Recombinant allergens. Steps on the way to diagnosis and therapy of type I allergy.
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Individuals suffering from immediate hypersensitivity (type-I allergy) to a particular pollen frequently display intolerance to several foods of plant origin. In this respect, individuals sensitized to birch pollen and/or mugwort pollen frequently display type-I allergic symptoms after ingestion of celery. In this study, we expressed the major allergenic protein of celery, Api g 1, which is responsible for the birch-celery syndrome, in the form of a non-fusion protein. The open reading frame of the cDNA of Api g 1 codes for a protein of 153 amino acids with a molecular mass of 16.2 kDa and 40% identity (60% similarity) to the major allergen of birch pollen, Bet v 1. Furthermore, Api g 1 exhibited similar characteristics to (a) two proteins in parsley induced by fungal infection, (b) the major tree pollen allergens and (c) pathogenesis-related and stress-induced proteins in other plant species. The reactivity of recombinant Api g 1 with IgE antibodies present in sera from celery intolerant patients was comparable to that of the natural celery allergen. Cross-reactivity with Bet v 1 was proven by cross-inhibition experiments, which provides further support for the existence of the birch-celery syndrome and for the suggestion that allergies to some vegetable foods are epiphenomena to allergies caused by inhalation of tree pollen.
Up to 20% of the population in industrialized countries suffer from type I allergic symptoms (rhinitis, conjunctivitis, and bronchial asthma). The cDNA coding for birch pollen profilin, a highly conserved cross-reactive allergen and actin-binding protein was expressed in Escherichia coli. Upon induction with IPTG up to 30 mg recombinant profilin per liter culture could be obtained. A single step purification protocol based on the high affinity of profilin to poly-(L-proline) Sepharose was used to obtain large amounts of soluble and pure recombinant birch profilin. Recombinant birch pollen profilin specifically bound IgE, elicited dose dependent histamine release from patients basophils and could be used for skin prick testing without toxic effects. The results indicate that by using purified recombinant profilin, specific diagnosis of type I allergy might be improved.
The number of tree-pollen-allergic patients showing allergic reactions to apples, various vegetables and nuts is increasing. In this paper the molecular characterization of the major apple allergen, Mal d 1, is reported. The cDNA coding for Mal d 1 was cloned and sequenced. Its open reading frame codes for a protein of 159 amino acids with a predicted molecular mass of 17.7 kDa and a predicted pI of 5.9. Sequence comparison to Bet v 1, the major birch pollen allergen, revealed 64.5% identity on the amino acid level and 55.6% identity on the nucleic acid level. Recombinant Mal d 1 was expressed in the plasmid pMW 175 in E. coli BL 21 (DE3) and its immunological properties were tested. Crossreactivity with Bet v 1 was shown by inhibition assays.
Transrectal high-intensity focused ultrasound (HIFU) was recently established as a highly effective means of inducing contact and irradiation-free intraprostatic coagulative necrosis. This technique, therefore, appears potentially useful for treating localized prostate cancer (PC). To evaluate this issue, a total of 29 human prostates with localized cancer was subjected to HIFU treatment in vivo before radical retropubic prostatectomy. HIFU therapy was performed with the use of HIFU transducers with focal lengths of 3.0 cm (n = 3), 3.5 cm (n = 19), and 4.0 cm (n = 7), and the site intensity was varied from 1260 to 2000 W/cm2. The extent of intraprostatic necrosis was determined by planimetrical analysis of whole mount prostatic sections. Transrectal HIFU consistently induced sharply delineated intraprostatic coagulative necrosis within the target area, whereas alterations of perioprostatic structures were never observed. The cross-sectional area of necrosis increased from 1.1 +/- 0.7 cm2 (SD; n = 3; 3.0-cm focal length; 1428 W/cm2) to 1.2 +/- 0.7 cm2 (n = 2; 3.5-cm focal length; 1428 W/cm2), 1.8 +/- 0.17 cm2 (n = 8; 3.5-cm focal length; 1680 W/cm2), 2.8 +/- 0.32 cm2 (n = 9; 3.5-cm focal length; 2000 W/cm2) and 3.8 +/- 0.4 cm2 (n = 7; 4.0 cm focal length; 1260 W/cm2). HIFU beam transmission and the therapeutic effect were comparable in benign and malignant prostatic tissue. Interstitial thermometry (n = 6) revealed maximum intraprostatic temperatures in the focal zone up to 98.6 degrees C. Outside the focal zone and on the rectal wall, no significant temperature rises were noted. Subsequently, HIFU was applied to unilateral histologically proven T2a/T2b PC (n = 10) in an attempt to destroy all cancer before radical retropubic prostatectomy. PC was always correctly targeted. In 7 individuals, PC was partially (mean, 53%; range, 38-77%) destroyed; in the remaining 3 cases the entire tumor was ablated. Although these histological data permit no definitive conclusion on the clinical efficacy of this approach, transrectal HIFU seems to be an attractive novel minimally invasive treatment option for localized PC.
