%0 Journal Article
%T Identification of novel subgroup A variants with enhanced receptor binding and replicative capacity in primary isolates of anaemogenic strains of feline leukaemia virus
%A Hazel Stewart
%A Karen W Adema
%A Elizabeth L McMonagle
%A Margaret J Hosie
%A Brian J Willett
%J Retrovirology
%D 2012
%I BioMed Central
%R 10.1186/1742-4690-9-48
%X Within each isolate of FeLV-C, we identified variants that were ostensibly subgroup A by nucleic acid sequence comparisons, but which bore mutations in the RBD. One such mutation, N91D, was present in multiple isolates and when engineered into a molecular clone of the prototypic FeLV-A (Glasgow-1), enhanced replication was noted in feline cells. Expression of the N91D Env on murine leukaemia virus (MLV) pseudotypes enhanced viral entry mediated by the FeLV-A receptor THTR1 while soluble FeLV-A Env bearing the N91D mutation bound more efficiently to mouse or guinea pig cells bearing the FeLV-A and -C receptors. Long-term in vitro culture of variants bearing the N91D substitution in the presence of anti-FeLV gp70 antibodies did not result in the emergence of FeLV-C variants, suggesting that additional selective pressures in the infected cat may drive the subsequent evolution from subgroup A to subgroup C.Our data support a model in which variants of FeLV-A, bearing subtle differences in the RBD of Env, may be predisposed towards enhanced replication in vivo and subsequent conversion to FeLV-C. The selection pressures in vivo that drive the emergence of FeLV-C in a proportion of infected cats remain to be established.
%K Feline leukaemia virus
%K FeLV
%K Anaemia
%K Receptor
%U http://www.retrovirology.com/content/9/1/48/abstract