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Biomedical subjects

H Tsurumi

Publications and source records attributed to H Tsurumi.

At least 55 records · Page 3Linked to original sources

Enhanced lymphatic delivery of monoclonal antibody following OK432 pretreatment.

The effect of OK432 on the lymphatic delivery of monoclonal antibody (Mab) was investigated by injecting [125I]-Mab A7 into BALB/c mice pre-treated with OK432, and measuring the radioactivity in the regional lymph nodes. The [125I]-Mab A7, when administered subcutaneously to the foot pad, preferentially accumulated in the ipsilateral popliteal and para-aortic lymph nodes. Treatment with OK432 prior to antibody injection significantly enhanced the accumulation of Mab A7 in these regional lymph nodes. These findings suggest that pretreatment with OK432 may constitute a promising method of enhancing the lymphatic delivery of Mab, and improving the efficacy of therapy directed against lymphatic malignancies.

Animals↗

The combined effects of all-trans retinoic acid and granulocyte colony-stimulating factor as a differentiation induction therapy for acute promyelocytic leukemia.

A 61-year-old male with acute promyelocytic leukemia (APL) had been in complete remission for the previous 15 months, but his APL relapsed with neutropenia. Although promyelocytes in bone marrow were reduced after administration of 60 mg all-trans retinoic acid (ATRA) daily, myelocytes were predominant on the myelogram and neutropenia did not recover. By adding 75 micrograms of granulocyte colony-stimulating factor (G-CSF) daily, neutrophils accounted for 35.0-55.5% of the myelogram, and the peripheral neutrophil count rose dramatically. Such morphological differentiation of myeloid series was also ascertained in terms of their functions of both neutrophil alkaline phosphatase activity and active oxygen producing capacity. This case supports the concept that G-CSF accelerates ATRA-induced neutrophilic differentiation of blast cells in APL.

Alkaline Phosphatase↗

Differentiation induction of human promyelocytic leukemia cells by acyclic retinoid (polyprenoic acid).

Acyclic retinoid (all-trans-3,7,11,15-tetramethyl-2,4,6,10,14-hexadecapentaenoic acid) has a slightly different structure from all-trans retinoic acid (ATRA), while it binds cellular retinoic acid-binding protein with a similar binding affinity to that of ATRA. We studied the in vitro efficacy of acyclic retinoid for the differentiation induction of human promyelocyte-derived HL-60 cell line and primary cultured blast cells obtained from 8 patients with acute non-lymphocytic leukemia (ANLL) including 3 acute promyelocytic leukemia (APL) patients. HL-60 cells and ANLL cells were incubated with or without retinoids for 5 days. Acyclic retinoid induced the differentiation of HL-60 cells and APL cells at 10(-6) mol/l, while ATRA induced differentiation at 10(-7) mol/l. These concentrations were well below those that affected cell growth and viability. Although ATRA has an excellent capacity for differentiation induction of HL-60 and APL cells, it is also known to have severe, sometimes fatal, adverse effects, including retinoic acid syndrome. In contrast, acyclic retinoid is reported to have a much wider safety margin than that of ATRA. A clinical trial of acyclic retinoid for the differentiation induction therapy of APL may be worthwhile.

Adolescent↗

Flow cytometric determination of active oxygen (hydroperoxide) produced by peripheral blood neutrophils in patients with hematological disorders.

We analyzed active oxygen (hydroperoxide; H2O2) production by peripheral neutrophils in various hematological diseases by flow cytometry. One hundred microliters of heparinized fresh blood was sequentially incubated at 37 degrees C with 2',7'-dichlorofluorescein diacetate and with or without phorbol myristate acetate (PMA). After hemolysis, the pelleted white blood cells were subjected to flow cytometry, and the neutrophil fraction was gated on the cytogram. Production of H2O2 by the fraction was estimated by determining the increase in the relative intensity of fluorescence emitted from the fraction in response to stimulation by PMA. In controlled chronic myelogenous leukemia (CML) (WBC < 1 x 10(10)/1), H2O2 production was normal, while in uncontrolled CML (WBC > or = 1 x 10(10)/1), it was reduced. In myelodysplastic syndrome (MDS), H2O2 production was also reduced, but no significant difference was observed among FAB classification disease types in MDS patients. In untreated acute non-lymphocytic leukemia (ANLL), H2O2 production was reduced, while in the complete remission stage of ANLL, its level was normal, suggesting recovery from normal clones. In aplastic anemia, the H2O2 production level was normal. Steroid therapy might be responsible for the reduction of H2O2 production in non-Hodgkin's lymphoma and multiple myeloma. The production of H2O2 is closely related to the oxygen-dependent bactericidal activity of neutrophils, and, hence, can be utilized as an index to indicate susceptibility to infection. This neutrophil function can be determined easily in ordinary clinical facilities by using flow cytometry, and care should be taken to prevent infection when H2O2 production is reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

