AIDS Res Hum Retroviruses. 1997 May 20;13(8):713-8. Unique Identifier :
Regression of feline immunodeficiency virus (FIV) infection was observed
in seven of nine vertically infected kittens born to two chronically
infected mother cats. Both provirus and nonmaternal FIV antibody were
detected in all kittens by 4 weeks of age but only three of the seven
kittens were positive by blood mononuclear cell coculture. Between 10
and 14 months of age blood mononuclear cells from each of the seven cats
were negative at least once by polymerase chain reaction (PCR), but
evidence of virus infection was detected by coculture and/or PCR in
biopsied lymph node or bone marrow from five of the seven cats. Despite
this evidence of persistent tissue provirus, antibody production did not
persist in any of the cats beyond 1 year of age. All seven cats remained
asymptomatic although CD4 and CD8 T cell counts were in the low normal
range throughout the study. By contrast, two additional perinatally
infected littermates that were persistently virus isolation positive
developed rapid CD4 depletion and progressed to terminal
immunodeficiency by 9 weeks of age. Thus FIV infection can be
downregulated and/or sequestered to extremely low levels barely
detectable with the assays available, although absolute clearance of
virus may not occur. These observations are relevant to human
immunodeficiency virus (HIV) infection in paralleling both the apparent
regression" of HIV infection reported in some perinatally infected
infants and the low-level, apparently stable, infection established by
attenuated simian immunodeficiency viruses.
*Immunodeficiency Virus, Feline/GROWTH & DEVELOPMENT