Yukiko Nakata
National Institute of Radiological Sciences
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Yukiko Nakata.
Radiation Research | 1994
Akiko Uzawa; Gen Suzuki; Yukiko Nakata; Makoto Akashi; Harumi Ohyama; Atsuo Akanuma
Radiosensitivities of various human T-cell subsets were investigated by a proliferation assay and by a single-cell gel electrophoresis assay. Each T-cell subset was purified using a cell sorter and was induced to proliferate by ionomycin and interleukin 2. Unsorted T cells showed biphasic dose-survival curves, indicating the heterogeneity of T cells in terms of radiosensitivity. Purified CD4+ helper and CD8+ killer T cells showed similar biphasic dose-survival curves. Hence both T-cell subsets were composed of cells of different radiosensitivity. The T-cell subsets belonging to different activation stages such as CD45RO+ memory and CD45RO- naive T cells had different dose-survival curves. The former was more radiosensitive than the latter. The high radiosensitivity of CD45RO+ cells was also demonstrated by single-cell gel electrophoresis after irradiation. This is the first demonstration that a particular cell surface marker on T cells is correlated with greater radiosensitivity.
Journal of Immunological Methods | 1996
Masayuki Nomura; Yukiko Nakata; Toru Inoue; Akiko Uzawa; Shigeyuki Itamura; Kuniaki Nerome; Makoto Akashi; Gen Suzuki
Cytotoxic T lymphocytes (CTLs) recognise antigenic peptides in the context of major histocompatibility complex (MHC) class I molecules on virus-infected cells. The formation and transportation of antigenic peptides to class I MHC in the cells are multi-step reactions known as antigen processing. In order to design a good DNA vaccine, it is important to dissect the specificity of antigen processing. Here we describe the construction of an epitope-based plasmid vector as a device to investigate antigen processing in transfected cells. The epitope-based plasmid vector was constructed by insertion of an epitope-encoding minigene into the lacZ gene. We used a CTL epitope on influenza A virus nucleoprotein (NP366-374 epitope) as a model. Upon transfection, the epitope-based plasmid vector induced the expression of NP epitope antigenically as well as immunogenically. Immunization of mice with plasmid-transfected cells was able to induce NP epitope-specific CTLs in vivo. Moreover, the plasmid vector functioned as a gene vaccine; NP epitope-specific CTLs were primed in vivo upon transfection of the vector into dermis by electroporation. The results suggest that this epitope-based DNA delivery system may provide a new strategy for in vivo induction of epitope-specific CTLs to investigate antigen processing and presentation.
International Journal of Radiation Biology | 2001
Yoshiya Shimada; Mayumi Nishimura; Shizuko Kakinuma; T. Takeuchi; Toshiaki Ogiu; G. Suzuki; Yukiko Nakata; S. Sasanuma; Kazuei Mita; Toshihiko Sado
Purpose : To elucidate the characteristics of radiation carcinogenesis, the spectra of K- and N- ras oncogene mutations, loss of heterozygosity (LOH) and their association in X-ray-induced thymic lymphomas (TL) were determined by comparing with those of N -ethyl- N -nitrosourea (ENU)-induced and spontaneously occurring TL. Materials and methods : TL that arose in untreated, X-ray-irradiated and ENU-treated B6C3F1 mice were examined both for K- and N- ras mutations by PCR-SSCP and DNA sequencing and for LOH by PCR with polymorphic microsatellite markers. Results : (1) ras gene mutations were found in a proportion of TL from X-ray-exposed (~20%) and ENU-treated (30-40%) mice while no ras gene mutations were found in spontaneous TL. N- ras mutations were rare. (2) The spectrum of ras gene mutations was diverse and seemed to differ little between X-ray-induced and ENU-induced TL, even though there was a higher frequency of ras mutations in ENU-induced TL that clustered to K- ras codon 12. (3) The X-ray-induced TL showing K- ras mutation were associated with LOH on chromosome 6, while those showing no K- ras mutation were associated with high frequency of LOH on chromosomes 4, 11 and 12. Conclusion : These results demonstrate that, in the B6C3F1 mouse TL, X-ray-induced lymphomagenesis showed both the co-expression, yet low occurrence of allelic imbalance on chromosome 6 and K- ras mutation, and exclusive expression of frequent allelic imbalance on chromosomes 4, 11 and 12 and K- ras mutation.
Journal of Immunology | 1999
Gen Suzuki; Hirofumi Sawa; Yoshiyasu Kobayashi; Yukiko Nakata; Ken-ichi Nakagawa; Akiko Uzawa; Hisako Sakiyama; Shizuko Kakinuma; Kazuya Iwabuchi; Kazuo Nagashima
International Immunology | 1998
Gen Suzuki; Yukiko Nakata; Yoshiyuki Dan; Akiko Uzawa; Ken-ichi Nakagawa; Toshiyuki Saito; Kazuei Mita; Takuji Shirasawa
Journal of Immunology | 1995
Yukiko Nakata; K Matsuda; Akiko Uzawa; M Nomura; M Akashi; Gen Suzuki
Journal of Radiation Research | 2006
Yuka Ishida; Yasushi Ohmachi; Yukiko Nakata; Takeshi Hiraoka; Tsuyoshi Hamano; Shinji Fushiki; Toshiaki Ogiu
Cellular Immunology | 1998
Masako Nose; Akiko Uzawa; Masayuki Nomura; Yoshinori Ikarashi; Yukiko Nakata; Makoto Akashi; Gen Suzuki
International Immunology | 1999
Hiroki Kawasaki; Yukiko Nakata; Gen Suzuki; Kazuo Chihara; Takeshi Tokuhisa; Shunichi Shiozawa
International Immunology | 2000
Yukiko Nakata; Akiko Uzawa; Gen Suzuki