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Biomedical subjects

B M von Blomberg

Publications and source records attributed to B M von Blomberg.

At least 19 recordsLinked to original sources
PubMed2001

Induction of tolerance and cross-tolerance to methacrylate contact sensitizers.

Induction of immunological tolerance to contact allergens might prevent undesired sensitization, in particular to occupational sensitizers, e.g., methacrylates (MA). Here, using a guinea pig model, we studied to which extent tolerance to one methacrylate might result in cross-tolerance to other congeners. Strong tolerance to the monomethacrylates hydroxy-ethyl MA (HEMA) and methyl MA, but not to the dimethacrylate ethylene-glycol MA (EGDMA) could be induced. The induced tolerance was stable, could not be broken by repeated sensitization attempts, and was mediated by specific suppressor cells, as demonstrated in T cell transfer experiments. In HEMA-tolerized animals, strong cross-tolerance to methacrylate congeners, including EGDMA, itself being nontolerogenic and showing the lowest cross-reactivity to HEMA, was found. Thus, oral application of contact allergens, to which skin contact cannot be avoided, e.g., in occupational settings, can induce broad cross-tolerance to related substances and might offer a promising preventive approach.

Allergens↗
PubMed2001

Circulating V(alpha24+) Vbeta11+ NKT cell numbers are decreased in a wide variety of diseases that are characterized by autoreactive tissue damage.

Natural killer T (NKT) cells have been implicated as playing an important role in regulating immune responses. Defects in the NKT cell population were reported in animal autoimmune disease models and in distinct human autoimmune diseases. Here, we report that circulating V(alpha24+) Vbeta11+ NKT cell numbers are decreased in a broad variety of disorders with (auto)immune-mediated pathology, affecting the skin, bowel, central nervous system, and joints, regardless of disease duration or activity. Remarkably, normal circulating V(alpha24+) Vbeta11+ NKT cell numbers were found in Graves disease and coeliac disease. Since earlier studies noted a rise in NKT cells in myasthenia gravis, the picture emerges in which a defective NKT cell population is associated with autoreactive tissue damage rather than with the propensity to develop autoimmune disease. The present data support the idea that therapies aiming at the in vivo expansion of regulatory NKT cells might help to control immune-mediated damage in autoimmune disease.

Antigens, CD1↗
PubMed2001

Ultrasonic energy vs monopolar electrosurgery in laparoscopic cholecystectomy: influence on the postoperative systemic immune response.

BACKGROUND: The influence of surgical operations on the systemic immune response is proportional to the degree of trauma. Ultrasonic surgery can dissect structures and divide vessels by the effect produced by vibrations in the tissues. It is believed to be less traumatic than the more commonly used monopolar electrosurgery. This randomized study compares the systemic immune response after laparoscopic cholecystectomy performed using either ultrasonic energy or monopolar electrosurgery. METHODS: Eighteen patients scheduled for elective laparoscopic cholecystectomy were randomly assigned to treatment using either a harmonic scalpel and clips or monopolar electrosurgery and clips. Postoperative inflammatory response was assessed via changes in the white blood cell count and levels of C-reactive protein. Postoperative immune function was assessed by measuring monocyte HLA-DR expression. RESULTS: Both the harmonic scalpel and the use of monopolar electrosurgery resulted in activation of the systemic immune response. No significant differences between the two groups were observed. CONCLUSION: The harmonic scalpel and monopolar electrosurgery are equally traumatic in terms of activation of the systemic immune response.

C-Reactive Protein↗
PubMed2001

Immune-stimulating effects of low-dose perioperative recombinant granulocyte-macrophage colony-stimulating factor in patients operated on for primary colorectal carcinoma.

