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D Huhn

Publications and source records attributed to D Huhn.

At least 91 records · Page 5Linked to original sources

Sensitivity of multidrug-resistant tumor cell lines to immunologic effector cells.

The ability of malignant cells to survive exposure to cytotoxic agents is a major obstacle to cure in patients with cancer. Multidrug resistance and the expression of P-glycoprotein are emerging as a cause of chemotherapy failure. Immunologic effector cells such as lymphokine-activated killer (LAK) cells or cytokine-induced killer (CIK) cells are capable of killing a broad range of tumor cell lines or freshly isolated tumor cells. As demonstrated here, LAK, and CIK cells possess a high level of cytotoxic activity against tumor cell lines both resistant and sensitive to chemotherapeutic agents such as doxorubicin or vinblastine. CIK cells possessed a higher level of cytotoxic activity than LAK cells as determined by 51Cr release and a tumor colony assay. Monoclonal antibodies against P-glycoprotein did not block the lysis of tumor cells resistant to chemotherapy by CIK cells. In contrast, antibodies to LFA-1 and ICAM-1 blocked CIK cell-mediated tumor cell lysis. These data demonstrate that immunological approaches to cancer therapy may be useful in overcoming disease caused by drug resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Chemotherapy for patients with adenocarcinoma of the pancreas.

Adenocarcinomas of the pancreas are diagnosed at an advanced, non-curable stage in most patients. In addition to local relapse or progression, distant metastases determine the poor prognosis, resulting in a median survival of less than 6 months in most studies of patients with locally advanced or metastatic pancreatic cancer. None of the cytotoxic drugs available show impressive activity in treatment of this disease. Therefore, chemotherapy is not recommended in pancreatic cancer. In selected cases, 5-fluorouracil-based therapy - with or without simultaneous radiation - may result in tumor responses. With a once-a-week outpatient protocol of folinic acid and 5-fluorouracil, we observed a progression-free period from 15 to 42 weeks in nine of 19 patients treated without any serious adverse effects, confirming reports of the weak, but well-tolerated activity of this combination. To alter the prognosis for patients with advanced adenocarcinomas of the pancreas, new drugs with more activity have to be developed and tested in well-designed trials.

Adenocarcinoma↗

Immunotyping of blasts in human bone marrow.

The diagnostic potential of immunocytochemical investigation of human bone marrow has not been fully realized due to difficulties in morphological identifying of immunostained cells. We used an indirect immunoperoxidase technique after May-Grünwald-Giemsa staining for simultaneous morphological and immunocytochemical analysis of blasts in human bone marrow. Six healthy bone marrow donors were investigated. Most blasts I expressed CD34, CD38 and HLA-DR. Expression of c-kit (CD117) was observed on 42 +/- 9% of blasts I. Granulocytomonocytopoietic character was demonstrated by expression of CD13 (33 +/- 15%) and CD45RA (23 +/- 10%) and erythropoietic character was demonstrated by expression of CD36 (22 +/- 8%) and CD45RO (30 +/- 11%). A very low proportion of blasts I were Thy-1 and CD61 positive; 34 +/- 6% of blasts I expressed CD22, representing B lymphoid committed progenitors. CD3, CD15, and glycophorin A expression was not detected. Blasts II and III and proerythroblasts did not show CD34 positivity. We conclude that blasts I are morphologically identifiable cells with a high percentage of CD34, CD38, and HLA-DR positivity. They are a pool of committed progenitor cells for erythropoiesis, granulocytomonocytopoiesis, megakaryocytopoiesis, and B cell development. Blast II and proerythroblast represent the first morphologically identifiable cells of granulocytopoiesis and erythropoiesis.

ADP-ribosyl Cyclase↗

Discrimination of HLA-B27 alleles by group-specific amplification followed by solid-phase sequencing.

