[High-dose therapy and peripheral blood stem cell transplantation for patients with aggressive non-Hodgkin's lymphoma remaining in initial remission: results of a feasibility study].

High-dose therapy with peripheral blood stem cell transplantation (HDT/PBSCT) was performed as one aspect of front-line therapy in patients with poor-risk aggressive non-Hodgkin's lymphoma (high-intermediate/high risk) according to the age-adjusted international prognostic index (aaIPI). Twenty-nine patients were enrolled in this study between November 1994 and March 1999. CHOP + etoposide (CHOP-E) was used as an initial chemotherapy and as a chemotherapy agent for the purpose of cell harvesting. Peripheral blood stem cells were harvested from 17 patients, and HDT with CEC (carboplatin, etoposide, cyclophosphamide)/PBSCT was performed in 11 patients. Eighteen patients dropped out, including five for whom CHOP-E therapy was ineffective and 5 who did not give consent for cell harvesting or HDT/PBSCT. CHOP-E therapy produced complete remission (CR) in 15 out of 26 patients (58%) after discounting the 3 who were ineligible among the 29 who were initially enrolled. The median observation period after PBSCT in the 11 patients who underwent HDT/PBSCT was 25 months (3 to 50 months), and the 3-year disease-free survival rate was 73%. No serious complications associated with the transplantation were observed. We were able to confirm the feasibility and safety of HDT/PBSCT as one form of front-line therapy for aggressive non-Hodgkin's lymphoma in patients under 60 years of age.

[Intravascular lymphomatosis diagnosed by bone marrow biopsy].

Intravascular lymphomatosis (IVL) is a rare malignancy characterized by neoplastic proliferation of lymphoid cells within the lumina of small vessels. We report a case of IVL in a 69-year-old woman, who presented with pancytopenia and elevation of the serum LDH level. There was no skin eruption or neurological abnormalities. Clusters of abnormal lymphoid cells were barely evident in a peripheral blood smear. Laboratory examinations revealed high levels of LDH (2,602 IU/l) and sIL-2R (5,640 U/ml). Bone marrow aspiration revealed a normal cellular marrow with mild hemophagocytosis, but no tumor cells were detected. After admission, respiratory failure due to multiple pulmonary embolisms progressed, and continuous infusion of heparin had no apparent effect. Bone marrow vessels filled with lymphoma cells were observed in a biopsy specimen, thus establishing a diagnosis of IVL. Chemotherapy with the CHOP regimen was immediately instituted. The respiratory failure was dramatically improved, resulting in disappearance of the abnormal lymphoid cells from the bone marrow. After eight courses of CHOP, low-dose etoposide therapy was administered, and no symptoms of relapse were noticed. The diagnosis of IVL is difficult because it does not form masses of tumor cells. Bone marrow biopsy may be helpful for early diagnosis of IVL if the disease is suspected and searched for.

[Efficacy and safety of two methods of administration of granisetron injection for nausea and vomiting induced by chemotherapy for tumors in hematopoietic organs--a randomized crossover comparison between intravenous drip infusion and intravenous bolus injection].

We investigated the efficacy and safety of two methods of granisetron injection to treat nausea and vomiting induced by chemotherapy for tumors in hematopoietic organs. The methods of administration were intravenous drip infusion over 30 minutes, which is the conventional method, and intravenous bolus injection. In this study, 89.5% of patients in both groups (17/19 for each) were free from vomiting. No serious adverse events were observed in either administration group. Abnormal laboratory test values suspected to be related to granisetron were observed in 3 cases in the bolus injection group and in 2 cases in the drip infusion group. but did not pose any clinical problem. These results demonstrated the safety of both methods of administration. In conclusion, it is considered that granisetron intravenous bolus injection can be considered as the method of choice for the prevention of nausea and vomiting induced by chemotherapy for tumors in hematopoietic organs.

[Effective cyclosporine therapy to resistant-Evans syndrome].

