In vitro and in vivo assessment of orf virus (ORFV) by electron microscopy

Autor: Nawab Nashiruddullah, Debesh C. Pathak, Nagendra N. Barman, Jafrin A. Ahmed, Probodh Borah, Safeeda S. Begum, Saidul Islam
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Veterinarski arhiv
Volume 88
Issue 6
ISSN: 1331-8055
0372-5480
Popis: Transmission electron microscopy (TEM) was employed for describing skin and scab lesions in goats affected by orf virus and to demonstrate the parapoxvirus from clinical suspensions by negative staining and ORFV confirmation by immunogold electron microscopy. All samples were confirmed as parapoxvirus by semi-nested PCR amplification of partial gene encoding for the B2L envelope protein. Skin lesions were characterized by ballooning degeneration and loss of desmosomes of the spinosum cells, cytolysis and vesicle formation. Nuclear changes included chromatin margination and increase in electron density. Cytoplasmic changes were typical of cell swelling, vacuolation and the presence of uniform, moderately electron dense viroplasm, situated in the perinuclear region. Various intracellular forms including immature virions (IV), mature virions (IMV) and wrapped virions (WV) were observed in the cytoplasm. All these forms of ORFV were observed morphologically akin to vaccinia virus (VACV). Negative staining of clinical samples and viral suspensions showed typical parapoxvirus morphology with a characteristic criss-cross tubular surface pattern. Both ‘capsule’ form (‘C’ form) and ‘mulberry’ form (‘M’ form) of the virus were demonstrated. ORFV speciation was confirmed by immunogold tagging using a monoclonal antibody in ultra-thin skin section.
U radu je za opisivanje lezija na koži i krastama kod koza inficiranih orfvirusom primijenjena transmisijska elektronska mikroskopija (TEM). Dokaz parapoksvirusa iz suspenzije i potvrda ORFV-a obavljeni su tehnikom negativnog bojenja te imunogold elektronskom mikroskopijom. Svi su uzorci potvrđeni kao parapoksvirusi pomoću poluugniježđene lančane reakcije polimerazom kojom je umnožen dio gena B2L odgovornog za protein ovojnice. Lezije na koži karakterizirane su balonskom degeneracijom i gubitkom dezmosoma spinoznih stanica, citolizom te stvaranjem vezikula. Promjene u jezgri uključivale su rub kromatina i povećanje elektronske gustoće. Citoplazmatske promjene bile su tipične za bubrenje stanica, vakuolaciju i prisutnost uniformnog, umjereno elektronički gustog viroplazma smještenog u međumembranskom području. U citoplazmi su zabilježeni različiti unutarstanični oblici, uključujući nezrele virione (IV), zrele virione (IMV) i omotane virione (WV). Svi su oblici ORFV-a pokazali morfološku srodnost s virusom vakcinije (VACV). Negativno bojenje uzoraka i suspenzija pokazali su tipičnu građu parapoksvirusa s karakterističnim križno-cjevastim uzorkom na površini. Također, prikazana su oba oblika virusa, kapsula (oblik C) i dud (oblik M). Specijacija ORFV-a potvrđena je imunogold obilježavanjem pri čemu su korištena monoklonska protutijela u ultratankom rezu kože.
Databáze: OpenAIRE