Sllmmal~Type I allergy is a major health problem in industrialized countries where up to 15% of the population suffer from allergic symptoms (rhinitis, conjunctivitis, and asthma). Previously, we identified a cDNA clone that encoded a birch pollen allergen as profilin. Profilins constitute a ubiquitous family of proteins that control actin polymerization in eukaryotic cells; in particular, profilin participates in the acrosomal reaction of animal sperm cells. Although profilins had been unknown in plants so far, our finding led to the assumption that profilins might have similar functions in pollens during plant fertilization and therefore represent allergenic components in almost all pollens. We show that profilins are prominent allergens that can be isolated from tree pollens (Betula verrucosa, birch), from pollens of grasses (Phleum pratense, timothy grass), and weeds (Artemisia vulgaris, mugwort). About 20% of all pollen allergic patients tested (n = 65) displayed immunoglobulin E (IgE) reactivity to recombinant birch prolilin that was expressed in pKK223-3. An IgE inhibition experiment performed with recombinant birch profilin and purified natural profilins from timothy grass and mugwort indicates common IgE epitopes. Moreover, all pollen profilins purified from these far distantly related plant species, and likewise the purified recombinant birch profilin, are able to elicit dose-dependent histamine release via high affinity Fce receptor of blood basophils from profilin allergic patients. The presence of profdin and possibly related proteins as crossreacting allergenic components in various plants therefore provides an explanation as to why certain allergic patients display type I allergic reactions with pollens and even food from distantly related plants. A functional pan-allergen, like profilin, available as purified recombinant protein, may be a useful diagnostic and probably therapeutic reagent.

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The purification of a 15 kD allergen from celery was obtained by a four step procedure. Evidence for at least two isoallergenic forms was obtained after analysis by two-dimensional-electrophoresis. A rabbit polyclonal antibody raised against this purified allergen allowed us to confirm our precedent results on the occurrence of allergenically and molecular mass-related components in celery and birch and mugwort pollens. In addition such components were also present in numerous other species like Cynodon dactylon, Sorghum halopense, Poa pratensis, Ambrosia elatior and in apple and carrot. The 15 kD allergen was identified as profilin by use of a specific rabbit polyclonal antibody that recognized a recombinant birch profilin. In addition, the purified celery allergen binds IgE from sera of patients allergic to birch profilin. These results reinforce the concept of profilin as a panallergen responsible in some patients for cross-allergic manifestations to various and unrelated species of grasses, weeds, trees, vegetables and fruits.

Considering the high occurrence of profilin as an allergen in many plant species, the assumption was made that profilin might be an allergen in Hevea brasiliensis, a member of the latex producing Euphorbiaceae family. Using IgE-binding inhibition by purified profilins we demonstrated that profilin is an IgE-binding component in the cytosolic fraction of natural latex and, to a lower extent, in the rubber fraction. Thirty-five out of 36 sera containing IgE to ragweed-profilin reacted with profilin from latex, indicating structural homologies between profilins from latex and ragweed. A large percentage (59%) of these sera were found to be positive in CAP latex assay. The preincubation of these sera with purified ragweed profilin greatly inhibited the CAP latex. Because profilin is also present in banana extract, it is likely to be involved in cross-sensitivity to banana and latex. In a group of 19 individuals allergic to latex only two had anti-profilin IgE antibodies. Profilin was barely detectable on glove extract immunoblots, whereas some sera from patients allergic to latex reacted with a 15 kDa allergen which was not profilin. Consequently, IgE antibodies to latex-profilin is a questionable factor for sensitization of occupationally-exposed patients; however, sensitization to profilin should be taken into account when interpreting the results of latex IgE antibody assays.

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Summary Sixty‐one sera with positive RAST to mugwort pollen (Artemisiae vulgaris) were submitted to RASTs for birch pollen (Betula verrucosa) and celery (Apium graveolens). In 36 cases RAST results were positive for celery. In addition, 23 sera presented specific IgE to birch pollen. The binding of specific IgE to individual allergens in celery, mugwort pollen and birch pollen was studied by the immunoblotting technique. This involved electrophoretic separation of allergenic extracts, electrotransfer of proteins onto nitrocellulose sheets and sensitive immunoenzymatic detection. Eighteen sera had specific IgE binding to two celery components of molecular weight around 15 kD. All these sera also detected a 15 kD allergen in mugwort and two allergens in birch of 14 kD and 16 kD molecular weight. The sera that did not detect the 15 kD bands in celery failed to react with both the 15 kD mugwort component and the 14 and 16 kD birch components. Specific cross‐inhibitions of the detection of these allergens on immunoblots were obtained by pre‐incubation of the sera with crude extract of the three species. These results strongly suggest that such allergens display some structural identity and that they could be at the origin of some cases of crossed hypersensitivity to celery, mugwort pollen and birch pollen.

Summary. The study was designed to test further the usefulness of the radioreceptor assay of thyroid stimulating hormone (TSH) binding inhibitory immunoglobulins (TBH) and the bioassay of thyroid stimulating antibodies (TSAb) or TSH stimulated cAMP response inhibitory antibodies (TBkAb) in the prediction of neonatal thyroid dysfunction. Of 63 pregnant women with a current or past history of autoimmune thyroid disorder, 11 (one with active and six with a past history of Graves'disease and four with autoimmune thyroiditis) gave birth to a baby with transient hyper or hypo‐thyroidism. Only high maternal titres (which could persist after partial thyroidectomy) of anti TSH‐receptor antibodies (TRAb) led to neonatal hyperthyroidism. Both types of assay were able to detect the antibodies responsible for transitory neonatal autoimmune thyroid disease. TBH values reflectcd TSAb titres so that there was a significant correlation between the results of both assays in women with Graves' disease and in neonatal sera. Positive TBII and TBkAb activities were present in 5 of the 28 women with autoimmune thyroiditis. Therefore, when TBII is positive, the functional characterization of the antibodies warrants the use of the bioassay.

We report an anaphylactic reaction which occurred very shortly after ingestion of a fresh fig. The IgE-dependent mechanism was demonstrated on the basis of positivity of the prick test performed with fresh fig (Ficus carica) extract. In addition, we were able to detect specific IgE to the same extract in the serum. The patient did not demonstrate sensitization to other common allergens involved in respiratory and food allergies. However, detection of specific IgE to F. benjamina indicated a sensitization to weeping fig. The CAP F. benjamina was partially inhibited by preincubation of the serum with fig extract, suggesting that these two species of Ficus share some common allergens. In this context, the assumption can be made that weeping fig was responsible for the initial sensitization in this patient.