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Biomedical subjects

K Nilsson

Publications and source records attributed to K Nilsson.

At least 271 records · Page 15Linked to original sources

Specific binding of B-CLL cell-derived chemokinetic inhibitory factor (CIF) to human polymorphonuclear leukocytes.

The chemokinetic inhibitory factor (CIF) is a recently described B-cell derived lymphokine that mediates a chemokinetic inhibitory effect on human polymorphonuclear leukocyte (PMN) migration. In the present report the interaction of CIF with the neutrophil plasma membrane was studied. Normal human peripheral blood neutrophils and purified neutrophil plasma membranes selectively removed biologic activity from CIF-containing concentrates obtained during the purification procedure from conditioned medium. Removal was obtained at both 4 degrees C and 37 degrees C. Furthermore, HL-60 cells treated with dimethyl sulfoxide removed CIF activity (granulocyte-like cells) but HL-60 cells treated with 12-O-tetradecanoylphorbol-13-acetate (macrophage-like cells) did not. Purified human blood monocytes, cells from the macrophage-like U-937 cell line and cells from the basophilic leukemia cell line KU-812 did not remove CIF. These studies suggest that neutrophils express specific binding sites for CIF-activity.

Binding Sites↗

Variation in iron accumulation, transferrin membrane binding and DNA synthesis in the K-562 and U-937 cell lines induced by chelators and their iron complexes.

Eight chelators - 8-hydroxyquinoline, 1-hydroxypyridine-2-thione (omadine), tropolone, pyridoxal isonicotinoyl hydrazone, 2-methyl-3-hydroxypyr-4-one (maltol), 1-methyl-3-hydroxypyrid-2-one, 1,2-dimethyl-3-hydroxypyrid-4-one and mimosine--and their iron complexes were tested on cells of the established human tumour cell lines K-562 (erythroleukaemic) and U-937 (monoblastoid) for their effects on a) cellular accumulation of iron provided by transferrin (Tf) via receptor-mediated endocytosis, b) specific cell surface binding of Tf, c) cell viability and, d) DNA synthesis. The lipophilic chelators suppressed the accumulation of Tf-supplied iron in the K-562 cells and less so in the U-937 cells, whereas the effects of the other chelators were closer to control range. The lipophilic chelators pyridoxal isonicotinoyl hydrazone, tropolone, 8-hydroxyquinoline and omadine were found to be cytotoxic in this order, with the U-937 being generally more sensitive than K-562. The presence of iron diminished the toxicity. The DNA synthesis was also affected, from a partial suppression in K-562 to a slight increase in U-937 in the presence of pyridoxal isonicotinoyl hydrazone and to strong suppression with 8-hydroxyquinoline and omadine. Addition of iron partially reversed the inhibition. The other chelators had low cytotoxic effects that disappeared upon iron saturation. Maltol, particularly in the absence of iron, 1,2-dimethyl-3-hydroxypyrid-4-one and 1-methyl-3-hydroxypyrid-2-one supported DNA synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

DNA↗

Tolerance of radiotherapy combined with adjuvant chemotherapy in breast cancer.

Forty-three postmenopausal breast cancer patients with axillary lymph node metastasis were randomized to receive postoperative radiotherapy (45 Gy) or the combination of radiotherapy and 6 months of chemotherapy. Forty-three premenopausal patients had postoperative radiotherapy and were randomized to receive one of two different chemotherapy combinations. Pulmonary fibrosis was roentgenologically registered in approximately 70 per cent of the total patient population six months after initiation of therapy. Addition of chemotherapy with doxorubicin and cyclophosphamide significantly increased the proportion of patients with pulmonary fibrosis compared with patients treated with radiotherapy only or radiotherapy combined with cyclophosphamide, methotrexate and 5-fluorouracil. Premenopausal patients tolerated the combination of radiotherapy and chemotherapy better than postmenopausal patients of whom approximately 30 per cent did not tolerate 65 per cent or more of prescribed total dose of chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

TPA-induced differentiation of chronic lymphocytic leukemia cells: studies on mu-chain expression.

The regulation of IgM synthesis and secretion was studied in chronic lymphocytic leukemia cells, with a phenotype roughly similar to peripheral resting B cells, during phorbol ester (12-O-tetradecanoylphorbol-13-acetate)-induced differentiation. TPA treatment caused a 20 times increase in total RNA synthesis and 20 to 50 times increase in the protein synthesis as compared to control cells. Morphologically, 70-90% of the cells reached the lympho- or plasmablast stage of differentiation. In control culture cells, approximately equal amounts of mRNA coding for secretory (s) and membrane (m) mu-chains were found. The micron message was translated as surface IgM expression was detected. A posttranscriptional regulation of microsecond synthesis appears to exist, since only low amounts of cytoplasmic mu-chains were detected by immunoprecipitation and SDS-PAGE, and no secretion of pentameric IgM was detected as measured by an RIA. TPA induction caused a relative increase in the microseconds to microns mRNA ratio, demonstrating differentiation associated control mechanisms operating at the level of mRNA processing. The high levels of cytoplasmic microsecond-chain precursor and the efficient secretion of pentameric IgM in TPA-induced chronic lymphocytic leukemia cells indicated the presence also of posttranscriptional controls.

