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E Dickmeiss

Publications and source records attributed to E Dickmeiss.

At least 37 records · Page 2Linked to original sources
PubMed1997

The immunodeficiency after allogeneic bone marrow transplantation in man: role of cytokines.

The effect of various cytokines including rIL-1, rIL-2, rIL-3, rIL-4, rIL-6, and growth factors including rNGF, rILGF and rEPGF on the post transplant immunodeficiency after allogeneic bone marrow transplantation was explored in 8 patients. The results show that neither cytokine alone was able to increase the proliferative capability in post transplant lymphocytes, however, when added in conjunction a significant increase in PHA driven proliferation was noted. Any significant lack of growth factors is probably not the only cause of immunodeficiency post transplant, since addition of any of these compounds did not have any influence on the lymphocyte proliferation, and so the data presented here suggest that therapeutic application of any of the investigated cytokines or growth factors to such patients is unlikely to be successful in overcoming the defects of T cell function post grafting.

Acquired Immunodeficiency Syndrome↗
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↗
PubMed1996

Immunodeficiency after allogeneic bone marrow transplantation in man: the role of antigen presenting cells.

We investigated the proliferative response of donor T cells to phytohemagglutinin (PHA) presented by donor non-T cells in 7 patients after allogeneic bone marrow transplantation. Compared with the cellular response in the healthy marrow donors, T cell proliferation was found to be deficient in every recipient, from 130 to 739 days after grafting. Results of cell mixing experiments showed that the non-T cells of the patients were as capable as healthy donor non-T cells in presenting PHA to normal donor T cells. However, T cells from patients did not proliferate after substituting donor non-T cells for non-T cells from patients. This inability of T cells to proliferate was most likely the result of ineffective interactions among T cell subsets in patients after allogeneic bone marrow transplantation.

Adolescent↗
PubMed1996

Cytotoxic T cell activity after HLA-mismatch bone marrow transplantation.

Six patients with various hematologic diseases were treated with HLA-haploidentical bone marrow mismatched for 1-2 loci at the disparate chromosome with a relative response in the mixed lymphocyte reaction (MLR) ranging between 0.04 and 0.96 (median 0.27). Thirty to 371 days after bone marrow grafting, patient lymphocytes (of donor origin) were tested for reactivity in mixed lymphocyte culture (MLC) and cell mediated lympholysis (CMLy) to lymphocytes from the host (cryopreserved before grafting), the marrow donor, and unrelated individuals. After grafting, Lymphocytes from the patients showed a host-specific decrease in proliferation and in cytotoxic response (%51Cr release in a standard chromium release assay), when compared to the pretransplant host-specific donor response, whereas the responses towards third party cells were unaffected. This host-specific unresponsiveness after HLA-mismatch bone marrow transplantation is compatible with a clonal deletion theory and might be the reason that this procedure is at all possible.

Adolescent↗
PubMed1995

Defective natural immunity: an early manifestation of human immunodeficiency virus infection.

Cytotoxicity mediated by natural killer (NK) and lymphokine-activated killer (LAK) cells may be of significance in host defense against viral infections. This study included 347 patients infected with human immunodeficiency syndrome virus (HIV) type 1 and 110 controls. The NK cell activity, either unstimulated or stimulated with interferon-alpha (IFN-alpha) or interleukin-2 (IL-2), and the LAK cell activity were suppressed in patients, but the NK/LAK cell activity did not differ between patients with AIDS and patients without AIDS. However, the IFN-alpha-stimulated NK cell activity and LAK cell activity were reduced in patients with symptoms of HIV disease (CDCIV) when compared with asymptomatic patients (CDCII+III). When the data were analyzed by multiple linear regression, the percentage of CD4+ cells had a positive effect on these two parameters in patients without AIDS, whereas the percentage of CD4+ cells had no significant effect on unstimulated and IL-2-stimulated NK cell activity in these patients. In controls and AIDS patients, the percentage of CD4+ cells had no effect on NK/LAK cell activity in multiple linear models. The total number of CD16+ cells was low in patients compared to controls, whereas the percentages of CD16+, CD56+, and CD16+CD56+ were either normal or elevated. Therefore, the decrease in NK cell subpopulations did not contribute to the observed depression in NK/LAK cell activity in vitro. It is concluded that natural immunity is suppressed in HIV-seropositive patients primarily because of a qualitative defect of the NK/LAK cells. This qualitative defect includes a reduced responsiveness to IFN-alpha, which is progressive until the onset of symptoms, and possibly related to the loss of CD4+ cells.

