Biomedical subjects

H Kirchner

Publications and source records attributed to H Kirchner.

At least 163 records · Page 9Linked to original sources

PubMed1995

Immune responsiveness in orthopedic surgery patients after transfusion of autologous or allogeneic blood.

BACKGROUND: The proposed immunosuppressive effect of blood transfusion is not yet understood, and the clinical relevance is a controversial topic of discussion. STUDY DESIGN AND METHODS: The effect of blood transfusions on the capacity of the host's immunocompetent cells to react to mitogenic stimulation was evaluated. Patients undergoing hip replacement surgery received either allogeneic (n = 13) or autologous (n = 14) buffy coat-depleted red cells or plasma. Patients' blood samples taken before and on Days 1 and 5 after surgery were stimulated in a whole-blood assay. The release of interleukin 2, soluble interleukin 2 receptor, interleukin 6, tumor necrosis factor alpha, interferon alpha 2, and interferon gamma was assessed by enzyme-linked immunosorbent assay. In addition, the white cell counts and frequencies of the lymphocyte subsets CD4+, CD8+, and natural killer cells were analyzed. RESULTS: For both groups, decreased levels of interleukin 2 and interferon-gamma were detected postoperatively, whereas the values for soluble interleukin 2 receptor and tumor necrosis factor alpha showed no significant change. Interferon alpha 2 was decreased on Day 1, but returned to normal by Day 5. Interleukin 6 increased during the time of observation. There were no significant differences between the two groups in cytokine production and lymphocyte-subset analysis that could be attributed to the transfusion of allogeneic blood. CONCLUSION: The transfusion of buffy coat-depleted red cells showed no immediate suppressive effect on the immune function of the host's peripheral blood cells.

Adult↗

PubMed1995

In vivo distribution of integrins in renal cell carcinoma: integrin-phenotype alteration in different degrees of tumor differentiation and VLA-2 involvement in tumor metastasis.

We studied 23 renal cell carcinomas and two normal kidney tissues by immunohistochemistry using monoclonal antibodies against subunits of the VLA integrins (VLA-1 to VLA-6) and CD51. All integrins investigated in our study, except VLA-4 (ubiquitous negative), were distributed in different patterns in tumors assayed. We found a correlation between VLA-2 expression and site of tissue; primary tumor cells expressed no VLA-2 integrin, whereas tumor cells from metastatic tissues exhibited VLA-2 positivity (P < .009). Additionally, the expression of VLA-3 and VLA-5 correlated with tumor grading; both integrins were undetectable in G1 tumors but widely expressed in G2 and G3 tumors (VLA-3, p < .000; VLA-5, p < .005). Our results suggest that VLA-2 integrin is involved in metastasis of RCC and that poorly differentiated tumor cells have a different integrin phenotype when compared to normal or highly differentiated tumor cells.

Adult↗

PubMed1995

Failure to detect type 1 interferon production in human umbilical cord vein endothelial cells after viral exposure.

Cytokine production by endothelial cells is known to occur after the reception of signals such as interleukin-1 (IL-1) and tumor necrosis factor (TNF). In the present study, we demonstrate cytokine release and upregulation of adhesion molecule expression of human endothelial cells derived from umbilical cord veins in response to stimulants. The cells were exposed to the plant lectin phytohemagglutinin A (PHA), the viral inducers Newcastle disease virus (NDV) and Sendai virus, and the nucleic acid analog polyinosinic/polycytidylic acid (polyI:C). All stimulants induced expression of IL-1 beta and IL-6. The titers of these cytokines were comparable to those obtained in human leukocytes, whereas no TNF-alpha release was detectable. A further feature of activation was upregulation of intercellular adhesion molecule 1 (ICAM-1), which was analyzed after contact with these stimulants. These experiments revealed an increased expression of ICAM-1 in response to all stimulants tested. A major part of our studies was devoted to the ability of endothelial cells to produce interferons as an important function of a number of cell types in response to viral infections. To ensure stimulation of the cells, the inducers NDV, Sendai virus, and polyI:C were analyzed. Expression of interferon (IFN) was not detected, although viral inducers mediated the release of IL-1 beta and IL-6, suggesting that endothelial cells are quite responsive to these stimulants. In conclusion, these findings show that the ability of endothelial cells to secrete cytokines is not restricted to mediators of the immune system, such as IL-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Cells, Cultured↗

PubMed1995

Antiproliferative and recovery effects during treatment of breast and ovarian carcinoma cell cultures with interferon-gamma.