We report on a primigravida, who was admitted in the 14th week of pregnancy because of recurrent vomiting and upper abdominal pain. The diagnosis of a large 20 cm echinococcal cyst of the liver was confirmed by ultrasound and an indirect hemagglutination test (IHA). In the 19th week of pregnancy a subtotal cystectomy was performed under perioperative treatment with the anthelmintic drug Albendazole. The patient delivered a 1420 g, 41 cm premature boy in breech position at 33 weeks. The significance of echinococcal cysts in pregnancy is discussed.
BACKGROUND: The use of peptides representing T-cell epitopes of allergens is a modern concept for improvement of specific immunotherapy. A prerequisite for this approach is the identification of T-cell epitopes of atopic allergens. METHODS: T-cell lines and 40 T-cell clones (TCC) specific for Phl p 1, the group I allergen of timothy grass (Phleum pratense), were established from the peripheral blood of nine patients allergic to grass pollen and mapped for epitope specificity by using overlapping dodecapeptides. Phenotype and cytokine production profile of TCC were investigated. Representative TCC were analyzed for HLA-restriction, T-cell receptor V beta gene usage, and crossreactivity with grass pollen extracts from Dactylis glomerata, Poa pratensis, Lolium perenne, Secale cereale, and selected amino acid sequence-derived peptides. RESULTS: Patients displayed IgE binding to all grass species investigated. Forty TCC were established. Fifteen T-cell epitopes could be identified on Phl p 1. Of 40 TCC, 39 displayed the helper cell (Th) phenotype; one clone was CD8+. Specific stimulation induced a Th2-like type of cytokine production in 20 of 39 TCC. Crossreactivity studies revealed crossreacting and non-crossreacting T-cell epitopes. CONCLUSION: Phl p 1, a major grass pollen allergen, harbors multiple T-cell epitopes. Species-specific and crossreacting T-cell epitopes exist among group I allergens of grasses. Epitope recognition patterns could not be correlated with particular HLA haplotypes. A restricted T-cell receptor V beta gene usage was not observed.
BACKGROUND: Interleukin (IL)-4 and IL-13 have been shown to be potent switch factors for IgE synthesis in human B cells. OBJECTIVE: In this study we investigated the effects of recombinant human IL-4 and IL-13 on total and allergen specific IgE synthesis by peripheral blood mononuclear cells (PBMC) from pollen allergic patients and healthy control individuals. METHODS: Peripheral blood mononuclear cells (PBMC) from allergic patients were investigated for their capacity to produce allergen specific IgE in vitro. Total protein extracts from birch pollen and timothy grass pollen as well as purified recombinant birch pollen allergens, Bet v I, birch profilin (Bet v II) and recombinant timothy grass pollen allergens, Phl p I, Phl p II, and Phl p V were used to measure specific IgE-antibody synthesis in cell culture supernatants by IgE-immunoblot and ELISA. RESULTS: PBMC obtained from allergic patients spontaneously secreted allergen specific IgE in the culture supernatants. Addition of Interleukin 4, Interleukin 13 and anti-CD40 antibody to the cultures alone or in combinations significantly induced total IgE production whereas allergen specific IgE production was not affected. CONCLUSION: Our results indicate that the peripheral blood of allergic individuals contains long lived allergen specific B cells which have already switched to IgE production and which are not sensitive to IL-4 and IL-13 treatment. These results may have implications on attempts to use cytokines or cytokine antagonists in therapy of Type I allergy.
Acquired renal cystic disease (ARCD) has a prevalence of up to 90% in patients with endstage renal failure and an uncommonly high potential of developing into renal cell carcinoma. After renal transplantation, regression of an established ARCD is possible, suggesting a protective effect of transplantation against tumors in the native kidneys. Two case reports describing hypernephromas in kidneys with ARCD 3 years after successful renal transplantation are presented. One patient died 6 weeks after nephrectomy due to metastatic disease, although there were no metastases at the time of operation. The other patient lives with no evidence of disease since 10 months. This report confirms the need of annual sonography of the native kidneys also in renal transplant patients with consecutive computed tomography scanning of suspicious lesions.