BACKGROUND: Surgery induces a postoperative immunosuppression, thereby possibly facilitating the outgrowth of pre-existing occult metastases or the seeding of disseminated tumour cells in patients with primary colorectal carcinoma operated on with curative intent. The hypothesis that adjuvant therapy with perioperative recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) would minimize postoperative immunosuppression was investigated in this pilot study. METHODS: Patients were allocated randomly to receive daily subcutaneous injections with either saline (n = 8) or rhGM-CSF 2.8 microg per kg body-weight (n = 8) from 3 days before operation until 4 days afterwards. Phytohaemagglutinin (PHA) skin test reactivity, monocyte human leucocyte antigen (HLA) DR expression and the extent of the acute-phase response, by determination of white blood cell count and differentiation, plasma interleukin (IL) 6 levels and body temperature in the perioperative period, were examined. RESULTS: rhGM-CSF treatment minimized postoperative suppression in PHA skin test reactivity and increased the numbers of neutrophils and monocytes while enhancing the expression of HLA-DR in the postoperative period. Additionally, both postoperative plasma IL-6 levels and the incidence of fever tended to be higher in the rhGM-CSF group. CONCLUSION: In this pilot study, perioperative administration of low-dose rhGM-CSF stimulated certain immune functions that are normally depressed after operation. The implications for the antitumour responses directly after operation and the formation of liver metastases are currently under investigation.

Adjuvants, Immunologic↗
PubMed2000

Human natural killer T cells acquire a memory-activated phenotype before birth.

Natural killer T (NKT) cells have recently been shown to play an important role in the rejection of malignant tumors and in the regulation of autoimmune diseases. Potent antitumor effects of the marine sponge-derived NKT cell ligand KRN7000 were observed in mice. Therefore, the elucidation of the natural ligand of NKT cells, which is currently still unknown, might have important clinical consequences for the treatment of cancer and autoimmune diseases. Analysis of cord blood mononuclear cells from healthy term infants demonstrated that in sharp contrast with the vast majority of cord blood lymphocytes, human NKT cells have already acquired a memory-activated phenotype before birth. This observation indicates that NKT cells encounter a natural ligand during fetal life and that this ligand is unlikely to be of microbial origin.

Adult↗
PubMed2000

Synergistic effect of KRN7000 with interleukin-15, -7, and -2 on the expansion of human V alpha 24+V beta 11+ T cells in vitro.

KRN7000, (2S, 3S, 4R)-1-O-(alpha-D-galactopyranosyl)-2-(N-hexacosanoylamino)-1, 3, 4-octadecanetriol, has been shown to prevent tumor metastasis to the liver through the activation of natural killer (NK) T cells in mice. In this study, the proliferation of human NK T cells, which express an invariant T cell antigen receptor (TCR) consisting of a Valpha24 chain and a Vbeta11 chain, was investigated using KRN7000, interleukin (IL)-15, IL-7, and IL-2 in vitro. KRN7000 stimulated the expansion of Valpha24(+)Vbeta11(+) T cells derived from peripheral blood mononuclear cells in a dose-dependent fashion, with some fluctuation between donors. IL-15, IL-7, and IL-2 synergistically stimulated the expansion of Valpha24(+)Vbeta11(+) T cells when combined with KRN7000. Intracellular expression of interferon (IFN)-gamma and IL-4 in Valpha24(+)Vbeta11(+) T cells expanded in the presence of KRN7000 was identified using flow cytometry. Valpha24(+)Vbeta11(+) T cells, expanded in the presence of KRN7000, contained granzyme (Gr) B-positive granules and perforin-positive granules. The addition of IL-15 to the culture containing KRN7000 increased GrB expression in Valpha24(+)Vbeta11(+) T cells while IL-7 and IL-2 failed to do it. In conclusion, the antitumor effect of KRN7000 may depend, in part, on granule-mediated cell killing through the activation of NK T cells and IL-15 may potentiate this effect.

Adjuvants, Immunologic↗
PubMed2000

Accuracy and cost-effectiveness of a new strategy to screen for celiac disease in children with Down syndrome.

OBJECTIVES: To investigate the best approach to screen for celiac disease (CD) in patients with Down syndrome (DS). STUDY DESIGN: One hundred thirty-seven children with DS were followed up longitudinally. CD screening was offered in 1994, 1996, and 1999 by determination of serum immunoglobulin A-anti-endomysium antibodies (AEA). The HLA-DQA1*0501/DQB1*02 allelic combination known to be strongly positively associated with CD was typed. All IgA-AEA-positive children were given the opportunity to undergo a small bowel biopsy: if villous atrophy was found, the diagnosis of CD was established. RESULTS: CD was diagnosed in 11 (8%) children: 8 in 1994 and 3 in 1996. All of them carried the HLA-DQ alleles associated with CD. The presence of symptoms was not useful in discriminating which children could have CD. CONCLUSIONS: Screening once in a lifetime is not enough to detect CD in patients with DS. We propose a new, accurate, and cost-sparing 2-step strategy for screening, based on selection of the individuals with potential CD by HLA-DQ typing and on longitudinal serologic CD screening in this selected group.

