Primerjava in genetska opredelitev dveh sevov virusa Zika

Smlatić, Nuša (author), Avšič Županc, Tatjana (mentor), Korva, Miša (co-mentor)

Virus Zika uvrščamo v družino Flaviviridae ter med viruse, ki jih prenašajo členonožci. Ljudje se z virusom okužijo z vbodom okuženih komarjev iz rodu Aedes, virus se lahko med nosečnostjo ali porodom prenese tudi iz okužene matere na otroka. Večina okužb z virusom Zika poteka brez kliničnih znakov bolezni, lahko pa pride do resnejših nevroloških zapletov, kot sta sindrom Guillain-Barré in mikrocefalija pri novorojenčkih. Virus izvira iz vzhodne Afrike, nato se je razširil v dve smeri, v zahodno Afriko in nato v Azijo. Tako sta se pojavili dve genetski liniji; Afriška linija in Azijska linija. V magistrskem delu smo primerjali dva seva virusa Zika: sev #976, ki je bil izoliran leta 1947 iz vzorca krvi opice iz Ugande in sev 800/16, ki so ga izolirali maja 2016 iz seruma viremične bolnice, ki se je vrnila iz Brazilije in je kazala značilne klinične znake okužbe z virusom Zika. Ugotovili smo, da so za gojenje preiskovanih virusnih sevov primerne celične linije iz opičjih ledvičnih epitelijskih celic VERO E6, celična linija iz komarjevih celic C6/36 in celična linija iz celic človeškega neuroblastoma SK-N-SH. Virusna seva sta povzročila CPU na celični liniji VERO E6 in SK-N-SH, ne pa na celični liniji C6/36. Določili smo nukleotidno in aminokislinsko zaporedje celotnih genomov. Ugotovili smo, da je virus Zika, sev #976, eden od izolatov tipskega seva virusa Zika MR766, ki so jih izolirali leta 1947 v Ugandi in sodi v Afriško linijo ZIKV. Sev 800/16 spada v Azijsko linijo in je zelo podoben sevom, ki so v letih 2015 in 2016 povzročili epidemijo v Južni in Srednji Ameriki ter na Karibih.

• Language: Slovenian
• Keywords: virusi, Flavivirusi, virus Zika, klinični vzorci, molekularne metode, nukleotidna zaporedja, sekveniranje, filogenetska analiza, genetska raznolikost
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [N. Smlatić]
• Year: 2017
• PID: 20.500.12556/RUL-94426
• UDC: 578.7:578.833.2:57.083.2
• COBISS.SI-ID: 4819832
• Publication date in RUL: 24.08.2017

Secondary language

• Language: English
• Title: Comparison and genetic characterization of two Zika virus isolates

Abstract

Zika virus is an arthropod-borne virus and belongs to the Flaviviridae family. The virus is primarily transmitted through the bite of infected Aedes mosquitoes, but can additionally be transmitted from mother to child during pregnancy or around the time of birth. Although most Zika virus infections are subclinical, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in newborns. The virus have originated in East Africa and subsequently spread in two directions - to West Africa and then to Asia. There are two genetic lineages of Zika virus, the African lineage and the Asian lineage. In this master’s thesis we compared two strains of the Zika virus: strain #976 that was isolated in 1947 from the blood sample of a monkey in Uganda, and strain 800/16 that was isolated in 2016 from the serum of a viraemic female patient who returned from Brazil and presented typical clinical symptoms of an infection with the Zika virus. We established that the cell line of a monkey kidney epithelial cells VERO E6, the cell line of a mosquito cells C6/36 and the cell line from the cells of a human neuroblastoma SK-N-SH support the growth of the studied virus isolates. The viral isolates caused a CPU on the cell lines VERO E6 and SK-N-SH, but not on the cell line C6/36. We also defined the nucleotide and amino-acid sequence of the complete genomes. We found out that Zika virus, strain #976, is one of the isolates of the prototype strain ZIKV MR766, that were isolated in 1947 in Uganda and belongs to the African lineage ZIKV. The 800/16 strain belongs to the Asian lineage and is very similar to the strains that caused an epidemic in South and Central America and in the Caribbean in 2015 and 2016.

• Keywords: viruses, Flaviviruses, Zika virus, clinical samples, molecular methods, nucleotide sequences, sequencing, phylogenetic analysis, genetic diversity