Biomedical subjects

M Tamai

Publications and source records attributed to M Tamai.

351 records · Page 20Linked to original sources

PubMedDate not supplied

Cytologic finding of chyloascites in lymphangioleiomyomatosis. A case report.

BACKGROUND: Lymphangioleiomyomatosis is a rare disease, histologically characterized by an abnormal proliferation of smooth muscle around the lymphatics. Lung is the most common site of involvement, and patients usually present with dyspnea, chest pain, and cough. Chylous pleural effusion and ascites occasionally appear during the course of the disease. There are only a few reports on the cytologic findings in this disease. To our knowledge, the cytologic findings of chylous pleural effusion and chyloascites have not been reported before. CASE: A 23-year-old female presented with chylothorax, chyloascites and a retroperitoneal mass. Cytologic examination of chylous pleural effusion and chyloascites revealed numerous cohesive and thick clusters of cells with a high nuclear/cytoplasmic ratio, oval nuclei and slightly increased chromatin content. Mitosis and necrosis were not observed. Exploratory laparotomy and transbronchial lung biopsy were performed, and the histologic diagnosis was lymphangioleiomyomatosis involving the retroperitoneal lymph nodes, uterine fundus and lungs. Immunohistochemistry showed that the characteristic clusters in chylous fluids were positive for alpha-smooth muscle actin. CONCLUSION: A diagnosis of lymphangioleiomyomatosis is possible from cytologic findings of effusions with the aid of clinical findings.

Adult↗

PubMedDate not supplied

Transplantation of retinal pigment epithelium using viable cryopreserved cells.

Transplantation of retinal pigment epithelium (RPE) may have potential clinical application for the surgical treatment of RPE-specific retinal degeneration, including age-related macular degeneration. The feasibility of an RPE storage bank has been investigated by experimenting with transplantation using viable, cryopreserved RPE cells. Fresh and cultured fetal human and bovine RPE cells were cryopreserved in 90% fetal bovine serum containing 10% dimethyl sulfoxide. The viability of the cells before and after cryopreservation was evaluated by trypan blue dye exclusion test, microculture tetrazolium assay (MTA), tissue culture, and transplantation after cryopreservation. The origin of RPE cells before and after cryopreservation was assessed by immunocytochemistry, immunoblotting, and indirect ELISA of RPE-marker protein using cytokeratin for cultured fetal human RPE cells and by immunocytochemistry of cellular retinaldehyde-binding protein (CR-ALBP) for cultured bovine RPE cells. Freshly isolated and cryopreserved uncultured bovine RPE cells were transplanted by posterior transscleral approach into the subretinal spaces of adult albino rabbits and 23-day-old Royal College of Surgeons (RCS) rats with a 33 gauge Hamilton syringe. Following surgery, artificial retinal blebs were confirmed by fundus examination. Morphologic examination was performed postoperatively by light and electron microscopy in albino rabbits and by light microscopy in RCS rats up to 3 mo. Control subretinal injections using vehicle solution also were performed in RCS rats. Cultured fetal human and bovine RPE cells after cryopreservation were found to be viable, based on the results of trypan blue dye exclusion test, MTA, tissue culture, and transplantation. Expression and reexpression of cytokeratin intermediate filaments in cultured fetal human RPE were demonstrated by immunocytochemistry, immunoblotting, and indirect ELISA before and after cryopreservation. Immunocytochemistry of CRALBP before and after cryopreservation in uncultured bovine RPE cells disclosed expression and reexpression of RPE cell marker protein. No uncultured fetal human RPE cells showed proliferation in tissue culture after cryopreservation. In rabbits, light and electron microscopy disclosed xenografted RPE cells residing on Bruch's membrane of the host retina. No sign of graft vs. host reaction was observed. No morphologic difference was noted between the fresh and 10-day-old cryopreserved RPE cells in situ following transplantation at day 25. In RCS rats, subretinal injection of 3-wk-old cryopreserved bovine RPE cells partially rescued photoreceptor cells locally at the transplanted area observed at 3 mo postoperatively. The retinal photoreceptors at the inferior hemisphere of the transplanted eye and the eye injected with vehicle solution showed no rescue effect. We found that cryopreserved cultured fetal human RPE cells and uncultured and cultured bovine RPE cells can be used for RPE transplantation studies. The ability to create an RPE storage bank as a source of donor cells may result in several clinical advantages.

Animals↗

PubMedDate not supplied

Characterization of iris pigment epithelial cell for auto cell transplantation.