Aged↗

Effects of recombinant interferon-alpha and -gamma on B-CLL cells in serum-free medium: expression of activation, differentiation, and CALLA antigens.

Chronic B-lymphocytic leukemia (B-CLL) cells from 10 patients were cultured serum-free with recombinant interferon (rIFN)-alpha 2, rIFN-gamma, or phorbol ester (TPA) for 5 days. All three agents induced functional differentiation, as evidenced by IgM secretion, without concomitant proliferation. A panel of monoclonal antibodies was used to detect changes in cell surface antigens defining pre-B cells (CALLA), resting B cells (HH1), early (4F2, MHM6) and late (anti-Tac, OKT9) B cell activation, and terminally differentiated B cells (OKT10). The activation markers 4F2, MHM6, and anti-Tac and the plasma cell marker T10 were all significantly induced with TPA, rIFN-alpha 2, an rIFN-gamma, whereas the expression of HH1 decreased. CALLA was detected on substantial proportions of differentiated (4-38%) but not resting (0-4%) B-CLL cells. The CALLA-positive B-CLL cells were negative for nuclear terminal deoxynucleotidyl transferase (TdT). The T9 antigen was expressed on TPA-treated cells (1-16%) only. The present findings indicate novel properties of IFN-alpha and IFN-gamma in inducing terminal differentiation of human monoclonal B cells without prior activation.

Antigens, Surface↗

Establishment and phenotypic characterization of three new human myeloma cell lines (U-1957, U-1958, and U-1996).

Three new human myeloma cell lines (U-1957, U-1958, and U-1996) have been established in vitro. The cell lines are Epstein-Barr virus (EBV) negative, monoclonal, and aneuploid and should thus represent malignant cell populations and not EBV-carrying non-neoplastic B lymphoblastoid cell lines. The myeloma origin of the cell lines is also suggested by their capacity for production of monoclonal complete immunoglobulin (Ig) molecules (U-1957 and U-1958) or IgG light chains (U-1996) of the same type as the myeloma protein in vivo. All the cell lines have morphological features of plasmablasts-plasma cells but appear to represent slightly different stages of B cell differentiation. Thus, the U-1958 has plasma cell morphology, expresses only PCA-1 and OKT-10 but no other B cell antigens, and secretes 1.5 micrograms/mL of IgG/10(6) cells/24 hours. The U-1957 has plasma cell morphology and expresses Fc receptors and the LB-1 antigen in addition to the PCA-1 and OKT-10 antigens. This line produces only minimal amounts of IgG, which appears not to be secreted. The U-1996, finally, is a kappa light chain producer, has a plasmablast morphology, and expresses LB-1 in addition to the PCA-1 and OKT-10 antigens. All three cell lines are chromosomally heterogeneous and contain several markers with a 14q+ abnormality as a common characteristic abnormality. These new myeloma lines have been in continuous culture for approximately 3 years and are instrumental in studies of various aspects of the biology of human myeloma.

Aged↗

The use of a quantitative assay in endotoxin testing.

By utilizing Limulus Amebocyte Lysate (LAL) and a chromogenic peptide substrate it is now possible to determine endotoxin concentrations quantitatively down to 10 EU/L (1 pg/mL) in a two stage assay. The optimal reaction conditions found for the two stages of the method, the endotoxin reaction with LAL and the measurement of the activation with the chromogenic substrate, are briefly described. The properties of the final kit reagents have also been investigated and the results are included. Finally, the usefulness of the present method is demonstrated by results obtained from testing therapeutical products as well as clinical plasmas. Some factors which may be critical in the performance of the assay are discussed.

Animals↗

Identification of a cell-surface glycoprotein mediating cell adhesion in EBV-immortalized normal B cells.