Evans syndrome is a rare disease defined as autoimmune hemolytic anemia plus immune thrombocytopenia. We describe a 57-year-old man with Evans syndrome whose thrombocytopenia was refractory to conventional therapy, including prednisolone, danazol, azathiopurine, cyclophosphamide, vincristine, gamma-globulin and splenectomy. The patient was then treated with three cycles of pulsed high-dose dexamethasone (40 mg/day for 4 sequential days every 4 weeks) followed by cyclosporine A therapy (300 mg/day). The platelet counts dramatically increased from 2,000/microliter to 200,000/microliter. Although thrombocytopenia appeared again with the tapering of cyclosporine A, the platelet counts recovered by re-increase of cyclosporine A, and have remained above 100,000/microliter for more than 14 months. Treatment with cyclosporine A can provide an effective therapeutic choice for refractory Evans syndrome.

[Chronic active EB virus infection accompanied by monoclonal proliferation of granular lymphocytes].

An 18-year-old man was admitted to our hospital because of 39 degrees C fever for over one month, marked hepatosplenomegaly, and pancytopenia. Malignant histiocytosis, malignant lymphoma, or hemophagocytic syndrome were ruled out by bone marrow aspiration and liver biopsy. A diagnosis of chronic EB virus infection was made according to his characteristic clinical features, abnormally high titiers of anti-EBV antibodies (VCA-IgG x 2560, EA-IgG x 1280), and the detection of EBV genome in the peripheral blood mononuclear cells by polymerase chain reaction. He also manifested granular lymphocyte proliferative disorder (GLPD). The phenotype of the proliferating granular lymphocytes was CD2 (+), CD3 (-), CD56 (+), and IL-2R beta (+), showing the NK lineage of these cells. Chromosomal abnormality of the cells cultured for a short time with IL-2 and a monoclonal junctional DNA structure of EB virus terminal repeat analyzed by the Southern blotting provided definitive evidence for the monoclonal expansion of the granular lymphocytes. These findings indicate a causative role of EV virus in NK-GLPD or NK-leukemia.

Induction of cell surface interleukin 2 receptor alpha chain expression on non-T lymphoid leukemia cells.

We examined nine cases of adult non-T lymphoid leukemia to investigate the cell surface inducibility of interleukin 2 receptor alpha chain (IL-2R alpha) and beta chain (IL-2R beta) after in vitro culture with and without recombinant human interleukin-1 beta (rhIL-1 beta). Induction of IL-2R alpha was observed in four of six cases with precursor B-cell acute lymphoblastic leukemia (pre-B ALL) and in all of three cases with B-cell mature lymphoid neoplasm (two chronic lymphocytic leukemia and one leukemic phase of non-Hodgkin's lymphoma). All of the IL-2R alpha-inducible cases could express this spontaneously even without rhIL-1 beta, while IL-2R beta did not appear on leukemic cells from any of the cases tested. IL-2R alpha-inducible pre-B ALL cases displayed stem cell antigen CD34 and induced myeloid-associated antigen CD13 simultaneously. These results suggest that IL-2R alpha but not IL-2R beta is easily inducible in certain cases of mature B-cell lymphoid neoplasm and pre-B ALL with immature characteristics.

Humanized antibody directed to the IL-2 receptor beta-chain prolongs primate cardiac allograft survival.

