Hiroshi Kosaka

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In this report, we show that cross-presentation of self-antigens can lead to the peripheral deletion of autoreactive CD8(+) T cells. We had previously shown that transfer of ovalbumin (OVA)-specific CD8(+) T cells (OT-I cells) into rat insulin promoter-membrane-bound form of OVA transgenic mice, which express the model autoantigen OVA in the proximal(More)
Ovalbumin (OVA)-specific CD8+ T cells from the T cell receptor-transgenic line OT-I (OT-I cells) were injected into unirradiated transgenic RIP-mOVA mice, which express a membrane-bound form of OVA (mOVA) in the pancreatic islet beta cells and the renal proximal tubular cells. OT-I cells accumulated in the draining lymph nodes (LN) of the kidneys and(More)
Recently, we demonstrated that major histocompatibility complex class I-restricted cross-presentation of exogenous self-antigens can induce peripheral T cell tolerance by deletion of autoreactive CD8+ T cells. In these studies, naive ovalbumin (OVA)-specific CD8+ T cells from the transgenic line OT-I were injected into transgenic mice expressing(More)
To test whether unprimed CD8+ cells can recognize class I alloantigens presented selectively on non-bone marrow (BM)-derived cells, unprimed parental strain CD8+ cells were transferred to long-term parent-->F1 BM chimeras prepared with supralethal irradiation. Host class I expression in the chimeras was undetectable on BM-derived cells and, in spleen, was(More)
Information was sought on the features of epithelial cells in the murine thymic medulla. The expression of major histocompatibility complex (MHC) molecules on medullary epithelium was defined by light microscopy with the aid of bone marrow chimeras and MHC-transgenic mice. A proportion of medullary epithelial cells was found to show conspicuously high(More)
To clarify the chronic effect of lead exposure on the central and peripheral nervous systems (CNS and PNS), we performed neurophysiological tests on 41 lead-exposed male workers. Unexposed workers (controls, N = 39) were examined for auditory brain stem response (ABR), and their ABR parameters were compared with those of 15 lead-exposed workers age-matched(More)
Long-term H-2-heterozygous a----(a x b)F1 bone marrow (BM) chimeras prepared with supralethal irradiation (1,300 rad) are devoid of Ia+ host BM-derived antigen-presenting cells (APC), but show quite strong host Ia expression in germinal centers, probably on follicular dendritic cells (a class of nonhemopoietic stromal cells). To examine whether Ia(More)
OBJECTIVES In order to clarify the effect of lead on higher cerebral functions, lead-exposed workers (Pb group) and controls were examined for event-related potentials. SUBJECTS AND METHODS Fourteen lead-exposed workers with a mean age of 57.1 yr (SD=4.27, range 48-64; lead concentration of whole blood ranged from 33 to 106 microg/dl with a mean of 58.6(More)
Accumulating evidence indicates that VEGF and matrix metalloproteinase-9 (MMP-9) play a central role in the development of peritumoral brain edema (PTBE) associated with human brain tumors. However, the roles of these proteins, particularly of MMP-9, in PTBE associated with benign meningiomas have not been elucidated. We investigated the association between(More)