PubMed Health⌕ Search

Biomedical subjects

Franziska Ruëff

Publications and source records attributed to Franziska Ruëff.

11 recordsLinked to original sources
PubMed2006

Relevance of the recombinant lipid transfer protein of Hevea brasiliensis: IgE-binding reactivity in fruit-allergic adults.

BACKGROUND: Lipid transfer proteins (LTPs) are relevant allergens in certain plants. The role of the LTP of Hevea brasiliensis in the latex-fruit syndrome is widely unknown. OBJECTIVE: To study IgE reactivity with recombinant Hevea LTP in sera of fruit-allergic adults with and without natural rubber latex (NRL) allergy. METHODS: An LTP-specific complementary DNA of H brasiliensis leaves was amplified, subcloned into the pMAL expression system, and analyzed. The recombinant protein was coupled to ImmunoCAP, and the IgE-binding properties were studied in sera of 10 NRL-allergic patients without symptoms to fruit and 48 atopic patients with fruit allergy. Eleven of these 48 patients were also allergic to NRL, 14 displayed sensitization to NRL without symptoms on NRL exposure so far, and 23 had neither symptoms nor IgE antibodies to NRL. RESULTS: After expression in Escherichia coli, a soluble maltose-binding protein-rHev b 12 fusion protein was isolated and coupled to ImmunoCAP to determine rHev b 12 specific IgE reactivity. rHev b 12 specific IgE binding was found in 3 fruit-allergic patients with NRL sensitization (0.68, 0.88, and 0.96 kU/L) and in 3 fruit-allergic patients without NRL sensitization (1.58, 2.25, and 2.27 kU/L). The remaining 52 serum samples and all maltose-binding protein control test results were negative (< 0.35 kU/L). CONCLUSIONS: In these patients, rHev b 12 specific IgE reactivity seems to result from common cross-reactive epitopes with some of the fruit LTPs tested and underscores only an involvement in co-recognition. No clinical relevance of IgE binding to the LTP of H brasiliensis in association with NRL allergy was detected.

Adolescent↗
PubMed2006

Mastocytosis and Hymenoptera venom allergy.

PURPOSE OF REVIEW: Mastocytosis is a rare disease characterized by increased mast cells in skin and/or internal organs. We evaluate the impact of mastocytosis on diagnosis and treatment of Hymenoptera venom allergy. RECENT FINDINGS: Patients with Hymenoptera venom allergy who suffer from mastocytosis develop life-threatening sting reactions more often than those who do not. When patients with Hymenoptera venom allergy were systematically examined for mastocytosis, it was found to be represented to an abnormally high extent. Most patients with mastocytosis tolerate venom immunotherapy with no or only minor systemic symptoms. Venom immunotherapy was found to be marginally less effective in patients with mastocytosis than in those without evidence of mast cell disease (defined as absent cutaneous mastocytosis combined with a serum tryptase concentration of <11.4 microg/l). Several deaths from sting reactions were reported in patients with mastocytosis after venom immunotherapy was stopped. These patients should have venom immunotherapy for the rest of their lives. SUMMARY: Patients suffering from mastocytosis and Hymenoptera venom allergy are at risk from a particularly severe sting anaphylaxis. They need optimal diagnosis and treatment. In patients presenting with Hymenoptera venom allergy, screening tests by measurement of serum tryptase concentration, and a careful skin examination, are highly recommended.

Animals↗
PubMed2005

Anaphylaxis to viscotoxins of mistletoe (Viscum album) extracts.

BACKGROUND: Extracts of mistletoe (Viscum album) are used in many countries for adjuvant cancer therapy. These extracts contain mistletoe lectins and viscotoxins that are supposed to have immunostimulating and cytotoxic effects, respectively. The treatment is usually well tolerated. OBJECTIVE: To report a case of severe anaphylaxis secondary to mistletoe extract administration with demonstrable anti-IgE antibodies to mistletoe. METHODS: Skin prick tests, basophil histamine release, basophil activation test, and immunoblotting were performed to characterize the pathophysiology of this reaction. RESULTS: The patient had immediate-type skin prick test reactions to the whole commercial preparation and to its mistletoe extract component. A histamine release test and a flow cytometric basophil activation test performed with the patient's peripheral blood leukocytes by incubation with the mistletoe extract yielded a concentration-dependent histamine release and expression of the activation marker gp53 in up to 98% of anti-IgE-positive cells. Immunoblotting revealed IgE binding to 5-kDa proteins of mistletoe in the patient's serum, which corresponds to the molecular weight of viscotoxins. The results of all these tests were negative in controls. CONCLUSIONS: Until now, anaphylaxis to mistletoe extracts has been only rarely reported. In our patient, viscotoxin specific IgE evidently had induced an anaphylactic reaction.