IL-2Rs are expressed by T cells activated in response to foreign histocompatibility Ags but not by normal cells. This difference in IL-2R expression is exploited by blockade of IL-2Rs to achieve immunosuppression. High affinity IL-2Rs involve three subunits, IL-2R alpha, IL-2R beta, and IL-2R gamma. Murine Mik beta 1, a mAb that blocks IL-2 binding to IL-2R beta, was developed as an immunosuppressive agent. There was modest prolongation of cynomolgus cardiac allograft survival in animals treated with murine Mik beta 1 (mean survival 11.8 +/- 1.6 days compared with 8.2 +/- 0.4 days in untreated animals; p = 0.06). However, murine Mik beta 1 is ineffective in recruiting primate effector cells and is neutralized by monkey Abs directed toward the infused Ab. To circumvent these limitations, a humanized form of Mik beta 1, which is a largely human IgG1k Ab, except that murine hypervariable regions are retained, was developed. In vivo plasma survival of humanized Mik beta 1 was threefold longer than simultaneously administered murine Mik beta 1 (terminal t1/2, 104 +/- 10 h vs 37 +/- 2 h). Furthermore, humanized Mik beta 1 manifests Ab-dependent cellular cytotoxicity, an activity that is absent with the parental murine Mik beta 1. Graft survival was significantly prolonged by humanized Mik beta 1 treatment with survivals of 22, 22, 24, 27, 44, and > 300 days (p vs control < 0.01; p vs murine Mik beta 1 < 0.01). Survival was not prolonged further (p > 0.3) by the addition of humanized anti-Tac, which blocks interaction of IL-2 with IL-2R alpha subunits. There was no toxicity attributable to the use of Mik beta 1 Abs. Thus, humanized Mik beta 1 prolonged cardiac allograft survival in primates without toxicity and may be effective as an adjunct to standard immunosuppressive therapy.

[Cytokine and disease].

Cytokine is a generic term of biologically active molecules which are mainly produced by the immune-competent cells and regulate the immune response, inflammation and hematopoiesis. This includes interleukins (IL), colony-stimulating factors (CSF), interferons (IFN), tumor necrosis factors (TNF) and so on. These cytokines are glycoproteins with a molecular weight of 20,000-40,000 kD and work at very low concentrations of pM order. ILs and CSFs transduce their signal via specific cell-membrane receptors which usually consist of at least two subunits and belong to a newly identified superfamily of cytokine receptors. Characterization of cytokine/receptor system has had a considerable impact on many clinical fields including pathophysiology of diseases and therapy. For example, IL-4 and IL-5 has been revealed to play essential roles in IgE production in allergic diseases and eosinophilia in a hypereosinophilic syndrome, respectively. Receptor abnormality has also been proven to cause diseases; patients for X-linked severe combined immunodeficiency (X-SCID) have a specific defect in the gamma chain of the IL-2 receptor which is critical for thymic maturation of T cells. EPO, G-CSF, M-CSF, IFN, and IL-2 are already commercially available for therapeutic use. IL-1, IL-3, IL-6, and TNF may also be useful for mycosis fungoides, aplastic anemia, thrombocytopenia, and malignant melanoma, respectively. On the other hand, it is possible to modulate the immune response by using the monoclonal antibody directed to the cytokine receptor.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential expression of interleukin-2 receptors (alpha and beta chain) in mature lymphoid neoplasms.

We investigated the expression of interleukin-2 receptors (IL-2R) in 60 adult patients with mature lymphoid neoplasms by flow cytometric analysis, using two monoclonal antibodies, anti-Tac for IL-2R alpha-chain (IL-2R alpha) and Mik-beta 1 for IL-2R beta-chain (IL-2R beta). Among B-cell malignancies, IL-2R alpha was found in 13/25 (52%) cases of chronic lymphocytic leukemia (CLL) and its variants, 3/14 (21%) of a heterogeneous group of non-Hodgkin's lymphoma (NHL) and none of the plasma cell diseases. IL-2R beta was not observed in any of B-cell neoplasms. IL-2R alpha was more frequently expressed in CD11b(+) B-cell neoplasms than in CD11b(-) (P < 0.05). In T-cell disorders, all three cases of adult T-cell leukemia/lymphoma expressed IL-2R alpha but not IL-2R beta. IL-2R beta was detected in 3/8 cases of CLL and 2/3 of NHL and none of these cases expressed IL-2R alpha. CD8(+) malignant T-cells commonly displayed IL-2R beta. These data indicate that the IL-2R alpha and IL-2R beta in mature lymphoid neoplasms was expressed independently each other and was associated with the particular phenotypical characteristics of neoplastic cells, respectively.