We studied the antiproliferative effects of human interferon-gamma (IFN-gamma) on cell lines derived from human carcinomas (three breast, two ovarian, and one renal) and recovery from these effects when IFN-gamma was removed after 6 or 72 h. IFN-gamma led to a dose-dependent and time-dependent cytostatic inhibition of all six tumor cell lines; the renal carcinoma cells were by far the most sensitive, and with these, cytotoxic effects were also seen. The 50% inhibitory dose (ID50) for each cell line was different and remarkably constant over many months. When cells were exposed to IFN-gamma for only 9 or 72 h, those from three lines recovered completely from the growth inhibitory effects, but from three only partially. When cultured for several weeks in the presence of 1600 U/ml of IFN-gamma, two lines developed increased resistance to IFN-gamma, one became much less sensitive, and two showed no changes in sensitivity. We saw no correlations between these changes during continuous exposure to IFN-gamma and the antiproliferative ID50 for each cell or whether the cells recovered completely from the inhibitory effects of IFN-gamma after short-term exposure. Nevertheless, cells with a population doubling time of less than 48 h had low to moderate sensitivity to IFN-gamma and seemed to recover more completely than those doubling in more than 61 h. Our results indicate great individual variation in the in vitro sensitivity of carcinoma cells to the antiproliferative effects of IFN-gamma.

Amino Acid Sequence↗

PubMed1995

Divergent effects of zinc on different bacterial pathogenic agents.

Zinc is essential for immunologic function; therefore, it has been postulated that elevated serum levels of zinc might lead to improved immune responses. However, it is not known whether or how serum zinc levels contribute to a clinically relevant mechanism of immunologic activation. In our studies with human peripheral blood mononuclear cells and whole blood, the zinc level selectively enhanced the biologic activity of endotoxin. The combination of nonstimulatory doses of lipopolysaccharide (LPS) and nonstimulatory concentrations of zinc led to the secretion of large amounts of interleukin (IL)-1 beta. In contrast, zinc levels specifically down-regulated monocyte activation caused by some superantigens, staphylococcal enterotoxin A and E and Mycoplasma arthritidis--derived superantigen, but not toxic shock syndrome toxin-1. This demonstrates that zinc levels control IL-1 beta secretion after both LPS and superantigen challenge within a clinically relevant range of concentrations. Our data suggest that the indications and contraindications for clinical zinc supplementation should be reconsidered.

Drug Synergism↗

PubMed1995

Cytokine production and serum proteins in depression.

One, as yet unemployed, approach to investigating immunology in depression is the assessment of the cytokine production by leucocytes, which would allow the determination of immune response under standardized conditions. Thus we measured the production of mitogen-induced cytokines (IL-1 beta, IL-2, IL-6, IL-10, interferon-gamma) and sIL-2R in a whole blood assay, and serum protein levels such as C-reactive protein (CRP), haptoglobin (Hp) and alpha 2-macroglobulin (alpha 2 M) in a longitudinal 6-week study in an attempt to assess leucocyte function during and after acute clinical stage of depression in 39 patients. Shortly after admission to hospital we found higher levels of all measured cytokines in the patients. Serum protein levels were significantly higher in the patients than in controls, and decreased over the study period. Whereas slightly elevated monokine levels in patients tended to reach control values, lymphokines showed a significant decrease over the 6 weeks as compared to baseline. These results suggest that the increase in immune activity seen at the beginning of the study may be followed by a suppressed cell-mediated immune function.

Acute-Phase Proteins↗

PubMed1995

Determination of the number of Epstein-Barr virus genomes in whole blood and red cell concentrates.

