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H Kirchner

Publications and source records attributed to H Kirchner.

503 records · Page 28Linked to original sources
PubMedDate not supplied

Antiviral effects of recombinant tumour necrosis factor in vitro.

Tumour necrosis factor (TNF) was first described as a factor in the serum of mice injected with tubercle bacilli (BCG) and several days later with lipopolysaccharide (LPS). The gene encoding TNF has recently been cloned and pure recombinant human TNF is now available. TNF is known for its in vivo antitumour effect and in vitro cytotoxicity on certain transformed cell lines. Similarities in amino acid sequence and biological activity to lymphotoxin and cachectin have been reported, and very recently a growth-factor-like activity on diploid fibroblasts was observed. There is no similarity between these proteins and interferons (IFNs), which are also induced during in vivo induction of TNF. Here we describe the antiviral activity of pure recombinant human TNF in a typical in vitro antiviral assay which we discovered while investigating the possible role of TNF as an inducer of IFN.

2',5'-Oligoadenylate Synthetase↗
PubMedDate not supplied

Impact of various red cell concentrate preparation methods on the efficiency of prestorage white cell filtration and on red cells during storage for 42 days.

BACKGROUND: White cell (WBC) reduction prior to storage of red cell (RBC) concentrates may reduce the incidence of HLA alloimmunization and may improve the quality of stored RBCs. STUDY DESIGN AND METHODS: An integrated WBC-reduction filter system was tested after various RBC preparation procedures (from whole blood), and the influence of filtration on RBCs during storage for 42 days was investigated. Four additive system RBC preparation protocols were used. Units prepared from conventional triple blood bags were held for 4 to 6 hours at 22 degrees C, and then the RBCs were separated via a hard spin and filtration, performed immediately (Group 1) or after 18 hours' storage at 4 degrees C (Group 2). Units prepared from a top-and-bottom collection system were held at 22 degrees C for 4 to 6 or 22 to 24 hours; the centrifuged RBCs were filtered immediately after preparation (Groups 3 and 4, respectively, by holding time). WBC reduction and filtration time were analyzed. The impact of WBC filtration on pH, hemolysis rate, hemoglobin content, ATP, potassium glucose, and lactate was investigated weekly during storage for 42 days. RESULTS: Filtration reduced the mean WBC count by 3 to 4 log10, to 0.19 +/- 0.25 x 10(6), regardless of the RBC preparation method. Mean filtration times differed significantly between the groups and were longest for Group 1. Besides hemolysis and pH values, which were greater in all filtered units, no major differences were found in filtered and unfiltered RBCs during the storage interval. CONCLUSION: The efficiency of prestorage WBC filtration of RBCs was unaffected by the preparation procedure. However, the filtration time for RBCs freshly prepared in the conventional triple blood bag system without buffy-coat depletion was unacceptable. No major metabolic differences between filtered and unfiltered RBCs during 42 days of storage were found.

Blood Preservation↗
PubMedDate not supplied

Febrile and allergic transfusion reactions after the transfusion of white cell-poor platelet preparations.

BACKGROUND: Nonhemolytic transfusion reactions (NHTRs) frequently occur after platelet transfusions. White cell (WBC)-derived inflammatory cytokines can cause these reactions, but they are rarely found in WBC-poor platelet preparations. Transfusion reactions were investigated with regard to the residual WBC content in the stored platelet concentrate in two consecutive study periods. STUDY DESIGN AND METHODS: In the first study period, platelet concentrates were WBC-reduced by bedside filtration. In the second period, all platelet concentrates were filtered before storage. Recipients who experienced transfusion reactions were examined with regard to their main clinical symptoms during and after transfusion. In the supernatant of the involved platelet concentrates, concentrations of interleukin (IL)-1beta, IL-6, IL-8, tumor necrosis factor (TNF)alpha, macrophage inflammatory protein 1alpha, and RANTES were analyzed. RESULTS: The incidence of transfusion reactions remained steady when the transfusion regimen was changed from bedside filtration to prestorage WBC filtration (1.63% and 1.56%; p = 0.84). In both periods, NHTRs were predominantly of allergic origin. Inflammatory mediators IL-1beta, IL-6, IL-8, and TNFalpha were detectable in only a minority of platelet components involved in NHTRs. Platelet concentrates involved in allergic reactions contained high concentrations of RANTES (668 +/- 223 ng/mL). CONCLUSIONS: Prestorage WBC filtration did not reduce the incidence of these reactions, and inflammatory cytokines were of minor relevance. The proinflammatory platelet-derived chemokine RANTES, which accumulates even in WBC-reduced platelet concentrates, was associated with allergic transfusion reactions. Platelet-derived mediators may be a key to understanding NHTRs.