Induction of interleukin-2 receptor alpha chain expression of immature acute myelocytic leukemia cells.

Leukemic cells from 27 adult patients with acute myelocytic leukemia (AML) were investigated to determine the cell surface inducibility of interleukin-2 receptor (IL-2R) in in vitro culture with and without interleukin-1 beta (IL-1 beta). IL-2R alpha chain (IL-2R alpha) was induced on leukemic cells in 11 of 27 cases. Most of the cases could induce IL-2R alpha spontaneously without IL-1 beta, while the IL-2R beta chain (IL-2R beta) did not appear on leukemic cells from any of the cases tested. AML cases expressing CD7 or HLA-DR antigen could induce IL-2R alpha more frequently than any other type of AML. Among interleukin-3 (IL-3), granulocyte-macrophage colony stimulating factor (GM-CSF) and G-CSF, IL-3 showed a more prominent effect on DNA synthesis in IL-2R alpha inducible cases than in its uninducible cases. These results suggest that IL-2R alpha but not IL-2R beta was easily inducible on AML cells with immature characteristics.

Cooperative interactions between the interleukin 2 receptor alpha and beta chains alter the interleukin 2-binding affinity of the receptor subunits.

The interleukin 2 (IL-2) receptor (IL-2R) is a multisubunit receptor that includes three major IL-2 binding subunits, the IL-2R alpha, beta, and gamma chains. We have detected and analyzed cooperative interactions between the IL-2R alpha and beta chains (IL-2R alpha and IL-2R beta, respectively) in COS cells transfected with cDNAs encoding the IL-2R alpha, the IL-2R beta, or both cDNAs. We demonstrated that IL-2 F42A, an analog that fails to bind to the isolated IL-2R alpha subunit and would be predicted by the hierarchical affinity-conversion model to have impaired binding to cells expressing both chains, instead readily binds to the IL-2R alpha/beta heterodimer in COS cells. Furthermore, this binding is abolished by the antibody HIEI that separates the two IL-2R subunits. The monoclonal antibodies anti-Tac and Mik-beta 1 directed at the IL-2-binding sites on IL-2R alpha and IL-2R beta, respectively, block ligand binding to the heterodimer. This binding pattern is inconsistent with the strict hierarchical affinity-conversion model that mandates an initial binding of IL-2 to IL-2R alpha followed by binding of the IL-2/IL-2R alpha complex to IL-2R beta. Instead, our results support an alternative model of preformed complexes of IL-2R beta with other IL-2R subunits. In this alternative model, IL-2R alpha and -beta exist in part as preformed complexes in which the affinity of IL-2R beta for IL-2 is altered by the proximity of IL-2R alpha, through mechanisms that do not require the prior binding of IL-2 to IL-2R alpha.

Generation of monoclonal antibodies to the rabbit interleukin-2 receptor alpha chain (CD25) and its distribution in HTLV-1-transformed rabbit T cells.

Rabbits can be infected with human retroviruses such as human T-cell leukemia virus-1 (HTLV-1) and human immunodeficiency virus (HIV), and provide useful animal models to study retroviral diseases such as adult T-cell leukemia and HIV. Previously we have succeeded in generating monoclonal antibodies (mAbs) against rabbit CD4, CD5 and CD11a antigens. To make this animal species more amenable to cellular and molecular studies, we have attempted to extend the panel of mAbs against rabbit CD antigens. Here we report on the generation of three neutralizing mAbs against interleukin-2 receptor alpha chain (IL-2R alpha) (CD25), Kei-alpha 1 (IgG2b), Kei-alpha 2 (IgG2a) and Kei-alpha 3 (IgG1). They specifically recognize the rabbit Mr 55,000 IL-2 binding protein, IL-2R alpha, and completely inhibit both high- and low-affinity IL-2 binding to F648b cells that express IL-2R alpha as well as IL-2R beta. The use of mAb Kei-alpha 1 confirmed that the rabbit IL-2R alpha is not only a low-affinity IL-2R on its own but also an essential component of high-affinity IL-2R as found in other animal species, and that rabbit activated T cells including HTLV-1-transformed cell lines express high levels of the IL-2R alpha. Together with mAbs against various rabbit CD antigens that we reported previously, these neutralizing mAbs to IL-2R alpha will be valuable for studies of human retrovirus infections, such as those induced by HTLV-1 or HIV, in rabbits.