The risk of Epstein-Barr virus (EBV) infection after blood transfusion has been controversially discussed. Little is known about EBV transmission via buffy-coat-depleted red cell concentrates (RCC). In this study, we determined the number of EBV genomes in RCC of EBV-seropositive donors in comparison to whole blood. RCC were prepared from whole blood donations by using the 'top and bottom system'. Leucocyte content was significantly reduced in RCC in comparison to whole blood (0.47 x 10(9) vs. 2.3 x 10(9) per unit; P < 0.001). As B cells are expected to harbour EBV genomes, we analysed the number of B lymphocytes in both types of blood products. There was a significant reduction of B cell content from a median value of 90 x 10(6) in whole blood to 0.2 x 10(6) in RCCs (P < 0.001). The number of EBV genomes was estimated at a median value of seven from 10(6) B cells in the peripheral blood of healthy, EBV-seropositive blood donors by means of a polymerase chain reaction (PCR) assay. By calculation, one unit of RCC may contain an average of one to two EBV genomes, in contrast to a whole blood unit, which is likely to harbour an average of 600 to 700 EBV genomes. It is concluded that the use of leucocyte depletion systems significantly reduces the number of EBV genomes in erythrocyte concentrates. Thus, leucocyte reduced blood products appear to minimize the risk of EBV infection.

B-Lymphocytes↗

PubMed1995

Low resolution DNA typing of the HLA-B5 cross-reactive group by nested PCR-SSP.

We have established a DNA typing system for the HLA-B5 serologically cross-reactive group (CREG) by means of a two-step PCR amplification with nested sequence-specific primers (nPCR-SSP). The present study provides a low resolution definition of the HLA-B5 CREG, i.e. identifying polymorphism equivalent to serology. Two different primer combinations allow group-specific amplification of all HLA-B5 CREG alleles and other related HLA class I alleles from genomic DNA. The amplified DNA is subjected to a second amplification step using eleven nested primer pairs. This assay permits the detection of the HLA-B5 CREG specificities B35, B51, B52, B53, and B7801 in all homozygous and heterozygous combinations. Sensitivity and specificity as judged by a blind quality control study investigating a reference panel (n = 50) is 100%. Extension of this approach should allow rapid DNA typing of all serologically defined HLA-B specificities by nPCR-SSP.

Alleles↗

PubMed1995

Cytokines in platelet concentrates prepared from pooled buffy coats.

Platelet concentrates (PC) prepared from pooled buffy coat (BC-PC) contain a variable number of leukocytes from different donors. We questioned whether storage of BC-PC can lead to a lymphocyte activation in the sense of a mixed lymphocyte reaction. BC-PC were prepared from four ABO-identical buffy coats and we undertook leukocyte analyses and measurement of different cytokines on days 1, 3 and 5 of PC storage (n = 72). Cytokine content was also determined in freshly prepared plasma (n = 48) and PC prepared by thrombapheresis (SD-PC) (n = 12). As control, we studied lymphoproliferation of pooled peripheral blood mononuclear cells from four individuals in 10 mixed lymphocyte cultures (MLCs) under optimal conditions. In the BC-PC, whole blood count and lymphocyte analysis showed a mean leukocyte contamination of 64 +/- 28 x 10(6) per unit with a proportion of lymphocytes of 66.7 +/- 13%. In the MLC, levels of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) were increased on day 3 and 5 of storage (p < 0.001). In a proportion of BC-PC, tumor necrosis factor-alpha (72.2%) and IL-2 (43.1%) were detectable immediately after preparation, whereas IFN-gamma (4.2%), interleukin-1 beta (4.2%) and interleukin-8 (11.1%) were only found in some BC-PC. In all cases, initial values of cytokines did not increase during storage. Cytokine measurement in FFP and SD-PC showed similar results. The study demonstrates that cytokines are detectable in a variety of blood products immediately after preparation.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Platelets↗

PubMed1995

Impact of allergy screening for blood donors: relationship to nonhemolytic transfusion reactions.

