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N S Andersen

Publications and source records attributed to N S Andersen.

12 recordsLinked to original sources
PubMed2006

Immunoglobulin class-switch recombination occurs in mantle cell lymphomas.

Mantle cell lymphoma (MCL) is an IgM-expressing B cell lymphoma that originates from naive B cells and responds poorly to chemotherapy. We show here that several MCLs harbour isotype-switched subclones. Similar to the situation in normal B cells, in vitro stimulation of MCL cell lines with CD40 ligand (CD40L) and interleukin-4 induced expression of activation-induced cytidine deaminase (AID) and germline transcription at the immunoglobulin heavy chain gene locus. Additionally, the occurrence of switch-circle transcripts and mature IgG transcripts after stimulation indicated ongoing class-switch recombination in mantle cell lymphoma cell lines. Furthermore, stimulation of primary MCL cells in vitro induced expression of class-switched IgG mRNA in the tumour cells. Our data indicate that mantle cell lymphomas have retained the ability to undergo class-switch recombination if appropriate stimuli, such as the CD40 ligand, are provided.

CD40 Antigens↗
PubMed2005

Low level of gene flow from cultivated beets (Beta vulgaris L. ssp. vulgaris) into Danish populations of sea beet (Beta vulgaris L. ssp. maritima (L.) Arcangeli).

Gene flow from sugar beets to sea beets occurs in the seed propagation areas in southern Europe. Some seed propagation also takes place in Denmark, but here the crop-wild gene flow has not been investigated. Hence, we studied gene flow to sea beet populations from sugar beet lines used in Danish seed propagation areas. A set of 12 Danish, two Swedish, one French, one Italian, one Dutch, and one Irish populations of sea beets, and four lines of sugar beet were analysed. To evaluate the genetic variation and gene flow, eight microsatellite loci were screened. This analysis revealed hybridization with cultivated beet in one of the sea beet populations from the centre of the Danish seed propagation area. Triploid hybrids found in this population were verified with flow cytometry. Possible hybrids or introgressed plants were also found in the French and Italian populations. However, individual assignment test using a Bayesian method provided 100% assignment success of diploid individuals into their correct subspecies of origin, and a Bayesian Markov chain Monte Carlo (MC MC) approach revealed clear distinction of individuals into groups according to their subspecies of origin, with a zero level of genetic admixture among subspecies. This underlines that introgression beyond the first hybridization is not extensive. The overall pattern of genetic distance and structure showed that Danish and Swedish sea beet populations were closely related to each other, and they are both more closely related to the population from Ireland than to the populations from France, the Netherlands, and Italy.

Bayes Theorem↗
PubMed2002

A Danish population-based analysis of 105 mantle cell lymphoma patients: incidences, clinical features, response, survival and prognostic factors.

This study presents the first large clinical analysis of 105 unselected mantle cell lymphoma (MCL) patients diagnosed from 1992 to 2000 in a well-defined Danish population. The annual incidences were 0.7/100000 for men and 0.2/100000 for women, with no significant change during the study period. Of 97 evaluable cases, 43% achieved a complete response (CR) after initial therapy. The median disease-free (DFS) and overall survival (OS) rates were 15 and 30 months, respectively. In multivariate analysis, splenomegaly (P=0.002), anaemia (P=0.0001) and age (P=0.002), but not the international prognostic index (IPI) and the Ann Arbor staging system, had an independent impact on survival. Moreover, in a sub-analysis of 45 younger MCL patients (<65 years), a trend towards an OS plateau of 58% was observed in cases without splenomegaly and anaemia (n=29). Thus, in contrast to previously suggested prognostic factors, these variables may prove useful for clinical decisions in a significant subset of MCL patients.

Age Distribution↗
PubMed2000

Soluble CD40 ligand induces selective proliferation of lymphoma cells in primary mantle cell lymphoma cell cultures.

