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Biomedical subjects

K Nilsson

Publications and source records attributed to K Nilsson.

At least 235 records · Page 13Linked to original sources
PubMed1988

Immunoglobulin synthesis in the human myeloma cell line U-266; expression of two immunoglobulin heavy chain isotypes (epsilon and alpha) after long-term cultivation in vitro.

A human IgE-producing myeloma has been cultivated in vitro as a continuous cell line (U-266) since 1968. Analysis of immunoglobulin production during early passages of the cell line demonstrated a high synthesis rate of monoclonal IgE. Analysis of late passages, cultivated after 1980, revealed a 3-6-fold lower rate of IgE secretion. This decrease was accompanied by the appearance of small amounts of IgA in the culture medium together with IgE. RNA was extracted from a late passage of U-266 and analyzed by Northern blotting, using epsilon and alpha-specific oligonucleotides as hybridization probes. The results showed the presence of epsilon as well as alpha-specific mRNA. Moreover the results demonstrated that the latter mRNA was derived from the alpha 2 locus and that the epsilon and the alpha 2-specific mRNA contained the same V region sequences. Southern blot analysis of DNA from the late passage of the U-266 cell line failed to reveal a recombinatory switch from the epsilon locus to the alpha 2 locus. The expression of alpha 2 is thus likely to be caused by differential splicing rather than by an isotype switch at the DNA level.

Cell Line↗
PubMed1988

Cytoplasmic pH is differently regulated in the monoblastic U-937 and erythroleukemic K-562 cell lines.

Regulation of cytoplasmic pH (pHi) of the human monoblastic U-937 and erythroleukemic K-562 cell lines was investigated. The apparent resting pHi, as assessed by the fluorescent pH probe quenel, were 6.61 and 6.75 for the U-937 and K-562 cells, respectively. When extracellular Na+ was substituted by equimolar choline+, pHi decreased by about 0.2 units. The protein kinase C activating beta-form of the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA; 10(-10) and 10(-7) M) induced a dose-dependent alkalinization in both cell types of 0.03-0.12 units, whereas the alpha-form was inactive. The response was detectable after about 2 min and reached steady-state 10-15 min later. In the K-562 cells the alkalinization was mediated by Na+/H+ exchange as it was accompanied by stimulation of H+ extrusion and abolished by Na+ removal. The TPA response in the U-937 cells, however, was unaffected by Na+ removal, not accompanied by H+-efflux, and thus unrelated to Na+/H+ exchange. Since electron microscopy indicated development of multivesicular bodies with an acidic interior, the alkalinization can probably be accounted for by an intracellular mechanism. Ionomycin (10(-5) M) induced a rapid increase in the cytoplasmic Ca2+ concentration of both cell types and this response was accompanied by acidification followed by a Na+-dependent recovery. In the U-937, but not in the K-562, cells this recovery was followed by a net alkalinization. It is concluded that both cell types possess a Na+/H+ exchange of importance for pHi but that this mechanism is regulated differently in the U-937 and K-562 cells.

Calcium↗
PubMed1988

Patterns of glycosidases in the histiocytic cell line U-937. Effects of agents inducing cell differentiation.

1. The cell bound glycosidases in sublines and clones of the histiocytic cell line U-937 have previously been shown to display characteristic patterns. 2. In this paper the effects of differentiation inducing agents upon glycosidase patterns of one subline, U-937 GTB, are presented. 3. Teleocidin, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), dimethyl-sulfoxide (DMSO), dihydroxyvitamin D3 and supernatants from mixed lymphocyte culture (MCL) all induce cellular differentiation of U-937 GTB. 4. Significant changes of the levels of cell bound glycosidases were seen after addition of inducing agents. 5. Alterations have been monitored as relative effects upon the absolute glycosidase activities and as effects upon selected ratios of different glycosidases. 6. The separate inducing agents show distinct enzyme patterns.

Acid Phosphatase↗
PubMed1988

Glycosidase and phosphatase activities in U-937 and some clones and sublines.

1. The activities of nine glycosidases, lysozyme and acid and alkaline phosphatases were compared in the histiocytic lymphoma cell line U-937 and a set of clones and sublines derived from this line. 2. The patterns of the different enzyme activities and selected enzyme ratios have been used as a method to distinguish between different clones and sublines. 3. Sublines with high lysozyme levels were rich in most cell-bound glycosidases. 4. During long-term growth distinct enzyme patterns of individual lines were preserved. 5. The enzyme pattern during a cell culture growth cycle was basically stable.

