Research Project
Grant-in-Aid for Scientific Research (C)
We have already reported that one subset of NKT cells, known as CD3^<int>IL-2Rβ+NK1.1-subset, expanded in the liver of P.yoelli 17XNL-infected C57BL/6(B6) mice and contributed to protection against malaria. On the other hand, accumulating results of our studies suggested that liver dendritic cells (DCs) might play a critical role in the regulation of immune responses through activation of liver NKT cells after malarial infection. However, this approach has not been clearly elucidated. In this study we attempted to analyze the phenotype and function of liver DCs in malaria infected mice.DCs are classified into two majour subpopulations ; myeloid DC (mDC) and plasmacytoid DC (pDC). Murine liver had high absolute number of PDCA-1+CD11c^<low>I-A-B220+DC (pDC) which produced IFN-α by stimulation with CpG in vitro. PDCA-1-CD11c^<high>I-A+B220-DC (mDC) were dominant in the spleen. DCs of both phenotypes were able to produce IL-12, IL-10 and TNFα. CD11c^<low>I-A-DC isolated from malaria infect … More ed mice increased in the liver and spleen at acute phase (7 days). These cells showed high expression of CD86 but decreased PDCA-1 expression and IFN-α production. I-A-CD11c^<low>DCs isolated from infected mice showed impaired production of cytokines as compared with mDCs. PDCA-1^+ cells in CD11c^<low>I-A- fraction of liver and spleen reappeared at recovery phase (after 25 days) of malarial infection. These results indicate that while mDCs activate NKT cells via cytokines and that activated NKT cells promote the protective activity and disease syndromes in malaria infected mice. pDCs induce the immunosuppressive effects due to impaired production of IFN-α. AIM (apoptosis inhibitor expressed by MΦ) deficient mice lack some of MΦ and DC functions and were found to recover more quickly from malarial infection than B6 mice. γδT cells expanded in the liver and spleen, especially in the recovery phase. These findings clearly showed the phenotypical and functional change of DCs in the liver and may support the view that liver DC regulate the function of NKT cells in the liver after malarial infection. Less
All 2006 2005 2004
All Journal Article (24 results)
Immunology 117
Pages: 127-135
Immunology and Cell Biology 83
Pages: 638-642
Immunologic Research 33
Pages: 23-34
Immuno Cell Biol 83
Immunol Res 33
Southeast Asian J.Trop.Med.Public Health 36
Pages: 1092-1095
Immunologic research 33
Southeast Asian Journal of Tropical Medicine and Public Health 36
Tropical Medicine and Health 33
Pages: 103-104
Journal of Immunology 173
Pages: 579-585
Journal of Clinical and Experimental Hematopathology 44
Pages: 1-9
Immunology 113
Pages: 371-377
J.Immunol 173
J.Clin.Exp.Hematopathol 44
Journal of Clinical and Experimental Hematology 44
Hepatogastroenterology 51
Pages: 329-333
Biomedical Research 25
Pages: 93-100
Pages: 201-207