|Marek Rabski, Andrzej M. Fal|
Macrophages are one of the most abundant cells of the immunologic system. They have ability to phagocyte, and present antigens to lymphocytes T, as well as to produce various proinflammatory cytokines and chemokines, what makes them important regulators of the inflammatory process. Various stimuli can activate signal transducting cascade leading to macrophage activation which results in diffrent cell function, depending on the Th1 or Th2 lymphocytes cytokines presence. It has been shown, that compared to healthy adults, in COPD patients percentage of airways macrophages is increased, especially in places of alveolar wall destruction in patients with emphysema, and it correlates positively with the disease severity. Many studies proved, that cigarette smoke induces secretion of proinflammatory cytokines e.g. TNF á, and also stimulates multicomponent NADPH oxydase which generates superoxide anions. Both mechanisms results in activation of the transcriptive factors NFęB i AP-1 which, in turn, switch on multiple proinflammatory genes. Increase in production of metalloproteinases and other proteolytic enzymes has also been observed. On the other hand, ability of macrophages to phagocytose apoptotic cells is impaired. According to the hygiene hypothesis, exposure early in life to the bacterial antigenes shifts immune system towards the Th1 lymphocyte response, thus protects individual from development of asthma. There are increasing evidence, that stimulating of macrophages with pathogen associated molecular patterns (PAMP’s) leads to inhibition of Th2 depended immune response and revert it to Th1-type response. Involving of macrophages in development and regulation of inflammatory processes in patients with obstructive airways diseases, makes them a promising target of modern therapies.
keywords: tma, POChP, makrofagi, proces zapalny, asthma, COPD, macrophages, inflammation
pages: from 23 to 31
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