HLA-B27 is known to be highly associated with ankylosing spondylitis. Until now, nine B27 subtypes have been sequenced and may contribute in different fashions to ankylosing spondylitis. Additionally, the divergent subtypes may be of clinical importance in bone marrow transplantation with alternative donors. The purpose of this study was to determine the different subtypes of HLA-B27 by a direct sequencing approach. The typing strategy is based on a group-specific amplification of the second and third exon followed by automated fluorescence sequencing of the polymorphic regions. The extensive sharing of sequence motifs between the different B alleles made it impossible to specifically amplify the B27 group under the precondition of including all sequence variations necessary for a postamplification specificity step. Therefore, for setting up a direct sequencing approach of B27, co-amplified B alleles had to be taken into account. In order to get unambiguous sequencing chromatograms without any heterozygous positions, nested sequencing primers were used which selectively matched sequence motifs only present in the second and third exon of the amplified B27 alleles. This strategy allowed in all cases investigated a clear separation of the haplotypes, revealing unequivocal sequencing results. Using this method, we have investigated 93 B27-positive individuals. Sequencing identified the alleles B*2702, 2703, 2704, 2705, and 2707. B*2701, 2706, 2708, and 2709 were not represented in the population studied.

Alleles↗

Interference of blood leucocytes in the measurements of immature red cells (reticulocytes) by two different (semi-) automated flow-cytometry technologies.

Flow cytometrical methods have been introduced recently as an alternative to the enumeration of reticulocytes by microscopy. Two of these methods have gained widespread use in haematological practice; the multiparametric flow cytometer using thiazole orange staining (Retic-Count, FACScan) and the single-application reticulocyte counter using auramine-O staining (R-series, Sysmex). Several studies have emphasized the excellent correlations between microscopy and these techniques. The purpose of our study has been to examine the specificity of these automated devices with regard to cells classified as 'reticulocytes' and the effect that this may have on measures of reticulocyte maturity. Our results indicate that the specificity of reticulocyte measurements by both the Sysmex R-1000/-3000 and the Retic-Count system is relatively low. This is due to the presence of leucocytes amongst cells classified as reticulocytes. These leucocytes display intense staining with either dye, leading to an erroneous estimation of RMI (thiazole orange) and high fluorescence count (R-1000/-3000). This error is directly correlated with the leucocyte count. The basis for reticulocyte identification should be improved before automated estimation of reticulocyte maturation can be used in clinical practice.

Automation↗

Analysis for recovery and loss of mononuclear cells and colony-forming units granulocyte-macrophage during ex vivo processing of autologous bone marrow.

During ex vivo processing of autologous bone marrow (BM) substantial loss of stem and progenitor cells should be avoided to achieve rapid and sustained hematopoietic reconstitution after high-dose radio-/chemotherapy. We processed 25 autologous BM grafts with the Fresenius AS104 cell separator for cryopreservation and we determined recoveries for mononuclear cells (MNC) and colonyforming units granulocyte-macrophage (CFU-GM) in the BM concentrates. To identify cell loss in BM fractions not cryopreserved, we investigated the MNC and CFU-GM content of BM fat and BM blood. MNC and CFU-GM recovery yielded a mean ( +/- SEM) of 42 +/- 12 and 54 +/- 20% in the BM concentrate. BM fat showed a mean loss of 7 +/- 5% for MNC and 4 +/- 3% for CFU-GM, BM blood 30 +/- 12% for MNC and 13 +/- 13% for CFU-GM, respectively. CFU-GM recovery was significantly higher in the BM concentrate of patients with hematologic malignancy (HM) compared with patients suffering from germ cell cancer (GCC): 66 +/- 21 vs. 43 +/- 12% (p < 0.02). Seventeen patients (7 GCC, 10 HM) underwent high-dose chemotherapy or radio-/chemotherapy and were autografted with 0.8 +/- 0.2 x 10(8) MNC/kg and 3.7 +/- 2.0 x 10(4) CFU-GM/kg. All patients achieved engraftment with neutrophils > 0.5 x 10(9)/l at a mean of 14 +/- 6 days. We conclude that: (1) ex vivo processing of autologous BM with a mean of recovery of 42% for MNC and 54% for CFU-GM in the BM concentrate can result in a cell population capable of sustained hematopoietic reconstitution, (2) CFU-GM recovery is significantly higher in patients with HM than in patients with GCC and (3) 37% MNC and 17% CFU-GM represent in fact cell losses recovered from BM fractions not cryopreserved (BM fat, BM blood). Furthermore, it is likely that MNC and CFU-GM not recovered from BM concentrate, BM fat and BM blood are cell losses related to the cell separator.

