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Biomedical subjects

M Hakoda

Publications and source records attributed to M Hakoda.

63 records · Page 4Linked to original sources
PubMed1988

Detection of soluble tumor-associated antigens in sera and effusions using novel monoclonal antibodies, KL-3 and KL-6, against lung adenocarcinoma.

Two novel monoclonal antibodies, KL-3 (IgM) and KL-6 (IgG1), which can detect soluble antigens in sera and effusions (molecular weights greater than 1,000 K) were produced against human pulmonary adenocarcinoma VMRC-LCR cells. KL-3 and KL-6 antibodies reacted with asialo- and sialo-carbohydrate antigenic determinants, respectively. Both carbohydrate epitopes appear, from competitive inhibition studies, to be different from Lex, Ley, sialyl Lea and sialyl Lexi which were recognized with FH2, AH6, NS19-9 and FH6 antibodies, respectively. Using an enzyme linked immunosorbent assay, elevated KL-6 antigen levels were frequently observed in the sera of patients with lung adenocarcinoma [52% (17/33)], pancreatic cancer [44% (4/9)] and breast cancer [40% (8/20)], but infrequently in the sera of patients with lung squamous cell carcinoma [18% (4/22)], lung small cell carcinoma [8% (1/13)], gastric cancer [0% (0/19)], colorectal cancer [0% (0/8)] and hepatocellular cancer [13% (1/8)]. The levels and positive rates of serum KL-6 antigen increased with the progression of clinical stage of lung adenocarcinoma. In pleural effusions, the prevalences of lung adenocarcinoma cases with elevated levels of KL-3 and KL-6 antigens were 76% (13/17) and 82% (14/17), respectively. These monoclonal antibodies can define novel soluble antigens in sera and effusions which could be useful in tumor diagnoses and for monitoring tumor progression.

Adenocarcinoma↗
PubMed1986

Cryopreservation of human lymphocytes for assessment of lymphocyte subsets and natural killer cytotoxicity.

Cryopreservation of lymphocytes has become increasingly important, especially when the cells are to be used in retrospective studies of selected and dwindling populations, such as A-bomb survivors. This report describes an efficient method for cryopreservation of human lymphocytes which does not significantly alter various immunological characteristics of these cells. The proportions of Leu-1+ cells (T cells), Leu-2a+ cells (suppressor-cytotoxic T cells), Leu-3a+ cells (helper-inducer T cells), HLA-DR+ cells, Mo2+ cells (monocytes), B1+ cells (B cells), and Leu-7+ cells (natural killer (NK) cells), as determined by monoclonal antibodies, were found to be stable following cryopreservation. NK cell activity against K-562 target cells showed a 40-60% decrease immediately after thawing, but recovered to approximate pre-freezing levels after preincubation for 18 h. Neither lymphocyte subsets nor cell viability significantly changed following preincubation after cryopreservation. However, the ratio of cells binding to K-562 cells increased after this preincubation and may account for the observed recovery of NK cell activity. NK cell activity remained relatively stable up to 14 months of storage which confirms that freezing damage depends on the freezing process rather than on the duration of cryopreservation.

Antibodies, Monoclonal↗
PubMed1985

Monoclonal antibodies to human squamous cell carcinoma of the lung and their application to tumor diagnosis.

Three immunoglobulin G1 monoclonal antibodies, LuCa2, LuCa3, and LuCa4, were produced by fusing murine myeloma NS1 cells with splenocytes obtained from a BALB/c mouse immunized with SK-MES1 cells derived from human squamous cell carcinoma of the lung. These three monoclonal antibodies were shown to recognize different protein antigens on SK-MES1 cells by indirect immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. While the pattern of cell line distribution of antigens recognized by these antibodies was not tumor type specific, their reactivity with tissue and pleural effusion was much more informative than with cell lines. The presence of target antigens in vivo was analyzed by immunoperoxidase staining of frozen tissue sections and immunofluorescence staining of tumor cells in pleural effusions. LuCa2 antibody was reactive with lung squamous carcinoma and adenocarcinoma tumor tissues and pleural effusions, but only infrequently with those of small cell carcinoma. This antibody was also reactive with many tumor tissues from other organs as well as with various normal tissues, including alveoli and bronchus. LuCa3 and LuCa4 antibodies reacted with lung squamous carcinoma in tissues and pleural effusions, but not with lung adenocarcinoma nor with small cell carcinoma. These two antibodies reacted only weakly with normal squamous tissues of the esophagus, skin, and cervix uteri, but not with various other normal tissues. Moreover, LuCa3 had weak reactivity with squamous cell carcinoma tissue of tongue and esophagus, whereas LuCa4 had no reactivity with nonpulmonary tumor tissues. LuCa3 and LuCa4 antibodies should be of clinical interest, because our data suggest that these antibodies may be potentially useful for the diagnosis of the histological type of lung tumor cells in both cancer tissue and pleural effusions.

Antibodies, Monoclonal↗
PubMedDate not supplied

Formation of DNA strand breaks by D-penicillamine and bucillamine in human lymphocytes.

DNA strand breakage by D-penicillamine and bucillamine, anti-rheumatic agents with thiol residues was evaluated in DNA unwinding assays. When incubating human peripheral blood lymphocytes with D-penicillamine or bucillamine in the presence of 8 microM CuSO4, numerous DNA strand breaks occurred and those depended on the production of hydrogen peroxide and were completely blocked in the presence of catalase. This phenomenon was reversible, and fragmented DNA was repaired in 8 to 24 h. Significant decreases in cellular NAD levels were observed at concentrations of D-penicillamine or bucillamine which could damage DNA. As extensive depletion of cellular NAD functionally inactivates lymphocytes, the formation of DNA strand breaks may have a role in the immunomodulating action of these anti-rheumatic drugs.

Arthritis, Rheumatoid↗
PubMedDate not supplied

Development of a method to analyze single cell activity by using dielectrophoretic levitation.

In cell fusion and genetic recombination, although the activity of single cells is extremely important, there is no method to analyze single cell activity. Development of a quick analyzing method for single cell activity is desired in various fields. Dielectrophoresis (DEP) refers to the force exerted on the induced dipole moment of an uncharged dielectric and/or conductive particle by a nonuniform electric field. By applying DEP, we obtained experimentally a relationship between the cell activity and the dielectric property, Re[K(omega)], and examined how to evaluate the single cell activity by measuring Re[K(omega)] of a single cell. A cone and plate electrode geometry was adapted in order to achieve the feedback-controlled DEP levitation. The single cell is exposed to a nonuniform field induced by the cone and plate electrode, and a more polarizable cell is moved to the direction of the cone electrode by the DEP force. The cell settles in the position where the DEP force and gravity are balanced by controlling applied voltage. This settled position, measured on the center axis of the cone electrode, depended on the dielectric constant of the cell. From these results, the relationship between the specific growth rates in cell growth phase and the dielectric properties Re[K(omega)] was obtained. Furthermore, the effect on the cell activity of various stresses, such as concentration of carbon dioxide, temperature, etc., was examined.

Animals↗