There has been some discussion whether the atopic disposition of a blood donor is associated with a potentially higher incidence of hypersensitivity nonhemolytic transfusion reactions (NHTRs). Serum samples from patients who had suffered from NHTRs and samples from the platelet concentrates (PCs) responsible for the reactions were examined for total and specific IgE as diagnostic markers for allergic events. In addition, the allergy prevalence among 1,088 blood donors was determined to analyze the allergy prevalence among our blood donors. Our results indicate that in 90% of cases, allergic NHTRs were associated with specific IgE antibodies in the recipient's serum, indicating the allergic disposition of the patient. In contrast, specific IgE antibodies were detected in only 22% in the transfused PCs. However, among all investigated NHTRs, there was not a single case in which specific IgE antibodies were detected exclusively in the PC. The allergy prevalence among our blood donors was about 26%. In our opinion, the few cases in which the allergic disposition of blood donors in combination with the allergic disposition of the recipients was associated with NHTRs reflects the allergy prevalence among our blood donors in general (26%). On the basis of these findings, we conclude that allergy diagnosis for blood donors is only of minor value in the prevention and prediction of NHTRs, whereas allergy diagnosis for patients who require multiple PC transfusion might be helpful.

Antibody Specificity↗

PubMed1995

Cytokine production in a whole-blood assay after Epstein-Barr virus infection in vivo.

Epstein-Barr virus (EBV) has a marked tropism for cells of the immune system, and infection can result in profound immunomodulatory effects. In order to examine the role of cytokines during the acute phase of infectious mononucleosis, we studied the levels of different interleukins (ILs), interferons (IFNs), and the soluble IL-2 receptor (sIL-2R) in serum samples of 20 patients. We found elevated levels of IL-2, IL-6, sIL-2R, and IFN-gamma. Whereas the peak of IL-2 and IL-6 concentration occurred during the first week (P < 0.01), the largest amounts of sIL-2R were measured during the second week (P < 0.01). IFN-gamma levels were only enhanced during the first week. In addition, we investigated the ability to produce cytokines in response to mitogenic stimulation in a whole-blood assay of 11 patients compared with healthy blood donors. In the whole-blood assay of patients compared with controls after stimulation with lipopolysaccharide, we measured more than 10-fold elevated levels of tumor necrosis factor alpha (P < 0.01), 3-fold elevated levels of IL-1 beta (P < 0.01), and about 2-fold increased amounts of IL-6 (P < 0.01). A significant enhancement in sIL-2R and IFN-gamma concentration was found in the assay after stimulation with phytohemagglutinin after 24 h of incubation (P < 0.01). Collectively, our data seem to indicate that monocytes are strongly activated during infectious mononucleosis. Monocytes and monocyte-derived factors may play an important role in the pathogenesis of infectious mononucleosis and, together with T lymphocytes, may be partly responsible for clinical symptoms.

Adult↗

PubMed1995

Characteristics of viral protein expression by Epstein-Barr virus-infected B cells in peripheral blood of patients with infectious mononucleosis.

The frequency of Epstein-Barr virus (EBV) antigen-positive B cells in the peripheral blood of patients with infectious mononucleosis compared with that for latently EBV-infected individuals was examined by immunocytochemistry. B cells positive for Epstein-Barr nuclear antigen (EBNA) 1, EBNA2, and latent membrane protein were frequently found in all peripheral B lymphocyte preparations from 25 patients suffering for 3 to 28 days from infectious mononucleosis by using monoclonal antibodies and the alkaline phosphatase anti-alkaline technique. There was a significant decrease in the number of positive B cells during the course of disease. EBNA1-positive B cells were detected in 0.01 to 2.5% of total B cells (median, 0.8%), EBNA2-positive B cells were detected in 0.01 to 4.5% of total B cells (median, 0.9%), and latent membrane protein-positive B cells were detected in 0.01 to 1.8% of total B cells (median, 0.5%), depending on the duration of clinical signs. In contrast, we did not find any EBNA1- or EBNA2-positive B cells in 2 x 10(6) peripheral blood B lymphocytes of 10 latently EBV-infected individuals, whereas aliquots of the same cell preparations were EBV DNA positive by a PCR assay. Therefore, it appears to be possible to detect infectious mononucleosis by immunocytochemical determination of latent EBV products, which might be of relevance for the diagnosis of EBV reactivations in immunosuppressed patients.