Local administration of monoclonal antibody-drug conjugate: a new strategy to reduce the local recurrence of colorectal cancer.

This report investigates the application of monoclonal antibody A7 and its drug conjugate in locally controlling colorectal cancer. The experimental protocol consisted of local retention, lymphatic delivery, normal organ distribution, systemic toxicity, and tumoricidal effects. When 125I-labeled monoclonal antibody (Mab) A7 was injected into the pelvis and the thigh of Balb/c mice, a high local retention unrelated to antigen-antibody interaction was observed at the injected site for 24 h after injection. An analysis of local retension properties related to antigen-antibody interaction, conducted by intratumorally or peritumorally injecting 125I-Mab A7 into the tumor-bearing athymic nude mice, revealed a significantly higher tumor localization of Mab A7 in comparison to i.v. injection. 125I-Mab A7 accumulated to a great extent in the ipsilateral regional lymph node but not in the contralateral regional lymph node. Normal organ accumulation of Mab A7 was lower in the locally injected group than in the i.v. injected group. Intratumoral injection of Mab A7-neocarzinostatin (A7-NCS) led to the complete remission of established tumor in 5 of 6 antigen-positive xenograft-bearing mice but exhibited a complete remission in only 1 of 6 antigen-negative xenograft-bearing mice. A single local injection of A7-NCS inhibited tumor development in 12 of 16 and 5 of 15 antigen-positive tumor-bearing mice and antigen-negative tumor-bearing mice, respectively, whereas neither a systemic injection of A7-NCS and NCS nor a local injection of NCS and saline had a notable inhibitory effect on tumor development. Systemic toxicity of NCS was markedly reduced when it was locally administered in the antibody-conjugated form. These findings indicate that local injection of immunoconjugate is a promising new field for controlling the local recurrence of colorectal cancer.

Animals↗

Adult T-cell leukemia developing during immunosuppressive treatment in a renal transplant recipient.

We report a case of a 32-year-old male, an asymptomatic carrier of human T-cell leukemia virus type 1 (HTLV-1), who underwent a renal transplantation and developed adult T-cell leukemia (ATL) during the course of posttransplant immunosuppressive treatment. He was treated with combination chemotherapies consisting of cyclophosphamide, vincristine, doxorubicin, prednisolone, cisplatin, cytosine arabinoside, etoposide, and methyl-prednisolone, without any improvement. Bestrabucil (KM2210), a conjugate of chlorambucil and estradiol, was administered as an alternative therapy; this therapy successfully suppressed his leukemic cell growth, and partial remission was achieved. Posttransplant immunosuppressive therapy with prednisolone, mizoribine, and cyclosporin A might have been the predominant cause of the transition from an asymptomatic HTLV-1 infection to overt ATL. A careful approach is required with HTLV-1 asymptomatic carriers who need organ transplantation followed by immunosuppressive treatment.

Adult↗

Spontaneous bacterial peritonitis due to Clostridium perfringens in a patient with liver cirrhosis and pure red cell aplasia.

A 63-year-old man with decompensated liver cirrhosis and pure red cell aplasia complained of pyrexia, abdominal distention and abdominal pain. A diagnosis of spontaneous bacterial peritonitis (SBP), Conn's syndrome, was made upon the isolation of an anaerobe Clostridium perfringens from both ascitic fluid and peripheral blood. The bacteria were found to be susceptible to piperacillin, and administration of the antimicrobial agent markedly improved his SBP. The anaerobes should be kept in mind as one of the possible pathogens of SBP, although anaerobic infection has been reported to be quite rare in the disease.

Clostridium Infections↗

Enhanced tumor localization of monoclonal antibody by treatment with kininase II inhibitor and angiotensin II.