Adult↗
PubMed1995

Phage display used for gene cloning of human recombinant antibody against the erythrocyte surface antigen, rhesus D.

A novel phage display system has been developed for PCR amplification and cloning of the Fab fragments of human immunoglobulin genes. Using this system, we have cloned an antibody from a mouse-human hybridoma cell line directed against the erythrocyte antigen rhesus D. Intact erythrocytes were used for absorption of the Fab phages. Soluble Fab fragments produced from the cloned material showed identical performance to the parental antibody in agglutination assays. Gel filtration confirmed that the Fab fragment consists of a kappa-Fd heterodimer. The successful use of intact cells for selection of specific Fab phages demonstrates that it is possible to by-pass purification of the antigen of interest. Comparison with published germline sequences demonstrated that the immunoglobulin coding regions had the highest homology to the VH 1.9III and V kappa Hum kappa v325 germline genes, respectively.

Amino Acid Sequence↗
PubMed1994

In vitro evaluation of a new filter for leucocyte depletion of platelet concentrate during component preparation.

A newly developed filter for prestorage leucocyte depletion of platelet concentrates (PC) was studied. The filter is designed for leucocyte depletion during the preparation of the pool PC from platelet rich buffy coats. In all the leucocyte depleted PC (LD-PC) leucocyte depletion was satisfactory. 19 of 20 units of LD-PC had a leucocyte content below 3 x 10(5) per PC and 1 contained 8 x 10(5) leucocytes. The standard PC contained 2.53 x 10(8) (0.87 x 10(8)-15.3 x 10(8); n = 20) leucocytes per PC (median and range). The quality of the LD-PC was evaluated by measuring platelet activation, platelet morphology, and pre- and poststorage pH. There were no differences in any of the parameters studied.

Blood Platelets↗
PubMed1993

Defective T-cell stimulatory pathways in patients after allogeneic bone marrow transplantation (BMT) in man.

Immunological reconstitution after allogeneic bone marrow transplantation in man is characterized by a decreased lymphocyte transformation response to various mitogens and antigens during a period of from months to years. One reason for the decreased proliferative capability could be an inverted CD4/CD8 ratio; however, the present investigation demonstrates that this is not the only explanation for the immunodeficiency, since the CD4 as well as the CD8 subset, when studied in isolation, have qualitative defects, as evidenced by a reduced response of both subsets to stimulation with PHA, anti-CD2 and anti-CD3 MABs. The reason for the qualitative defect is unknown but a distorted composition of the CD4+ as well as the CD8+ T-cell subsets is suggested by the present investigations. We also observed that the PHA response was almost completely reconstituted one year after BMT, while the PWM response was still severely affected. The present study suggests that T-cell subsets which differ in their capacity to respond to PHA and PWM have different kinetics of reconstitution after BMT.

Adolescent↗
PubMed1991

[Diagnosis of HIV-infection].

