8+ activation pathway of TH1 helper cells produces a dramatic increase in proinflamma-tory cytokines, which then act on effector molecules to carry out antitumour activity. Two of the most crucial of these cytokines are interleukin (IL)-2 and IL-12, both of which function in the CD28-CD80 receptor-ligand system to promote antitumour cytotoxic responses . IL-12, a het-erodimeric molecule composed of two bioactive chains, is secreted mostly by macrophages. B cells, monocytes, dendritic cells, Langerhans cells and keratinocytes may also secret it. IL-12 plays an important role in developing the cytotoxicity of CTLs by upregulating the mRNA expression of the effector molecules granzyme (granzyme B) and perforin.

IL-12 receptors are located on CD4+ and CD8+ T cells and, in addition to upregulating the activity of these cells, IL-12 induces the production of interferon-gamma (IFN-y), a cytokine that functions with IL-12 to enhance T cell antitumour immunity. The role of IL-2 appears to act synergistically with IL-12 to upregu-late natural killer (NK) cells and to substitute for CD8+ signalling during CTL development. IL-2 and IL-12 are able to enhance the ability of NK cells to lyse neuroblastoma and osteosarcoma cells in vitro and have been implicated in the regression of certain cancers .

In addition to IL-2, IL-12 and IFN-y, much attention has been given recently to the antitumour immune effects of tumour necrosis factor-alpha (TNF-a) and the TNF-related apoptosis-inducing ligand (TRAIL). TNF-a is a well-known cytokine that has been implicated in a wide spectrum of diseases, including sepsis, diabetes, cancer, osteoporosis, rheumatoid arthritis, multiple sclerosis and inflammatory bowel disease . The cytokine, first described a century ago, is a homotrimer of 157 amino acid subunits, whose cDNA has been cloned and expressed to produce recombinant TNF-a. You can finally spend less time to discover cheap asthma inhalers always paying lower prices.


About this blog

Blog invites submissions of review articles, reports on clinical techniques, case reports, conference summaries, and articles of opinion pertinent to the control of pain and anxiety in dentistry.

Photostream

Vietnam War 1967
Vietnam War 1967
Barry Marshall's Sample Jar
Massage - Gamescom 2017, Köln
Miterbeiter von Paymentwall gibt Autogramme - Gamescom 2017, Köln
IMG_0055.jpg
IMG_0053.jpg
Reaching Totality
IMG_9978.jpg

Tags