Phorbol ester treatment markedly enhanced aggregation of Epstein-Barr virus (EBV)-immortalized normal B cells. Monoclonal antibody (MAb) 60.3, recognizing a leukocyte common antigen, completely inhibited intracellular adhesion, whereas MAbs reacting with leukocyte common antigen T200, C3b receptor, T-cell-associated antigen TA-I, C3d (EBV) receptor, brain-granulocyte/T-lymphocyte antigen, transferrin receptor, surface immunoglobulin, Class-I or Class-II transplantation antigens or a B-cell-specific antigen (BI) showed no inhibitory effect. Both the spontaneous and phorbol-ester-enhanced cell aggregations were similarly inhibited by Fab fragments made from antibody 60.3. Phorbol esters also enhance binding between EBV-immortalized normal B cells and autologous or allogeneic blood mononuclear cells depleted of B lymphocytes. This process, which is independent of immunity to EBV, was similarly blocked by the antibody fragments. Antibody 60.3 precipitated 3 non-covalently associated surface glycopolypeptides with apparent MW of 90, 130 and 160/kDa from EBV-infected B cells. Although dissociation of a similar protein complex from granulocytes by sodium dodecyl sulfate treatment clearly indicated the presence of the epitope on the smallest component, the same treatment did not dissociate the protein complex from EBV-immortalized normal B cells. It is thus concluded that the 90-kDa glycopolypeptide, either alone or associated with the larger glycopolypeptides, mediates cell adhesion of the B cells.

Animals↗

Internal chain cleavage and product heterogeneity during Edman degradation of isosteric peptide analogs lacking the alpha-carbonyl function.

A synthetic peptide analog, with one peptide carbonyl group replaced by a methylene bridge, was submitted to structural analysis by Edman degradation. Multiple cleavages were obtained in the first cycle, due to phenylthiocarbamylation of the internal secondary amine as well as spontaneous alkaline cyclization and subsequent recoupling with the Edman reagent. Three fragments from cleavage of the peptide analog after a single Edman cycle were purified by reverse-phase high-performance liquid chromatography. The results support previous observations in a novel combination. The reactions may also be important with native polypeptides since non-quantitative alkaline cyclization now encountered can mimic apparent N-terminal heterogeneity in agreement with earlier data, while quantitative cyclization can mimic loss of N-terminal residues.

Alkylation↗

Amplification of the N-myc oncogene in an adenocarcinoma of the lung.

c-myc oncogene is the most extensively studied member of the myc gene family, which now consists of three characterized members, namely the c-myc, N-myc, and L-myc genes. Deregulation owing to amplification and/or rearrangements of the c-myc gene have been described in a variety of human malignancies. Several neuroblastomas have amplifications of the N-myc genes. The c-myc, N-myc, or L-myc oncogenes are also found amplified in different cell lines from small cell carcinomas of the lung. In this study, we have examined the c-myc, N-myc, and c-erbB oncogenes in 34 clinical and autopsy tumor specimens representing various histopathological types of human lung cancer, including nine small cell lung cancers. A 30-fold amplification of the N-myc gene was found in a tumor histopathologically and histochemically verified as a typical adenocarcinoma. No amplifications of the c-myc or c-erbB oncogenes were seen in any of the tumors. In the DNA of one small cell carcinoma, an extra c-myc and N-myc cross-hybridizing restriction fragment was observed, possibly owing to an amplification of a yet uncharacterized myc-related gene.

Adenocarcinoma↗

Production of chemokinetic inhibitory factor (CIF) by normal blood and spleen B lymphocytes.

We have recently reported the partial purification and characterization of of a new lymphokine, the heat-labile chemokinetic inhibitory factor (CIF) which inhibits neutrophil movement. We have also shown that this lymphokine is produced and secreted by cultured B-chronic lymphocytic leukaemia (CLL) cells in vitro. The present study shows that highly purified resting normal B lymphocytes from blood and spleen have the capacity to produce CIF spontaneously. After activation with anti-IgM or EBV-infection the lymphocytes produced a number of other factors, heat-stable chemokinetic inhibitory factors and heat-labile chemokinetic enhancing factors. Supernatants from a collection of human B-cell lines representing different stages of B-cell differentiation were also investigated. None of these cell lines produced CIF. The present results show that the production of CIF is not restricted to the malignant B-CLL cell but is also produced by a subset of normal blood and spleen B cells.

B-Lymphocytes↗

Phorbol ester-induced production of beta-2-microglobulin in B-CLL cells: relation to IgM secretory response and disease activity.

