Recombinant allergens for diagnosis of allergic bronchopulmonary aspergillosis

PURPOSE: The investigation aimed at assessing the prevalence of depression among residents in a nursing home. METHODS: In a rural area of Germany a representative sample was examined by means of the "Brief Assessment Interview" (BAI). RESULTS: 17% had a depressive disorder without dementia, 9% had a mild dementia syndrome and a depressive disorder; a total of 47% suffered from symptoms of dementia without depression. Most of the patients were treated by general practitioners or internists. 11% of the patients with depression were treated with antidepressants, 19% with neuroleptics, 17% with minor tranquillizers, and 17% with hypnotics. Only 20% of the depressive patients had ever been examined by a psychiatrist, 4% underwent an actual psychiatric therapy. CONCLUSION: Elderly patients with depressive disorders living in nursing homes need a more specific psychiatric treatment.     

Masked and labelled food allergens

Several food proteins are used as food additives or may be contained in foods as contaminants. These masked allergens are at high risk of inducing severe clinical reactions: acute asthma, laryngeal angioedema, anaphylactic shock or even death. The present regulation requires labelling only if the level of food ingredients is superior to 25% of the final product. Several immunologic methods can detect low levels of proteins, equal or inferior to 2%. However a level of 1% or less may be noxious, suggesting a need for a specific line of food products which could be guaranteed free of ... and which might be recommended to patients with food allergy.     

Prenatal contact with inhalant allergens

Bilirubin is oxidized by brain mitochondrial membranes at a rate which may contribute significantly to clearance of bilirubin from brain. Different strains of congenitally jaundiced rats (Gunn rats) vary widely as far as the mortality rate of the homozygous (jaundiced) pups. Because the ability to oxidize bilirubin in brain may protect against toxicity, we hypothesized that the ability to oxidize bilirubin would be lower in Gunn rat strains (ACI/N-j) with a high mortality rate in the homozygous pups. Mitochondria were obtained from young rat brains by differential centrifugation in sucrose gradients. The mitochondria were ruptured by sonication. The change in optical density of a bilirubin solution at 440 nm was measured over time following addition of the membrane suspension. The rate of bilirubin oxidation was significantly lower in rats of the RHA/N-j strain both at 7-8 days of age and in adults, compared to rats of the ACI/N-j and the Sprague-Dawley strains at the same age points. Differences in mortality rates between the RHA/N-j and the ACI/N-j strains of Gunn rats could not be explained on the basis of differences in the ability of brain mitochondrial membranes to oxidize bilirubin, as these activities were lower in the RHA/N-j rats, which also have lower mortality rates, but higher in the ACI/N-j rats, which have remarkably high mortality rates. This study also confirmed previous findings relative to age maturation of the enzyme activity.     

IgE-mediated allergy from vegetable allergens

Allergy to fresh fruits and vegetables is IgE-mediated. Its main clinical features are local, such as oral pruritus and swelling of lips and tongue but systemic symptoms such as urticaria, asthma, or anaphylactic shock may occur. Clinical associations with allergic rhinitis due to cross-reactive antigens of pollens and foods are frequent.     

Characterized allergens causing bakers'' asthma

OBJECTIVE: Surveillance after orchiectomy alone becomes popular for the management of clinical stage I nonseminomatous germ cell testicular tumours (CS I NSGCTT). Effort to identify patients at high risk of relapse leads to searching prognostic factors of CS I NSGCTT. The aim of this study was to identify those patients in whom a surveillance policy is less likely to be successful. PATIENTS AND RESULTS: Seventy-two CS I NSGCTT patients were stratified to different risk-adapted therapeutic approaches according to histopathologic findings of primary tumor removed by inguinal orchiectomy. Eighteen patients (group A) with vascular invasion and majority of embryonal carcinoma component in the primary tumor were treated with adjuvant BEP chemotherapy. None of them experienced disease progression after a median follow-up period of 36 months after orchiectomy. Five patients (group B) with vascular invasion and the majority of teratomatous elements in the primary tumor have been followed up 56 months after orchiectomy. They were treated with primary retroperitoneal lymph node dissection (RPLND). Two of them (40%) had pathologic stage II after RPLND and underwent subsequent chemotherapy. One of them died due to disease progression 29 months following orchiectomy. Another one lives with no evidence of disease (NED). Three patients in pathologic stage I are alive with NED. Forth-nine patients (group C) without vascular invasion have been followed up for a median duration of 37 months after orchiectomy. They were kept under close surveillance, consisted of regular follow-up with tumor markers, chest x-ray and CT of the retroperitoneum. Disease progression was observed in 7 (14.3%) patients after a median duration of 8 months after orchiectomy. They were treated with BEP chemotherapy and live with disease-free median survival of 22 months after completion of therapy. The overall survival rate of all 72 patients was 98.6%. The median survival for all patients was 37 months (range 7-73). CONCLUSIONS: The authors will continue to use surveillance policy only in patients without vascular invasion in the primary tumor.     

