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Biomedical subjects

O Tanabe

Publications and source records attributed to O Tanabe.

51 records · Page 3Linked to original sources
PubMed1989

[A case of refractory multiple myeloma demonstrating a relationship between the progression of the disease and in vitro myeloma cells activity].

In vitro proliferation (3H-TdR-uptake) and M-protein secretion rate by highly purified myeloma cells from bone marrow aspirates were examined serially to evaluate the progression of multiple myeloma in a patient who was refractory to conventional alkylating agents. Following the administration of IFN-alpha, serum M-protein decreased significantly, with the reduced in vitro spontaneous M-protein secretion rate from the separated myeloma cells. Similarly, when IFN-alpha as low as 10 u/ml was added in vitro, it also suppressed M-protein secretion from myeloma cells of this patient, suggesting that, the observed decrease of serum M-protein was due to diminished M-protein secretion by the myeloma cells themselves, as well as the reduction of the tumor cell burden. On the other hand the in vitro 3H-TdR uptake by the myeloma cells increased markedly with the decrease in the M-protein secretion rate. Five months after the initiation of IFN-alpha treatment, tumor formation at the lumbar vertebrae occurred when serum M-protein level was still low, followed by a bone marrow relapse. These results suggest that serial assessments of proliferation and M-protein secretion potential of myeloma cells in vitro can be helpful in predicting the progression of multiple myeloma.

Cell Division↗
PubMed1989

Interleukin-1 accelerates autocrine growth of myeloma cells through interleukin-6 in human myeloma.

Recombinant interleukin 1 alpha (rIL-1 alpha) augmented proliferation of freshly isolated myeloma cells as well as B-cell stimulatory factor 2 (BSF-2)/interleukin-6 (IL-6). Recombinant IL-1 alpha-induced proliferation was partially inhibited by anti-IL-6 antibody. In the culture supernatants of rIL-1 alpha-stimulated myeloma cells, IL-6 activities, which were measured by using an IL-6-dependent murine hybridoma clone, MH60.BSF2, were increased, when compared with those in the culture supernatants of nonstimulated myeloma cells. Furthermore, IL-6 messenger RNA (mRNA) expression was also augmented in IL-1 alpha-stimulated myeloma cells. Therefore rIL-1 alpha stimulates myeloma cells to produce IL-6, which consequently augments proliferation of myeloma cells. Thus, IL-1 can accelerate autocrine growth of myeloma cells through IL-6.

Adjuvants, Immunologic↗
PubMed1989

Sensitive inhibitory effect of interferon-alpha on M-protein secretion of human myeloma cells.

The effects of interferon-alpha (IFN alpha) on in vitro proliferation and M-protein secretion in human myeloma cells were investigated. Human myeloma cells were purified from bone marrow aspirates in 12 multiple myeloma patients. Purified myeloma cells were cultured for 48 hours with IFN alpha at its lower concentrations (0.1 to 100 U/mL). The cells were then pulsed with 3H-TdR for the last 12 hours and 3H-TdR uptake was measured (in vitro proliferation). After 48-hour culture, supernatants were harvested and the amount of M-protein in these fluids were measured by enzyme-linked immunosorbent assay (ELISA) (in vitro M-protein secretion). In vitro M-protein secretions of myeloma cells were significantly suppressed even at 0.1 U/mL of IFN alpha, while 3H-TdR uptakes were not so suppressed until 10 or 100 U/mL of IFN alpha were added. The expressions of secretory immunoglobulin (Ig) mRNA of these myeloma cells were also selectively suppressed by IFN alpha. Furthermore, after IFN alpha had been administered intramuscularly, 3 to 6 x 10(6) U/d for at least 1 month, in vitro M-protein secretions of these myeloma cells were decreased compared with those before IFN alpha administration. Therefore, these results suggest that IFN alpha has more sensitive inhibitory effect on M-protein secretion of human myeloma cells rather than on myeloma cell proliferation.

Blood Proteins↗
PubMed1988

Genomic structure of the murine IL-6 gene. High degree conservation of potential regulatory sequences between mouse and human.

