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Biomedical subjects

E Azuma

Publications and source records attributed to E Azuma.

At least 91 records · Page 5Linked to original sources

Neonatal alloimmune thrombocytopenic purpura associated with sensitization against the platelet-specific antigen Yuk(a).

We report a Japanese newborn who developed alloimmune thrombocytopenia by the antibodies to the newly discovered platelet antigen Yuk(a). The infant recovered uneventfully in 10 days without specific treatment. Antiplatelet alloantibodies in the patient were IgG class detected by mixed passive hemagglutination (MPHA). Family study showed that Yuk(a) antigen was inherited as an autosomal dominant trait. Cases with Yuk(a)-associated alloimmune thrombocytopenia are reviewed.

Antigens, Human Platelet↗

G-CSF enhanced granulocyte production in a child with severe neutropenia in the setting of fatal virus-associated hemophagocytic syndrome.

A 14-year-old boy with fatal varicella zoster virus-associated hemophagocytic syndrome (VAHS) was treated with recombinant human granulocyte colony-stimulating factor (G-CSF) based on the finding that the patient had severe neutropenia and possible bacterial superinfection. Support for the G-CSF therapy in VAHS is provided by the recent reports that G-CSF is relatively specific for the granulocyte lineage; it would not activate mature monocyte/macrophage/histiocyte lineage in VAHS, where the most striking morphologic feature is histiocytic hyperplasia with hemophagocytosis. He responded well to G-CSF with an elevation of neutrophil counts. There were no effects on other blood cells. The result indicates that G-CSF is useful to increase granulocyte production in severe neutropenia, even in the setting of fatal VAHS.

Adolescent↗

Leukemia-specific serum from a child showing an immunofluorescent pattern distinct from J-5 monoclonal antibody directed for CD10 (common ALL antigen).

Leukemia-specific human antibody was detected in a child with acute lymphoblastic leukemia (ALL) treated with chemoimmunotherapy. Chemoimmunotherapy consists of standard chemotherapy and subcutaneous injections of irradiated ALL cells with a biological response modifier. This ALL-specific serum reacted in 60 out of 67 (89.5%) children with ALL and was not reactive with normal cells. Furthermore, this ALL-specific serum showed a different immunofluorescent pattern on dual staining as compared with J-5 monoclonal antibody directed for common ALL antigen (CALLA; CD10). J-5 did not block the reactivity of ALL-specific serum, and vice versa, when CD10-positive ALL cell lines were used as targets. These findings suggest the possibility that there exists an ALL-specific antigen(s) which is different from CALLA and that this antigen(s) elicits a tumor-specific antibody response.

Antibodies, Monoclonal↗

Autologous tumor-specific cytotoxic T-lymphocytes in a child with neuroblastoma.

Activation of peripheral blood lymphocytes from a neuroblastoma patient by co-cultivation with autologous neuroblastoma cells in a mixed lymphocyte-tumor cell culture (A-MLTC) resulted in the generation of cytotoxic activity against the autologous neuroblastoma cell line HNB-MS. A-MLTC was set up in the presence of recombinant human interleukin-2 (IL-2). HNB-MS stimulator was treated with recombinant human interferon-gamma (IFN-gamma) prior to A-MLTC. CTL generated in short-term culture effectively lysed HNB-MS, while they had no effect on an Epstein-Barr virus transformed autologous B-cell line EB-MS. Moreover, CTL lysed 3 different allogeneic neuroblastoma cell lines, but not a rhabdomyosarcoma cell line RBB. Recombinant human tumor necrosis factor-alpha (TNF-alpha) and interleukin-4 (IL-4) enhanced and suppressed CTL generation, respectively, when added to the A-MLTC from the beginning of culture. CD3+ CD4- CD8+ T cells were the major anti-tumor effectors. Furthermore, 111indium-labeled CTL clearly accumulated in metastatic sites. These results indicate that CTL can be used for adoptive immunotherapy in neuroblastoma.