The effect of kininase II inhibitor, enalapril, on the delivery of monoclonal antibody A7 to the targeted tumor was investigated using athymic mice bearing human colon cancer, SW1116. Enalapril alone, which enhances tumor vascular permeability through the kinin-generating cascade, did not increase the uptake of 125I-labeled A7 (125I-A7) in SW1116 due to the systemic hypotension induced by its inhibitory effect on angiotensin converting enzyme. However, with combined angiotensin II (AT-II) and enalapril treatment, a 2-fold increase in the accumulation of 125I-A7 was seen when compared to A7 alone. This marked increase was presumably due to increased tumor vascular permeability induced by enalapril combined with the absence of hypotension due to the actions of AT-II. This approach might be useful in radioimmunodetection and immunotargeting chemotherapy using monoclonal antibody.

Angiotensin II↗

Efficacy and specificity of a monoclonal antibody-drug conjugate in chemotherapy by intratumoral injection.

The murine monoclonal antibody (Mab) A7 conjugated to neocarzinostatin (A7-NCS) was injected intratumorally (IT) into tumor bearing nude mice. Its pharmacokinetics and tumoricidal effects were compared in the high, moderate and low antigen expressing xenograft for SW1116, WiDr and KB tumor-bearing nude mice, respectively. When injected IT into nude mice, [125I]A7-NCS was retained in the tumors according to the degree of antigen expression; it was also disseminated into the blood inverse proportion to the antigen expression. Addition of an excess amount of Mab A7 reduced [125I]-A7-NCS accumulation in SW1116 xenograft and elevated the [125I]A7-NCS concentration in the circulation. Complete tumor reduction was found in all 5 mice with SW1116 tumor, and 2 of 5 mice with WiDr tumor. However, only incomplete tumor suppression was observed in mice with the KB tumor. The significant tumor reduction in SW1116 bearing nude mice was attenuated when excess of Mab A7 was simultaneously administered with A7-NCS. These findings indicate that A7-NCS was localized in the target tumors and exerted its tumoricidal effects depending on the degree of antigen-antibody interaction when administered IT. Thus, A7-NCS can be used successfully in vivo for local therapy, auguring new and promising applications for local cancer therapy.

Animals↗

[Flow cytometric determination of active oxygen produced by neutrophils in patients with inflammatory diseases].

We investigated active oxygen (H2O2) production by neutrophils in patients with inflammatory diseases such as connective tissue disease and respiratory tract infection. The analysis was done by flow cytometry using as small volume of whole-blood as 100 microliters. H2O2 production as well as C-reactive protein (CRP) were increased in connective tissue diseases, and was decreased after steroid therapy. In a case of neuro-Behçet's disease, changes in H2O2 production was observed in agreement with those in clinical symptoms such as gait disturbance. H2O2 production as well as CRP and neutrophil count were increased in acute respiratory tract infection, but in chronic patients H2O2 production alone was rather reduced. In stages of enhanced H2O2 production, tissue damage or inflammation may exist, the degree of which seems to be well reflected by H2O2 production. During stages of impaired H2O2 production, care should be taken to prevent infections. Using flow cytometry, H2O2 production can be easily determined as one of functions of neutrophils.

C-Reactive Protein↗

CD30/Ki-1-positive anaplastic large cell lymphoma preceded by Hodgkin's disease.

A 59-year-old man was initially diagnosed as having Hodgkin's disease, nodular sclerosis type, and complete remission was achieved after combination chemotherapy. One year later, he developed a high fever and recurrence of the Hodgkin's disease was diagnosed. Salvage chemotherapy was ineffective, and the patient died. Autopsy specimens showed infiltration of lymphoma cells into multiple organs. Lymph nodes showed characteristics of non-Hodgkin's lymphoma, with expansion of anaplastic large cells; this differed from the histological features at initial diagnosis. Immunohistochemical staining was positive for CD30/Ki-1, but negative for CD15 (LeuM1). These findings were compatible with Ki-1 lymphoma, suggesting that this may be a case of CD30/Ki-1 lymphoma preceded by Hodgkin's disease and that a certain proportion of Ki-1 lymphomas and Hodgkin's disease may share the same cellular origin.