Podocyte injury is believed to contribute to glomerulosclerosis in membranous nephropathy. To identify the factors involved, we investigated the effects of basic fibroblast growth factor (bFGF), a cytokine produced by podocytes, on rats with membranous nephropathy (passive Heymann nephritis [PHN]). All rats received a daily i.v. bolus of 10 microg bFGF or vehicle from days 3-8 after PHN induction. In proteinuric PHN rats on day 8, bFGF injections further increased proteinuria. Podocytes of bFGF-injected PHN rats showed dramatic increases in mitoses, pseudocyst formation, foot process retraction, focal detachment from the glomerular basement membrane, and desmin expression. bFGF injections in PHN rats did not alter antibody or complement deposition or glomerular leukocyte influx. bFGF-injected PHN rats developed increased glomerulosclerosis when compared with control PHN rats. Also, bFGF induced proteinuria and podocyte damage in rats injected with 10% of the regular PHN-serum dose. None of these changes occurred in bFGF-injected normal rats, complement-depleted PHN rats or rats injected with 5% of the regular PHN serum dose. These divergent bFGF effects were explained in part by upregulated glomerular bFGF receptor expression, induced by PHN serum. Thus, bFGF can augment podocyte damage, resulting in increased glomerular protein permeability and accelerated glomerulosclerosis. This bFGF action is confined to previously injured podocytes. Release of bFGF from glomerular sources (including podocytes themselves) during injury may represent an important mechanism by which podocyte damage is enhanced or becomes self sustained.
To determine the morphologic impact and safety of high-intensity focused ultrasound (HIFU) administered transrectally for tissue ablation, a total of 22 prostates were treated in vivo with transrectal HIFU prior to surgical removal. Location and size of the tissue lesions correlated well with the predefined target area and revealed sharply delineated coagulative necrosis in all cases. In a subsequent phase II clinical trial the clinical effectiveness of transrectal HIFU as a minimally invasive treatment modality for patients with symptomatic benign prostatic hyperplasia (BPH; n = 50) was studied. The maximum urinary flow rate (Qmax, ml/s) increased from 8.9 +/- 0.6 (n = 50; mean +/- SEM) to 12.8 +/- 0.9 (3 months, n = 46), 11.9 +/- 0.9 (6 months, n = 44) and 12.2 +/- 1.0 (12 months, n = 32). Within the same time period, the post-voiding residual volume (ml) decreased from 113 +/- 17 (mean +/- SEM) to 47 +/- 6, 57 +/- 7, and 49 +/- 6. These data demonstrate that transrectal HIFU can induce intraprostatic coagulative necrosis. The phase-II clinical data presented in this paper reveal that transrectal HIFU is an effective and safe minimally invasive treatment option for BPH. Nevertheless, a randomised phase-III trial comparing HIFU and TURP is mandatory to define the definitive role of transrectal HIFU in BPH, and is presently planned.
Hemangiomas of the upper aerodigestive tract may present a therapeutic challenge depending on their size, location and symptoms. We present a rare case of cavernous hemangioma of the aryepiglottic fold applaning in an adult. First symptoms were dysphagia and hoarseness. Surgical removal was performed with a CO2/Nd: YAG combination laser under microscopic control. After a regular postoperative course the patient has remained disease-free after a 2 year follow up period. We suggest the use of the CO2/Nd: YAG combination laser as preferred treatment in cases of exophytic hemangiomas, because of the favorable combination of excision with photocoagulation effects.
An epitope expression cDNA library was constructed from the randomly fragmented cDNA coding for Phl p I, the major grass pollen allergen. Using IgE from allergic patients, epitope clones were isolated and immunodominant fragments were selected. Among three epitope clones coding for a similar region of Phl p I, one clone expressed a 15-amino-acid epitope which was target for IgE antibodies from approximately 30% of grass pollen allergic patients. According to the prevalence of grass pollen allergy, 22% of all allergic patients are expected to display IgE reactivity with this epitope. Although the purified recombinant epitope specifically bound IgE, it did not release histamine from basophiles of most grass pollen allergic patients and thus represents an IgE hapten. Immunodominant IgE haptens may be useful as therapeutic agents to saturate mast cell-bound IgE prior to allergen exposure and may represent candidates for a safe immunotherapy of allergic diseases by reducing anaphylactic side effects.