Alleles↗
PubMed2000

In vivo effects of sex steroids on lymphocyte responsiveness and immunoglobulin levels in humans.

The female predominance in several autoimmune diseases suggests a role for sex steroid hormones in disease susceptibility. We therefore investigated to what extent sex hormones would influence immune responsiveness. We analyzed T helper type 1 (TH1) and type 2 cytokine patterns, chemokine receptor expression (n = 2 x 10), and Ig levels (n = 2 x 25) in transsexual men and women before and after 4 months of cross-sex hormone administration. Antithyroperoxidase levels were compared between 186 transsexual males (treated >5 yr with estrogens) and 186 male controls. In men, estrogens plus antiandrogens increased free cortisol levels in 24-h urine samples, decreased natural killer cell numbers, and slightly inhibited the mitogen-induced interferon-gamma/interleukin-4 ratio, but up-regulated the expression of TH1-associated chemokine receptors, CCR1, CXCR3, and CCR5. Conversely, in women, androgens slightly decreased free cortisol levels in 24-h urine samples and enhanced the mitogen-induced interferon-gamma/interleukin-4 ratio and tumor necrosis factor-alpha production. At the single cell level no TH 1/TH2 shifts were found. Remarkably, up-regulation of TH1 cytokines was accompanied by down-regulation of CCR1, CXCR3, and CCR5 expression. Neither CD4+ lymphocyte numbers nor IgG, IgM, and antithyroperoxidase levels, although higher in women then in men, were affected by cross-sex hormonal treatment. These results demonstrate that the capacity to develop a TH1 phenotype of peripheral blood lymphocytes is stimulated by androgens and is slightly inhibited by estrogens. These changes may be direct or indirect through the effects on other hormones.

Adolescent↗
PubMed1999

High prevalence of hemostatic abnormalities in women with a history of severe preeclampsia.

OBJECTIVE: In patients with a history of severe preeclampsia, an increased frequency of hemostatic abnormalities has recently been suggested in small studies without control groups. Our purpose was to investigate the prevalence of such abnormalities in a large patient group with a history of severe hypertensive disorder in pregnancy, in comparison with an appropriate control group. STUDY DESIGN: A total of 345 patients with a history of severe preeclampsia were investigated at a minimum of 10 weeks post partum for the presence of activated protein C resistance, the associated factor V mutation, hyperhomocysteinemia and anticardiolipin antibodies. The control group consisted of 67 healthy women with a history of uncomplicated pregnancies only. Blood was obtained during the second half of a normal menstrual cycle, and none of the patients or control subjects used oral contraceptives. RESULTS: Of all patients, 11.3% had activated protein C resistance (control subjects 1.5%, P =.025). Only half of these patients had the factor V mutation. Hyperhomocysteinemia was present in 12.1% of all patients, in comparison with 4.5% in the control group (P =.115). Anticardiolipin antibodies were observed in 20.9% of the patients, whereas these antibodies were found in 7.5% of the control subjects (P =.016). In general, the prevalence of these abnormalities was 1.5 to 2 times higher in patients who were delivered before 28 weeks, in comparison with patients who were delivered after 28 weeks. CONCLUSIONS: Hemostatic abnormalities, associated with an increased risk of thrombosis, are present in approximately 40% of patients with a history of severe preeclampsia, which is almost 4 times higher than in control subjects. These findings might suggest a cause of preeclampsia and could have implications in subsequent pregnancies and general health.

Antibodies, Anticardiolipin↗
PubMed1999

Corticosteroids do not influence ovarian responsiveness to gonadotropins in patients with premature ovarian failure: a randomized, placebo-controlled trial.