Adolescent↗

Analysis of the p53 and MDM-2 gene in acute myeloid leukemia.

The MDM-2 (murine double minute 2) gene codes for a cellular protein that can bind to the p53 tumor suppressor gene product, thereby functioning as a negative regulator of p53. In order to define the role of the MDM-2 gene in the pathogenesis of human acute myeloid leukemia, the expression and the sequence of the MDM-2 gene were examined in samples of bone marrow and/or peripheral mononuclear cells of 38 patients by using immunostaining, polymerase chain reaction (PCR), single strand conformation polymorphism, and sequencing. Immunohistochemical staining detected a weak accumulation of the MDM-2 protein in AML patients of FAB classification M4 and M5. RT-PCR analysis revealed a heterogeneous expression pattern of MDM-2 mRNA in AML samples of different FAB classification. An increased level of MDM-2 mRNA expression was observed in 17 of 38 AML patients when compared to normal controls. No structural changes in a 488 bp region extending from nucleotide 890 to 1378 of the MDM-2 cDNA were detected using RT-SSCP and sequence analysis. In addition, heterogeneous expression of p53 transcripts was found with the highest p53 mRNA levels in AML M4 and M5. Interestingly, there seems to be a correlation between the relative ratios of p53 and MDM-2 mRNA levels in AML M4 and M5: in 15 of 23 cases high p53 mRNA expression was directly associated with high levels of MDM-2 transcripts. An exclusively intranuclear p53 immunostaining pattern was found in 10 of 16 (58%) AML FAB M4 and M5, whereas the remaining AML samples tested were negative for p53 (0/10). Using RT-SSCP analysis and direct sequencing of the RT-PCR amplification products of p53 exon 5-8, we observed that only 1 of 38 AML patients showed a point mutation in the p53 gene. This missense mutation occurred in the evolutionary highly conserved region of p53 at codon 255 (Ile to Phe). These data indicated that structural alterations of the p53 gene do not play an important role in the initiation and progression of AML. However, abrogation of p53 tumor suppressor function due to MDM-2 overexpression may be an alternative molecular mechanism by which a subset of AMLs may escape from p53-regulated growth control.

Acute Disease↗

Impact of preleukapheresis cell counts on collection results and correlation of progenitor-cell dose with engraftment after high-dose chemotherapy in patients with germ cell cancer.