Earlier studies have indicated that serum beta 2m levels correlate with the disease activity, estimated tumour cell mass and prognosis of CLL. We have therefore analysed the spontaneous and phorbol ester (TPA)-induced capacity of CLL cells to produce beta 2m in vitro in relation to disease activity. Cell cultures (greater than 90% B cells) from 15 patients with active disease contained significantly higher (P less than 0.001) levels of beta 2m (0.22 +/- 0.09 mg/l) than cultures from 17 patients with inactive CLL (0.08 +/- 0.06). When TPA-induced CLL cell cultures were compared, this difference was even more striking (0.48 +/- 0.18 versus 0.13 +/- 0.09). The capacity of TPA-treated B-CLL cells to export beta 2m was positively correlated with their capacity to secrete monoclonal IgM (r = 0.73; P less than 0.001). Cell depletion experiments showed that the beta 2m export by B-CLL cells is enhanced by accessory T cells. Four individual CLL patients were followed for 14 months and repeatedly investigated for signs and symptoms of active disease, and the CLL cells were tested for in vitro production of beta 2m. Fluctuations in the clinical activity of the leukaemia were paralleled by similar switches in CLL cell production of beta 2m.

Adolescent↗

The chemokinetic inhibitory factor derived from chronic lymphocytic leukaemia cells. Partial purification and characterization of a new lymphokine.

We have recently described a heat-labile and cell-directed neutrophil migration inhibitory activity that is present in serum from patients with chronic lymphocytic leukaemia (CLL). The inhibitory activity is produced and secreted by CLL cells in vitro. In the present study the inhibitory activity was partially purified from short-term cultures of monoclonal leukaemic B-CLL cells. On gel filtration the calculated molecular weight was apparently 30,000. By anion exchange chromatography, the inhibitory factor was recovered in the fractions that eluted with 0.3 mol/l NaCl. The active material applied to preparative agarose gel electrophoresis migrated towards the anode. The inhibitory factor was totally destroyed by trypsin. In addition it bound to concanavalin A-Sepharose. These properties indicate that the inhibitory factor is a glycoprotein. Antibodies against the isolated inhibitory factor were raised in rabbits. CLL serum was separated by means of gel filtration and the inhibitory activity was recovered in the pool with a molecular weight of approximately 30,000. The activity was completely neutralized by the antibodies raised against the CLL-cell-derived inhibitor, indicating the similarity between this and the serum-derived inhibitor. We have shown the existence of a new lymphokine, derived from B-CLL cells, in serum from patients with CLL.

Cell-Free System↗

Production of beta 2-microglobulin by chronic lymphocytic leukaemia cells in vitro.

The in vitro production of beta 2-microglobulin (beta 2m) by leukaemic cells was studied in 22 patients with chronic B-lymphocytic leukaemia (CLL). In addition, the concentration of beta 2m in serum (S-beta 2m) was determined and expressed as percent of the upper normal limit, after a correction for elevated S-Creatinine values. Patients with progressive disease usually had CLL cells with a high rate of in vitro synthesis and an increased S-beta 2m. This was not found in patients with non-progressive disease. The in vitro synthesis of beta 2m X the lymphocyte count correlated with S-beta 2m in the total material (r = 0.65). The increased S-beta 2m frequently observed in CLL may therefore originate from the tumour cells. Hence, S-beta 2m is promising as a clinically useful tumour cell-associated marker in CLL.

Aged↗

The effect of alpha and gamma-interferon on proliferation and production of IgE and beta 2-microglobulin in the human myeloma cell line U-266 and in an alpha-interferon resistant U-266 subline.

An IFN-resistant subline (U-266r alpha) was established from the IFN-alpha-sensitive myeloma cell line U-266 by subculturing U-266 cells with increasing doses of INF-alpha. The U-266r alpha secreted IgE at a higher rate than the U-266 (7.2 X 10(-13) g/c/8 h as compared to 3.3 X 10(-13) g/c/8 h). The 2 cell lines were found to be equally high producers of beta 2m (9.2 and 9.6 X 10(-13) g/c/8 h). The U-266 produced 2.9 times less IgE and 5 times more beta 2m compared to the initial production rates at establishment. INF-alpha and recombinant IFN-alpha 2 (rIFN-alpha 2) inhibited proliferation and concomitantly decreased the rate of IgE and beta 2m secretion in U-266 but not in U-266 IFNr alpha, which in contrast was slightly stimulated by IFN-alpha with respect to growth, IgE and beta 2m secretion. In addition, IFN-alpha at a concentration of 100 U/ml was shown to decrease the IgE and beta 2m production without exerting more than minimal cytotoxicity on U-266 cells. No antiproliferative effect was found for IFN-gamma or recombinant IFN-gamma (rIFN-gamma) on either of the 2 cell lines. IFN-gamma and rIFN-gamma were, however, found to stimulate the production of beta 2m. Our results show that the U-266 and the derived IFN-alpha-resistant subline can be used as models for studying some of the biological effects of IFN-alpha and -gamma in vitro. The clinical implications of these in vitro results, in particular the usefulness of serum determinations of immunoglobulin and beta 2m concentrations for monitoring the tumor cell mass, are discussed.

Cell Division↗