T Cells Overexpressing Interferon-γ and Interleukin-10 Are Found in Both the Thymus and Secondary Lymphoid Tissues of Feline Immunodeficiency Virus-Infected Cats

• Published in: The Journal of infectious diseases 2000-02, Vol.181 (2), p.564-575
• Main Authors: Liang, Yinghua, Hudson, Lola C., Levy, Julie K., Ritchey, Jerry W., Tompkins, Wayne A. F., Tompkins, Mary B.
• Format: Article
• Language: English
• Subjects: AIDS/HIV; Animals; B lymphocytes; B-Lymphocytes - immunology; Biological and medical sciences; Cats; CD4 antigen; CD8 antigen; Cytokines; Experimental viral diseases and models; Feline Acquired Immunodeficiency Syndrome - immunology; Feline Acquired Immunodeficiency Syndrome - pathology; feline immunodeficiency virus; g-Interferon; Gene Products, gag - metabolism; Immunodeficiency Virus, Feline - immunology; Immunohistochemistry; In Situ Hybridization; Infections; Infectious diseases; Interferon-gamma - biosynthesis; Interferon-gamma - genetics; Interleukin-10 - biosynthesis; Interleukin-10 - genetics; Lymph nodes; Lymph Nodes - immunology; Lymph Nodes - pathology; Major Articles; Medical sciences; Messenger RNA; Physiological immunosuppression; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - genetics; RNA, Messenger - metabolism; T lymphocytes; T-Lymphocyte Subsets - immunology; Thymocytes; Thymus Gland - immunology; Thymus Gland - pathology; Viral diseases; Viruses
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/315226

Similar to human immunodeficiency virus type 1, feline immunodeficiency virus (FIV) replicates in the thymus of infected animals, causing marked alteration in thymic lymphocyte subpopulations. The immune phenotype and cytokine patterns in the thymus and secondary lymphoid tissues of FIV-infected cats were investigated. FIV infection caused an acute-stage transient reduction in CD4CD8 double-positive thymocytes, a marked increase in CD8 single-positive thymocytes, and formation of thymic B cell lymphoid follicles. Interferon (IFN)-γ and interleukin (IL)-10 mRNA were up-regulated in both the thymus and lymph nodes of FIV-infected cats. Analysis of purified CD4 and CD8 cells revealed that CD4 cells produced most of the IL-10, whereas IFN-γ was produced by both subsets. Quantitative-competitive reverse-transcription polymerase chain reaction analysis revealed that thymocytes, especially CD4CD8 thymocytes, had much greater levels of gag mRNA than did lymph node T cells. Thus, overexpression of IFN-γ and IL-10 is a feature of the thymus and secondary lymphoid tissues of FIV-infected cats.