Noble crayfish immune response to the crayfish plague disease agent and its analogues

master's thesis

• Title (croatian): Imunosni odgovor riječnog raka na uzročnika bolesti račje kuge i njegove analoge
• Author: Anita Tarandek
• Mentor: Kathrin Theissinger (mentor)
• Mentor: Sandra Hudina (komentor)
• Committee member: Sandra Hudina (predsjednik povjerenstva)
• Committee member: Ivana Maguire (član povjerenstva)
• Committee member: Jasna Lajtner (član povjerenstva)
• Committee member: Zoran Marčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2023-09-27, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Recently, immune memory in invertebrates has been demonstrated, revealing an improved
immune response to pathogen challenge after previous nonlethal exposures to the pathogen or
its analogues. However, this mechanism has been understudied in freshwater crayfish.
Therefore, in this study the effects of immune priming on the noble crayfish, Astacus astacus
were explored. Noble crayfish were primed with: i) crayfish saline solution, ii) beta-laminarin,
iii) inactivated Aphanomyces astaci hyphal suspensions and iv) inactivated A. astaci zoospores.
Then, the survival, and immediate and prolonged changes were monitored in the following
immunological parameters: total hemocyte count (THC), differential hemocyte count (DHC),
total protein content and gene expression of prophenoloxidase, immune system activator
C/EBP and immune system repressor Kr-h1. Hemolymph sampling was conducted 1, 4, 8, 24
hours and 16 days post-priming. Additionally, it was tested if priming could induce A. astaci
resistance as a long-term effect. The results indicate that immune priming has no effect on the
survival of the noble crayfish. Furthermore, the changes in the monitored immune parameters
of the noble crayfish are immediate and mostly return to normal values within 24 h. Finally,
results on the resistance to A. astaci remain inconclusive as no mortality due to infection was
observed.

Abstract (croatian)

Nedavno je imunosna memorija dokazana kod beskralježnjaka, otkrivajući poboljšani
imunosni odgovor na infekciju patogenom nakon prethodnih nesmrtonosnih izlaganja
patogenu ili njegovim analozima. Međutim, ovaj mehanizam nedovoljno je istražen kod
slatkovodnih rakova. Stoga su u ovom radu istraženi učinci imunosne pripreme na riječnog
raka, Astacus astacus. Riječni rakovi su pripremljeni s: i) puferom (engl. crayfish saline
solution, CBS), ii) beta-laminarinom, iii) inaktiviranom suspenzijom hifa Aphanomyces astaci
i iv) inaktiviranim zoosporama A. astaci. Potom su praćeni preživljenje te neposredne i
dugotrajne promjene sljedećih imunoloških parametara: ukupni broj hemocita (THC),
diferencijalni broj hemocita (DHC), ukupni sadržaj proteina i ekspresiju gena
profenoloksidaze, aktivatora imunosnog sustava C/EBP i represora imunosnog sustava Kr-h1.
Uzorkovanje hemolimfe provedeno je 1, 4, 8, 24 sata i 16 dana nakon pripreme. Osim toga,
testirano je može li priprema izazvati otpornost na A. astaci kao dugoročni učinak. Rezultati
pokazuju da imunosna priprema nema utjecaja na preživljavanje riječnih rakova. Nadalje,
promjene praćenih imunosnih parametara riječnog raka su trenutne i većinom se vraćaju na
normalne vrijednosti unutar 24 sata. Naposljetku, rezultati otpornosti na A. astaci ostaju
nerazriješeni budući da nije primijećena smrtnost zbog infekcije.

• Keywords: Astacus astacus; immune priming; Aphanomyces astaci; gene expression; innate immunity; resistance
• Keywords (croatian): Astacus astacus; imunosna priprema; Aphanomyces astaci; ekspresija gena; urođena imunost; otpornost
• Language: english
• URN:NBN: urn:nbn:hr:217:134246
• Study programme: Title: Experimental Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra eksperimentalne biologije (magistar/magistra eksperimentalne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2025-09-27
• Created on: 2023-10-16 10:58:59