New allergens and pediatric allergology

The first manifestation of allergies most often occurs in childhood. Prevention of atopic diseases is one of the very important tasks in pediatrics. Exact knowledge of allergens and the role of adjuvant factors in allergic sensitisation is necessary to define measures for allergy prevention aiming at a reduction of the worldwide increasing prevalence of atopic diseases. Indoor allergens and tobacco smoke exposure are risk factors for early sensitisation and asthma. In addition to house dust mites there are other indoor allergens like moulds, pet allergens, cockroaches and many more. Exact diagnosis and identification of the causative allergen allows therapy directing towards allergen avoidance and relieving symptoms without need of any additional pharmaceutical treatment. This cost-saving strategy helps to prevent disease-related long absences from school and work. Exact knowledge of the structure and biology of the etiologic allergens is a prerequisite for this treatment strategy. We review the great contribution of the Allergy Unit in Zurich to the identification and characterisation of environmental allergens.     

Nonspecific binding of IgE to allergens

Nonspecific IgE binding to allergens was observed in testing myeloma IgEs, namely, IgE-VL and IgE-PS, chimeric IgE (IgE-JW8), and the recombinant IgE Fc epsilon peptide CH1-CH4, in two different immunoassays. This binding was concentration-dependent but detectable only at higher IgE concentration. In RAST inhibition, IgE-allergen interactions could be reduced by using either matching or nonmatching allergens. In order to test whether the nonspecific binding of IgE to allergens was due to carbohydrate interaction, myeloma IgEs and the chimeric IgE were desialized with neuraminidase. Desialized samples were equally well recognized by xenogenic antibodies as native IgEs, but binding of IgE to Fc epsilon receptors on basophils was affected by the treatment, as shown in the histamine-release assay. Desialization of IgE affected also its binding capacity to allergens in RAST: binding of chimeric IgE was reduced, but nonspecific binding of myeloma IgE-VL was enhanced. Hence, nonspecific allergen-IgE binding may be partly due to a lectin-like interaction, but may depend mostly on the tertiary structure of IgE. Thus, nonspecific IgE-allergen interactions might present a problem 1) at high IgE concentration, and 2) depend on the grade of sialization of IgE, which might affect its conformation. This may explain why patients with elevated total IgE levels often have multiple weak positive RASTs with non-cross-reactive allergens.     

Recombinant coagulation factors

Sometimes, preoperative planning in dental implantology, based on sufficient alveolar height, cannot be verified due to transversal deficiencies. A total of 102 bony mandibles and 95 maxillae were analysed after classification of atrophy, simulating implant insertion at 518 standardised edentulous cross sections with regard to anterior/posterior, mandible/maxilla and class of atrophy. Furthermore, the relation of alveolar height to possible implant length in 86 patients was evaluated retrospectively. Implant length reduction compared with alveolar height was necessary in 10% (mandibles) and 7.5% (maxillae) of the bony-jaw sections and 52.5% (mandibles) and 41.5% (maxillae) of the patients' implant regions. In this respect, the class of atrophy of the bony jaws was more important than the region of simulation. However, the highest differences were observed between mandibles and maxillae, both clinically and experimentally: simulation was possible in all mandibles and 42.5% of the maxillae, but clinical implantation was only possible in 86% of 62 mandibles and 0% of 24 maxillae, mostly due to reduced alveolar height. Alveolar ridge width primarily affected the possible implant lengths. Nevertheless, in four (two mandibular and two maxillary cases) of 58 patients (7%) with sufficient height, a surgical procedure that had already been started had to be stopped. It is expected that cross-sectional radiographical techniques of implantation planning, including ridge-width determination, will gain importance in the future.     

Latex allergens: review of current knowledge

Both health care workers and spina bifida patients are at risk to develop type I latex allergy since allergenic proteins of natural rubber latex are present in a variety of latex products. Natural latex contains more than 250 polypeptides and approximately 60 of them show IgE-binding characteristics. A multitude of these latex allergens has been identified, and their sensitization potency for both risk groups has been determined. While hevein (Hev b 6.02) is the major allergen in latex-allergic health care workers, 80% of latex sensitized-spina bifida children have IgE antibodies to the "rubber elongation factor" (Hev b 1). Almost all relevant latex allergens have been identified in natural latex products: however, no data on the allergen profiles of individual latex products exist. The knowledge of the major latex allergens enables improved diagnosis and to monitor the success of prevention strategies for decreasing the high prevalence of latex allergies.     