Antilymphocyte Serum↗
PubMedDate not supplied

Real-time polymerase chain reaction (RQ-PCR) for the monitoring of Epstein-Barr virus (EBV) load in peripheral blood mononuclear cells.

Measurement of Epstein-Barr virus (EBV) load is useful in peripheral blood for detecting primary and reactivated EBV-infections especially in immunosuppressed patients being at high risk for developing posttransplant lymphoproliferative disorder. For quantification of EBV DNA in peripheral blood of patients two real time polymerase chain reaction (RQ-PCR) assays were developed detecting sequences specific for the BAM HI-W and BAM HI-K region of EBV. In order to determine the optimal material of peripheral blood for RQ PCR analysis, DNA preparations of whole blood, peripheral blood mononuclear cells (PBMC) and B cells from 11 healthy, EBV-seropositive individuals were analysed in parallel and compared with regard to efficiency and sensitivity. While in whole blood preparations inhibitors of RQ PCR were detected influencing sensitivity, analysis of B cells being most sensitive is limited by being too labour intensive. In contrast, analysis of DNA preparations of PBMCs is sensitive enough to frequently detect EBV-specific sequences in all individuals tested and the preparation of PBMCs itself needs only a reasonable time. Thus, longitudinal monitoring of EBV load in peripheral blood of patients is possible by RQ-PCR, the optimal material for analysis being PBMCs.

B-Lymphocytes↗
PubMedDate not supplied

[Interferons--biologic principles and clinical uses].

Interferons are components of the nonspecific defense system. Their most prominent biological roles are the antiviral, the antiproliferative, and the immunoregulatory activities. However, their primary functions within the organism remains to be determined. Three types of IFNs have been described so far (IFN alpha, IFN beta, IFN gamma). They possess similar but not necessarily identical biological activity. Interferons resemble peptide hormones and growth factors in that they bind to receptors on the cell surface, exert their activity through a postulated "second messenger" and are effective at picomolar concentrations. Interferons have been used as therapeutic agents in viral and malignant diseases with encouraging results in some patients. However, in only few instances interferon may become the standard therapeutic regimen. Since novel therapeutic approaches for cancer and viral disease are urgently needed, additional clinical trials with interferons seem to be justified. These have become feasible because sufficient amounts of pure interferon are available by novel production techniques based on modern biotechnology.

Cell Division↗
PubMedDate not supplied

Feasibility of the adoptive transfusion of allogenic human leukocyte antigen-matched natural killer cells in patients with renal cell carcinoma.

Patients with metastasized renal cell carcinoma have a poor prognosis with conventional therapies. The feasibility and safety of donating purified natural killer (NK) cells without additional cytokines were evaluated. In contrast to all previous studies, the NK cells were derived from allogenic donors. The NK cell donors were HLA-C matched to enable NK cell inhibition via killer cell inhibitory receptors and HLA-C. This should obviate a graft-versus-host reaction against nonmalignant HLA-expressing tissues in the allogenic constellation. The average number of cells applied per transfusion was 1.02 +/- 0.265 x 10(9). The purity of the NK cells was 85% to 95%, and most of the contaminating cells were monocytes. Twenty-six transfusions given to 11 patients did not cause any minor or major adverse effects, with the exception of one episode of transient fever. One patient had an objective regression of his lung metastases that had been progressing continuously before. No cytotoxic HLA antibodies could be detected 3 weeks after the transfusions. The observed tolerance to this therapeutic regimen suggests the need for further studies with increased doses of cytokine-activated NK cells.

Adoptive Transfer↗
PubMedDate not supplied

Multidirectional interactions in an Mls-disparate response.