To establish auto iris pigment epithelial (IPE) transplantation, we characterized the properties of IPE cells and the method of culture using auto serum. Monkey and human IPE cells were obtained and cultured in several conditions, using auto, mouse, rabbit, bovine, or human serum. Immunocytochemical study was performed to confirm that the cells were epithelial in origin. The proliferation rate of the IPE was also calculated from fresh human IPE cells, which were obtained during filtering glaucoma surgery. Proliferation rate was also compared to that of retinal pigment epithelial (RPE) cells. Reverse-transcriptase and polymerase chain reaction for melanogenesis was performed, and the amount of pigment in the IPE cells was also calculated. Mouse and rabbit sera were not effective for the monkey IPE cell culture. Conversely, the cells grew well in the medium with auto, bovine, or human serum. Human IPE cells grew exponentially by the described methods and reached to 60,000 cells after about 4-5 weeks. When we compared them by proliferation rate, IPE cells were less proliferative than RPE cells. The gene expression for melanogenesis and the amount of pigment in the IPE gradually decreased through successive passages. Transplantation has been tried for the treatment of age-related macular degeneration using RPE from fetus or from eye bank eyes. However, focal rejection may play an important role in the clinical results. The establishment of auto IPE cell transplantation may improve the problem of rejection. In the present study, we established auto IPE cell culture using auto serum. The cultured IPE cell showed pigment epithelial cell properties until around five passages in both human and monkey.

Animals↗

PubMedDate not supplied

Non-T cell disturbance causes the suppression of the autologous mixed lymphocyte reaction in patients with gastric carcinoma.

We investigated the accessory function of non-T cells to autoreactive T cells in autologous mixed lymphocyte reaction (AMLR) and clarified the cause of the suppression of autoreactivity in patients with gastric carcinoma. The response of T cells in the AMLR in gastric cancer patients was significantly suppressed compared with that in controls. In patients in whom the AMLR of the spleen was suppressed more than that of the peripheral blood, the degree of stimulation of non-T cells from the spleen was remarkably suppressed, on the other hand, in patients in whom AMLR of the peripheral blood was suppressed more than the spleen, the degree of stimulation from the peripheral blood was remarkably suppressed. The expression of HLA-DR antigens on non-T cells of gastric cancer patients was lower than that of controls. AMLR was considerably decreased in controls by the treatment non-T cells with anti-HLA-DR MoAb, but not in cancer patients. Treatment of non-T cells from the spleen of gastric cancer patients with IFN-gamma remarkably improved T cell proliferation in the AMLR. IFN-gamma also enhanced the expression of HLA-DR antigens on non-T cells. The disturbance of non-T cells was not biased to a specific population. These disturbances of non-T cells suppressed the AMLR independently of stage status. Therefore, the immunological abnormality of non-T cells manifested by reduced accessory function to autoreactive T cells may cause impaired immunological surveillance against tumors and permit cancer cell growth.

Antibodies, Monoclonal↗

PubMedDate not supplied

Polysaccharide preparation PSK augments the proliferation and cytotoxicity of tumor-infiltrating lymphocytes in vitro.

We have investigated whether or not polysaccharide preparation PSK directly augments the proliferation and cytotoxicity of tumor-infiltrating lymphocytes (TILs). TILs were separated from 10 patients with gastrointestinal cancer (5 gastric cancers, 3 colon cancers and 2 pancreatic cancers). TILs were cultured with IL-2 and PSK for 7 days. The DNA synthesis of TILs was augmented by incubation with 100 micrograms/ml of PSK, which was similar to serum level with oral administration of PSK in cancer patients. The effect of PSK in DNA synthesis was also found by elimination of non-T cells. Furthermore, we established TIL clones and examined the effect of PSK on TILs clones. The DNA synthesis was augmented by PSK in CD4 positive and CD8 positive TIL clones without non-T cells, suggesting that PSK acts directly on TILs. We examined the cytotoxic activities of TILs by the 4-h and 16-h 51Cr release assay. PSK did not affect the cytotoxic activity of TILs against autologous tumor cells and KATO-III cells in the 4h 51Cr release assay, whereas PSK induced high lysability of TILs against autologous tumor cells in the 16-h 51Cr release assay. We studied the ability of PSK to induce cytokines from TILs using a double chamber plate. The DNA synthesis of tumor cells was more suppressed by the mixed-tumor cell culture supernatants of TILs cultured with PSK, compared to that of TILs cultured without PSK. It is suggesting that PSK induced long term killing activity of TILs by induction of cytotoxic cytokines. Thus, PSK augmented the proliferative response of TILs without interaction of T cells and non-T cells and induced cytotoxic cytokines of TILs.

Cell Division↗

PubMedDate not supplied

In vitro augmentation of cytotoxic activity of peripheral blood lymphocytes and spleen cells of cancer patients by ubenimex.

