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Biomedical subjects

J Imanishi

Publications and source records attributed to J Imanishi.

16 recordsLinked to original sources

Expression of the cell surface antigen detected by the monoclonal antibody A7 in pancreatic carcinoma cell lines.

In a previous study, we used a murine monoclonal antibody, A7, against human colon carcinoma as a drug-carrier to treat colorectal cancer. In the present study, we found that MAb A7 also reacted immunohistochemically with 73% of human pancreatic carcinoma cell lines, with the A7 antigen mainly being detected on the cell surface. However, the A7 antigen was found in only 9% of the spent media of these human pancreatic carcinoma cell lines by ELISA. On the other hand, the positive incidence of CA19-9, POA, ferritin, CEA, DU-PAN-2 and SLX in those spent media was 100%, 64%, 64%, 55%, 55% and 36%, respectively. These results suggest that the A7 antigen may only rarely be shed into the sera of pancreatic cancer patients, in which case MAb A7 could be a suitable drug-carrier in targeting chemotherapy for pancreatic cancer patients.

Antibodies, Monoclonal

Induction of cytokines in human peripheral blood mononuclear cells by mycoplasmas.

Various species of mycoplasmas were tested for their ability to induce cytokine production in human peripheral blood mononuclear cells (PBMC). Human PBMC were incubated with Mycoplasma pneumoniae, M. hyorhinis, M. arginini, M. salivarium, M. orale, M. gallisepticum or A. laidlawii for 48 hr, and the activities of interleukin-1 beta (IL-1 beta), IL-2, IL-4, IL-6, tumor necrosis factor-alpha (TNF-alpha) and interferon (IFN) in the supernatants were determined by ELISA or bioassay. All mycoplasma species induced IL-1 beta, IL-6 and TNF-alpha, although IL-2 was induced only by M. pneumoniae. IFN was induced by 5 of the 7 species, and the IFN produced was antigenically confirmed to be mainly IFN-alpha. On the other hand, mycoplasma-stimulated cultures did not contain detectable amounts of IFN-beta and IL-4 activities. Furthermore, the cytokines were induced by mycoplasmal contaminating cells in human PBMC as well as by mycoplasma alone. These results suggest that many kinds of cytokines induced by mycoplasma contamination in cell culture affect immunological experiments in vitro.

Biological Assay

Distribution of two types of infiltrating helper T cells among rat renal allografts, spleen, peripheral blood, and regional lymph node cells.

Cytokine production by graft-infiltrating cells (GIC) of helper T cell (Th) subtypes were investigated in rat kidney allograft compared to those infiltrating the spleen, those in peripheral blood, and in regional lymph nodes. The relative proportion of OX-22 positive cells (Th type 1) and the W3/25-positive cells (Th) of GIC was 49.4 +/- 2.1% on day 3 and 52.7 +/- 2.2% on day 6, whereas those in spleen cells was 80.3 +/- 4.1% (p less than 0.05) and 95.5 +/- 2.5% (p less than 0.01), respectively. GIC produced more B cell-stimulating factor 2 (BSF-2, 106.3 +/- 8.2 U/ml) when compared to spleen cells (15.9 +/- 4.6 U/ml; p less than 0.01), peripheral blood mononuclear cells (4.2 +/- 1.0 U/ml; p less than 0.01) or lymph node cells (24.9 +/- 4.0 U/ml; p less than 0.01) upon stimulation with donor BN lymphocytes in vitro. However, GIC produced less interleukin 2 (IL-2, less than 1.0 U/ml) and IL-3 (less than 1.0 U/ml) than produced by spleen cells (5.1 +/- 0.9 U/ml, p less than 0.05, and 10.5 +/- 2.3 U/ml, p less than 0.01, respectively) or lymph node cells (4.5 +/- 0.4 U/ml, p less than 0.01; 23.5 +/- 3.1 U/ml, p less than 0.01, respectively). These results demonstrate that the subtype of Th cells which produce BSF-2 migrates selectively to allografts.

Animals

Detection of influenza B virus in throat swabs using the polymerase chain reaction.

An assay protocol based on exploiting the polymerase chain reaction (PCR) for the direct detection of influenza B virus in throat swabs is described. By the use of PCR with nested primers, it was possible to detect the virus in throat swabs. Dilution experiments showed that as little as 1 plaque forming unit of virus was sufficient for detecting the HA gene by the PCR. All throat swab samples from which influenza B virus had been isolated by conventional methods were also positive by the PCR method.

Base Sequence

[Bactericidal effects of macrophages of mice treated with interferon].

The preparations of interferon or virus-inhibiting factor produced in L cell (L-IF) and mouse brain (MB-IF) enhanced the killing of Staphylococcus aureus (S.a.) by the mouse peritoneal macrophage. The L-IF, heat-inactivated at 80 degrees or 60 degrees for 30 min., and mock L-IF could not enhance the killing of S.a. The heterologous human and rabbit interferon preparations didn't enhance the bactericidal activity of macrophage. The L-IF didn't have any effect on the release of lysozyme from the macrophages.

Animals

Effects of interferon preparations on rabbit corneal xenograft.

High doses of rabbit interferon (2 X 10(6) and 2 X 10(5) units/ml, a drop of about 0.1 ml administered topically into the eye twice daily) suppressed the rejection of rabbit corneal xenograft, whereas a low dose (2 X 10(3) units/ml) enhanced it, However, neither heat-inactivated rabbit interferon nor mouse L cell interferon showed any effects on rabbit corneal grafts.

Animals

Inhibition of macrophage migration by virus-induced interferon preparations.

It was found that a preparation of mouse L cell interferon induced by Newcastle disease virus (NDV) possessed not only interferon activity but also inhibitory activity upon migration of guinea pig peritoneal macrophages (MIF activity). These activities were also observed in a preparation of human leukocyte interferon induced by NDV. The interferon and MIF activities shared common characteristics in the dose response, time course of in vitro production, thermal stability, sensitivity to trypsin and periodate, and elution pattern in CM-Sephadex column chromatography. However, gel filtration pattern with Sephadex G-100 showed two separate peaks. Fractions collected from the first peak, corresponding to a molecular weight of about 45 000, had only the MIF activity, while those collected from the second peak, corresponding to a molecular weight of about 30 000, had both the interferon and MIF activities. A preparation of mouse brain interferon induced by Japanese encephalitis virus had a much weaker MIF activity than the L cell interferon, although these preparations were equal in interferon activity (5000 units/ml).

Animals

Phagocytosis-enhancing effect of human leukocyte interferon preparation of human peripheral monocytes in vitro.

It was found that the phagocytosis of human peripheral monocytes was enhanced by human leukocyte interferon preparations. This activity showed species-specificity and a positive correlation between interferon titer and phagocytic activity. When human monocytes were treated by interferon, the pahagocytic activity was enhanced. But when interferon was added to the latex, the enhancement was not observed. The interferon preparation did not only increase the number of phagocytic cells, but also enhanced the degree of phagocytosis in individual cells. The factor responsible for the enhancing effect was inactivated by trypsin, but was not inhibited by actinomycin D.

Animals

Preliminary report on the clinical use of human leukocyte interferon in neuroblastoma.

The effectiveness of human leukocyte interferon (IF) injections on a female patient, 21 years old, with stage IV neuroblastoma was observed. IF (30 X 10(4) units) injected every second day intratumorally or around the tumor tissue rapidly reduced the tumor size. However, systemic administration of 300 x 10(4) units of IF by im injection showed no beneficial effects. Our results suggest that a high IF level in tumor tissue may be necessary to bring about tumor reduction.

Adult