OBJECTIVE: To determine the effect of corticosteroids on ovarian responsiveness to exogenous gonadotropins in patients with idiopathic premature ovarian failure (POF). DESIGN: Placebo-controlled, randomized, double-blind, multicenter study. SETTING: Two tertiary care academic centers for reproductive endocrinology and fertility and two general teaching hospitals. PATIENT(S): One hundred patients with idiopathic POF intended to enter the study. The study was discontinued after 36 patients failed to ovulate. INTERVENTION(S): Endocrine and immune parameters were tested on days 1 and 15. On day 1, subjects were randomized to receive either 9 mg of dexamethasone daily or placebo. From day 5 onward, 300 IU of hMG daily was added for 10 days in both groups. The dosage of dexamethasone was decreased stepwise in the second week and discontinued after day 15. Patients were monitored by transvaginal ultrasonography and by determining serum E2 levels. MAIN OUTCOME MEASURE(S): Ovulation rate. Fifty patients would have to be included in each study group to detect a statistically significant difference of 20% in the ovulation rate between the two groups with alpha = 0.05 and beta = 0.1 (one-tailed test). RESULT(S): No ovulation was recorded in the first 36 patients. Interim analysis showed that the 95% confidence intervals of an ovulation rate of 0 were 0-17% for the dexamethasone arm (n = 19) and 0-19% for the placebo arm (n = 17). Because the preset objective (a difference of 20%) would never be reached, the study was discontinued. CONCLUSION(S): Corticosteroids do not influence ovarian responsiveness to gonadotropins in patients with idiopathic POF.

Adrenal Cortex Hormones↗
PubMed1999

A prospective randomized study of the systemic immune response after laparoscopic and conventional Nissen fundoplication.

BACKGROUND: Laparoscopic techniques are thought to reduce the postoperative immunologic and metabolic changes of conventional operations. Until now, the only clinical data available were obtained from patients operated on for symptomatic gallstones; moreover, few studies were randomized. This randomized prospective study compares the systemic immune response after laparoscopic and conventional Nissen fundoplication. METHODS: Seventeen patients scheduled for Nissen fundoplication were randomly assigned to undergo either a laparoscopic or a conventional procedure. Postoperative inflammatory response was assessed by measuring the white blood cell count, C-reactive protein, and soluble tumor necrosis factor receptors p55 and p75. Postoperative immune function was assessed by measuring monocyte HLA-DR expression and the stress response was assessed by measuring plasma cortisol concentrations. RESULTS: Laparoscopic surgery resulted in significantly lower plasma CRP levels 1 day after surgery. Both approaches resulted in a significant decrease in HLA-DR expression within 2 hours after surgery. After the laparoscopic approach, postoperative expression was restored to preoperative values within 1 day after surgery. However, after conventional surgery HLA-DR expression remained suppressed and did not return to preoperative values until the fourth postoperative day. No significant differences between the 2 procedures were observed in white cell blood count, sTNFr-p55 and p75, nor in postoperative cortisol levels. CONCLUSIONS: Although both laparoscopic and conventional Nissen fundoplication result in an activation of the systemic immune response, this study suggests that this response could be less after the laparoscopic approach. The differences found may reflect a lower risk for postoperative infective complications.

Adult↗
PubMed1999

Effect of 50- and 100-mg vitamin E supplements on cellular immune function in noninstitutionalized elderly persons.

BACKGROUND: It has been suggested that vitamin E can counteract the age-associated decline in cellular immune responsiveness (CIR). Particularly, T helper cell type 1 (Th1) activity, ie, interferon (IFN) gamma-producing Th1 activity and, hence, delayed-type hypersensitivity (DTH) would be enhanced by vitamin E supplementation. OBJECTIVE: Our aim was to study the effects of 6 mo supplementation with 50 and 100 mg vitamin E on CIR in the elderly. DESIGN: A double-blind, placebo-controlled trial was conducted in 161 healthy elderly subjects aged 65-80 y. CIR was measured in vivo by means of DTH skin tests and in vitro by assessing the production of interleukin (IL) 2, IFN-gamma (a typical Th1 cytokine), and IL-4 (a typical Th2 cytokine) by peripheral blood mononuclear cells after stimulation with phytohemagglutinin. RESULTS: Both DTH and IL-2 production showed a trend toward increased responsiveness with increasing dose of vitamin E. However, IFN-gamma production decreased whereas IL-4 production increased in the groups receiving vitamin E. Only the change in the number of positive DTH reactions was borderline significantly larger in the 100-mg vitamin E group than in the placebo group (P = 0.06, Bonferroni adjusted). Subjects receiving 100 mg vitamin E with low baseline DTH reactivity or who were physically less active had a significantly larger increase in the cumulative diameter of the skin induration resulting from the DTH test than did the placebo group (P = 0.03), although this difference was not significant after Bonferroni correction (P = 0.07). CONCLUSION: Possible beneficial effects of 100-mg vitamin E supplementation may be more pronounced in particular subgroups of elderly subjects.

