I. SUMMARY lnvertebratesare widely distrbuted animals.They can be found in almostany krnd ofhabitat. Their successfulsurvival shategiesare basedon short life span combinedwith numerousoffspring and, more importantly,all invertebratespecieshavedevelopeda wriety ofdefensemechanismselficientlyrecognizingand respondingto non-selfsubstances. The defensemechadsmsof earthwoms were studiedover the pastfou decades.It becameappdent thattheearthworms.aswell asotherinvertebrates,lackspecificimmunoglobulins,lymphoc)4esor otherfeatures ofthe adaptiveimmunesystemdescribedin verteblates,but possessirmatedefensecomponents In this thesis,we foousedon the detaildescriptionof somedefensemoleculesinvolvedin imate immunityof earthworms. l. Lysozyme is an erzyme with strong antibacterialactivity describedin many organisms. We characterizedthelysozymeof Erieniaandrei(formerly E.fetida andrei)earthwormbothstruchmlly and functionally.Moleoularcharactefiationof lyso4rne providesa new tool for monitoringof innateimmunity in earthworms. 2. A cltol''tic effect of the coelomicfluid of E. fetida was observedin experimentswith TNF-sensitive tumorL929 cell line. Subsequentisolationof l)tic proteinsled to theidentificationof 42-kDaprotein,which wasnamedcoelomiccytolyticfactor- CCF.CCFwasshom to bepresentalsoin coelomicfluid of mother..
