Mucosal transmission of cell-associated and cell-free feline immunodeficiency virus.
Mucosal infection by feline immunodeficiency virus (FIV) was assessed via a single exposure of the vaginal or rectal mucosa to either infectious peripheral blood mononuclear cells (PBMCs), infectious plasma, or cell-free cultured virus. All cats inoculated with cell-free cultured virus (100 or 400 TCID) and 9 of 10 cats inoculated with infected PBMCs (2 x 10(7) or 2 x 10(5)) became persistently viremic within 3 weeks. Neither cat inoculated with 2 x 10(3) PBMCs became viremic. Rectal and vaginal exposure were equally effective routes to induce viremia. CD4+ T cells and mitogen-stimulated PBMC proliferation declined in all infected cats. However, a transient PBMC proliferative response to FIV p24gag occurred in most virus-exposed cats, especially those that did not develop detectable infection. FIV was not transmitted by mucosal exposure to infectious virus in plasma (100 TCID), a dose > 10-fold that needed for infection by parental injection. In vitro studies suggested that a plasma heat-stable virus-neutralizing factor may be associated with failure of plasma virus to establish infection via the mucosal route. Mucosal FIV infection provides a new model with which to study early stages of infection and intervention in transmucosal lentivirus infections.
Burkhard
M J
MJ
Department of Pathology, College of Veterinary Medicine, Colorado State University, Fort Collins 80523, USA.
Obert
L A
LA
O'Neil
L L
LL
Diehl
L J
LJ
Hoover
E A
EA
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002415:Cats; D002474:Cell-Free System; D005260:Female; D006361:Heating; D016089:Immunodeficiency Virus, Feline / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D017403:In Situ Hybridization; D016180:Lentivirus Infections / Q000097:blood / Q000276:immunology / Q000635:transmission* / Q000821:virology; D008232:Lymphoproliferative Disorders; D008297:Male; D008934:Mitogens; D016133:Polymerase Chain Reaction; D012007:Rectum / Q000821:virology*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014621:Vagina / Q000821:virology*
D000914:Antibodies, Viral; D008934:Mitogens