The genomic clone of mouse IL-6 was isolated and compared with the human IL-6 gene. The comparison revealed that the mouse IL-6 consists of five exons and four introns and that the overall organization is similar to that of the human IL-6 gene although the third intron is about 2 kb longer. The sequence similarity in the coding region is about 60%, whereas the 3'-untranslated region and the first 300-bp sequence of the 5'-flanking region are highly conserved (greater than 80%). Several sequence blocks with high homology are also found in the introns. Furthermore, sequences similar to transcriptional enhancer elements such as the c-fos serum responsive element and the consensus sequences for cAMP induction, activator protein 1 binding, and the glucocorticoid receptor binding are identified within the highly conserved 5'-flanking regions of the genes from the two species. These sequences may play an important role in transcriptional activation of the IL-6 gene.

Amino Acid Sequence↗
PubMed1988

Autocrine generation and requirement of BSF-2/IL-6 for human multiple myelomas.

Human B cell stimulatory factor 2 (BSF-2) was originally characterized and isolated as a T cell-derived factor that caused the terminal maturation of activated B cells to immunoglobulin-producing cells. Molecular cloning of the complementary DNA predicts that BSF-2 is a protein of relative molecular mass (Mr) 26,000 similar or identical to interferon beta 2, hybridoma plasmacytoma growth factor and hepatocyte stimulating factor. IL-6 has been proposed as a name for this molecule. It is now known that BSF-2 has a wide variety of biological functions and that its target cells are not restricted to normal B cells. Responses are also seen in T cells, plasmacytomas, hepatocytes, haematopoietic stem cells, fibroblasts and rat phoeochromocytoma, PC12 (Satoh, T. et al., manuscript in preparation). Of particular interest to this report is that human BSF-2 is a potent growth factor for murine plasmacytomas and hybridomas. This observation suggested to us that constitutive expression of BSF-2 or its receptor could be responsible for the generation of human myelomas. In this study we report that myeloma cells freshly isolated from patients produce BSF-2 and express its receptors. Moreover, anti-BSF-2 antibody inhibits the in vitro growth of myeloma cells. This is direct evidence that an autocrine loop is operating in oncogenesis of human myelomas.

Antibodies↗
PubMed1988

Decrease in BSF-2/IL-6 response in advanced cases of multiple myeloma.

Human myeloma cells freshly isolated from 40 patients with IgG multiple myeloma (MM, 10 in stage I and 30 in stage III), were cultured for 48 hours with recombinant B cell stimulatory factor 2 (rBSF-2)/interleukin-6 (IL-6), which is considered a major growth factor for myeloma cells. Uptake of 3H-thymidine by these purified myeloma cells was measured, and BSF-2 response was evaluated by stimulation index and delta cpm induced by rBSF-2. Myeloma cells from cases in stage I responded to rBSF-2 better than those in stage III. Moreover rBSF-2 responders also showed better response to chemotherapy. Therefore, these results suggest that in vitro response of myeloma cells to BSF-2 correlates with disease progression and clinical response in patients of MM.

Humans↗
PubMed1988

Separation of human myeloma cells from bone marrow aspirates in multiple myeloma and their proliferation and M-protein secretion in vitro.

Human myeloma cells were purified from bone marrow aspirates from patients with multiple myeloma (MM) by Percoll discontinuous density-gradient centrifugation, E rosette formation and treatment with antimyelomonocytic antibody (Leu M1), plus complement. Thus, the purified cell fraction consisted of greater than 90% myeloma cells, even when as little as 15% myeloma cells were contained in bone marrow mononuclear cell fraction, determined by morphological and immunologic examinations. With highly purified myeloma cells from 29 patients with IgG type MM, biologic characteristics such as spontaneous proliferation (3H-TdR uptake) and M-protein secretion rate in vitro were evaluated. Both activities varied among patients within stage I and III, and a 3H-TdR uptake of 255-24, 132 cpm/4 x 10(4) cells, and an M-protein secretion rate of 9 to 72 pg/cell/day, respectively, were recorded. However, in each patient, there was no correlation between 3H-TdR uptake and M-protein secretion rate. These results thus suggest that 3H-TdR uptake and M-protein secretion rate of highly purified myeloma cells are independent biologic parameters, not associated with the clinical stages, and the purification of myeloma cells we describe can contribute to further studies on the biologic characteristics and to understanding of the pathophysiology involved in MM.

