Failure of FIV-infected cats to control Toxoplasma gondii correlates with reduced IL2, IL6, and IL12 and elevated IL10 expression by lymph node T cells.
Increased susceptibility to intracellular pathogens in HIV-infected individuals and FIV-infected cats is attributed to a defective T-helper 1 (Th1) immune response. However, little is known about specific cytokine responses to secondary pathogens. To address this question, control and FIV-infected cats were challenged with Toxoplasma gondii, and lymph node cells analyzed for cytokine mRNA expression. Twenty-four weeks post-FIV infection, prior to T. gondii challenge, IL2 and IL12 mRNAs were depressed, whereas IL10 and IFNgamma mRNAs were increased in CD4+ and CD8+ subsets. Following T. gondii challenge, control cats showed increased expression of IL2, IFNgamma, IL10, IL12, and IL6 mRNAs. In contrast, IL2, IL6, IFNgamma, and IL12 mRNAs were suppressed in FIV-T. gondii co-infected cats, whereas IL10 remained at the high prechallenge levels. IFNgamma and IL10 mRNAs were produced by both CD4+ and CD8+ cells in FIV-T. gondii cats. Elevated IL10 may suppress a Th1 cytokine response to T. gondii challenge.
Levy
Julie K
JK
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, P.O. Box 100126, 2015 SW 16th Avenue, Gainesville, FL 32610, USA. levyj@mail.vetmed.ufl.edu
Liang
Yinghua
Y
Ritchey
Jerry W
JW
Davidson
Michael G
MG
Tompkins
Wayne A
WA
Tompkins
Mary B
MB
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002371:Cat Diseases / Q000235:genetics / Q000276:immunology*; D002415:Cats; D015870:Gene Expression; D016089:Immunodeficiency Virus, Feline; D016753:Interleukin-10 / Q000235:genetics; D018664:Interleukin-12 / Q000235:genetics; D007376:Interleukin-2 / Q000235:genetics; D015850:Interleukin-6 / Q000235:genetics; D007378:Interleukins / Q000235:genetics*; D016180:Lentivirus Infections / Q000150:complications / Q000235:genetics / Q000276:immunology / Q000662:veterinary*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology; D014124:Toxoplasmosis, Animal / Q000150:complications / Q000235:genetics / Q000276:immunology*
D007376:Interleukin-2; D015850:Interleukin-6; D007378:Interleukins; D012333:RNA, Messenger; D016753:Interleukin-10; D018664:Interleukin-12