Anaphylaxis↗
PubMed2005

Baseline serum levels of mast cell tryptase are raised in hemodialysis patients and associated with severity of pruritus.

BACKGROUND: The pathogenesis of pruritus in renal disease is not yet understood. Evidence suggests that mast cells play a role; for example, the number of dermal mast cells is increased in patients on hemodialysis. PATIENTS AND METHODS: To investigate a possible role of mast cell tryptase in pruritus of patients undergoing chronic hemodialysis, serum mast cell tryptase concentrations were measured in blood samples taken from 93 such patients, 53 of whom also recorded the severity of their pruritus on a visual analogue scale. RESULTS: Serum mast cell tryptase levels were above 11.4 microg/l (95th percentile) in 84 of 93 hemodialysis patients (90.3 %). The intensity of pruritus correlated significantly (p = 0.014) with the tryptase levels, an associated not yet shown for other mast cell-related parameters. CONCLUSIONS: Mast cells or even tryptase itself may be involved in the pathogenesis of pruritus of hemodialysis patients.

Adolescent↗
PubMed2004

Effect of reduced exposure on natural rubber latex sensitization in health care workers.

BACKGROUND: Knowledge about the long-term course of allergy or sensitization to natural rubber latex (NRL) is insufficient. OBJECTIVE: To investigate the long-term effect of preventive measures on sensitization variables in health care workers who had been diagnosed as having NRL allergy (NRLA) or NRL sensitization (NRLS) without clinical symptoms. METHODS: Repeated follow-up investigations, skin prick tests, and NRL specific IgE serum antibodies were performed in 88 health care workers-33 with NRLA and 55 with NRLS. All workers had been instructed to avoid NRL exposure. At the workplace, powder-free NRL gloves for all other employees were gradually introduced. Re-evaluations were done at 14 +/- 3.7 (N = 86) and 38 +/- 4.0 (N = 78) months after the first examination. RESULTS: At the last follow-up, a loss of skin prick test reactivity to NRL was observed in 1 of 29 subjects with NRLA (3.4%) and 16 of 35 with NRLS (45.7%) with previous skin test reactions (P < .001). Among those subjects who demonstrated a kU/L level (CAP class) equal to or greater than class I to NRL at the initial examination, NRL-specific IgE was absent at the last follow-up in 8 (32.0%) of 25 subjects with NRLA and 14 (38.9%) of 36 with NRLS. At the final examination, we could no longer demonstrate sensitization to NRL by any method in 24 (27.3%) of 88 health care workers. Complete loss of NRL sensitization was less frequent in subjects with NRLA than in those with NRLS (1 of 33 or 3.0% vs 23 of 55 or 41.8%; P < .001). CONCLUSIONS: Implementation of simple preventive measures lowers markers of sensitization to NRL quickly in many health care workers with NRLA or NRLS.

Adult↗
PubMed2004

Venom immunotherapy: adverse reactions and treatment failure.

