Detekcija rezistencijskih mutacija u regijama UL54 i UL97 ljudskog citomegalovirusa

master's thesis

• Title (english): Detection of resistance mutations in UL54 and UL97 regions of human cytomegalovirus
• Author: Antonela Mišković
• Mentor: Ivana Grgić (mentor)
• Mentor: Silvija Černi (sumentor)
• Committee member: Silvija Černi (predsjednik povjerenstva)
• Committee member: Maja Matulić (član povjerenstva)
• Committee member: Zlatko Liber (član povjerenstva)
• Committee member: Inga Urlić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2022-02-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Ljudski citomegalovirus je široko rasprostranjen herpesvirus koji uspostavlja latentnu infekciju u domaćinu.
Iako su infekcije uglavnom asimptomatske, u populaciji imunokompromitiranih osoba i novorođenčadi
mogu dovesti do komplikacija. Trenutno dostupnu antivirusnu terapiju čine ganciklovir, valganciklovir,
cidofovir i foskarnet koji djeluju na virusnu DNA polimerazu pri čemu se ganciklovir i valganciklovir
moraju prethodno aktivirati virusnom kinazom. Rezistencijske mutacije javljaju se unutar gena za ova dva
proteina (UL54 i UL97). Mutacije gena UL97 daju rezistenciju na ganciklovir i valganciklovir, dok mutacije
gena UL54 dodatno daju rezistenciju i na cidofovir i foskarnet. Cilj ovog istraživanja bilo je detektirati
rezistencijske mutacije u regijama UL97 i UL54 ljudskog citomegalovirusa izoliranog iz 14 uzoraka svakog
od dva ispitanika (novorođenče i transplantirani pacijent koji su primali različitu terapiju). Nakon
sekvenciranja regija UL54 i UL97 metodom po Sangeru, rezistencijske su mutacije analizirane u algoritmu
Mutation resistance analyzer. Kod transplantiranog ispitanika na imunosupresivnoj terapiji, čija je terapija
započeta ganciklovirom/valganciklovirom te je nastavljena foskarnetom, detektirane su rezistencijske
mutacije u obje regije. Kod novorođenčeta, liječenog ganciklovirom i valganciklovirom, nisu detektirane
rezistencijske mutacije Zaključeno je da su dulja podvrgnutost terapiji i dulji period uzorkovanja kod
transplantiranog ispitanika kao i naknadna terapija foskarnetom mogli pridonijeti razvoju rezistencije.

Abstract (english)

Human cytomegalovirus is a widespread herpesvirus that establishes a latent infection in the host. Although
infections are mostly asymptomatic, they can cause complications in the immunocompromised population
and newborns. Antiviral therapy includes ganciclovir, valganciclovir, cidofovir and foscarnet, which act on
viral DNA polymerase, where ganciclovir and valganciclovir must be pre-activated by viral kinase.
Resistance mutations occur within the genes for these two proteins (UL54 and UL97). UL97-mutations
confer ganciclovir/valganciclovir-resistance while UL54-mutations further confer cidofovir- and foscarnetresistance. The aim of this study was to detect resistance mutations in the UL97 and UL54 regions of isolated
human cytomegalovirus from 14 samples from each of the two patients (infant and transplant patient
receiving different therapies). After sequencing the UL54 and UL97 regions by the Sanger sequencing
method, resistance mutations were analyzed in the Mutation Resistance Analyzer algorithm. Resistance
mutations in both regions were detected in a transplant patient on immunosuppressive therapy whose
antiviral therapy was initiated with ganciclovir/valganciclovir and continued with foscarnet. No resistance
mutations were detected in infant treated with ganciclovir and valganciclovir. It was concluded that longer
exposure to therapy and longer sampling period in the transplant patient as well as subsequent foscarnet
therapy could contribute to the development of the resistance.

• Keywords: antivirusna terapija; ganciklovir; sekvenciranje; filogenetska analiza
• Keywords (english): antiviral therapy; ganciclovir; sequencing; phylogenetic analysis
• Language: croatian
• URN:NBN: urn:nbn:hr:217:224507
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra molekularne biologije (magistar/magistra molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-03-23 11:58:47