The alpha-gal story: Lessons learned from connecting the dots

Abstract

Anaphylaxis is a severe allergic reaction that can be rapidly progressing and fatal; thus, establishing the etiology of anaphylaxis is pivotal to long-term risk management. Our recent work has identified a novel IgE antibody response to a mammalian oligosaccharide epitope, galactosealpha-1,3-galactose (alpha-gal). IgE to alpha-gal has been associated with two distinct forms of anaphylaxis: i) immediate onset anaphylaxis during first exposure to intravenous cetuximab, and ii) delayed onset anaphylaxis 3-6 hours after ingestion of mammalian food products (e.g., beef and pork). Results of our studies and those of others strongly suggest that tick bites are a cause, if not the only significant cause, of IgE antibody responses to alpha-gal in the southern, eastern and central United States, Europe, Australia and parts of Asia. Typical immune responses to carbohydrates are considered to be T cell-independent, while IgE antibody production is thought to involve sequential class-switching that requires input from T cells. Therefore, establishing the mechanism of the specific IgE antibody response to alpha-gal will be an important aspect to address as this area of research continues.

Alpha-Gal Syndrome in Children: Peculiarities of a “Tick-Borne” Allergic Disease

“…A detailed chronology of scientific discoveries about AGS starts in 1989, when Mrs. Sandra Latimer and Dr. Antony Deutsch ( 9 ) reported in Georgia (USA) the first case reports of delayed red meat allergy with a possible correlation to tick bites. In 2007, Van Nunen et al ( 10 ) reported an Australian case series of delayed red meat allergy, with patients recalling I. holocyclus tick bites before symptom onset and having positive prick test or specific IgE to red meat.…”