PURPOSE: To identify predictive factors for a good leukapheresis yield and to determine peripheral-blood progenitor cell (PBPC) dose requirements for rapid hematopoietic engraftment. PATIENTS AND METHODS: Seventy-one patients with germ cell cancer (GCC) underwent PBPC harvest for autologous transplantation following high-dose therapy. Aphereses were performed after chemotherapy during granulocyte colony-stimulating factor (G-CSF) administration. RESULTS: A median of two aphereses (range, two to five) resulted in 4.6 x 10(8) mononuclear cells (MNC)/kg, 15.7 x 10(4) colony-stimulating units granulocyte-macrophage (CFU-GM)/kg, and 6.0 x 10(6) CD34+ cells/kg. Peripheral blood MNC count correlated significantly with number of harvested CD34+ cells per kilogram (r = .49; P < .0001) and with CFU-GM count per kilogram (r = .35; P < .002). Circulating CD34+ cells from peripheral blood gave the best correlations to collected CD34+ cells per kilogram (r = .92; P < .0001), as well as to harvested CFU-GM per kilogram (r = .48; P < .0001). A preleukapheresis number of CD34+ cells greater than 4 x 10(4)/mL was highly predictive for a PBPC collection yield that contained more than 2.5 x 10(6) CD34+ cells/kg harvested by a single leukapheresis. After autologous transplantation, 41 patients were assessable for hematopoietic engraftment. They engrafted in a median time of 9 days (range, 7 to 18) to a WBC count greater than 1.0 x 10(9)/L, 10 days (range, 7 to 18) to an absolute neutrophil count (ANC) greater than 0.5 x 10(9)/L, and 11 days (range, 7 to 62) to a platelet (PLT) count greater than 20 x 10(9)/L. Good correlations were seen between reinfused CD34+ cell count and recovery of WBC count, ANC, and PLT count, with r values of .65 (P < .001), .65 (P < .001), and .45 (P < .03), respectively. Patients reinfused with a PBPC dose greater than 2.5 x 10(6) CD34+ cells/kg recovered hematopoiesis in a significantly shorter time than patients who received less than 2.5 x 10(6) CD34+ cells/kg. CONCLUSION: Rapid hematopoietic engraftment can be achieved by a PBPC dose of greater than 2.5 x 10(6) CD34+ cells/kg. When circulating preleukapheresis CD34+ cell counts are greater than 4 x 10(4)/mL, a PBPC autograft that contains more than 2.5 x 10(6) CD34+ cells/kg can be collected by a single leukapheresis.

Adult↗

P53 and induction of apoptosis as a target for anticancer therapy.

p53 is the most frequently mutated gone in human cancer cells. Its wild-type gone encodes for a protein with pivotal functions: (i) interaction with key players in the cell cycle leading to cell cycle arrest; (ii) induction of programmed call death, or apoptosis. P53 may be seen as another member of the family of proteins involved in resistance to anticancer therapy, since mutations/deletions involving the p53 gene lead frequently to resistance of radiation/cytotoxic drug treatment. Consequently, patients with p53-mutated tumors may harbor a worse prognosis. On the other hand, reintroducing wild-type P53 may lead to an adequate function of the cellular cell cycle and/or apoptosis program, thus enabling efficient anti-cancer therapy even in the presence of mutated P53. Two options are being discussed: (i) gene therapy approaches; (ii) modulating mutated P53 with yet unknown molecules.

Animals↗

Preliminary results of stem cell mobilization in chronic myeloid leukemia with a moderate intensity chemotherapy regimen and G-CSF or G-CSF plus IL-3.

Mobilization of Philadelphia chromosome (Ph) negative peripheral blood stem cells has been reported subsequent to intensive chemotherapy. We asked whether peripheral blood stem cells can be harvested subsequent to a less toxic chemotherapy regimen. Patients were treated with idarubicin 12 mg/m2 on day 1 and 2 and ara-C 100 mg/m2 days 1-5 and 5 or 10 micrograms/m2 G-CSF. In case of insufficient yield chemotherapy was repeated using IL-3 and G-CSF for mobilization of stem cells. Fourteen patients received 18 cycles of chemotherapy. The majority of patients were in late chronic phase and treated after secondary (interferon-alpha) IFN-alpha resistance. sufficient numbers of peripheral blood stem cells were harvested in 11 out of 14 patients. Although mixed Ph positive/Ph negative leukaphereses were harvested in the majority of patients, in no case were sufficient numbers of purely Ph negative progenitor cells for transplantation obtained. No toxic deaths were observed during the aplasia and the toxicity was acceptable. These preliminary results demonstrate that this procedure can be safely applied in patients with chronic phase CML and allows the harvesting of sufficient numbers of peripheral blood stem cells. The efficacy of this regimen for the mobilization of Ph negative cells should be further explored in patients at an earlier stage of the disease.

Adult↗

Human herpesvirus type 7 in blood donors: detection by the polymerase chain reaction.