Aged↗
PubMed1999

Sensitivity of antiendomysium and antigliadin antibodies in untreated celiac disease: disappointing in clinical practice.

OBJECTIVE: We have undertaken a study to assess the efficiency of serological tests in the diagnosis of celiac disease (CD) during the period January 1, 1994 to January 7, 1997. Our aim was to evaluate the sensitivity of IgA antiendomysium (EMA) and IgA antigliadin (AGA) with regard to the degree of histological abnormality in biopsy specimens of small intestine in untreated celiac disease patients and first-degree relatives. METHODS: The study population comprised 101 cases: 85 untreated celiac patients and 16 first-degree relatives with a mean age of 42 yr (range, 2-76 yrs). Sixteen of 85 were excluded from study because they did not satisfy the study or diagnostic criteria of CD. EMA and AGA have been compared with the degree of villous atrophy (VA) in 69 celiac patients and 16 relatives according to the Marsh criteria of 1992. We divided the Marsh III histology into three subgroups as follows: Marsh IIIa (partial VA), Marsh IIIb (subtotal VA), and Marsh IIIc (total villous atrophy). RESULTS: The specificity and positive predictive value of EMA for CD was excellent, because all EMA-positive patients (n = 42) were diagnosed with CD. The sensitivity of EMA, however, differed between CD subgroups; in patients with total VA, the sensitivity of EMA was 100% (17/17). However, in patients with partial VA (Marsh IIIa), the sensitivity of EMA was disappointing, only 9/29 (31%). Three of 72 celiacs with Marsh IIIb and Marsh IIIc had IgA deficiency and were excluded from the study. Elevated AGA has been detected in the sera of 39 of 69 (62%) patients. A combination of EMA and AGA tests showed a sensitivity of 76% (53/69). None of 16 first-degree relatives with Marsh I-II had positive EMA. CONCLUSIONS: Interpretation of negative serology needs great awareness. Although EMA sensitivity in total villous atrophy is excellent, in partial villous atrophy the sensitivity of EMA appears to be disappointing. Our experience shows that EMA and AGA have only limited value in screening programs for CD.

Adult↗
PubMed1998

Increased production of tumor necrosis factor alpha, and not of interferon gamma, preceding disease activity in patients with multiple sclerosis.

OBJECTIVE: To study whether tumor necrosis factor (TNF) alpha or interferon (IFN) gamma production by stimulated white blood cells precedes or accompanies clinical and magnetic resonance imaging signs of disease activity in patients with multiple sclerosis. DESIGN: Prospective study with a follow-up of 9 months. SETTING: Patients visiting an outpatient university clinic. PATIENTS: The 30 Amsterdam-based patients (28 completing all evaluations) participating in a multicenter, randomized, placebo-controlled, double-blind trial of a chimeric anti-CD4 antibody in the treatment of active relapsing-remitting and secondary progressive multiple sclerosis. Patients in both treatment arms were included, because for these patients anti-CD4 treatment in this study did not affect TNF-alpha and IFN-gamma production and did not reduce signs of disease activity on magnetic resonance imaging. MAIN OUTCOME MEASURE: Distribution of classes of TNF-alpha and IFN-gamma production (expressed as z scores) in patients with or without clinical or magnetic resonance imaging signs of disease activity. RESULTS: One month preceding exacerbations of multiple sclerosis, there was a shift toward higher z scores of TNF-alpha production (P<.05), but not of IFN-gamma production. There was no statistically significant relationship between IFN-gamma and TNF-alpha production and magnetic resonance imaging markers of multiple sclerosis activity. CONCLUSION: The production of TNF-alpha, and not of IFN-gamma, is significantly higher in patients with multiple sclerosis before exacerbations than in patients with stable disease. Although present, this relationship is too weak to use TNF-alpha production as a surrogate marker of disease activity in multiple sclerosis.