Different methods have been developed for the diagnosis of HIV infection, i.e. detection of antibodies, antigen and proviral DNA. ELISA methods for detecting HIV-1 antibodies are widely used as screening assays. A sample which is repeatedly positive with ELISA is re-tested with a confirmatory test, e.g. western blot. Antibodies to HIV-1 are not detectable until 2-3 months after infection, but antigens may be detectable during the last weeks of this initial period, though they disappear with the appearance of the antibodies. In the later stages of HIV infection, HIV antigen is again detectable in a proportion of patients. Detection and quantitation of HIV antigen are used as indicators of disease progression and for monitoring the antiviral efficacy of therapeutic interventions. When no antibodies or antigens can be detected in persons suspected of having HIV infection, culture of HIV can be performed. For research purposes, detection of small amounts of proviral DNA can be made with polymerase chain reaction (PCR). The method is not yet applicable in routine diagnosis of HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Increased frequencies of the CD29 and CD57 markers and decreased frequency of CD45RA within CD4+ and CD8+ subsets after allogeneic bone marrow transplantation in man.

Two monoclonal antibodies, anti-CD45RA and anti-CD29, reciprocally divide the CD4+ and CD8+ lymphocytes into CD4+ CD45RA+, CD4+ CD29+, CD8+ CD45RA+ and CD8+ CD29+ subsets. The CD4+ CD45RA+, CD4+ CD29+ and CD8+ CD45RA+ possess suppressor-inducer, helper-inducer and suppressor-effector functions respectively. Since the role of these subsets has not been established after allogenic bone marrow transplantation we studied lymphocyte subpopulations in 12 patients 45-227 days after the procedure. The fraction of CD4+ lymphocytes was significantly (P = 0.0005) decreased to 20 +/- 9% versus 43 +/- 3% in controls. Within the CD4+ compartment, we found an increase in the fraction of CD4+ cells that co-expressed CD29 (CD29+/CD4+) to 92 +/- 10% versus 48 +/- 15% (P = 0.008) in controls and a concomitant decrease in CD45RA+/CD4+ to 16 +/- 12% versus 56 +/- 25% (P = 0.008). Patients were also noted to have an increase in the percentage of CD8+ lymphocytes to 41 +/- 5% compared to 23 +/- 4% in controls (P = 0.0004). Examination of the CD8+ subsets revealed a significant increase in the CD29+/CD8+ fraction to 97 +/- 3% versus 64 +/- 2% in controls (P = 0.008) and a decrease in the CD45RA+/CD8+ fraction to 36 +/- 11% versus 70 +/- 21% (P = 0.008). The number of cells co-expressing CD57 were also determined within the CD4+ and CD8+ subsets. In patients CD57+/CD4+ were increased to 29 +/- 7% versus 1 +/- 1% in controls (P = 0.04), and CD57+/CD8+ to 49 +/- 12% versus 23 +/- 9% (P = 0.02). Since CD29+ and CD57+ cells have a poor capability for IL-2 production and proliferation this shift in subset distribution may account for some of the defects in cellular immunity seen within the first year after allogeneic bone marrow transplantation.

Adolescent↗
PubMed1991

Ranitidine improves certain cellular immune responses in asymptomatic HIV-infected individuals.

Human immunodeficiency virus (HIV) infection is characterized by a progressive impairment in immunocompetence leading to severe opportunistic infections and malignancies. In a double-blind, placebo-controlled study, the potential impact of immunomodulation by oral ranitidine, 600 mg daily, for 28 days was studied in 18 HIV-positive patients (CDC group II). All were without clinical signs of infections and were not treated with other known immunomodulating agents. Several immunological parameters related to HIV infection were studied and confirmed to be impaired early in HIV infection. Spontaneous and in vitro interleukin-2- and interferon-alpha-stimulated natural killer cell activity improved in the ranitidine-treated patients in contrast to a decrease in nontreated patients (#p less than 0.03, #p less than 0.01, #p less than 0.02 between groups, respectively). Furthermore, T-cell blastogenesis to phytohemagglutinin stimulation and soluble interleukin-2 receptors in serum increased in ranitidine-treated patients compared with nontreated patients (#p less than 0.01). However, ranitidine treatment did not change CD4+ cell counts. Although the significant improvement in immunocompetence shown in this study is small, the present result indicates the need for further trials with immunomodulation by ranitidine in HIV-infected individuals.

