الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Heat shock proteins (Hsps) have been shown to be the most phylogenetically conserved proteins present in all prokaryotes and eukaryotes. Hsps were described since 1964 when it was noted that there was changes in polytene chromosome in Drosophila buskii. Later on, their gene product had been identified. Hsps induction was limited to the fly till 1978 when analogous response had been developed in avian and mammalian tissue culture cells. Hsps were defined that their synthesis is stimulated by environmental stress through which there is a change in temperature few centegrades above normal and their genes contains a conserved sequence of base pair. Hsps were classified according their molecular weight in kilo Dalton into four major families (Hsps60, Hsps70, Hsps90 and small Hsps). And also, there are several Hsps had been identified e.g.Hsp110, Hsp10, Hsp27, Hsp40, Hsp73, Hsp65, Grp96 and Grp78. There are many several factors which induce Hsps release; 1-physical factors: such as high temperature, noise, ultra violet light and radiations. 2-Chemical factors: including xenobiotics such as; carbon monoxide, heavy metal and dust. 3-Biological factors: such as; infection by bacteria, parasites and fungi. Traditionally Hsps were regarded as intracellular molecules; later on there has been intense interest in their extracellular functions. Hsps synthesis is regulated at several levels. Mainly regulated at transcriptional level via activation of one or more of heat shock transcriptional factors (HSFs) that bind to DNA at a specific sites of Hsps gene promoter region called heat shock element (HSE). Also there is translational regulation of Hsps synthesis in higher eukaryotes. Major Hsp70 genes were located between complement and TNF genes. Hsps can be identified by monoclonal antibody assay which include immune blotting, SDS PAGE, indirect immunelectrophoresis, also Hsps can be identified by Immunohistochemical methods. Hsps have several functions; The main function of Hsps being as a molecular chaperone the concept which was discovered by Ellis in 1987 through which they recognize and bind to nascent polypeptide and partially folded intermediates preventing their aggregation and misfolding. Besides molecular chaperone function, Hsps have been incriminated in innate and adaptive immune response and various autoimmune diseases.The first anti-Hsps antibodies discovered is to Hsp27, Hsp60, Hsp70, and Hsp90 in plasma of workers in steel industry. Also there is increased frequency of anti-Hsp70 in workers exposed to dust, heat and noise. Hsps mainly Hsp60, Hsp70 are highly immunogenic; they are capable of inducing antibodies besides T cell activation via cross reactivity for α β T and γ σ T cells from the sites of inflammations. It could be concluded that • Hsps act as a molecular chaperone and are produced during cell stress • Hsps are important in immune response as they are involved in innate and adaptive immune response. • They play a role in antigen presentation and cytokine production. • They are associated with a variety of diseases including autoimmune diseases , infections and cancers. • They are also associated with transplantation immunology ,and immunotherapy as vaccination against cancers and infectious diseases.