The murine T cell clone E11, isolated from a primary H-2k-histocompatible, one-way mixed lymphocyte culture of B10.BR anti-C3H/Tif spleen cells, has been used to analyse multidirectional interactions in Mls-disparate responses. Several events can be observed. There is proliferation of T cells upon stimulation by macrophages or B cells of Mls-disparate stimulator cells. In addition, one finds induction of differentiation of B cells of stimulator strains. E11 T cells inhibit spreading and differentiation of macrophages of stimulator strains and also prevent the production of a T cell growth-supporting mediator by Mls-disparate spleen cells. All these phenomena can be explained by Mlsa,d,e-specific induction of gamma-interferon (gamma-IFN) production in the responder B10.BR (Mlsb) E11 T cells. It is suggested that gamma-IFN, as a regulator of feedback mechanisms, plays an essential role in Mls-disparate cell interactions.

Animals↗
PubMedDate not supplied

Treatment of metastatic colorectal cancer patients with 5-fluorouracil in combination with recombinant subcutaneous human interleukin-2 and alpha-interferon.

We treated 14 patients with progressive metastatic colorectal cancer, using a combination of subcutaneous recombinant human interleukin-2 (4.8 x 10(6) IU/m2 three times daily on days 1 and 22, and twice daily on days 2 and 23, followed by 2.4 x 10(6) IU/m2 twice daily on days 3-5, 8-12, 24-26, and on 5 consecutive days per week, starting day 29), recombinant human interferon-alpha 2a (5.0 x 10(6) U/m2 thrice weekly), and 5-fluorouracil (750 mg/m2 i.v. bolus on days 15-19, and at weekly intervals thereafter, with a 1-week off-therapy interval every 4 weeks). Therapy was continued until disease progression occurred. Four (29%) and 8 (57%) evaluable patients achieved partial remission and stable disease, respectively; median response duration was 5.9 months. Toxicity of this regimen was moderate; the most common side effects were thrombocytopenia, leukopenia, nausea/vomiting, anorexia, malaise and fevers in all patients, along with diarrhea (63%) and mucositis (54%). Less than 10% of patients developed WHO grade IV toxicity; no toxic deaths occurred. Efficacy of this combination was not substantially different from alternative 5-fluorouracil-based regimens.

Adult↗
PubMedDate not supplied

Immunocytochemical detection of P-glycoprotein: initial expression correlates with survival in renal cell carcinoma patients.

We evaluated 28 patients with advanced renal cell carcinoma for the initial expression of P-glycoprotein (MDR1 gene product) employing immunocytochemistry. Tumor specimens were obtained upon primary tumor nephrectomy. In all patients, progression-free survival time following nephrectomy was evaluated and correlated statistically with the staining results. Progression-free survival of patients with no or very few (< 1%) P-glycoprotein-positive tumor cells (n = 8, median survival 27.0 months) was significantly extended (p < 0.04) as compared to patients with 1% or more P-glycoprotein-positive tumor cells (n = 20, median survival 4.0 months). Correlations with histopathological tumor characteristics were insignificant. These results suggest a potential role for P-glycoprotein as a biologic parameter predictive of tumor progression in renal cell carcinoma patients.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Platelet endothelial cell adhesion molecule-1 (PECAM-1): a potential prognostic marker involved in leukocyte infiltration of renal cell carcinoma.

We investigated immunohistochemically the leukocyte infiltrate [CD3, CD4, CD8, CD11a, CD11b, CD14, CD56, VLA-4 and platelet endothelial cell adhesion molecule-1 (PECAM-1)] and the endothelial expression of cell adhesion molecules (PECAM-1, VCAM-1, ICAM-1 and ICAM-2) in 23 renal cell carcinoma tumor tissues. Tumors with a moderate or high density of PECAM-1 positive endothelia showed a stronger infiltration with PECAM-1-positive leukocytes as compared to tumors with a low density of positive endothelia (p<0.0085). Additionally, overall survival of patients who presented with tumors exhibiting a moderate or high density of PECAM-1 endothelia alone or in combination with a PECAM-1-positive infiltrate was extended (median survival: 23.5 months) as compared to patients without these tumor characteristics (median survival: 6.5 months). These results suggest an involvement of PECAM-1 in the process of leukocyte migration and a potential role as a prognostic marker in renal cell carcinoma.