Humanized Mik beta 1, a humanized antibody to the IL-2 receptor beta-chain that acts synergistically with humanized anti-TAC.

Mik beta 1 is a mouse mAb directed at the beta-subunit of the human IL-2R (Tac) that inhibits IL-2 binding and inhibits IL-2 induction of large granular lymphocytes (LGL). Mik beta 1 alone does not inhibit IL-2-induced T-cell proliferation, but acts synergistically with anti-Tac to inhibit IL-2-induced proliferation of activated T cells. To evaluate these effects for possible therapy in humans, we constructed two humanized Mik beta 1 antibodies by combining the complementarity-determining regions of the murine antibody with human framework and constant regions. Compared with murine Mik beta 1, the two humanized Mik beta 1 antibodies, which differ in their degree of humanization, had similar affinities for IL-2R beta. The murine Mik beta 1 and one of the humanized Mik beta 1 antibodies were equivalent in competing for IL-2 binding to IL-2R beta and inhibiting IL-2 induction of LGL cytotoxicity. The activity of the second humanized antibody was significantly reduced. The three Mik beta 1 antibodies act synergistically to varying degrees with humanized anti-Tac to prevent IL-2-induced proliferation of activated T cells. This capacity to synergize paralleled their abilities to inhibit IL-2 binding. In addition, both humanized antibodies directed antibody-dependent cell-mediated cytotoxicity. We hope that humanized Mik beta 1 in combination with humanized anti-Tac will provide a new immunosuppressive therapy for the treatment of autoimmune diseases, graft-versus-host disease, and prevention of allograft rejection.

Pseudo-high affinity interleukin 2 (IL-2) receptor lacks the third component that is essential for functional IL-2 binding and signaling.

Functional studies of the interleukin 2 receptor (IL-2R) of two (ED515-D and Kit225) IL-2-dependent and three (ED515-I, 3T3-alpha beta 11, and Hut102) IL-2-independent cell lines were done. All of these cell lines appeared to express high as well as low affinity IL-2R. However, ED515-I and 3T3-alpha beta 11, which expressed the IL-2R beta chain, did not bind IL-2 at all when IL-2 binding to their IL-2R alpha chain was blocked with anti-Tac monoclonal antibody, whereas the intermediate affinity binding in ED515-D, Kit225, and Hut102 cells remained. We tentatively called the high affinity IL-2R of the former cells pseudo-high affinity IL-2R. The dissociation constant of pseudo-high affinity IL-2R was higher than that of ordinary high affinity IL-2R. Internalization of cell-bound 125I-IL-2 into ED515-I and 3T3-alpha beta 11 cells was less efficient than that into ED515-D cells. The addition of IL-2 neither promoted cell growth nor upregulated IL-2R alpha chain expression in ED515-I and 3T3-alpha beta 11 cells. Furthermore, tyrosine phosphorylation of the cellular proteins (p120, p98, p96, p54, and p38) was induced or enhanced in response to the addition of IL-2 in ED515-D and Kit225 cells, but not in the cell lines expressing pseudo-high affinity IL-2R. Finally, 125I-IL-2 crosslinking followed by SDS-PAGE analysis showed an 80-kD band corresponding to p65 + IL-2, in addition to bands corresponding to IL-2R alpha and beta chain + IL-2 in cells bearing ordinary high affinity IL-2R but not in cells with pseudo-high affinity IL-2R. Taken together, we consider that another protein whose molecular mass is approximately 65 kD is functionally important in IL-2 binding and subsequent signal transduction and may be the third component of IL-2R.