Adolescent↗

PubMed1995

Multiinstitutional home-therapy trial of recombinant human interleukin-2 and interferon alfa-2 in progressive metastatic renal cell carcinoma.

PURPOSE: In a phase II multiinstitutional outpatient trial, patients with progressive metastatic renal cell carcinoma were treated with a combination of subcutaneous (SC) recombinant interleukin-2 (rIL-2) and recombinant interferon alfa-2 (rIFN alpha 2). PATIENTS AND METHODS: One hundred fifty-two patients with metastatic renal cell carcinoma were treated. Treatment courses consisted of SC rIL-2 at 20 x 10(6) IU/m2 three times per week in weeks 1 and 4, and at 5 x 10(6) IU/m2 three times per week in weeks 2, 3, 5, and 6. Additionally, patients received SC rIFN alpha 2 6 x 10(6) U/m2 once per week in weeks 1 and 4, and three times per week in weeks 2, 3, 5, and 6. RESULTS: There were nine (6%) complete responses (CRs) and 29 (19%) partial responses (PRs), for an overall response rate of 25% (95% confidence interval, 19% to 32%). The median duration of responses for CRs and PRs was 16+ and 9 months, respectively. Additionally, 55 patients (36%) had stable disease (SD). Fifty-nine patients (39%) had continued disease progression (PD) despite treatment, or went off study after less than 4 weeks of therapy. The majority of patients treated experienced fever, chills, malaise, nausea, vomiting, and anorexia, side effects that were mostly limited to World Health Organization (WHO) grade 1 and 2. However, one patient developed grade 4 CNS toxicity with extended somnolence. On cessation of therapy, the neurologic symptoms in this patient were fully reversible, with no neurologic deficiency. CONCLUSION: In summary, this multiinstitutional home-therapy setting of SC rIL-2 and SC rIFN alpha 2 in patients with progressive metastatic renal cell carcinoma demonstrated drastically reduced systemic toxicity, while it confirmed the therapeutic efficacy of the low-dose SC immunotherapy combination schedule.

Adult↗

PubMed1995

Subclass typing of IgG paraproteins by immunofixation electrophoresis.

We present a simple method for subclass typing of IgG paraproteins, with which we have demonstrated a large number of paraproteins that were undetected by conventional immunofixation techniques. The types and distribution of IgG subclass paraproteins were analyzed in 92 human sera in which IgG paraproteins had been demonstrated. The IgG subclass paraproteins were separated by agarose gel electrophoresis rapidly and simply and then typed with the use of sheep anti-human monospecific IgG1-IgG4 antibodies. In 24 of the sera analyzed, IgG subclass typing revealed 25 additional monoclonal bands that were not detected by conventional immunofixation electrophoresis with anti-IgG antisera. Most of these belonged to a different subclass type. The overall subclass frequencies were 68% IgG1, 13% IgG2, 16% IgG3, and 3% IgG4. The distribution of paraprotein subclasses, however, was different in monoclonal gammopathies of undetermined significance in which more IgG3 was shown, whereas in non-Hodgkin lymphomas the number of IgG2 paraproteins was greater than expected; this finding may have diagnostic and prognostic significance.

Antibodies, Monoclonal↗

PubMed1995

[Intestinal vasculitis and glomerulonephritis in hepatitis C- associated cryoglobulinemia].

In a 53-year-old female patient with recurrent, sometimes bloody diarrhea, the long standing diagnosis of an ANA-negative lupus erythematosus with membranoproliferative glomerulonephritis, leucocytoclastic vasculitis and chronic hepatitis was ruled out and the diagnosis of a hepatitis C associated cryoglobulinaemia was established. The origin of the diarrhea was due to intestinal vasculitis as a result of cold food or beverages.

Cryoglobulinemia↗

PubMed1995

Zinc regulates cytokine induction by superantigens and lipopolysaccharide.

