Transmissible Murine Colonic Hyperplasia

Abstract

. After ex pos ure to a varian t of Citro bacter [reundii , suckling and adult mice developed transmissible murine coloni c hyper plasia of the same degree of seve rity . Muco sal hyperpl asia was most severe 2 to 3 weeks after inocu lation and then regressed . Suckling mice had a high morta lity because of seconda ry infla mmat ory and erosive changes . Severe hyper plasia was char acterized by mitotic activity along the ent ire crypt column and surface mucosa .Tra nsmissible m uri ne colo nic hyperplasia is a nat ura lly o ccu rr ing infectious di se ase of mi ce , cha ra cte rize d b y mu co sal hyp e rpl asia of th e d ista l col on . Erosio n a nd inf la m ma tio n ma y ac co m pa ny t he hyp e rpl asia. It is ca use d by a varia nt of Citrobacter [reundii [ I I. In a na tural o u tb re a k ret arded g ro wth , ruffle d fur , soft feces , o ccasio na l rect al pr ol a pse a nd mod erat e mort ality were see n in mic e a t th e lat e s uc kling a nd ea rly we an ling ag es. T he se signs we re se e n rarel y in a d u lts [3].T he ac tua l incid ence of tr an smi ssibl e mu rin e col on ic hyp erpl a sia in mouse co lo nies is difficult to d e termin e , since th e ine xp erien ced o bserve r ma y not not e the vag ue cl in ical signs a nd fre q uent lac k o f o bv io us gross le sion s . A num b e r o f po ssibl y rel at ed synd ro mes of mic e ha ve be en de scri be d b y o t he r la bo ra tories .T wo o f th ese la b orat orie s isol at e d varia nt s of C. fre undii a nd rep ro duce d co lo nic hyp e rpl a sia in experi me nt a lly in o cul a te d mic e [2 , 5 , 6 ]. T he pat ho lo gy de scribe d in th e se re po rts parti all y re sembl ed th at for tr an smissibl e murin e colonic hyp e rpl asia , b ut th ere a re diffe re nc es th at m ak e it di fficult to sta te t he y a re a ll th e sa me di se a se p roce ss . T hese d iffe re nces ma y be re al o r ma y b e ca use d b y vari at io n in co nd it io ns a nd tim e o f sa m p ling . T he ag es of mi ce a nd histo gen e sis o f th e lesion s were not given in re po rt s of ei t her the natu ral o r exp e rime n ta l di se ase . Ot he r possibl y rel at ed le sion s , of un d et e rmin ed ca us e , have bee n d escribe d [3 , 11] . T hese we re cl assi fied as co litis cystica [3 ] a nd ne opl asia [11] a n d had down growth of mu co sal e pi the lium into t he s u b m ucosa . E p ithe lia l d o wn gro wth ha s not bee n see n in tran smi ssible murin e col onic hyp erplasia o r o t he r hyp erpla st ic di se a se s kn o wn to be associa te d wit h C. freu ndii.Ou r stu dy exa mi ne s the path o gen e sis o f t his di se ase in N I H Sw iss m ice a nd co m pa res le sion s to th o se found by oth ers . Becau se of report ed clinical di fferences 223

IκBNS Regulates Murine Th17 Differentiation during Gut Inflammation and Infection

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In Vitro and In Vivo Model Systems for Studying Enteropathogenic Escherichia coli Infections

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Identification and characterization of Cri1, a locus controlling mortality during Citrobacter rodentium infection in mice

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