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Yoshiki Shigematsu

Publications and source records attributed to Yoshiki Shigematsu.

5 recordsLinked to original sources

Identification of HLA-A24 restricted shared antigen recognized by autologous cytotoxic T lymphocytes from a patient with large cell carcinoma of the lung.

The aim of the present study was to elucidate the tumor-specific cellular immunological responses occurring in a patient with large cell carcinoma of the lung who had no evidence of recurrence following surgical resections of both a primary lung lesion and a metastatic adrenal lesion. We analyzed an autologous tumor-specific cytotoxic T lymphocytes (CTL clone F2b), which were HLA-A*2402 restricted from regional lymph node lymphocytes. The F2b possessed T cell receptor (TCR) using the Valpha5 and Vbeta7 gene segment. The existence of precursor CTL (pCTL) against autologous tumor cells (A904L) was analyzed using CTL clone-specific PCR. Lymphocytes with the same TCR as F2b were detected in the primary tumor tissue, regional lymph node and the peripheral blood collected from the patient 3 years after the operation. Using the F2b, we identified a cDNA clone encoding the tumor antigen using cDNA expression cloning method. The gene was found to encode splicing variant of the Tara gene. Finally, we identified the 9-mer Ag peptide, using constructions of mini-genes. The F2b recognized 3 out of 7 HLA-A24 positive allogeneic tumor cell lines and in 1 out of 7 HLA-A24 negative allogeneic tumor cell lines when transfected with HLA-A24. This peptide is therefore considered to be potentially useful for performing specific immunotherapy in a significant proportion of lung cancer patients bearing HLA-A24.

Alternative Splicing↗

Tracheobronchopathia osteochondroplastica occurring in a subsegmental bronchus and causing obstructive pneumonia.

A 59-year-old man was referred to the University of Occupational and Environmental Health hospital because a chest roentgenogram obtained at an annual medical examination showed an abnormal shadow. We treated the patient for tracheobronchopathia osteochondroplastica, which caused segmental obstructive pneumonia that proved to be difficult to accurately diagnose before surgery.

Humans↗

The immunomodulatory effect of cryopreservation in rat tracheal allotransplantation.

BACKGROUND: Cryopreservation is one solution to the problem of donor organ deficit. To investigate the effect of cryopreservation on tracheal allografts, we performed 2 experiments in rats. METHODS: In Experiment 1, we assessed second-set graft rejection. Two weeks after primary heterotopic transplantation (Group 1, fresh isografts; Group 2, fresh allografts from Lewis rats; and Group 3, cryopreserved allografts from Lewis rats; n = 5, respectively), each animal underwent secondary heterotopic grafting with isografts and allografts from Lewis and Wistar Furth rats (n = 5, respectively). Four weeks after the secondary transplantation, all grafts were retrieved for histologic analysis. In Experiment 2, we assessed the long-term results of allograft cryopreservation, without immunosuppression therapy. Six months after transplantation of fresh (Group 4) and cryopreserved (Group 5) allografts, the tracheal segments (each group, n = 5) were histologically evaluated. RESULTS: In Experiment 1, only the secondary allografts from Lewis rats in Group 2 did not maintain lumen structure and often showed dislocated or destroyed cartilage. Second-set graft rejection was specifically recognized in Group 2, but not in Group 1 or 3. In Experiment 2, the cryopreserved allografts appeared almost normal and lumen rigidity was preserved 6 months after transplantation. These allografts were superior to the fresh allografts in patency and in cartilage dislocation and mononuclear cell infiltration scores, but not in the viable chondrocyte ratio. CONCLUSIONS: We conclude that cryopreservation may produce successful long-term results because of its immunomodulatory effect on tracheal allografts.

Animals↗

Effect of IgG produced by tumor-infiltrating B lymphocytes on lung tumor growth.

BACKGROUND: Tumor-infiltrating B lymphocytes (TIB) are often observed in lung cancer. The role of TIB in tumor growth has not been well investigated. MATERIALS AND METHODS: Forty-four surgically-resected human lung cancer tissues were xenotransplanted into SCID mice. Their blood was collected and the volume of the transplanted tumors was measured regularly. The correlations between the IgG titer in the sera and the growth of the transplanted tumors according to the clinicopathological variables were examined. RESULTS: Human IgG production from TIB was observed in the all xenotransplanted mice. Twenty-seven out of the 44 tumors regressed gradually. The average serum human IgG level of the tumor regressors (n = 10) was significantly higher than that of the progressors (n = 9) in squamous cell carcinoma (p = 0.02), while there was no significant difference in the other histological groups. CONCLUSION: IgG produced by TIB might play a crucial role in preventing tumor growth in squamous cell carcinoma.

Animals↗

Antigens recognized by IgG derived from tumor-infiltrating B lymphocytes in human lung cancer.

BACKGROUND: Lung cancer tissues are often infiltrated by B lymphocytes, but it is not clear whether these infiltrations represent tumor-specific immune response or a nonspecific reaction. MATERIALS AND METHODS: The serological analysis of recombinant cDNA expression libraries (SEREX) were previously modified using a severe combined immunodeficient (SCID) mice model engrafted with fresh human lung cancer. Here, a panel of antigens recognized by tumor-infiltrating B lymphocytes (TIB) in human lung cancer were characterized. RESULTS: The modified SEREX analysis identified 22 distinct antigens in a large cell carcinoma of the lung. Sequence analysis and real time-PCR analysis showed that 55% of isolated antigens were overexpressed in tumor tissues and 9% had mutation. CONCLUSION: The results of this study indicate that the humoral immune response of TIB in lung cancer patients can be detected in the xenotransplanted SCID mouse model and our modification shows high sensitivity and specificity for identification of tumor antigens.

Animals↗