Adult↗
PubMedDate not supplied

In vivo and ex vivo antitumor activity in patients receiving low-dose subcutaneous recombinant interleukin-2.

Alterations in cell-mediated cytotoxicity levels were studied in patients receiving recombinant interleukin-2 (rIL-2) via subcutaneous injection. Fourteen outpatients, aged 36-68 years, with progressive metastatic malignancies, were treated with weekly escalated doses of rIL-2, starting at 1.8 IU/m2/day for 6 days a week, up to 14.4 IU/m2/day during the 4th week of therapy. Patients presenting with stable disease thereafter were started on maintenance therapy and received 10.8 IU/m2 once weekly for up to 12 weeks. Patient mononuclear cells were isolated from fresh peripheral blood at various times throughout the treatment. Cells were assayed prior to and after further in vitro stimulation by rIL-2 (600 IU/ml for 7 days). Natural killing (NK) activity was measured by cytolysis of K 562 target cells, and lymphokine-activated killing (LAK) was determined by cytotoxicity against Daudi targets, respectively, in four effector:target ratios (E:T), using a standard 2-hour europium3+ release assay. Spontaneous NK cell function (E:T = 25:1) of freshly isolated peripheral blood mononuclear cells (PBMC) was enhanced significantly after 28 days of therapy (27.8 vs. 9.1% on day 0). LAK activity also markedly increased during therapy (26.2 vs. 5.4% on day 0). Further in vitro culture of these PBMC in the presence of rIL-2 resulted in day 28 non-MHC-restricted cytolytic activity of 63.2% (40.3% on day 0) against K 562 targets, and 64.9% (39.6% on day 0) against Daudi targets. Activation of cytolytic function by rIL-2 appeared to be dose-dependent, as measurable lytic capability decreased throughout maintenance therapy, while neither sex nor tumor entity prior to therapy or clinical response were correlated with cytotoxicity levels. Taken together, our observations demonstrate that stimulation of the non-MHC-restricted pathway of cytolytic activation, as measured by lysis of target cells, arises in patients treated with rIL-2 doses 5- to 30-fold lower than used previously in intravenous protocols, connecting effective clinical response rates with acceptable tolerability.

Adult↗
PubMedDate not supplied

[Musculoskeletal manifestations in patients after bone marrow transplantation. Initial clinical rheumatologic observations].

From January 1986 through January 1989 69 adult patients received bone marrow transplants--20 with autologous, and 49 with allogeneic bone marrow. Ten patients after autologous and 33 patients after allogeneic transplantation (TX) could be examined for rheumatological complaints. None of the patients after autologous TX displayed rheumatological manifestations; 8/33 patients after allogeneic TX developed bone necrosis and they had to be treated for several months with high daily doses of prednisolon (mean: 55 mg/day). In 18/33 patients an oligoarthropathy of large joints could be observed after a significant reduction of prednisolon dosage over a period of 5 months. In addition 15/18 of these patients later developed a chronic g-v-h-disease. The TX arthropathy may be induced by cortico-steroid therapy (resp. reduction), but most important, it is a clinical sign for an imminent chronic g-v-h-disease.

Adult↗
PubMedDate not supplied

[Prostaglandin E2, interleukin 1 and gamma interferon production of mononuclear cells of patients with inflammatory and degenerative joint diseases].

Inflammatory joint diseases exhibit distinct pathohistological and immunological characteristics. The studies performed demonstrated that in comparison to normal controls peripheral blood mononuclear cells from patients with rheumatoid arthritis (RA) presented an increased percentage of monocytic cells. Peripheral blood mononuclear cells from patients with RA produced significantly increased amounts of prostaglandin E2 and significantly decreased amounts of interferon-gamma following mitogen stimulation with LPS or PWM respectively. The spontaneous production of interleukin 1 was found to be elevated. A significantly increased LPS induced production of prostaglandin E2 could also be observed in monocyte depleted rheumatoid peripheral cells and in peripheral cells of patients with osteoarthritis and HLAB27 associated joint diseases. Mononuclear cells from rheumatoid synovial tissue produced increased amounts of prostaglandin E2 and decreased amounts of interferon-gamma; the spontaneous prostaglandin E2 production was similar to the values obtained by mitogen stimulation which may originate from the distinct cellular composition of synovial tissue.

