Does endogenous feline leukemia virus occur as a risk factor?: A molecular characterization study from Türkiye Molecular analysis of enFeLVs


Published: Oct 18, 2023
Keywords:
domestic cats endogenous exogenous feline leukemia virus molecular characterization Türkiye
BT Koç
https://orcid.org/0000-0002-4279-6233
TÇ Oğuzoğlu
Abstract

Feline leukemia virus (FeLV) is a feline retrovirus that causes various effects on cat health. FeLV, along with other retroviruses, has altered in terms of molecular structure and pathogenetic and clinical status due to integration into the host genome. In this study, we aimed to determine the presence of enFeLV in the indoor-cats and provide a comparison with potential exFeLV prevalence. Additionally, we aimed to investigate the relationship between positive cases of enFeLV and risk factors including age, gender, breed. We collected 200 samples from domestic cats in Turkey for molecular diagnosis and characterization of en- or exFeLV. Amplified products were purified and sequenced using the Sanger method. According to the phylogenetic tree, our sequences constituted two main clusters that were divergent from each other in Group-2 enFeLVs. The unit of “Health status” in the overall population comprised 161 healthy and 39 diseased cats according to clinical diagnosis. In diseased cats, 17 were found to be enFeLV positive (17/39; 43.6%). “Gender”, “age”, and “breed” were not found to be risk factors for the presence of enFeLV among domestic cats in this study. With regards to the outcomes of the study, we submit that both variants of FeLV should be tested prior to initiating a vaccination program.

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References
Anai Y, Ochi H, Watanabe S, et al (2012) Infectious endogenous retro
viruses in cats and the emergence of recombinant viruses. J Virol
Berry BT, Ghosh AK, Kumar DV, et al (1988) Structure and function of
endogenous feline leukemia virus long terminal repeats and adjoining
regions. J Virol 62:3631-3641
Chiu ES, McDonald CA, VandeWoude S (2021) Endogenous feline leu
kemia virus (FeLV) siRNA transcription may interfere with exoge
nous FeLV infection. J Virol 95:e0007021. https://doi.org/10.1128/
JVI.00070-21
Dunham SP, Graham E (2008) Retroviral infections of small animals.
Vet Clin North Am Small Anim Pract 38:879-901, ix. https://doi.
org/10.1016/j.cvsm.2008.03.005
Erbeck K, Gagne RB, Kraberger S, et al (2021) Feline leukemia vi
rus (FeLV) endogenous and exogenous recombination events re
sult in multiple FeLV-B subtypes during natural infection. J Virol
Erol N, Pasa S (2013) An Investigation of the Feline Immunodeficien
cy Virus (FIV) and Feline Leukemia Virus (FeLV) Infections in Cats
in Western Turkey. Acta Sci Vet 41:1166. https://doi.org/10.1017/ S0950268812001707
Hartmann K (2012) Clinical aspects of feline retroviruses: a review. Vi
Hofmann-Lehmann R, Cattori V, Tandon R, et al (2007) Vaccination
against the feline leukaemia virus: outcome and response catego
ries and long-term follow-up. Vaccine 25:5531-5539. https://doi.
org/10.1016/j.vaccine.2006.12.022
Hoover EA, Mullins JI (1991) Feline leukemia virus infection and diseas
es. J Am Vet Med Assoc 199:1287-1297
Jarrett O, Hardy WD Jr, Golder MC, Hay D (1978) The frequency of oc
currence of feline leukaemia virus subgroups in cats. Int J Cancer
:334-337
Krunic M, Ertl R, Hagen B, et al (2015) Decreased expression of endog
enous feline leukemia virus in cat lymphomas: a case control study.
Kumar S, Stecher G, Li M, Knyaz C, Tamura K (2018) MEGA X: Molec
ular evolutionary genetics analysis across computing platforms. Mol
Biol Evol 35:1547-1549. https://doi.org/10.1093/molbev/msy096
Lauring AS, Anderson MM, Overbaugh J (2001) Specificity in recep
tor usage by T-cell-tropic feline leukemia viruses: implications for
the in vivo tropism of immunodeficiency-inducing variants. J Virol
Ledesma-Feliciano C, Hagen S, Troyer R, et al (2018) Replacement of
feline foamy virus bet by feline immunodeficiency virus vif yields
replicative virus with novel vaccine candidate potential. Retrovirolo
Liu D (ed) (2016) Molecular detection of animal viral pathogens. CRC
Press, London, England
Menéndez-Arias L (2010) Special issue: retroviral enzymes. Viruses
Miyazawa T, Yoshikawa R, Golder M, et al (2010) Isolation of an infec
tious endogenous retrovirus in a proportion of live attenuated vaccines
for pets. J Virol 84:3690-3694. https://doi.org/10.1128/JVI.02715-09
Muz D, Can H, Karakavuk M, Doskaya M, Ozdemir H.G, Doskaya A.
D,Sahar E.A,Pektas B, Karakus M, Toz S, Osbel Y, Guruz A.Y, Muz
M.N. (2021). The molecular and serological investigation of Feline
immunodeficiency virus and Feline leukemia virus in stray cats of
Western Turkey. Comp Immunol Microbiol Infect Dis 78:101688.
Neil JC, Fulton R, Rigby M, Stewart M (1991) Feline leukaemia virus:
generation of pathogenic and oncogenic variants. Curr Top Microbiol
Oğuzoğlu TÇ, Muz D, Timurkan MÖ, et al (2013) Prevalences of feline
coronavirus (FCoV), feline leukaemia virus (FeLV), feline immuno
deficiency virus (FIV) and feline parvovirus (FPV) among domestic
cats in Ankara, Turkey. Rev Med Vet (Toulouse) 164:511-516. https://
doi.org/10.1501/vetfak_0000002438
Polani S, Roca AL, Rosensteel BB, et al (2010) Evolutionary dynam
ics of endogenous feline leukemia virus proliferation among spe
cies of the domestic cat lineage. Virology 405:397-407. https://doi.
org/10.1016/j.virol.2010.06.010
Powers JA, Chiu ES, Kraberger SJ, et al (2018) Feline leukemia virus
(FeLV) disease outcomes in a domestic cat breeding colony: Rela
tionship to endogenous FeLV and other chronic viral infections. J Vi
Roca AL, Nash WG, Menninger JC, et al (2005) Insertional polymor
phisms of endogenous feline leukemia viruses. J Virol 79:3979-3986.
Stewart H, Jarrett O, Hosie MJ, Willett BJ (2011) Are endogenous feline
leukemia viruses really endogenous? Vet Immunol Immunopathol
Tandon R, Cattori V, Willi B, et al (2008) Quantification of endoge
nous and exogenous feline leukemia virus sequences by real-time
PCR assays. Vet Immunol Immunopathol 123:129-133. https://doi.
org/10.1016/j.vetimm.2008.01.027
Yilmaz H, Tekelioglu BK, Gurel A, et al (2017) Frequency, clinicopath
ological features and phylogenetic analysis of feline morbillivirus in
cats in Istanbul, Turkey. J Feline Med Surg 19:1206-1214. https://doi.
org/10.1177/1098612X16686728
Yuksek N, Kaya A, Altug N, et al (2005) Prevalence of feline retrovirus
infections in Van cats. Bull Vet Inst Pulawy 49:375-377. https://doi.
org/10.1292/jvms.62.921