A 22-year-old woman was hospitalized because of fever of 39 degrees C and increasing dyspnoea. The chest radiograph demonstrated coarse confluent opacities bilaterally. Despite antibiotic treatment the condition deteriorated acutely after 2 days. All efforts to find an infectious agent, including immunological tests, were unsuccessful. Artificial ventilation became necessary because of increasing respiratory failure with an arterial oxygen partial pressure of 56 mm Hg, CO2 of 41 mm Hg and a respiratory rate of 60/min. Histological examination of a transthoracic lung biopsy revealed bronchiolitis obliterans organizing pneumonia, which was treated with prednisolone. The initial dose was 500 mg/d, gradually reduced to 12.5 mg/d over 2 weeks. The clinical and radiological findings improved markedly after 2 days and the patient discharged herself after 3 weeks and there was no follow-up.
A pulsed holmium:YAG laser (lambda = 2120 nm) was used to reopen the basal turn of artificially obliterated human cochleas in freshly dissected cadavers. This allowed intracochlear insertion of the stimulation electrode of a cochlear implant under simulated surgical conditions. Laser energy was transmitted through a 400-microns nylon fiber via the opened facial recess directly to the round window niche. At an energy level of 500 mJ per 2.5 microseconds pulse, a repetition rate of 2 Hz, and an exposure time of 20-30 s, the photo-ablative mechanism of laser-bone interaction led to a 8-10 mm recanalization of the basal turn of the cochlea without damaging surrounding structures. The artificial bony occlusion and the recanalized basal turn of the cochlea were visualized by means of computed tomography and studied under light microscopy, using a histologic thin-section technique.
No information has been available to date on the long-term behavior of nitinol (nickel-titanium alloy) urethral stents. In the present study, prostheses of this type were implanted in 18 German shepherd dogs in order to evaluate the reaction of the mucosa, muscles and periurethral tissue. Follow-up examinations performed after 1 week, and 1, 3, 6, 12 and 18 months included urine, macroscopic, radiologic, histologic and scanning electron microscopic analyses. Despite the excellent biocompatibility of the material, with no evidence of foreign body reactions or corrosion, there were no complete incorporations of the stent by epithelialization. Clinical application therefore appears to be problematic.
Conventional amphotericin B (Amph-B) is the drug of choice for treating systemic fungal infections. Recently, a new formulation has become available, encapsulated in liposomes (Amph-lip). This new form of administration was developed in order to lower the acute side effects and to offer the possibility of administering high doses of amphotericin B. Experience with Amph-lip is limited, especially in children. We treated four children with documented systemic fungal infections with Amph-lip and administered it empirically to 12 children. Fifteen of these 16 children were severely granulocytopenic oncologic patients. One 3-month-old baby suffered from systemic candidiasis. Amph-lip was preferred to conventional Amph-B in children with organ dysfunction developing as a consequence of conventional chemotherapy or bone marrow transplantation, after failure of conventional Amph-B to improve a fungal infection, and after adverse drug reactions had occurred. The daily doses of Amph-lip ranged from 1 to 6 mg/kg (median 3 mg/kg), the cumulative doses from 13 to 311 mg/kg (median 75 mg/kg). Acute adverse reactions or organ function abnormalities attributable to Amph-lip did not occur in 402 administrations. Amph-lip has proven to be well tolerated by children in terms of acute toxicity and in the long term. Although large cumulative doses were given, organ function abnormalities attributable to Amph-lip doses were not detected in any of ten long-term survivors over a median observation time of 36 months (range 30-44 months). Amph-lip appears to be a promising alternative antifungal treatment, especially for patients with impaired organ function, when high doses of amphotericin B are necessary.
BACKGROUND: Grass pollens, such as pollen from timothy grass (Phleum pratense), represent a major cause of type I allergy. OBJECTIVE: In this report we attempted to determine how cross-reactive allergenic components of grass pollens from different species can be represented by a minimum number of recombinant allergens. METHODS: We isolated and sequenced a timothy grass pollen cDNA coding for the major allergen Phl p I. A recombinant Phl p I-beta-galactosidase fusion protein, which bound to IgE in 87% of patients with grass pollen allergy, was produced in Escherichia coli. Using recombinant Phl p V and Phl p I, we defined representative patients' sera that bound to group I but not to group V allergens, as well as sera with reactivity against group I and group V allergens. IgE immunoblot inhibition studies were done with nitrocellulose-blotted pollen extracts from eight grass species with different geographic distribution. RESULTS: Preadsorption of patients' sera with recombinant nonfusion Phl p I strongly reduced IgE binding to group I allergens from the eight grasses, showing extensive cross-reactivity between species. CONCLUSION: A single recombinant group I allergen contains many of the IgE epitopes of group I isoallergens from a number of different grass species.