Adult↗
PubMedDate not supplied

Protection by polyI:polyC against infection with herpes simplex virus in mice pretreated with Corynebacterium parvum.

The effect of Corynebacterium parvum on the protection by polyinosinic-polycytidylic acid (polyI:polyC) against lethal infection with Herpes simplex virus type 1 (HSV) was studied in mice. Pretreatment with C. parvum resulted in prolonged survival times in all experiments. One third of the mice survived an infection with 100 LD50, whereas all mice died when treated with polyI:polyC alone. Increased protection was observed up to 6 weeks after pretreatment and only seen when both C. parvum and polyI:polyC were given at the same site of injection (intraperitoneally). Protection against HSV correlated with increased interferon (IFN) activities induced by polyI:polyC in the peritoneal cavity of C. parvum-pretreated mice. In these mice, natural killer cell activity of peritoneal exudate cells (PEC) was also augmented in response to polyI:polyC. Protection was markedly decreased by intraperitoneal injection of silica or of an antiserum against murine IFN. It appears that increased local levels of IFN presumably produced by macrophages in response to polyI:polyC in C. parvum-pretreated mice play the major role in the antiviral defence in our model and that activation of NK cells may be a secondary effect of IFN.

Adjuvants, Immunologic↗
PubMedDate not supplied

In vivo tumor necrosis factor-alpha as indicator of biologic and clinical response to low-dose SC recombinant interleukin 2.

The effect of low-dose human recombinant interleukin-2 (rIL-2) on the induction of secondary tumor necrosis factor-alpha (TNF-alpha) in vivo was studied in 16 patients with metastatic renal cell carcinoma. In all patients s.c. rIL-2 resulted in a significant increase in TNF-alpha serum levels within 4 to 8 hours, as determined by enzyme-linked immunosorbent assay (ELISA). TNF-alpha serum concentrations remained elevated up to 24 hours following single s.c. administration of rIL-2. Total secondary TNF-alpha release, as assessed by the area under the curve (AUC), appeared to be independent of dose distribution of rIL-2 (10 million IU rIL-2 q12 hours versus 20 million IU rIL-2 q24 hours). rIL-2 induced TNF-alpha release was significantly higher in patients who had received prior rIL-2 immunotherapy, while steroids resulted in a significant suppression of TNF-alpha release. Secondary TNF-alpha release was statistically associated with progression-free survival of renal cell carcinoma patients and may be a prognostic factor in patients receiving rIL-2.

Adult↗
PubMedDate not supplied

Cytokine expression in intestinal mucosal biopsies. In situ hybridisation of the mRNA for interleukin-1 beta, interleukin-6 and tumour necrosis factor-alpha in inflammatory bowel disease.

Etiology and pathogenesis of inflammatory bowel disease (IBD) remain obscure. There is substantial evidence that proinflammatory cytokines such as Interleukin-1 beta (IL-1 beta), Interleukin-6 (IL-6) and Tumour Necrosis Factor-alpha (TNF-alpha) exhibit a key role in the the inflammatory process. In situ hybridisation can depict individual cells producing cytokine mRNA. We performed hybridisation with antisense probes specific for IL-1 beta, IL-6 and TNF-alpha on sections of paraffine-embedded biopsies. Specimens obtained from three control persons and six cases of Crohn's disease (CD) were investigated. Only few positive cells were found in tissue sections of control persons, clusters of lamina propria cells or epithelial cells containing cytokine mRNA were not observed. Inflammatory bowel disease tissue contained large numbers of cells producing mRNA specific for the three proinflammatory cytokines assayed. IL-1 beta, IL-6 and TNF-alpha mRNA were predominantly detected corresponding to cells of the lamina propria. Single cells containing mRNA specific for IL-6 were also found among the epithelial lining of intestinal crypts. Epithelial cells containing IL-1 beta and IL-6 mRNA were found in specimens derived from one patient with Crohn's disease. Notably, large amounts of cells containing cytokine mRNA were not only found in inflamed, but also in macroscopically normal mucosa. In conclusion, using proinflammatory cytokines as a model, we established in situ hybridisation on sections of mucosal biopsies permitting further insight into immune activation at individual cell level.

Biopsy↗