Abdominal Neoplasms↗

Use of lymphokine-activated killer cells to prevent bone marrow graft rejection and lethal graft-vs-host disease.

Prompted by our recent finding that lymphokine-activated killer (LAK) cells mediate both veto and natural suppression, we tested the ability of adoptively transferred LAK cells to block two in vivo alloreactions which complicate bone marrow transplantation: resistance to transplanted allogeneic bone marrow cells, and lethal graft-vs-host disease. Adoptive transfer of either donor type B6D2 or recipient-type B6 lymphokine-activated bone marrow cells, cells found to have strong LAK activity, abrogated or inhibited the resistance of irradiated B6 mice to both B6D2 marrow and third party-unrelated C3H marrow as measured by CFU in spleen on day 7. The ability of lymphokine-activated bone marrow cells to abrogate allogeneic resistance was eliminated by C lysis depletion of cells expressing asialo-GM1, NK1.1, and, to a variable degree, Thy-1, but not by depletion of cells expressing Lyt-2, indicating that the responsible cells had a LAK cell phenotype. Similar findings were obtained by using splenic LAK cells generated by 3 to 7 days of culture with rIL-2. Demonstration that allogeneic resistance could be blocked by a cloned LAK cell line provided direct evidence that LAK cells inhibit allogeneic resistance. In addition to inhibiting allogeneic resistance, adoptively transferred recipient-type LAK cells prevented lethal graft-vs-host disease, and permitted long term engraftment of allogeneic marrow. Irradiation prevented LAK cell inhibition of both allogeneic resistance and lethal graft-vs-host disease. These findings suggest that adoptive immunotherapy with LAK cells may prove useful in preventing graft rejection and graft-versus-host disease in human bone marrow transplant recipients.

Animals↗

Discontinuing therapy in childhood acute lymphoblastic leukemia treated with a chemoimmunotherapy protocol.

We examined the results of discontinuing therapy in Japanese children with acute lymphoblastic leukemia. Of the 209 patients in the chemoimmunotherapy study, 120 (57.4%) had all chemotherapy stopped after 3 years of complete remission, and 72 (34.4%) reached the point of discontinuing immunotherapy after 5 years of complete remission. Of the 120 children removed from chemotherapy, 14 (11.7%) have relapsed, mainly in the extramedullary sites (5: testis, 5: bone marrow, 3: central nervous system, 1: bone); relapses occurred 1-23 months after cessation of chemotherapy (median 11 months). Boys had higher post-chemotherapy relapse rate than girls (0.21 versus 0.08, P less than 0.05). None of the 72 children removed from immunotherapy have yet relapsed. Long-term remission and possibly cure can be expected in approximately one-half of newly diagnosed Japanese patients. Although the active immunotherapy had no beneficial effect on the overall outcome for leukemic children, it could be of benefit to the elimination of bone marrow relapses after cessation of chemotherapy.

Antineoplastic Agents↗

Role of lymphokine-activated killer cells as mediators of veto and natural suppression.

Fresh bone marrow cells have veto activity but little if any NK activity. By contrast, lymphokine-activated bone marrow cells have potent natural suppressor as well as veto activity, and also have cytolytic activity characteristic of lymphokine-activated killer cells. Veto activity of fresh bone marrow cells is eliminated by 9 Gy irradiation and by depletion of cells expressing Qa-2, but is unaffected by removal of cells expressing Thy-1, Qa-5, Ly-5, or asialo GM1. By contrast, the veto and NS activities of lymphokine-activated bone marrow cells are both abrogated by C lysis depletion of cells expressing Qa-2, Qa-5, Thy-1, asialo GM1, NK1, and Ly-11, but are unaffected by depletion of cells expressing Ly-2. Bone marrow cells depleted of Qa2+ cells fail to generate veto or natural suppressor activity when cultured in Con A-conditioned medium, unlike bone marrow cells depleted of mature NK1.1+ NK cells. Cloned NK cell line F8 is able to mediate both natural suppression and veto. These findings indicate that bone marrow veto and natural suppression are not mediated by T or NK cells present de novo in the bone marrow, but are dependent on proliferating cells that phenotypically resemble pre-NK cells. The progeny of these cells have the phenotype and functional activity of lymphokine-activated killer cells, and are capable of directly mediating both veto and natural suppression.