Interaction between CD40 and the CD40 ligand (CD40L) is critical for the survival and proliferation of B cells during immunopoiesis. However, the role of CD40L in the pathogenesis of malignant lymphomas is ambiguous. Primary mantle cell lymphoma (MCL) cells were cultured in the presence of recombinant human CD40L trimer (huCD40LT), and a significant time- and dose-dependent induction of DNA synthesis was observed in thymidine incorporation assays (n = 7, P <.04). The maximal rate of DNA synthesis was reached at huCD40LT doses of 100 ng/mL and above after 4 days of culture, but a significant increase of DNA synthesis was detected already at doses of 1 ng/mL (P =.03). HuCD40LT never inhibited the basal level of DNA synthesis. These findings established 400 ng/mL of huCD40LT for 4 days as standard conditions in the system. Under these conditions, huCD40LT significantly increased the proportion of cells in the S/G(2)/M phases of the cell cycle in 4 of 7 studied cases, while the fraction of apoptotic cells remained unchanged (n = 7). HuCD40LT also induced expression of CD80/B7-1, CD86/B7-2, and CD95/Fas and up-regulated the expression of HLA-DR (n = 6). With the use of bromodeoxyuridine incorporation in triple-color flow cytometric analysis, it was found that huCD40LT induced cell-cycle progression in light chain-restricted cells only, of which a median of 14% (range, 0.5% to 29%; n = 4) returned to G(0/1) phase DNA content after bromodeoxyuridine incorporation, demonstrating completion of at least one cell cycle in the presence of huCD40LT. Thus, primary clonal MCL cells are activated and can proliferate in the presence of huCD40LT as a single agent.

CD40 Antigens↗
PubMed1999

Linear reduction of clonal cells in stem cell enriched grafts in transplanted multiple myeloma.

In 30 patients with multiple myeloma who were scheduled for peripheral blood stem-cell transplantation, a quantitative analysis of the stem cells following enrichment by anti-CD34 was carried out. To detect the cells of the specific myeloma clone, polymerase chain reaction (PCR) was performed using unique allele-specific oligo primers for the immunoglobulin heavy chain rearrangement. The clonogenic cells before and after stem-cell enrichment, were quantified by a limiting dilution assay and a highly sensitive semi-nested PCR combined with a real-time quantitative PCR. In order to accomplish a statistically adequate end-point analysis, a large number of PCR analyses (40 per sample) were performed. By this technique the lowest detection limit observed was one myeloma cell per 106 cells. Myeloma cells were detected in 29/30 samples from the CD34-enriched fraction. The CD34 selection procedure resulted in a median 28-fold enrichment of CD34+ haemopoietic precursor cells. The stem-cell selection reduced the median concentration of clonal cells per million total cells by half, with a highly significant linear relationship between the number of myeloma cells before and after stem cell enrichment. The median depletion of clonal cells by the overall procedure was 2.15 log units, corresponding to a reduction of the total quantity of clonal cells reinfused into the patients by at least 99.3%. We conclude that CD34+ cell enrichment led to a reliable tumour cell depletion of the order of 2 log, which may not be sufficient since the total number of tumour cells in the leukapheresis product was 7.2 log (median).

Adolescent↗
PubMed1998

[Autoantibodies against coagulation factor VIII].

Autoantibodies towards coagulation factor VIII is a rare disease, incidence 1 pr. 2.5-5 million/year. The symptoms are most often subcutaneous or intramuscular haemorrhages or uncontrollable bleeding after minimal traumas. Screening tests show prolonged activated partial thromboplastin time, normal prothrombin time and thrombocyte count. Production of autoantibodies is controlled by prednisolone which may be supplemented with chemotherapy, i.e. azathioprine. Bleeding can be controlled by using coagulation factor concentrates that bypass factor VIII. If diagnosed early, there is a good chance of both stopping bleeding and suppressing autoantibody production. In order to be able to detect patients at risk of having factor VIII autoantibodies, it is recommended to screen all bleeding patients using activated partial thromboplastin time, prothrombin time and thrombocyte count. All patients showing isolated prolonged activated partial thrombin time should be referred to a laboratory specialized in coagulation problems for immediate evaluation.

Autoantibodies↗
PubMed1998

BEAM+autologous stem cell transplantation in malignant lymphoma: 100 consecutive transplants in a single centre. Efficacy, toxicity and engraftment in relation to stem-cell source and previous treatment.

One hundred consecutive patients with malignant lymphoma treated with high-dose chemotherapy and autologous stem cell transplantation, followed at least 1 yr post-transplant, are reported, 68 with non-Hodgkin's lymphoma and 32 with Hodgkin's disease. At transplant, 23 patients were in first remission, 69 in later chemosensitive disease and 8 were chemotherapy resistant. Based on previous treatment and stem-cell source, the patients were subdivided into 3 cohorts: BMT1: bone-marrow harvest and transplant after > or =3 treatment regimens (38 patients); BMT2: bone marrow harvest and transplant after less than 3 treatment regimens (24 patients); PBSCT: peripheral-blood stem cell transplant (38 patients, 5 of these with CD34+ cell selected PBSC). The 4-yr survival and progression-free survival of all patients was 45 and 40%, respectively. Forty-one patients have died, 27 of lymphoma, evenly distributed in the cohorts. Fourteen treatment-related deaths occurred, 13 of these in the BMT1 cohort, significantly more than in the other cohorts (p=0.001). In univariate survival analysis cohort, age, disease status at transplant and number of previous treatment regimens were significant. In multivariate survival analysis cohort, age and sex were independently significant, women having a shorter survival. The patients transplanted with unselected PBSC had significantly shorter duration of pancytopenia and hospital stay than the otherwise comparable BMT2 patients, but their progression-free survival was identical. We confirm that high-dose therapy with autologous stem cell transplant from blood or bone marrow in not-too-heavily pretreated patients is a safe procedure but will cure only half the patients.

