Résumé
Recombinant human Interleukin-2 (rhIL-2) continues to be in therapeutic application for the treatment of melanoma and renal cell carcinoma. A regimen of several, repeated dose, daily intravenous injections for 14 or 28 days duration has been shown to induce mortality prior to scheduled terminal sacrifice of the animals. The conventional study design not only manifests in pre-terminal mortalities but also minimizes the characterization of toxic profile of the molecule. In humans, each intravenous treatment exposure involves two five-day treatment cycles separated by 9 days of rest period. The current 28-day study has been designed with three cycles of treatment and two rest periods, each treatment period comprising 5 days of consecutive treatment with 6 or 7 days of rest period. The study included three dose levels at 10, 20 and 40 times the human dose. Treatment related clinical signs such as reduction in the spontaneous activity of animals, abdominal breathing and scruffy coat were noticed in a few animals treated at mid- or high-dose levels. Treatment induced adverse changes were apparent in platelet counts and plasma activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyl transferase (GGT) at mid- or high-dose levels. Histopathology revealed inflammatory cell infiltrates and/or its associated degenerative/regenerative changes in lung, liver and kidneys. The pharmacodynamic response, increase in white pulp was observed in the spleen, which was also evident in the total leukocyte count (WBC count) with a primary increase in the counts of lymphocytes and eosinophils. At the lowest dose level, which was 10 times the human dose, there were no manifestations of major adverse toxicity.
Résumé
Objectivc To observe the therapeutic effects of combined cytokines on hematopoietic injuries induced by 4.5 Gy60 Co γ-rays irradiation in beagles,and to provide experimental evidences for the clinical treatment of extremely severe myeloid acute radiation sickness(ARS).Methods 16 beagles were given 4.5 Gy60 Co γ-rays total body irradiation,and then randomly assigned into irradiation control group,supportive care group and cytokines group.In addition to supportive care,recombinant human granulocyte colony-stimulating factor (rhG-CSF),recombinant human interleukin-11(rhIL-11)and recombinant human interleukin-2(rhIL-2)were administered subcutaneouly to dogs in cytokines group.Peripheral blood hemogram was examined once every two days.Bone marrow and peripheral blood were collected to proceed colony cultivation 4 d pre-irradiation and 1 and 45 d post-irradiation.Conventional histopathological sections of sternum were prepared to observe the histomorphology changes. Results After irradiation,the population of all kinds of cells in peripheral blood declined sharply.WBC nadir Was elevated(1.04×109/L,but 0.28×109/L and 0.68×109/L for the irradiation control group and the supportive care group separately),the duration of thrombocytopenia was shortened (24 days,but 33 days for the supportive care groug) and red blood cell counts were maintained in the range of normal values after cytokincs treatment in combination.The colony forming efficiency of haemopoietic stem cells(HSCs)in bone marrow and peripheral blood decreased obviously 1 d post irradiation,but recovered to the level of that before irradiation 45 d post irradiation after supportive care and cytokines treatment.Hematopoietic cells disappeared in bone marrow of animals in irradiation control group,but hematopoietic functions were recovered after cytokines were administrated.Conclusions RhG-CSF.rhIL-11 and rhIL-2 used in combination could elevate WBC nadir,accelerate the recovery of leukocytes,platelets and red blood cells and promote the proliferation,differentiation and maturity of HSPCs left in the body after 4.5 Gy γ-rays total body irradiation,eventually restore the hematopoietic function.Hence,combination of rhG-CSF,rhIL-11 and rhIL-2 could serve as better therapeutic strategy to treat extremely severe myeloid ARS.
Résumé
For purifying recombinant human IL—2 (rhIL—2),the columns of immunoabsorptionwere prepared with 4 anti—IL—2 McAb (9B12,9F5,9B2 and 8H7) purified by caprylic acid.Although 4 McAbs differ as regards their antigen—antibody binding characteristics,all they canserve as effective immnoabsorbents,provided optimum condition was adopted.The recoveryrate of 9B12,9F5,8H7 and 9B2 columns were 49.2%,37.5%,31.5% and 18.8% respec-tively.The purity of rhIL—2 obtained was more than 95% and biological activity remainedhigher.
Résumé
Objective To induce human mononuclear cell of cord blood into CD 3 activating killing (CD 3AK) cells with anti-CD 3 monoclonal antibody (CD 3McAb) and recombinant human interleukin-2 (rhIL-2), so that their proliferative activity, activity of killing action, phenotypes and level of secretory cytokines can be observed dynamically. Methods The increase of the number of cells was counted by Tapan-blue staining. The killing action can be measured by using methyl -thiazolyl-tetrazolium-array. The phenotypes of cells were analysed by using indirect immunofluorescence assay. The levels of IL-6, interferon-? (IFN-?) and tumor necrotic factor-? (TNF-?)in culture supernatants were analysed by using enzyme-linked irnmunosorbent assay(ELISA). Results The increase of the number of CD 3AK cells from cord blood was the highest amounting to 78.56 times in the second week. The killing action reached the peak on day 12, and all target cells (malignant cell lines) could be killed significantly. The heterogeneous phenotypes of CD 3AK cells showed that the number of cells with CD 3+, CD 8+, CD 25+, CD 38+, CD 16+ and CD 56+ increased significantly on day 7,14 compared with those of pre-culture (P