In order to evaluate the prevalence of human herpesvirus type 7 (HHV-7) in adult blood donors oral lavage fluid, buffy coat, and urine samples from 112 persons were examined by the polymerase chain reaction (PCR) at one time point. In addition, 11 donors were studied longitudinally over 11 weeks. When the results of the initial and the longitudinal study were combined HHV-7 DNA was found in samples from 109 of 112 (97.3%) adult blood donors. On the basis of different sensitivity levels of the first and the nested PCR differences were detected in the viral DNA load in the samples. It was found that lavage fluid regularly carried significantly higher DNA concentrations than buffy coat. Out of 112 donors, 102 (91.1%) and 8 (7.1%) were positive in the first, less sensitive PCR in lavage fluid and buffy coat, respectively (P < .0001). After nested PCR, 107 (95.5%) and 74 (66.1%) were positive in lavage fluid and buffy coat, respectively (P < .0001). Urine samples were found positive only sporadically. The longitudinal study showed that the oral lavage fluid of most of the donors consistently carried HHV-7 over up to 53 weeks, whereas buffy coat samples were positive less often. In conclusion, HHV-7 is found frequently in adult blood donors in the oral lavage fluid and buffy coat, which are, therefore, potential sources of HHV-7 transmission.

Adult↗

Autografting with blood progenitor cells: predictive value of preapheresis blood cell counts on progenitor cell harvest and correlation of the reinfused cell dose with hematopoietic reconstitution.

One hundred and nine patients suffering from various malignancies underwent 285 apheresis procedures for PBPC collection. A median of two leukaphereses (range: 2-5) resulted in median numbers of 4.6 x 10(8) MNC/kg, 14.1 x 10(4) CFU-GM/kg, and 6.0 x 10(6) CD34+ cells/kg. Preleukapheresis peripheral blood CD34+ cells correlated significantly with collected CD34+ cells/kg (r = 0.94; p < 0.0001) and with CFU-GM/kg (r = 0.52; p < 0.0001). A value > 4 x 10(4) CD34+ cells/ml was highly predictive for a collection yield > 2.5 x 10(6) CD34+ cells/kg harvested by a single leukapheresis. Sixty patients were evaluated for hematologic reconstitution and engrafted in a median time of 10 days for WBC > 1.0 x 10(9)/l (range: 7-21 days), 10 days for ANC > 0.5 x 10(9)/l (7-20) and 11 days for PLT > 20 x 10(9)/l (7-62). Reinfused CD34+ cells/kg correlated significantly with hematologic engraftment (r = 0.44-0.52 and p < 0.006-0.001) as well as CFU-GM/kg (r = 0.36-0.44 and p < 0.007-0.001). A progenitor cell dose > 2.5 x 10(6) CD34+ cells/kg or > 8.0 x 10(4) CFU-GM/kg led to a significantly faster recovery for WBC, ANC, and PLT when compared with patients receiving < 2.5 x 10(6) CD34+ cells/kg or < 8.0 x 10(4) CFU-GM/kg. We conclude that rapid hematopoietic engraftment after high-dose therapy and PBPC reinfusion correlates well with a progenitor cell dose > 2.5 x 10(6) CD34+ cells/kg or > 8.0 x 10(4) CFU-GM/kg, and that above a preleukapheresis threshold of 4 x 10(4) CD34+ cells/ml a PBPC autograft containing > 2.5 x 10(6) CD34+ cells/kg can be collected by a single leukapheresis. We suggest that patients recovering from myelosuppression should be monitored for CD34+ cells in serial blood samples to determine the course of circulating hematopoietic progenitor cells. This issue will help to define the optimal time point to start apheresis and to predict a PBPC autograft harvested by a single leukapheresis, which will lead to rapid and stable hematopoietic reconstitution following transplantation.

Adolescent↗

Tumorous manifestation of hairy cell leukemia after long-term treatment with interferon alpha.

Tumorous-manifestation of hairy cell leukemia in a patient treated with IFN alpha for 7 years is described. After this time, while the patient still was in hematological remission, a tumorous involvement of the lung by hairy cells developed and was successfully treated by surgery. No differences in the phenotype of hairy cells in the lung tumor, in the bone marrow, or in the blood could be detected.

