Meat allergy associated with galactosyl-α-(1,3)-galactose (α-Gal)-Closing diagnostic gaps by anti-α-Gal IgE immune profiling.

BACKGROUND: Glycoproteins and glycolipids of some mammalian species contain the disaccharide galactosyl-α-(1,3)-galactose (α-Gal). It is known that α-Gal is immunogenic in humans and causes glycan-specific IgG and also IgE responses with clinical relevance. α-Gal is part of the IgE-reactive monoclonal therapeutic antibody cetuximab (CTX) and is associated with delayed anaphylaxis to red meat. In this study, different α-Gal-containing analytes are examined in singleplex and multiplex assays to resolve individual sensitization patterns with IgE against α-Gal. METHODS: Three serum groups, α-Gal-associated meat allergy (MA) patients, idiopathic anaphylaxis (IA) patients with suspected MA, and non-meat-allergic healthy control individuals (HC), were analyzed via singleplex allergy diagnostics and a newly established immunoblot diagnostic system. The new dot blot detection system resolved individual IgE sensitization profiles for α-Gal-containing analytes CTX, bovine thyroglobulin (Bos d TG), and human serum albumin (HSA)-conjugated α-Gal. RESULTS: Singleplex allergy diagnostics using the α-Gal analytes CTX and Bos d TG confirms the history of MA patients in 91% and 88% of the cases, respectively. A novel dot blot-based assay system for the detection of IgE against α-Gal reveals individual IgE sensitization profiles for α-Gal-containing analytes. An α-Gal-associated IgE cross-reactivity profile (IgE against CTX, Bos d TG, and HSA-α-Gal) was identified, which is associated with MA. CONCLUSIONS: Detection of individual sensitization patterns with different α-Gal-containing analytes provides the basis for an individual allergy diagnosis for α-Gal-sensitized patients. Higher amounts of α-Gal in pork and beef innards compared to muscle meat as indicated by a higher staining intensity are a plausible explanation for the difference in allergic symptom severity.

[Delayed type allergic reaction to red azo dye in tattooing]. / Allergische Spättypreaktion auf roten Azofarbstoff in Tätowierungen.

Allergic reactions in tattoos are comparatively rare. In most cases the reactions are caused by different red pigments. While in the past these reactions have been ascribed to mercury salts (cinnebar) and cadmium sulphide, now synthetic inorganic azo dyes have also been found to be responsible for such reactions. A 42-year-old man presented with an allergic reaction in the red parts of his tattoos. Histologically a chronic granulomatous, partly fibrous inflammation with transfollicular elimination of pigment granules was found. Spontaneous regression in a part of the inflammatory reaction was observed, simultaneously with depigmentation and scarring of the overlying skin. The pigment used for tattooing was found to be an aromatic azo derivative. In addition to a positive cutaneous reaction to the dye, the patient also showed a positive patch test to Napthol AS, used for the coupling of different dyes in the textile industry.