Blood Proteins↗
PubMed1975

Action of crystalline acid carboxypeptidase from Penicillium janthinellum.

Acid carboxypeptidase (EC 3.4.12.-) crystallized from culture filtrate of Penicillium janthinellum has been investigated for its use in carboxy-terminal sequence determination of Z-Gly-Pro-Leu-Gly, Z-Gly-Pro-Leu-Gly-Pro, angiotensin I, native lysozyme, native ribonuclease T1, and reduced S-carboxy-methyl-lysozyme. The examination indicated that proline and glycine were liberated from Z-Gly-Pro-Leu-Gly-Pro. At high enzyme concentration, the enzyme catalyzed complete sequential release of amino acids from the carboxy-terminal leucine to the amino-terminal aspartic acid of angiotensin I. The enzyme released the carboxy-terminal leucine from native lysozyme, however, no release of the threonine from native ribonuclease T1 was observed after a prolonged period of incubation with the enzyme. The sequence of the first nine carboxy-terminal residues of denatured lysozyme, leucine, arginine, S-carboxymethyl-cysteine, glycine, arginine, isoleucine, tryptophane, alanine, and glutamine, could be deduced unequivocally from a time release plot of an incubation mixture with the enzyme.

Amino Acid Sequence↗
PubMed1974

Production and some properties of a new type of acid carboxypeptidase of Penicillium molds.

Among some 38 strains of the genus Penicillium we investigated seven wild-type strains (P. daleae IFO-6087, P. frequentans AHU-8328, P. funiculosum IAM-7013, P. janthinellum IFO-8070, IAM-7026, P. lividum IAM-7200, and P. oxalicum AHU-8336) that were found to be excellent strains for a new type of acid carboxypeptidase production in a surface koji culture at 25 C. The production of acid carboxypeptidase was determined in various culture conditions in a koji culture. The maximum yields of acid carboxypeptidase were obtained by P. janthinellum IFO-8070. Partial purification and isolation of the acid carboxypeptidase from strains of Penicillium were performed with gel filtration on Bio-Gel P-100. Characterization studies indicate that the acid carboxypeptidases from P. daleae IFO-6087, P. funiculosum IAM-7013, P. janthinellum IFO-8070, and P. oxalicum AHU-8336 have some properties similar to those of the enzyme of Aspergillus saitoi with regard to the hydrolysis of several peptides at acidic pH range but have other slightly different properties with regard to stability, pH optima, inhibitors, and molecular weights.

Carboxypeptidases↗
PubMed1974

Submerged production, purification, and crystallization of acid carboxypeptidase from Penicillium janthinellum IFO-8070.

Penicillium janthinellum IFO-8070 produced an acid carboxypeptidase of molecular weight 51,000 in a liquid medium at 25 C. Maximum enzyme concentration was obtained within 3 to 6 days in a medium containing 2% wheat bran, 1% defatted soybean, and 1% KH(2)PO(4); the initial pH was 2 to 4. When submerged aerobic conditions were used, a 51,000-molecular-weight acid carboxypeptidase was produced and no detectable amounts of 160,000-molecular-weight acid carboxypeptidase were produced. Acid carboxypeptidase with a molecular weight of 51,000 was purified 330-fold from koji culture to yield a crystalline protein which was demonstrated by disc electrophoresis to be homogeneous. The purification method included ammonium sulfate fractionation, Amberlite CG-50 chromatography, acetone fractionation, Amberlite CG-50 rechromatography, and concentration in a collodion bag. The specific activity of the enzyme was about three times more than that of the acid carboxypeptidase from Aspergillus saitoi.

Acetone↗