Significance of Rubber Elongation Factor as a Latex Allergen

Abstract

IgE-mediated hypersensitivity to proteins eluting from surgical gloves and other natural rubber products is a well-recognized allergic condition with special impact to health care workers and sensitized patients. Since rubber elongation factor (REF) has been suggested to be the major latex allergen (Hev b 1) we purified REF from rubber particles using electrophoresis and electroelution and reevaluated the occurrence of IgE antibodies to purified REF. The purified protein was subjected to tryptic digestion, peptide separation and amino acid sequencing. Amino acid sequences of 9 tryptic peptides from the purified 14-kD protein gave 100% homology to REF. In immunoblotting, sera from 4 of 6 latex-allergic children with spina bifida or other congenital anomalies exhibited IgE antibodies against REF whereas only 1 serum from the 30 other latex-allergic patients had similar antibodies. In IgE ELISA 8/45 (18%) latex-allergic patients had IgE antibodies to purified REF, whereas 30 (67%) of the same patients had IgE antibodies to purified prohevein, another rubber protein, recently shown to be a major natural rubber latex allergen. The observed overall low frequency of IgE antibodies to purified REF, as measured by two specific IgE assays, indicates that REF is one but not the most significant allergen among the natural rubber latex proteins.

Identification and Cloning of Prs a 1, a 32-kDa Endochitinase and Major Allergen of Avocado, and Its Expression in the Yeast Pichia pastoris

“…4A). As expected, the inhibition is only partial, because the 14-kDa C-terminal domain of prohevein still binds IgE from 30% of latex-allergic patients' sera (30). Additional evidence for the cross-reactivity between Prs a 1 and the 20-kDa allergen from latex is provided by the observation of two patients whose IgE recognized exclusively prohevein in natural latex B fraction; IgE from sera of these patients bound exclusively to the 32-kDa Prs a 1 in avocado extracts.…”

“…The antisense oligonucleotide was the lock-docking oligo(dT) primer 5Ј-(T) 30 (G/A/C)(G/A/C/T)-3Ј. The PCR products were cloned into pCRII (TA Cloning kit, Invitrogen, San Diego, CA) and sequenced.…”

“…Assay mixtures contained 12 l of 5ϫ potato dextrose broth (Difco), 3000 spores of the test fungus in 10 l of water, and 38 l of the rPrs a 1 solution. The effect of rPrs a 1 was tested at concentrations of 1,5,10,15,20,25,30,35,40,50, and 100 g/ml. In the controls, heat-denatured rPrs a 1 and sterile water were used instead of the solution containing the enzyme.…”

Natural rubber latex allergy

“…Latex RAST seems to detect well highly allergic patients although one study reported anaphylactic reactions in NRL-allergic patients with negative RAST (59). IgE antibodies to purified NRL allergens such as hevein have also been measured by ELISA methods that show 100% specificity (32,60). Their use is currently restricted to scientific purposes, but, when appropriate mixtures of purified allergens are available, such reagents can provide exquisitely specific and sensitive means of in vitro diagnosis of NRL allergy.…”

The Major Conformational IgE-binding Epitopes of Hevein (Hev b6.02) Are Identified by a Novel Chimera-based Allergen Epitope Mapping Strategy

“…Hevein has been found to elute in large quantities from NRL products (5). The importance of hevein as a latex allergen is supported by the findings that Ͼ70% of latexallergic patients have hevein IgE antibodies (6) and that hevein elicits positive skin prick test reactions in the great majority of latex-allergic patients (1). Hevein is therefore a useful tool in the diagnosis of latex allergy as well as a potential candidate for immunotherapy.…”