Zinc is known to be greatly involved in the regulation of immune functions. Pharmacological zinc supplementation, leading to serum zinc concentrations of more than 0.025 mM, has often been suggested to improve immune responses. However, the exact influence of elevated zinc level on immune functions has not yet been investigated. We found that zinc level selectively enhances cytokine induction by lipopolysaccharide (LPS) in a concentration-dependent fashion: as little as 0.0125 mM supplemental zinc led to nearly 50% elevated interleukin-1 beta (IL-1 beta) levels both in polymorphonuclear cells (PBMC) and whole-blood cultures. The secretion of interferon-gamma (IFN-gamma) could be increased more than 10-fold by 0.1 mM zinc. This could not be observed during stimulation with phytohaemagglutin (PHA). In contrast, zinc levels concentration-dependently down-regulated monocyte activation caused by the superantigens, staphylococcal enterotoxins A and E (SEA, SEE, more than 90% down-regulation by 0.1 mM zinc), the Mycoplasma arthritidis-derived superantigen (MAS), but not toxic shock syndrome toxin-1 (TSST-1), while T-cell response remained unaffected. This was not the result of chemical degradation of the superantigens. We assume that zinc concentration regulates interactions between SEA, SEE and MAS, but not TSST-1 and their major histocompatibility complex (MHC) class II-binding sites. Our data demonstrate that zinc levels control the secretion of IFN-gamma and monokines after both LPS and superantigen challenge within a clinically relevant range of concentrations. This reveals new perspectives and indications for zinc supplementation and also indicates potential risks of therapeutic application of zinc.

Bacterial Toxins↗

PubMed1995

Lymphocyte-conditioned medium in combination with interleukin-2 effectively induces antitumour autoimmunity by adoptive transfer of short activated killer (SHAK) cells.

In this study, effective antitumour immunity was transferred by autologous short activated killer (SHAK) cells induced over four hours with lymphocyte conditioned medium (LCM) and recombinant interleukin-2 (rIL-2). Among eight patients with progressive metastatic renal cell carcinoma refractory to standard therapy, there were six objective tumour responses to SHAKs. Progression-free survival ranged from 0 to 8+ months, and overall survival ranged from 2 to 14+ months, with a median of 9+ months. Systemic toxicity of SHAKs was limited to flulike symptoms. Patient SHAKs provided a tumour-specific immunity, both cellular and humoral (expression and secretion of secondary cytokines, including IL-2, GM-CSF, INF-gamma and TNF-alpha), far superior to rIL-2 activated killer cells.

Adoptive Transfer↗

PubMed1994

Cytokine interactions in human mixed lymphocyte culture.

Human PBMC of healthy blood donors were used to investigate the interaction of cytokines in human MLC. Two-way MLC was performed because irradiation did not influence the cytokine release. We found different kinetic patterns for IL-2, IFN-gamma, and sIL-2R. Production of IFN-gamma was dependent on IL-2 release because anti-IL-2 addition resulted in more than 90% reduced IFN-gamma levels. Treatment with rIL-2 altered IFN-gamma kinetics, but not the total amount of IFN-gamma. Addition of anti-IFN-gamma led to decreased production of IL-2 and sIL-2R. A down-regulation of IL-2 and sIL-2R could also be observed after treatment with rIFN-gamma. No production of IL-4 and IL-10 was detected in MLC (detection limit 5 pg/ml). This could not be explained by IFN-gamma antagonism because IL-4 and IL-10 were not detectable even after addition of anti-IFN-gamma. Testing the TH1-TH2 cell antagonism, the addition of rIL-4 and rIL-10 resulted in IFN-gamma suppression depending on the timing of exposition. Treatment with rIL-10 inhibited IL-2 and sIL-2R release. We found no production of IL-1 alpha and IL-1 beta in MLC, whereas IL-6 and TNF-alpha release could be detected. Surprisingly, release of IL-6 and TNF-alpha could be blocked completely by addition of anti-IFN-gamma. This suggests that the release of IL-6 and TNF-alpha in MLC is dependent on IFN-gamma produced by T cells. In summary, TH1 cytokines play a central role in MLC regulation, whereas TH2 cytokines appear to be of little importance.

Cytokines↗