Acid Phosphatase↗
PubMed1988

Expression of the proenkephalin gene in human neuroblastoma cell lines.

Several human tumour cell lines were screened for secretion of proenkephalin-derived peptides with an antiserum directed to its N-terminus, Met-enkephalin-Arg6,Phe7 and for proopiomelanocortin-derived peptides with an antiserum to beta-endorphin. The neuroblastoma SK-N-MC cell line secreted Met-enkephalin-Arg6,Phe7-immunoreactive peptides in relatively high amounts into the culture medium, although processing was not complete and there was no evidence for free Met-enkephalin-Arg6,Phe7. Gene expression was confirmed by the presence of proenkephalin mRNA and proenkephalin-derived polypeptides in extracts of the SK-N-MC cells and also in the neuroblastoma SH-SY5Y cell line. In the latter cells, however, the expression was approximately 3 times lower, there was less processing of proenkephalin and no evidence for secretion.

Adrenal Gland Neoplasms↗
PubMed1988

Phorbol ester-induced terminal differentiation is inhibited in human U-937 monoblastic cells expressing a v-myc oncogene.

Induction of differentiation of the human monoblastic cell line U-937 in vitro by several physiologic and nonphysiologic inducers is accompanied by a rapid decrease in expression of MYC, the endogenous human myc protooncogene. To investigate whether this reduction is a prerequisite for terminal differentiation, we introduced a constitutively expressed v-myc gene into U-937 cells. The results show that constitutive expression of an avian v-myc oncogene does not interfere with phorbol 12-myristate 13-acetate-induced differentiation of U-937 cells early after stimulation. However, after 24 hr the differentiation process is reversed, as judged by a full recovery of the proliferative capacity and reexpression of the immature phenotype, within the next 2-4 days. We conclude that the terminal stage of macrophage differentiation is inhibited in U-937 cells constitutively expressing a v-myc oncogene.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1988

A new device for administration of nasal continuous positive airway pressure in the newborn: an experimental study.

During treatment with continuous positive airway pressure (CPAP), optimal re-expansion of lung units with minimal work of breathing is best accomplished when the airway pressure (Paw) is kept constant at the desired CPAP level throughout the entire breathing cycle. To achieve this, a new device was constructed in which CPAP was generated by a jet of fresh gas close to the nasal airway. The performance of the new device was investigated experimentally using a lung model which simulated the breathing pattern of a newborn. Paw, flow, and external work of breathing were measured at three CPAP levels, with and without controlled airway leakage. The new device was compared with a traditional continuous-flow CPAP system with standard nasal prongs. Despite a virtually constant pressure within the traditional system, Paw variations and external workload were considerably less with the new device, which was also less sensitive to airway leakage.

Administration, Intranasal↗
PubMed1988

Induction of basophilic differentiation in the human basophilic cell line KU812.

The potential for differentiation of the human basophilic leukaemia cell line KU812 was examined by means of a panel of physiologic and non-physiologic substances used as inducers. The phenotypic characteristics of non-induced KU812 cells included an immature morphology with scanty cytoplasmic granulation, expression of a low amount of high affinity, but no low affinity receptors (CD 23) for IgE, and a capacity for low-rate histamine synthesis. The differentiation process was characterized by a rapid (24 h) increase in histamine production a slower morphological maturation with the development of Alcian blue stainable granula demonstrable after 72 h. Concomitant with the phenotypic alterations, cell growth was inhibited. Differentiation in KU812 cells was inducible by Ara-C and to some extent by sodium butyrate, but not by dimethyl sulphoxide, retinoic acid, or gamma-interferon. Conditioned medium (CM) from cultured peripheral blood cells from atopic individuals and 18 out of 22 analysed glioma cell lines induced differentiation of the KU812 cells, whereas supernatant from only 1 out of 21 other cell lines, including carcinoma, melanoma, sarcoma, leukaemia, and normal fibroblasts had this activity. CM from the T-leukaemic cell line, Mo, also induced KU812 differentiation. A primary fractionation of the active substance from this cell line by reversed phase chromatography eluted the active substance at a concentration of 42-44% acetonitrile. Our present study has shown that the KU812 may serve as an appropriate model to study differentiation of basophils. In addition, its fast and specific response to biological factors makes it suitable as a biological assay for determination of active factor produced by atopic individuals.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1988

Different origins of IgA antibodies with various antigen specificities appearing in rat bile.