Filtration of airborne allergens in various households

The filtration system investigated in this study uses the thermic convection caused by radiators for the adsorption of airborne particles. The effect of this filtration system on the reduction of clinical symptoms of allergic bronchial asthma was tested as well as its capability in retaining airborne allergens, in particular those of the house dust mite Dermatophagoides pteronyssinus (D. pter.), which are responsible for this special kind of asthma. Dust samples were taken before and after the heating season in households of 36 persons with D. pter. caused asthma. Their mite content was investigated using mite flotation and direct microscopy, their guanine content using the Acarex-test. An allergen extract obtained from the filters was tested on its allergen content by RAST-inhibition. It could be observed that compared to the preceding heating season 55% of the volunteers felt an improvement of their asthmatic symptoms. It was possible to extract allergens of D. pteronyssinus, house dust and mould from the filters. All these results show the capability of the filters to adsorb house dust mite (HDM) allergens.     

Immunoaffinity analysis of cross-reacting allergens by protein blotting

IgE antibodies from sera having reactivity against ryegrass pollen protein allergens, wheat endosperm protein allergens and also several other cereal protein allergens were adsorbed with either ryegrass pollen or the wheat/globulin fraction immobilised on solid phases and subsequently eluted with low pH buffer. The eluted antibodies were reacted with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) blots of the different allergens. Antibodies adsorbed and subsequently eluted from the two allergen sources recognised different spectra of proteins in the ryegrass pollen and cereal allergen sources and indicated the degree of immunological cross-reactivity. Intra-species cross-reactivity of IgE antibodies was demonstrated employing similar methods to those used for the pollen and cereal allergens by using a recombinant allergen from the venom of the ant Myrmecia pilosula as the immunoadsorbent protein on the solid phase.     

Cross-reacting allergens in natural rubber latex and avocado

Although phencyclidine (PCP) has several neurochemical effects, the most pharmacologically relevant are thought to be its ability to antagonize the activity of N-methyl-D-aspartate (NMDA)-type glutamate receptors and to increase extracellular dopamine concentrations. In order to elucidate the nature and consequence of PCP actions on glutamatergic and dopaminergic pathways, this study examined the response of extrapyramidal and limbic neurotensin systems to this drug. Multiple, but not single, doses of PCP caused increases in striatal neurotensin-like immunoreactivity content of 150-200% of control. These effects were blocked by the dopamine D1 receptor antagonist, SCH 23390, suggesting they were caused by PCP-mediated enhanced dopamine activity at dopamine D1 receptors. In contrast, MK-801 (dizocilpine), a selective NMDA receptor antagonist that acts at the same site as PCP, had no effect on neurotensin-like immunoreactivity content when given alone. In addition, coadministration of MK-801 with PCP did not alter the effect of PCP on striatal neurotensin-like immunoreactivity content. This lack of effect suggests that the actions of PCP on NMDA receptors was not involved in the neurotensin response. The PCP effect on neurotensin striatal pathways also appeared not to be associated with the dopamine D2 or gamma-aminobutyric acid (GABA) systems: a possible role for the sigma receptor in this effect could not be eliminated. Administration of multiple doses of PCP also affected neurotensin-like immunoreactivity content in the nucleus accumbens (160% compared to control) and frontal cortex (40% compared to control), but not the substantia nigra. The neurotensin effects of PCP are compared to those of another psychotomimetic drug of abuse, methamphetamine.     

Latex allergens in tire dust and airborne particles

The prevalence and severity of latex allergy has increased dramatically in the last 15 years due to exposure to natural rubber products. Although historically this health risk has been elevated in hospital personnel and patients, a recent survey has indicated a significant potential risk for the general population. To obtain a wide-spread source for latex exposure, we have considered tire debris. We have searched for the presence of latex allergens in passenger car and truck tire tread, in debris deposited from the atmosphere near a freeway, and in airborne particulate matter samples representative of the entire year 1993 at two sites in the Los Angeles basin (California). After extraction of the samples with phosphate buffered saline, a modified-ELISA inhibition assay was used to measure relative allergen potency and Western blot analyses were used to identify latex allergens. The inhibition studies with the human IgE latex assay revealed inhibition by the tire tread source samples and ambient freeway dust, as well as by control latex sap and latex glove extracts. Levels of extractable latex allergen per unit of protein extracted were about two orders of magnitude lower for tire tread as compared to latex gloves. Western blot analyses using binding of human IgE from latex-sensitive patients showed a band at 34-36 kDa in all tire and ambient samples. Long Beach and Los Angeles, California, air samples showed four additional bands between 50 and 135 kDa. Alternative Western blot analyses using rabbit IgG raised against latex proteins showed a broad band at 30-50 kDa in all samples, with additional bands in the urban air samples similar to the IgE results. A latex cross-reactive material was identified in mountain cedar. In conclusion, the latex allergens or latex cross-reactive material present in sedimented and airborne particulate material, derived from tire debris, and generated by heavy urban vehicle traffic could be important factors in producing latex allergy and asthma symptoms associated with air pollution particles.