Adult↗
PubMed1997

Failure of immunologic purging in mantle cell lymphoma assessed by polymerase chain reaction detection of minimal residual disease.

To assess the clinical significance of minimal residual disease (MRD) detection by polymerase chain reaction (PCR) we analyzed samples from 26 patients with mantle cell lymphoma (MCL) who had undergone bone marrow transplantation (BMT) at the Dana-Farber Cancer Institute. The BCL-1/IgH translocation and clonally rearranged Ig heavy chain genes (IgH) provided molecular markers for detection and follow-up of MRD by polymerase chain reaction (PCR) amplification in 19 of the 26 (73%) MCL patients studied. IgH gene sequencing analysis showed somatic mutations in MCL that are characteristic of an antigen driven process suggesting that, in MCL, the final malignant transformation occurs in a mature B cell. Of the 19 patients with a PCR amplifiable marker, 17 underwent autologous, 1 an allogeneic, and 1 a syngeneic bone marrow transplantation (BMT). All patients had PCR-detectable MRD in the bone marrow (BM) at the time of BMT, irrespective of any history of histological BM involvement. In contrast to other B-cell malignancies, we found that immunological purging with complement-mediated lysis eradicated PCR-detectable MCL in only two patients. Moreover reinfusion of MRD was associated with a poor outcome. More than half of the patients undergoing autologous BMT had relapsed by the time of restaging at 2 years after autologous BMT. In four MCL patients in whom no residual lymphoma was reinfused, including the allogeneic and the syngeneic BMT, only one patient relapsed. Persistence of MRD detection after BMT was also associated with a high probability of relapse, although one patient did not have PCR-detectable MRD in peripheral blood or BM before relapse at nodal sites. We conclude that PCR amplification of disease-specific markers is a feasible and sensitive method to assess MRD and its clinical significance in patients with MCL. Moreover, PCR amplification provides a tool to evaluate modifications of purging and stem cell collection procedures that may be required for the management of this otherwise incurable disease.

Adult↗
PubMed1996

[Acquired coagulation factor VIII deficiency. A 4-year survey of patients at the East Danish Hemophilia Center].

An East Danish population of acquired haemophilia A (factor VIII inhibitors) patients are described in a retrospective survey. Fifteen patients attended the centre during the period 1981-1994. The epidemiology, clinical presentation, time from début until diagnosis and response to treatment are presented. Acquired factor VIII inhibitors are rare and without treatment the disease has a high mortality and morbidity. Inhibitors mostly develop among the elderly, independent of sex and almost half have no known underlying disease. When the diagnosis is clear, bleedings may be controlled and the patient may be cured by treatment that eliminates the inhibitor. Time until diagnosis varies a lot, for some patients it takes years. It is therefore important to be aware of the disease, so that time with risk of fatal bleeding is shortened as much as possible.

Adult↗
PubMed1996

[Autologous stem cell transplantation. From bone marrow to selected blood stem cells: 100 consecutive procedures at a single center].

One hundred consecutive autologous stem cell transplants are reported: Non-Hodgkin's lymphoma 51 cases, Hodgkin's disease 27 cases, acute leukaemia 14 cases, multiple myeloma seven cases and chronic myeloid leukaemia one case. Most patients were in their second or later remission. The overall three-year survival for all patients was 60% and the three-year disease-free survival was 50% for lymphoma patients and 30% for acute leukaemia patients. The dominant source of stem cells was bone marrow during 1993, but from 1994 it has been peripheral blood, now totalling 33 cases. There were 12 toxic deaths, all among patients who were heavily treated before bone marrow harvest and transplantation. The patients transplanted with blood stem cells had significantly shorter duration of pancytopenia, and hospital stay, but their disease-free survival was not longer than that of a comparable group of bone marrow transplanted patients. Six patients were transplanted with purified CD34+ cells (selected by avidity column (Ceprate (R)), and had duration of thrombocytopenia and hospital stay similar to the patients transplanted with unmanipulated blood stem cells, but slightly longer duration of neutropenia. We conclude that high-dose therapy with autologous stem cell transplantation in not too heavily pretreated patients is a safe procedure irrespective of the source of stem cells.

Adolescent↗