Adult↗
PubMed1990

[Screening of Danish blood donors for hepatitis C virus antibodies].

In Denmark only 1-3 cases of transfusion-associated hepatitis NANB (TAH-NANB) are registered annually or about 1 case per 100,000 units transfused. Thus, the prevalence of blood donors with hepatitis NANB infection is estimated to be very low and measures to prevent TAH-NANB such as surrogate testing have not been considered to be worth while. The incidence of TAH-NANB, however, may be underestimated if cases are overlooked or not identified as transfusion-associated or if registration fails. The appearance of the anti-HCV test (Ortho) has clearly provided a more sensitive and specific tool for identifying blood donors, who may transmit hepatitis NANB. In the present study, we have determined the prevalence of anti-HCV in random Danish blood donors from 1989 (fresh serum samples) and 1982 (frozen serum samples). All donors were tested for ALT and anti-HBc. A prevalence of 0.3% anti-HCV positive blood donors was found in 1989 (2/600) as well as in 1982 (2/595). Thus, no change in the prevalence of HCV infected donors seems to have occurred in Denmark during these years. The anti-HCV prevalence of 0.3% in random blood donors is low but not negligible, and if the majority of the reactive donors identified are true positives, the epidemiologic pressure as to HCV infection probably equalizes the pressure as to HBV infection (0.1-0.2%) in people attending our blood banks to become donors. In a group of donors positive for surrogate markers (ALT greater than 40 U/l and/or anti-HBc) we found only 0.9% (2/225) anti-HCV positives.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Donors↗
PubMed1990

[Screening of donor blood for anti-HIV. Experiences from blood donor screening 1986-1988].

During the period 1986-1988, approximately 1,200,000 portions of blood were anti-HIV screened in Denmark. A total of 19 donors were found to be anti-HIV positive and no increase in the frequency of anti-HIV blood donors has been observed during this period. At a subsequent interview, nine out of these 19 donors (47%) were shown to have risk factors for HIV infection. During the same period, a total of 12 cases of transfusion-associated HIV infection were found at follow-up control of recipients of blood from previous donations from donors demonstrated to be positive after 1986. Four of the cases were demonstrated to be positive by blood donor screening and eight in other ways. Finally, five cases of transfusion-associated HIV infection in recipients have been reported where no positive donor could be identified. One case of HIV infection could be attributed to transfusion with screened anti-HIV negative blood. On the basis of information from blood donor screening, it is concluded that the risk that a screened anti-HIV negative blood portion in Denmark can transmit HIV infection is less than one per 400,000.

Blood Banks↗
PubMed1990

T-cell subset alterations and lymphocyte responsiveness to mitogens and antigen during severe primary infection with HIV: a case series of seven consecutive HIV seroconverters.

Seven consecutive patients who presented with a severe acute mononucleosis-like illness associated with HIV seroconversion were evaluated by T-cell subset enumerations and measurements of lymphocyte transformation responses to mitogens and antigen during both their primary illness and a 1-year follow-up period. We observed a characteristic pattern of response to primary HIV infection; initial lymphopenia was followed by CD8 lymphocytosis and inversion of the CD4:CD8 ratio. During follow-up, the CD8 count gradually returned to normal, whereas the CD4:CD8 ratio remained inverted because of a relatively low number of CD4 lymphocytes. Primary infection was followed by prolonged and severe cellular hyporesponsiveness to both mitogens and antigen. At the last follow-up, responses to pokeweed mitogen were still severely impaired, with a median 19% (range 7-50%) of that observed in healthy controls. We conclude that severe primary HIV infection may be followed by sustained lymphocyte hyporesponsiveness, a sustained low percentage of CD4 lymphocytes and sustained inversion of the CD4:CD8 ratio.

Adult↗