Bone Marrow↗

A novel HLA-DR13 allele (DRB1*1314) identified by single-strand conformation polymorphism analysis and confirmed by direct sequencing.

A novel variant of the HLA-DR13 group is described. The new allele was found in a DR10, 13 heterozygous patient of Turkish origin, two HLA genotypically identical children of the patient typed as DR11,13, and one child typed as DR13,13. DR13 subtyping of the patient was initially performed by SSCP analysis of PCR-amplified DNA, using the 11th OHWS primers DRBAMP-3 and DRBAMP-B. Due to an unusual SSCP banding pattern, the PCR product was subjected to solid-phase sequencing. The sequence of the new allele, DRB1*1314, is different from that of DRB1*1307 by a single nucleotide substitution in codon 47, with T replacing consensus A. This results in a single amino acid change of tryptophan to phenylalanine in the first domain of the DR beta chain.

Anemia, Sickle Cell↗

Angioimmunoblastic lymphadenopathy (AILD)-type T-cell lymphoma: prognostic impact of clinical observations and laboratory findings at presentation. The Kiel Lymphoma Study Group.

BACKGROUND: In order to establish the clinico-pathological properties of angioimmunoblastic lymphadenopathy (AILD)-type T-cell lymphoma, we evaluated the type, incidence and prognostic significance of clinical and laboratory symptoms. PATIENTS AND METHODS: Sixty-two consecutive patients diagnosed at the Kiel lymph node registry participated in the study. The median patient age was 64 years (range 21-87 years) and the female to male ratio was 1:1.4. Ninety percent of the patients were in stage III and IV and B-symptoms were observed in 68%. At diagnosis patients presented with skin rash (49%), pruritus (32%), edema (38%), pleural effusion (37%), arthritis (18%) and ascites (23%). Furthermore, they exhibited autoimmune phenomena such as cold agglutinines, circulating immune complexes, a positive Coombs test, smooth muscle antibodies, rheumatoid factors, immune hemolysis, a paraprotein, antinuclear antibodies and cryoglobulins. RESULTS: In univariate analysis, survival was significantly related to age (p=0.032), stage (p=0.037), B symptoms (p=0.007), rash/pruritus (p=0.038), edema (p=0.030), ascites (p=0.013), number of clinical symptoms including B symptoms (p=0.004) and excluding B symptoms (p=0.017), lactate dehydrogenase (p=0.007) and hemoglobin (p=0.020). CONCLUSIONS: AILD type T-cell lymphoma characteristically differs from other non-Hodgkin's lymphomas in its clinical signs and laboratory symptoms.

Adult↗

Propagation of large numbers of cells of a human mixed-lineage T-lymphoid/myeloid.

Previously, a subset of T cells co-expressing the myeloid antigen CD33 has been described in patients with acute myelogenous leukaemia. However, normal lymphocytes have been viewed as not expressing the CD33 antigen. We have developed culture conditions which allow for the rapid expansion of CD3+CD33+ cells from patients with myeloid leukaemia as well as normal individuals. The protocol for cellular expansion includes the addition of interferon-gamma on day 0, interleukin-1, interleukin-2 and a monoclonal antibody against CD3 on day 1 to peripheral blood lymphocytes. Using this protocol, total cell number increased more than 600-fold within 16 d of culture. Cells could be kept in culture for more than 6 months. Cells of the CD3+CD33+ phenotype increased to 15.2 +/- 4.6% using this protocol after 16 d in culture. These cells have been characterized by flow cytometry and have been found to express the alpha, beta T-cell receptor, co-express the CD2, CD5, CD7 and HLA-DR antigens and did not express CD14 or CD15 antigens. Cells of the CD3+CD33+ phenotype were unable to lyse tumour cells as determined in a 51Cr release assay. In patients with chronic myeloid leukaemia. CD3+CD33+ cells seem to be negative for expression of bcr/abl transcript in contrast to CD33- cells. Our data suggest that CD3+CD33+ cells do exist in peripheral blood from normal individuals.

Antigens, CD↗