Eight lactating and seven non-lactating female rats were immunized in Peyer's patches (Pp) with Escherichia coli 06 carrying type 1 pili. Eight days later the thoracic duct was drained and bile was collected at the same time. During the lymph drainage in the lactating rats, the biliary IgA anti-pili antibodies decreased less than the anti-lipopolysaccharide (LPS) antibodies. The non-lactating rats showed only a very small difference in decrease between the anti-pili and the anti-LPS antibodies. Transfer of mesenteric lymph node cells from male donor rats immunized with the E. coli strain to syngeneic male recipients resulted in the appearance of both IgA anti-pili and anti-LPS antibodies in the bile. This is at variance with the results seen in lactating rats, where only biliary IgA anti-LPS is seen after similar cell transfer. In conclusion, the study shows that in lactating rats a larger proportion of biliary IgA anti-pili antibodies than anti-LPS antibodies is derived from extraintestinal sites, such as the mammary glands or the liver. Thus, this study confirms that the nature of the antigen influences the transfer of the secretory antibody response to different secretions.

Animals↗
PubMed1988

Aggressive behavior in hospitalized psychogeriatric patients.

The frequency and characteristics of aggressive and hostile behavior in 40 psychogeriatric inpatients was investigated using the Staff Observation Aggression Scale (SOAS). Most aggressive acts were directed towards nursing staff when providing help with activities of daily living. A positive correlation was found between age and the frequency of aggressive behavior, while severity was most strongly correlated to length of admission. A significant decrease in frequency was observed during the six weeks of observation. The causes of this decrease are discussed together with the implications for future studies on the treatment of aggressive behavior in this group of patients.

Activities of Daily Living↗
PubMed1988

IgE-producing low-grade non-Hodgkin lymphoma.

An unusual case of IgE-producing non-Hodgkin lymphoma (NHL) is presented. The patient's history included a 6-year period of increasing IgE level before a low grade NHL was diagnosed. The patient developed lymph node, skin, bone marrow and lung infiltrations. With a cytostatic combination therapy a temporary improvement was achieved, but the patient died from progressive disease after 2 yr. The morphological appearance of the tumour varied between that of LP immunocytoma and a centrocytic lymphoma. Immunophenotype studies showed intracytoplasmic IgE lambda in tumour cells and B-cell surface phenotype (BB-1 pos; OKT 10 pos; PCA weakly pos and SIgE lambda).

Aged↗
PubMed1988

Induction of IgM secretion by chronic B-lymphocytic leukaemia cells in serum-free medium: effects of interferon-alpha, -gamma and phorbol ester.

Serum-free culture conditions would be preferable when studying the cellular and molecular regulation of B lymphocyte activation, proliferation and differentiation. We describe here the morphological and functional differentiation of chronic B-lymphocytic leukaemia (B-CLL) cells from 10 patients cultured in serum-free medium. When exposed to the phorbol ester TPA, cells from 8/10 cases expressed blastoid morphology and secreted significant levels of monoclonal IgM. The addition of 0.5% newborn calf serum to the serum-free medium increased both the spontaneous and TPA-induced IgM secretion of B-CLL cells by a factor of 6 and 7, respectively. Compared with TPA, significant but lower levels of IgM secretion and morphological differentiation were observed with native purified leucocyte interferon-alpha (IFN-alpha) (6/8 patients), some batches of recombinant IFN-alpha 2 (5/8 patients) and recombinant IFN-gamma (4/8 patients) in a dose-dependent and specific manner. Preactivation of B-CLL cells with TPA or anti-mu antibody was not necessary for the IFN-induced functional maturation. Significant DNA synthesis was not observed with any of the inducers used. These studies show that B-CLL cells can be induced to differentiate under serum-free conditions in response to physiological and non-physiological ligands.

Aged↗
PubMed1988

Immunocytometric characteristics of a monoclonal antibody (Bra55) recognizing the leukocyte common antigen (LCA).

