الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
can originate from endothelial cells, platelets, leukocytes and erythrocytes but platelet-derived microparticles (PDMPs) are the most abundant accounting for approximately 70–90%.
The immune system refers to a collection of cells and proteins that function to protect the skin, respiratory passages, intestinal tract and other areas from foreign antigens, such as microbes (organisms such as bacteria, fungi, and parasites), viruses, cancer cells and toxins. The MPs play an active role in coagulation and intercellular communication and assist in activation or suppression of the immune system depending on their parental cell origin. Changes in the concentration and/or composition of circulating MPs have been described in various autoimmune diseases, including RA, SSc, MS, DM, ALP and SLE.
They display important biological properties that can mediate disease pathogenesis and provide important information of on-going pathogenic process.
While the etiology and clinical manifestations of autoimmune diseases may vary, the development of new therapies confronts many similar challenges especially in the setting of clinical trials. A particularly serious and vexing challenge relates to biomarkers. For most autoimmune diseases, studies on both patients and animal models have documented a host of phenotypic and functional immune cell abnormalities.
Summary & Conclusion
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Though a consensus protocol to measure MP does not yet exist, most studies showed markedly altered concentrations and distributions of MPs subpopulations in patients with rheumatic diseases. In addition, the impact of circulating MPs is not well understood. However, MPs mediated drug delivery system could prolong drug retention time, increase patient compliance as well as therapeutic effect.
Microparticles are newly recognized players in the pathogenesis of autoimmunity and therefore can serve as both biomarkers and targets of therapy.
Sustained therapeutic drug concentrations can also be achieved. The use of MPs as immune tolerogenic and as therapeutic agent has only recently initiated and is rapidly expanding. The design and safety of MPs will have to be addressed to achieve desirable outcome. The use of antigen-conjugated MPs appears to be therapeutically promising in experimental animal models.