Mik-beta 1(Fv)-PE40, a recombinant immunotoxin cytotoxic toward cells bearing the beta-chain of the IL-2 receptor.

Mik-beta 1 is a mAb that binds to the beta subunit of the IL-2R. We have constructed a recombinant single chain immunotoxin Mik-beta 1(Fv)-PE40 by genetically fusing the H and L V domains of Mik-beta 1 to each other via a peptide linker, and then to PE40, a derivative of Pseudomonas exotoxin. Mik-beta 1(Fv)-PE40 was selectively cytotoxic for cells expressing high levels of IL-2R beta (p75) subunit. Mik-beta 1(Fv)-PE40 was cytotoxic to the NK cell line YT-S, which expresses p75 but not p55 subunits, with an IC50 of 6 ng/ml. The ATL line HUT-102 was less sensitive, with an IC50 of 200 ng/ml. However, the IC50 could be lowered to 11 ng/ml when Mik-beta 1(Fv)-PE40 was allowed to bind to HUT-102 cells at 4 degrees C for 4 h before overnight incubation at 37 degrees C. An excess of Mik-beta 1 but not of anti-Tac, the anti-p55 mAb, prevented the cytotoxicity of Mik-beta 1(Fv)-PE40. We constructed a more active version of Mik-beta 1(Fv)-PE40, designated Mik-beta 1(Fv)-PE40KDEL, by converting the carboxyl-terminus of the toxin from -REDLK to -KDEL. Mik-beta 1(Fv)-PE40KDEL showed an IC50 of 2 ng/ml toward YT-S cells and 35 ng/ml toward HUT-102 cells. Binding studies using radioiodinated Mik-beta 1 showed that Mik-beta 1(Fv)-PE40 bound to the p75 receptor subunit with 11% of the affinity of the native Mik-beta 1 antibody. Mik-beta 1(Fv)-PE40 may be a useful reagent to study cells that express IL-2R, and it deserves further study as a possible treatment for cancers in which the malignant cells express high numbers of p75 subunit.

Interleukin-2 (IL-2) induces erythroid differentiation and tyrosine phosphorylation in ELM-I-1 cells transfected with a human IL-2 receptor beta chain cDNA.

The molecular mechanism of erythroid differentiation has been still ill-defined. In this study, we introduced a human interleukin-2 receptor (IL-2R) beta chain cDNA into ELM-I-1 cells which differentiated into hemoglobin-positive cells in the presence of erythropoietin (Epo), and established the transformant which expressed IL-2R beta chain. In this transformant, we revealed that IL-2 induced erythroid differentiation and the same pattern of tyrosine phosphorylation as Epo. These data suggest that tyrosine phosphorylation is involved in signal transduction pathway of erythroid differentiation. It is also implicated that the Epo and IL-2 receptor system share a common signal transduction pathway.

Interleukin-2 (IL-2) induces tyrosine kinase-dependent translocation of active raf-1 from the IL-2 receptor into the cytosol.

Stimulation of the interleukin-2 (IL-2) receptor results in phosphorylation and activation of cytosolic Raf-1 serine/threonine kinase. Herein, we report that enzymatically active Raf-1 is physically associated with the IL-2 receptor beta chain (p75) in T-cell blasts. Following stimulation with IL-2, Raf-1 dissociates from the IL-2 receptor complex and translocates to the cytosol. Genistein, a protein tyrosine kinase inhibitor, prevents the dissociation of enzymatically active Raf-1 from the ligand-stimulated IL-2 receptor complex. These data favor a model of IL-2 receptor activation in which an IL-2-activated protein tyrosine kinase phosphorylates the IL-2 receptor and/or receptor-bound Raf-1. Following tyrosine phosphorylation, enzymatically active Raf-1 dissociates from the IL-2 receptor and translocates into the cytosol.