PURPOSE OF REVIEW: Side effects of venom immunotherapy and lack of efficacy represent significant problems in the treatment of patients allergic to Hymenoptera venom. Among these side effects systemic anaphylactic reactions and large local reactions are the most important. This review aims to discuss new insights in frequency, pathogenesis and handling of these common side effects and of treatment failure during venom immunotherapy. RECENT FINDINGS: Several studies showed that severe side effects due to venom immunotherapy are rare. Recently published studies focus on ultrarush protocols and report good tolerance of an ultrarush venom immunotherapy in which the maintenance dose was reached within several hours or 2 days, respectively. Compared to the use of aqueous extracts (administered according to a rush protocol), frequency of local and also systemic side effects was lower when depot extracts and schedules with a slow conventional dose increase were applied. Concomitant treatment with H1-antihistamines was found to reduce local and mild systemic adverse reactions during venom immunotherapy. Up to 25% of patients are not protected when re-stung while on venom immunotherapy with the usual maintenance dose of 100 microg of venom every 4-8 weeks. These patients can achieve full protection by increasing the maintenance dose. SUMMARY: Conventional dose increase using depot extracts is better tolerated than if aqueous extracts are being administered. Concomitant treatment with H1-antihistamines may be helpful. Increasing the venom dose to 200 microg or even more may be therapeutically effective in patients not protected by a lower maintenance dose. To compare tolerance of different treatment protocols prospective comparative studies are required.

Histamine H1 Antagonists↗
PubMed2003

[Insect venom allergies].

Systemic IgE-mediated immediate type reactions (anaphylaxis) due to honeybee or vespid stings are potentially life-threatening; they are reported in up to 5% of the general population. Insect venom allergy is diagnosed by history, skin testing and measurement of insect venom-specific serum IgE; sometimes additional tests are needed. The diagnosis is based on the history of a systemic allergic immediate type sting reaction, without such a medical history any other "positive" test results are irrelevant. Nearly always, patients with systemic allergic sting reactions can be protected from further episodes of anaphylaxis by a carefully performed hyposensitization (specific immunotherapy). If therapeutic efficacy has been proven by tolerance of a re-sting, hyposensitization can be frequently stopped after 3 to 5 years. Patients with a particular risk of frequent re-stings or of very severe sting reactions may have to be treated for a longer time, some of them even life-long.

Animals↗
PubMed2002

HLA-DQ8 and the HLA-DQ8-DR4 haplotype are positively associated with the hevein-specific IgE immune response in health care workers with latex allergy.

BACKGROUND: Hevein is one of the most important latex allergens affecting health care workers (HCWs). OBJECTIVE: Because the genetically determined susceptibility is one important factor regulating type I allergy, the association between the hevein-specific IgE immune response and HLA class II alleles of DQB1 and DRB1, DRB3, DRB4, and DRB5 was studied. METHODS: The distribution of HLA-DQB1 and DRB1, DRB3, DRB4, and DRB5 in 269 HCWs with latex allergy, 56 latex-sensitized patients with spina bifida (SB), and 90 nonatopic control subjects under special consideration for hevein-specific IgE was examined. RESULTS: Seventy percent (189/269) of the HCWs with latex allergy and 39% (22/56) of the latex-sensitized patients with SB had increased hevein-specific IgE antibody concentrations (>0.35 kU/L). HLA data analysis revealed significantly increased phenotype frequencies for DQB1*0302 (DQ8; 91/189 [48%]) and DRB1*04 (DR4; 102/189 [54%]) in hevein-positive HCWs with latex allergy compared with the 80 hevein-negative HCWs with latex allergy (DQB1*0302: 16/80 [20%], corrected P value [P (c)] = 7.1 x 10(-4); DRB1*04: 23/80 [29%], P (c) =.01) and with control subjects (DQB1*0302: 16/89 [18%], P (c) = 1 x 10(-4); DRB1*04: 22/90 [24%], P (c) = 3.2 x 10(-4)). The DQ8-DR4 haplotype frequency was significantly elevated in HCWs with hevein-specific IgE antibodies when compared with that in HCWs without hevein-specific IgE antibodies (47% vs 18%, P (c) = 5.3 x 10(-4)) or control subjects (47% vs 18%, P (c) = 9.6 x 10(-4)). In contrast, latex-sensitized patients with SB with hevein-specific IgE antibodies showed an increased but not significant DQB1*0302 frequency (7/22 [32%] vs 2/34 [6%], P =.02, P (c) = not significant) compared with that seen in those without hevein-specific IgE antibodies. CONCLUSION: The DQB1*0302 (DQ8) alone, the DQB1*0302 (DQ8)-DRB1*04 (DR4) haplotype, or both are significantly involved in the hevein-specific IgE immune response in HCWs with latex allergy.

Adult↗