Antigens, CD↗

Chemical engineering of the monoclonal antibody A7 by polyethylene glycol for targeting cancer chemotherapy.

The murine monoclonal antibody A7 (Mab A7) against human colon cancer was chemically modified with methoxypolyethylene glycol (PEG) (Mr 5000). A high substitution of PEG molecules on Mab A7 produced a progressive reduction in antibody-binding activity. The pharmacokinetic and immunological properties of PEG-modified monoclonal antibody A7 (Mab A7) and the PEG-modified F(ab')2 fragment, which retained their antibody-binding activity, were assessed and compared with the parent Mab A7 and the parent F(ab')2 fragment. Blood clearance of PEG-modified antibodies appeared to be diminished by PEG modification and was fitted by a two-compartment model. Low PEG-substituted Mab A7 showed less organ uptake in the liver and spleen and similar uptake in the lung and kidney, compared with the parent Mab A7. PEG-F(ab')2 showed less uptake in the liver and kidney. Both preparations exhibited less tissue:blood ratios in all resected organs as compared with parent antibodies. Tumor localization was enhanced by PEG modification for the F(ab')2 fragment, but not by PEG modification for the whole Mab A7. Multiple i.v. administration of PEG-modified antibody to rabbit did not appear to elicit a measurable immune response to the antibody portion of the conjugate. In conclusion, PEG-modified antibodies are promising reagents as drug carriers to the target tumor.

Animals↗

A case of leiomyoblastoma (epithelioid leiomyosarcoma) of the greater omentum.

A 59-year-old male complained of a palpable abdominal mass which was revealed to be a primary omental tumor by means of abdominal ultrasonography, computed tomography, angiography and laparoscopy. Histological examinations of the surgically resected tumor further disclosed leiomyoblastoma with positive stainings of both vimentin and desmin, markers for mesenchymal cells and for muscle cells, respectively. He has been well for 2 years since resection, without any relapse or distant metastasis of the tumor. Leiomyoblastoma of the greater omentum is very rare, and is important to distinguish from extraluminal tumor of the abdomen.

Angiography↗

Comparative pharmacokinetic properties of murine monoclonal antibody A7 modified with neocarzinostatin, dextran and polyethylene glycol.

The murine monoclonal antibody A7 (Mab A7) was chemically modified with several macromolecules: dextran, polyethylene glycol and the anti-cancer polypeptide neocarzinostatin. The pharmacokinetic properties of the combinations were subsequently examined. Radioimmunoassay revealed that all preparations retained their antigen-binding activities. The Mab A7-neocarzinostatin conjugate was cleared from the blood circulation with a kinetic pattern almost identical to that of the parent Mab A7. Of the three preparations, Mab A7-dextran (A7-Dx) was removed the most rapidly from the circulation. Mab A7-polyethylene glycol (A7-PEG) exhibited the slowest blood clearance curve, with twice the half life of the parent Mab A7 in the circulation. In normal organ distributions, A7-Dx exhibited the highest liver, spleen and kidney uptake, and A7-PEG showed the lowest uptake, when expressed as tissue:blood ratio. Although A7-Dx exhibited lower tumor uptake, there was no significant difference among the three conjugates in tumor-bearing nude mice. A7-PEG seems to be a good candidate for targeted cancer therapy using antibody due to its high blood retention but low normal organ uptake.

Animals↗

Pharmacokinetic analysis of the monoclonal antibody A7-neocarzinostatin conjugate administered to nude mice.

The pharmacokinetics of a disulfide linked conjugate of a murine monoclonal antibody A7 with neocarzinostatin (A7-NCS) was studied following its intravenous administration to nude mice. Disappearance of the conjugate from the circulation was biphasic: an early rapid phase was followed by a much slower phase. The conjugate was removed from the blood circulation with a half-life of 12 hr, showing nearly the same kinetics as the free antibody. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the disulfide linkage in A7-NCS was stable at least for 48 hr after administration of the conjugate to nude mice. The conjugate concentration in a human colon cancer SW1116 derived tumor reached maximum at 24 hr after injection and remained high for an additional 24 hr. The passive hemagglutination inhibition assay revealed that NCS in the conjugated form can be efficiently delivered to the target tissue. The present report indicates that A7-NCS was sufficiently stable in circulation to reach the target tumor without releasing NCS.

Animals↗