Adult↗
PubMed1998

Cross-reactivity patterns of contact-sensitizing methacrylates.

Methacrylates are well-known contact sensitizers with increasing frequency of contact leading to occupational skin disease. Here, we developed an animal model to facilitate studies on the sensitizing capacities and cross-reactivity patterns between four clinically most important allergens: methacrylate (MMA), 2-hydroxyethyl methacrylate (2-HEMA), 2-hydroxypropyl methacrylate (2-HPMA) and ethyleneglycol dimethacrylate (EGDMA). Inbred guinea pigs were immunized by ic injections of 300 microliters of 1.0 M methacrylate solutions in Freund's complete adjuvant into both flanks, both ears, and the neck. After 14 days open skin tests were performed with 50% MMA, 2-HEMA, or 2-HPMA or 10% EGDMA solutions in 40% DMSO in ethanol. Cross-reactivities were investigated 14 days later by skin testing with all four methacrylates. Using this newly developed protocol, strongly positive skin tests for methacrylates could be induced in almost all guinea pigs (MMA 26/26, 2-HEMA 16/18, 2-HPMA 15/16 and EGDMA 11/11). Whereas EGDMA induced only weak or infrequent cross-reactivities, 2-HEMA sensitization led to strong cross-reactions to all other methacrylates. Both MMA and 2-HPMA induced strong cross-reactivity to EGDMA but only weak to moderate reactivities to the other methacrylates. The absence of strong cross-reactions with monomethacrylates in EGDMA (dimethacrylate)-sensitized animals may be explained by the predominance of highly EGDMA-specific T-cells in these animals. In contrast, sensitization with MMA, 2-HEMA, and 2-HPMA would lead to recruitment of T-cells cross-reactive to the other monomethacrylates, according to their molecular similarities. The strong skin hypersensitivities observed for EGDMA in these latter groups are ascribed to enzymatic degradation into monomethacrylate compounds, notably 2-HEMA, at a rate sufficient to elicit cognate effector T-cells. The results of this study offer new insights in the development of methacrylate hypersensitivities and common cross-sensitization patterns in clinical practice.

Allergens↗
PubMed1998

SAT and serology in adult coeliacs, seronegative coeliac disease seems a reality.

UNLABELLED: The aim of this study was to assess the correlation of sugar absorption test (SAT) using Lactulose/Mannitol/Sucrose (LMS), with IgA-endomysium (EMA), and IgA-gliadin (AGA) antibodies in relation to the severity of the intestinal mucosal damage in adult coeliacs. We have differentiated the Marsh classification in partial villous atrophy (VA) (III a), subtotal VA (III b), and total VA (III c). Twenty-nine untreated adults coeliacs, with a mean age of 47 years, range 20-76 yrs were studied over 3 years. SAT, IgA-AGA and IgA EMA were performed in 29 consecutive coeliac patients with villous atrophy on a gluten containing diets. RESULTS: Histopathological evaluation of small intestinal mucosa showed a partial VA in 14/29, subtotal VA in 10/29 and total VA in 5/29. All coeliacs with total VA had positive EMA (5/5 100%). However in coeliacs with partial VA sensitivity of EMA was poor (4/14 29%). Sensitivity of EMA in patients with subtotal VA was 50% (5/10). AGA was raised in 3/14 (21%), 6/10 (60%), and in 4/5 (80%) coeliacs with partial, subtotal and total VA respectively. AGA was raised in 13/29 (sensitivity 45%). SAT was abnormal in 26/29 (sensitivity: 89%). One patient had abnormal SAT, EMA and AGA. Eleven of 29 patients (38%) were negative for AGA and EMA, but SAT was abnormal in 10 of them. One patient was positive for EMA, negative for AGA, normal for SAT. EMA and/or AGA were positive in 18/29 (sensitivity 62%). Our study suggests that negative predictive value of serology should be interpreted cautiously since coeliacs with partial VA are negative in serology. Over the last ten years SAT and EMA have been accepted as screening tools for CD. SAT seems to be more sensitive than serology. However there is no standardized agreement in the literature for serology and SAT. A combination of SAT and serology may provide a good sensitivity in order to detect that subgroup of coeliacs with milder histopathological abnormality.

Adult↗