Cellular segregation of feline leukemia provirus and viral RNA in leukocyte subsets of long-term experimentally infected cats.
Cats exposed to feline leukemia virus (FeLV) may develop different outcomes of the infection. However, during acute infection blood proviral and viral RNA loads of cats with progressive and regressive infection are not significantly different. Thus, not the overall loads but rather those of specific leukocyte subsets may influence the infection outcome. By combining fluorescence activated cell sorting (FACS) with sensitive real-time TaqMan PCR and reverse transcriptase (RT) PCR, we established in the present study the methods to determine FeLV proviral and viral RNA loads in specific leukocyte subsets. In addition, they were applied to analyze long-term persistently FeLV-infected (p27-positive) and FeLV exposed but nonantigenemic (p27-negative), nonviremic cats. In the latter animals, CD4(+) and B lymphocytes exhibited the highest proviral loads, whereas in p27-positive cats, all leukocyte subsets showed similar high loads. In p27-positive cats, monocytes and granulocytes bore the highest viral RNA loads, whereas only one p27-negative cat was positive for viral RNA in T lymphocytes. To our knowledge, this is the first study to investigate FeLV proviral and viral RNA loads in leukocyte subsets of FeLV exposed cats. The herein described methods are important prerequisites to gain a deeper insight into the pathogenesis of FeLV infection.
Pepin
Andrea C
AC
Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Switzerland.
Tandon
Ravi
R
Cattori
Valentino
V
Niederer
Eva
E
Riond
Barbara
B
Willi
Barbara
B
Lutz
Hans
H
Hofmann-Lehmann
Regina
R
D000818:Animals; D002371:Cat Diseases / Q000821:virology; D002415:Cats; D005256:Leukemia Virus, Feline / Q000235:genetics* / Q000302:isolation & purification; D007942:Leukemia, Experimental; D016582:Leukemia, Feline / Q000821:virology; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary*; D011533:Proviruses / Q000302:isolation & purification* / Q000502:physiology; D012367:RNA, Viral / Q000302:isolation & purification*; D012192:Retroviridae Infections / Q000662:veterinary*; D014412:Tumor Virus Infections / Q000662:veterinary*; D019562:Viral Load; D014766:Viremia
D012367:RNA, Viral