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The immune cycle is a term that describes the natural homeostatic oscillation of the immune system when chronic inflammation is occurring. A bit like the menstrual cycle, the exact periodicity (wavelength) and waveform of each particular individual patient is different.〔 That is, different people have different immune cycles. However, the immune cycle repeats itself approximately every 7-days on average.〔 It was initially found by taking C-reactive protein levels in the blood every few days so that enough time points could show a repeating fluctuation (a wave-like cycle).〔〔(【引用サイトリンク】title=A Matter Of Time - Australasian Science Magazine )〕 This is caused by the synchronous division of T cells over time, with T-effector cells boosting immune activity followed by T-receptor cells suppressing the immune response.〔 Although the exact reason for the immune cycle is not yet clear, it appears to be a result of repeating, alternating stimulation and inhibition of the immune response, which has been proved in cancer patients.〔 Many cycles occur in the body - like temperature regulation and hormone levels - and the exact cause for these cycles is also unknown, but it is thought to involve the hypothalamus. ==Discovery== The idea of an immune cycle has existed for many years. In 1891, Dr William Coley noticed that some of his patients responded better to treatment than other patients, even with complete responses.〔 Almost a century later, in 1975, physicist George Irving Bell developed a mathematical equation to predict a hypothetical immune cycle. Dr Robert North, writing in the 1980s, demonstrated that chemotherapy encouraged the growth of tumors in mice, whose immune systems are very similar to humans.〔Ibid.〕 Unfortunately, these pioneers were unable to prove its existence, particularly since the necessary technology did not yet exist.〔 In the late 1990s, Associate Professor Brendon Coventry noticed that some of his patients responded better to a Melanoma vaccine better than other patients despite receiving identical treatment.〔http://www.theaustralian.com.au/national-affairs/budget-2015/budget-grants-regime-ignores-innovation-cancer-pioneer/story-fntfbo9p-1227358206121〕 When local cancer tumours where injected with the vaccine, cancers that had not been injected began to shrink as well, thus indicating an immunogenic relationship.〔http://www.surgeons.org/media/21677517/ASC-Media-Release-Unexpected-Benefits-Observed-in-Cancer-Treatments.pdf〕 These observations led him to speculate that the immune system operates in a cyclical manner, with peaks and troughs.〔 Operating on this theory, Coventry was able to increase complete response rates to treatment of advanced melanoma from 7% to 17% and without noticeable negative side effects to chemotherapy and radiotherapy.〔(【引用サイトリンク】title=AM - Melanoma vaccine increases survival rate 17/04/2014 )〕〔(【引用サイトリンク】title=Melanoma vaccine giving cancer victims hope )〕 In 2004, Associate Professor Manfred W. Beilharz et al. from the University of Western Australia began reporting on similar patterns in the treatment of HIV/AIDS infected mice.〔Manfred W. Beilharz et al. “Timed Ablation of Regulatory CD4+ T Cells Can Prevent Murine AIDS Progression,” The Journal of Immunology 172 (2004)〕 The 2009 publication of "CRP identifies homeostatic immune oscillations in cancer patients: a potential treatment targeting tool?" in the Journal of Translational Medicine, of which Coventry was the lead author, signalled the first time the immune cycle had been proven to exist.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Immune cycle」の詳細全文を読む スポンサード リンク
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