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Abstract 1\·Ia$rcells :ll” f011J1d resident ill 11$$\’ ~lHOll£1”Olll till’ body, P:l,~iC’11:lrly ill association with structures such as blood vessels and nerves, and in proximity 10 surfaces rhat imedilce ihe external environment. M I cells are bone manow-derived lind particulady depelld upon srem cell fuclor (SCF) for their urvival. Mast cells appear 10’be highly engineered cells with multiple critical biological functious. They may he activated by a mnnber of stimuli lila I are both (Fc,aU)( high affinity receptor 011 the tllface of masr cells) dependent and -cdU) independent. Aerivation through variou receptors leads to distinct signaling paihways. After activation, IlliISI cells may immediately extrude granule-ass eated mediators and aenerare lipid-derived substllilCes that induce munediste allergic iuflauanatiou, Mast cell activation may also 00 followed by the synthesis of chemokine and cytokine . Cytokine and chemokiue secretion. which occurs liOlU:Slater. may contribute to chronic inflammation ()ll’tcalfe et at., 1997). MS$( cells can be divided iLIl”Qtwo nbrypes b sed on diffe rences in tbeir ne ~lfnd serine protease content, tlJe Mer phenotype containing only tryptase aud the Mer phenotype containing bod .• rryptase and ehym e«(lraDi e/ al., 1986 cheehrer et al; 1990). Biological filllctiol.lS of mast cells appear to include a role in innate U11l.1.11Ulity, involvement ill host defense mechanisms against parasitic infestations inunuuomodulari II of the innnune system. and tissue repair and augiogelle5i$(.Metclltfe el at.; 1997). 1ast cells have been implicated in the pathogene is of allergic. diseases and iu ill flanunarory responses associated with parhological immune and disease-re lated processe including fibrosis, autoimmune pathology. and lleoplasia(T :’1)’101” :mll )lelcl1lre, :WOl). Azoospeunia, is defined as complete absence of penn from the ejllclIlale(\Villol, .9’82). Azoospermia is common among the infertile population. It cccu i~l to-20 of men round 10 have ablloll.llal semen analysis(S •.m.•well-Smith llDd Hendry, ·t984). PDF created with pdfFactory Pro trial version www.pdffactorv.com |