title: Interleukin-12 p40 mRNA expression in bovine leukemia virus-infected animals: increase in alymphocytosis but decrease in persistent lymphocytosis.
abstract: Interleukin-12 (IL-12), a key cytokine in immune regulation, has an important role in activating the cell-mediated immune response in infectious diseases. Recently, a dichotomy between IL-12 and IL-10 regarding progression of a variety diseases has emerged. IL-12 activates type 1 cytokine production and has an antagonistic effect on type 2 cytokines. Here, by using quantitative competitive PCR, we show that peripheral blood mononuclear cells from bovine leukemia virus-infected animals in the alymphocytotic stage of disease express an increased amount of IL-12 p40 mRNA. In contrast, IL-12 p40 mRNA expression by cells from animals with late-stage disease, termed persistent lymphocytosis, was significantly decreased compared to that by normal and alymphocytotic animals. Interestingly, IL-12 p40 mRNA was also detected in tumor-bearing animals. IL-12 p40 expression occurred only in monocytes/macrophages, not B or T lymphocytes. The present study combined with previous findings suggest that IL-12 in bovine leukemia virus-infected animals may regulate production of other cytokines such as gamma interferon and IL-10 and the progression of bovine leukosis in animals that develop more advanced disease such as a persistent lymphocytosis of B cells or B-cell lymphosarcoma.
authors.affiliation: Department of Animal Health and Biomedical Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: D
authors.initials: D
authors.lastname: Pyeon
authors.forename: G A
authors.initials: GA
authors.lastname: Splitter
mesh_terms: D000818:Animals; D002417:Cattle; D016583:Enzootic Bovine Leukosis / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D015870:Gene Expression; D018664:Interleukin-12 / Q000096:biosynthesis* / Q000235:genetics; D001909:Leukemia Virus, Bovine / Q000502:physiology*; D008218:Lymphocytosis / Q000378:metabolism* / Q000503:physiopathology; D008264:Macrophages / Q000378:metabolism; D009000:Monocytes / Q000378:metabolism; D012333:RNA, Messenger; D017735:Virus Latency
chemical_list: D012333:RNA, Messenger; D018664:Interleukin-12