Ubenimex is used for the immunotherapy of malignant diseases as a biological response modifier (BRM) and shows beneficial effects as an adjuvant treatment. In the present study, the in vitro effects of ubenimex on the cytotoxic activity of peripheral blood lymphocytes (PBL) and spleen cells of cancer patients and the mechanism of killer cell activation were investigated. Cytotoxic activity against K562, KATO-III and autologous tumor cells was augmented by in vitro sensitization with ubenimex (p < 0.05). The optimal concentration of ubenimex for induction of cytotoxic activity was 1 micrograms/ml, similar to serum levels after clinical oral administration. The major population of killer cells activated by ubenimex recognizing K562 was CD16+, and those recognizing KATO-III were mainly CDA+ or CD8(5) cels and CD16+ NK cells, while CDA5 or CD8+T cells comprised the majority of killer cells which showed autologous tumor-killing activity. Augmentation of the cytotoxic activity of mononuclear cells by ubenimex was blocked by both anti-IL-1 beta Ab and anti-IL-2 AB. However, the expression of IL-2 receptor (p55, p75) on effector cells was not altered. Ubenimex augmented not only NK activity but also autologous tumor killing activity of PBL and spleen cells via macrophage activation. These activities of ubenimex may be clinically beneficial as an adjuvant treatment.

Adjuvants, Immunologic↗

PubMedDate not supplied

Ubenimex treatment enhances the susceptibility of gastric cancer cell lines to lymphokine-activated killer cells.

We investigated the direct effects of ubenimex on the modification of gastric carcinoma cell lines' susceptibility to killer cells, and the mechanism of its action. The susceptibility of both MKN-45 cells and KATO-III cells to LAK cells was enhanced by treatment with ubenimex for 48 h (p < 0.05), and the optimal concentration for this effect was 10 micrograms/ml. The susceptibility of ubenimex treated KATO-III cells to CD3+ LAK cells, especially to those also expressing CD8, was enhanced. DNA synthesis of tumor cells was not impaired by treatment with ubenimex at all concentrations tested. The binding rate of LAK cells and ubenimex-treated KATO-III cells was similar to that between LAK cells and untreated KATO-III cells. Moreover, no alterations in the expression of any antigen related to mononuclear cell-binding to tumor cells were induced by ubenimex. Lysis or the inhibition of DNA synthesis of tumor cells by LAK cell supernatant was enhanced by ubenimex. These results suggested that the mechanism responsible for the augmentation of tumor cell susceptibility by ubenimex may be a result of the alteration of their sensitivity to some Iytic factors released by LAK cells. Thus ubenimex shows not only an indirect host-mediated anti-tumor activity but also a direct effect on tumor cells, modifying their susceptibility to killer cells, and this may explain why ubenimex shows beneficial clinical effects as an adjuvant treatment.

Adjuvants, Immunologic↗

PubMedDate not supplied

Aspiration cytology of malignant intraductal myoepithelioma of the breast. A case report.

The cytologic features of a fine needle aspiration biopsy of a malignant intraductal myoepithelioma of the breast are described. On cytology the tumor cells were shed in cohesive groups consisting of ill-defined polygonal and spindle cells. The latter, which had centrally located, cigar-shaped nuclei, showed a fascicular pattern. Despite cellular multilayering, there was a halo-like transparency around the nuclei, suggesting that many cells had clear or pale cytoplasm. Mild nuclear atypia was occasionally present. Mitotic figures were also observed. With immunostaining, clustered cells showed a diffuse positive reaction for alpha smooth muscle actin (alpha-SM-actin). The tumor cells proliferated intraductally, as in a conventional intraductal carcinoma with a comedo or solid pattern. Characteristically, zones of clear, polygonal cells were situated at the ductal periphery. Toward the center of each duct, tumor cells were transformed into nonclear cells, and some were further transformed into spindle cells that tended to form fascicles. Immunohistochemically, most of the tumor cells expressed alpha-SM-actin.

Biopsy, Needle↗

PubMedDate not supplied

Augmentation of lymphokine-activated killer cell activity by lentinan.

Lymphokine-activated killer (LAK) activity stimulated by interleukin 2 (IL-2) and/or lentinan was examined in the peripheral blood of 9 healthy subjects and 7 cancer patients. After 4 and 8 days culture, LAK killer activity stimulated by IL-2 and lentinan against autologous tumor and K562 cells was greater than that stimulated by IL-2 alone. The optimal concentration of lentinan for the generation of killer cells ranged from 25-500 ng/ml, a level which can be achieved in vivo by the administration of clinical doses of this agent. The expression of CD25 antigen, the alpha chain of the IL-2 receptor on the activated killer cells was increased by lentinan. Thus it was shown that LAK cells stimulated with IL-2 plus lentinan had strong cytotoxicity and might be useful as effector cells for adoptive immunotherapy.

Cytotoxicity, Immunologic↗