Animals↗

The non immunogenicity of CALLA in leukemic children.

The sera from 55 children with acute lymphoblastic leukemia (ALL) treated with active immunotherapy were examined for the presence of antibodies against common ALL antigen (CALLA). A solid phase indirect radioimmunometric assay (IRA) was developed which enabled the detection of anti-CALLA antibody in patients' sera, utilizing the ability of affinity-purified CALLA to bind Ricinus communis agglutinin and anti-CALLA antibody simultaneously. Using IRA, anti-CALLA antibody activity could not be detected in a majority of patients. We concluded that the patients did not raise comparable antibodies against CALLA, indicating this antigen is not immunogenic for ALL patients.

Antibodies, Neoplasm↗

Discontinuing chemoimmunotherapy in childhood acute lymphoblastic leukemia.

We examined the results of discontinuing therapy in Japanese children with acute lymphoblastic leukemia. Of the 209 patients in chemoimmunotherapy study, 120 (57.4%) had all chemotherapy stopped after 3 years of complete remission, and 72 (34.4%) reached the point of discontinuing immunotherapy after 5 years of complete remission. Of the 120 children removed from chemotherapy, 14 (11.7%) have relapsed, mainly in the extramedullary sites (5 testis, 5 bone marrow, 3 central nervous system, 1 bone); relapses occurred 1-23 months after cessation of chemotherapy (median 11 months). Boys had a higher post-chemotherapy relapse rate than girls (0.21 vs. 0.08, P less than 0.05). None of the 72 children removed from immunotherapy have yet relapsed. Long-term remission and possibly cure can be expected in approximately one half of newly-diagnosed Japanese patients. Moreover, the active immunotherapy could be of benefit to elimination of bone marrow relapses after cessation of chemotherapy in children with acute lymphoblastic leukemia.

Adolescent↗

Shedding of leukemia-associated P24 antigen by lymphoblastoid cell lines.

We report the development of a unique enzyme-linked immunosorbent assay (ELISA) which makes possible the detection of leukemia-associated P24 antigen, utilizing its ability to bind the Ricinus communis agglutinin (RCA1) and a monoclonal antibody, SJ-9A4 simultaneously. Using the RCA1/SJ-9A4-ELISA, P24 antigen, as few as 50 X 10(3) cells from a common acute lymphoblastic leukemia (C-ALL) cell line could be detected. The presence of D-galactose gave complete and specific inhibition of P24 antigen binding to RCA1. Matched concentrations of D-glucose and D-sucrose had no effect on binding. The release of the P24 antigen into the culture medium by a C-ALL cell line maintained at 37 degrees C could be detected; however, no P24 antigen was present in the culture medium when the cells were maintained at 4 degrees C. Sequential analysis of the culture medium for soluble P24 antigen revealed that release of the P24 antigen associated with cell growth. Molecular sieve chromatography of concentrated culture medium indicated that shed P24 antigen was eluted in the macromolecule fraction. P24 antigen was detected in the cerebrospinal fluid (CSF) of four patients with P24 positive ALL at the time of relapse of the central nervous system (CNS) and was undetectable while in complete remission. The CSF from three patients with P24 negative ALL and three patients with aseptic meningitis had no detectable activity.

Antibodies, Monoclonal↗

Immunological subclassification of non-T, non-B acute lymphoblastic leukaemia in childhood.

