Platelet activating factor
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The point from this chart is that this one mediator has a wide range of biological effects. This is true of many mediators, e.g., interferon-gamma, interleukin-1, and tumor necrosis factor-alpha. In addition, mediators like PAF synergize with other mediators to accentuate the biological effects of those other mediators. You will also recognize that many of the proinflammatory effects that PAF has are shared by other, entirely different mediators. This is evidence of the redundancy that characterizes, not only the systems of the space shuttle, but also cytokine networks.