Importance of CD8(+)Vbeta8(+) T cells in IFN-gamma-mediated prevention of toxoplasmic encephalitis in genetically resistant BALB/c mice.

Abstract

In our attempt to identify a major T cell population(s) that recognizes protective Toxoplasma gondii antigens and produces interferon-gamma (IFN-gamma) for prevention of toxoplasmic encephalitis (TE), we found T cell receptor Vbeta8(+) cells to be the most frequent IFN-gamma-producing population infiltrated into the brain of T. gondii-infected BALB/c mice genetically resistant to the disease. To examine the role of IFN-gamma production by this T cell population for resistance, we transferred Vbeta8(+) immune T cells purified from spleens of infected BALB/c and IFN-gamma(/) mice into infected, sulfadiazine-treated, athymic nude mice. After discontinuation of sulfadiazine treatment, control nude mice that had not received any T cells and animals that had received Vbeta8(+) T cells from IFN-gamma(/) mice all died because of reactivation of infection (TE). In contrast, animals that had received the cells from BALB/c mice survived. Thus, IFN-gamma production by Vbeta8(+) T cells plays an important role in prevention of TE in these animals. When Vbeta8(+) immune T cells were divided into CD4(+) and CD8(+) subsets, a potent protective activity was observed only in the CD8(+) subset, whereas a combination of both subsets provided greater protection than did the CD8(+)Vbeta8(+) population alone. These results indicate that the CD8(+) subset of Vbeta8(+) T cells is a major afferent limb of IFN-gamma-mediated resistance of BALB/c mice against TE, although the CD4(+) subset of the T cell population works additively or synergistically with the CD8(+)Vbeta8(+) population.

• Authors: Xisheng Wang, Jennifer Claflin, Hoil Kang, Yasuhiro Suzuki
• Journal: Journal of interferon & cytokine research : the official journal of the International Society for Interferon and Cytokine Research (J Interferon Cytokine Res) Vol. 25 Issue 6 Pg. 338-44 (Jun 2005) ISSN: 1079-9907 [Print] United States
• PMID: 15957957 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Antigens, Protozoan
• Receptors, Antigen, T-Cell, alpha-beta
• Interferon-gamma

Topics

• Animals
• Antigens, Protozoan (immunology)
• CD8-Positive T-Lymphocytes (immunology)
• Encephalitis (immunology, parasitology)
• Female
• Interferon-gamma (deficiency, immunology)
• Mice
• Mice, Inbred BALB C
• Mice, Knockout
• Receptors, Antigen, T-Cell, alpha-beta (immunology)
• T-Lymphocyte Subsets (immunology)
• Toxoplasma (immunology)
• Toxoplasmosis, Animal (immunology)
• Toxoplasmosis, Cerebral (immunology)