41 cases of non-T, non-B acute lymphoblastic leukaemia (ALL) were classified by immunological criteria using a panel of monoclonal antibodies against common ALL antigen (cALLa), p24, p20 and HLA-DR antigens. Out of 41 cases, cALLa, p24, p20 and HLA-DR antigens were positive in 31 cases, 34 cases, 35 cases and 41 cases, respectively. 4 cases expressing cytoplasmic mu heavy chains were included in the group of common ALL. We demonstrated that a majority of non-T, non-B ALL would be derived from B-lineage cells. The expression of p24 and p20 was followed by the expression of cALLa and the synthesis of cytoplasmic immunoglobulin. These items of evidence support the idea that the expression of cALLa, p24, p20 and HLA-DR antigens on ALL cells would be universal in the USA, Europe and Japan. Although morphologically identical, non-T, non-B ALL cases could be subdivided into phenotypically-defined subgroups on the basis of cALLa, p24, p20 and HLA-DR antigens.

Antibodies, Monoclonal↗

Cyclic nucleotide levels of nasal secretions in allergic patients and control subjects.

Cyclic nucleotides (CND) levels of nasal secretions were studied in allergic rhinitis patients and control subjects. In methacholine-induced nasal secretion, allergic rhinitis patients had lower cAMP levels, higher cGMP levels and a lower cAMP/cGMP ratio than the control subjects. A close relationship was found between CND levels and the severity of daily symptoms in both methacholine-induced and antigen-induced nasal secretions.

Cyclic AMP↗

Nasal responsiveness to methacholine stimulation in allergic rhinitis patients.

We examined the nasal responsiveness to topical methacholine application in allergic rhinitis and non-allergic chronic rhinitis patients, and in control subjects. Methacholine responsiveness was significantly higher in allergic rhinitis patients than in non-allergic patients and control subjects. In perennial rhinitis, methacholine responsiveness correlated with the severity of daily nasal symptoms and those provoked by specific allergen challenge tests. Among nasal symptoms, hyper-rhinorrhoea was found to be closely related to methacholine responsiveness. As a result of these findings, the possibility of cholinergic hyper-reactivity in allergic rhinitis patients is discussed.

Administration, Topical↗

[Experience with high-dose methotrexate therapy for malignant solid tumors].

Thirteen patients with malignant solid tumors, mainly osteogenic sarcomas, were treated by high-dose MTX therapy, 50-400 mg/kg, in a total of 72 cycles. It has been proved that this therapy was relatively safe provided careful clinical surveillance were assured. Of 8 patients with osteogenic sarcomas, 6 had no metastatic lesions on the chest X-rays before this therapy: three were alive without any evidence of disease for 18-25 months after high-dose MTX therapy. In some cases of other malignant solid tumors, particularly intracranial tumors, clinical efficacy was observed. Dose-time relationships, etc. should further be studied for more therapeutic efficacies of high-dose MTX therapy.

Adolescent↗

A child case of CD34+, CD33-, HLA-DR-, CD7+, CD56+ stem cell leukemia with thymic involvement.

It has been reported that the CD56+/CD7+/CD3- phenotype of natural killer (NK) cells develop from the CD34+/HLA-DR- bone marrow (BM) mononuclear cell population in long-term BM culture (LTBMC). An HLA-DR-/CD33+/CD56+/CD16- myeloid/natural killer cell acute leukemia has been described. We report here a 7-year-old boy who developed stem cell acute leukemia with superior vena cava syndrome secondary to thymic involvement. Surface marker analyses revealed that the leukemia cells showed CD34+/HLA-DR-/CD33-/CD7+/CD56+ phenotype. When stimulated with phorbol ester in vitro the leukemic cells morphologically differentiated to myeloid cells developing CD13, CD15 and CD56 antigens. Our results suggest that CD34+/HLA-DR-/CD7+/CD56+ stem cell leukemia may arise from transformation of a pluripotent precursor cell, which could differentiate to both myeloid and NK cell lineages.

Antigens, CD↗