The immunofluorescence cytofluorometric reactivity pattern of monoclonal antibody Bra55 (IgG1) elicited with a non-T, non-B ALL cell line (REH), with a panel of human neoplastic hemopoietic cell lines (including non-T, non-B, T and myeloid leukemia cell lines) and with isolated peripheral blood lymphocytes, monocytes and granulocytes from healthy donors corresponded to the previously described microscopic immunofluorescence, ELISA, immunoprecipitation and immunocytochemic data indicating that this monoclonal antibody recognizes a 170-220 kDa cell surface glycoprotein (leukocyte common antigen) expressed selectively on hemopoietic cells. The purified, FITC-conjugated Bra55 monoclonal antibody was effectively inhibited in its binding to the surface of LCA-positive cells by reference anti-LCA monoclonal antibodies; no inhibition of this activity by LCA-unrelated monoclonal antibodies (such as anti-MHC class I and class II antibodies) was observed. These data confirm the previously reported hemopoietic cell specificity (anti-LCA, CD45) of the Bra55 monoclonal antibody.

Antibodies, Monoclonal↗
PubMed1988

Age retirement in women. I. General presentation.

Within the framework of a longitudinal population study of age retirement in women, the short-term consequences of retirement were studied in 116 municipally employed women in the city of Malmö (230,000 inhabitants) in southern Sweden half a year before and half a year after retirement. The women represented about 40 different occupations, mostly within the sectors of health care, social services and administration. The study comprised four main parts, namely health and discomfort, social psychology, dietary habits and body composition, and oral health. The present paper concerns a general presentation of the study including sampling procedures and analyses of non-response. The response rate was a little more than 70%. Only a few significant differences were observed between non-responders and responders, such as more working hours per week, and more frequently a negative attitude towards retirement in the non-responders after retirement. This longitudinal prospective study of the same cohort of women has so far shown that the general design, sampling procedure and general methods of data collection appear adequate and feasible. In general, the study population was representative of women about to retire from municipal employment in Sweden. Results from the different studies will be presented elsewhere. To illustrate not only the short-term effects of retirement we intend to reexamine the same women about 2 years after the retirement.

Dental Health Surveys↗
PubMed1988

Age retirement in women. II. Dietary habits and body composition.

Within the framework of a longitudinal study of municipally employed women in Malmö, Sweden, before and after retirement, comprising health, social, psychological, nutritional and odontological aspects, the dietary habits and body composition were evaluated. 116 women aged 62, 63 and 64 were included. A detailed dietary interview was performed by a nutritionist, anthropometric measurements were made, and body compartments were calculated after retirement with a new electrical impedance method. Average dietary intakes were relatively high, but variation was marked. Intake of energy and almost all nutrients showed a clear decreasing tendency from before to after retirement, despite an increase in body weight and waist measurement, indicating decreasing physical activity after retirement in these women. There was also an increasing consumption of pastry, potato chips and similar food items. One third of the women was below the recommended dietary allowances (RDA) regarding calcium and almost all women below the RDA regarding vitamin D. There are reasons to believe that the event of retirement in women might imply some dietary hazards.

Body Composition↗
PubMed1988

Cell cycle progression of B-chronic lymphocytic leukemia cells induced to differentiate by TPA.

The cell cycle transition and differentiation-associated surface antigen expression was studied in a clone of B cell chronic lymphocytic leukemia (B-CLL) with phenotypic properties similar to those of resting B lymphocytes. Differentiation was induced with TPA (12-O-tetradecanoyl-phorbol-13-acetate) and defined and quantitated by morphological and functional markers. Changes in the cell cycle position were determined by flow cytometry of acridine orange-stained cells. The uninduced B-CLL cells represented a homogeneous population with the same cell cycle position (GO) as resting normal peripheral blood lymphocytes. After five days of TPA stimulation, 56% of the B-CLL cells were found in G1A, 9% in G1B, and 3% in the S + G2/M phase, of which 2% was accounted to proliferating T cells. The cell cycle transition of the differentiating B-CLL cells was also examined using cell cycle-associated surface antigens as markers. HLA-DR and CD23 antigens were present already on noninduced cells. The former had a high constant expression, while the amount of CD23 increased upon induction. The 4F2 antigen was absent on noninduced cells but present on 86% of the induced cells. HH1 (CD37) was expressed by the majority of the cells before TPA treatment and decreased to almost undetectable levels within 24 hours. Two antigens related to late stages of the cell cycle, the interleukin 2 (IL 2; CD25) and the transferrin receptor, were present on about 20% of the induced cells. Experiments with enriched T cells showed that T but not B cells incorporated 3H-thymidine. Taken together these results and previous work on the induction of the protooncogene c-myc and c-fos suggest that this B-CLL clone represents GO cells that undergo differentiation without concomitant proliferation when exposed to TPA.

Antibodies, Monoclonal↗