de la Fuente et al.
The alpha-Gal syndrome: new insights into the tick-host conflict and cooperation
Parasit. Vectors 2019, 12:154, doi.org/10.1186/s13071-019-3413-z
Many animals, including mammals, amphibians, mollusks, as well as ticks consist of the enzyme α -1-3- galactosyltransferase and can synthesize the galactose-based oligosaccharide Gal α 1-3Gal β 1-(3)4GlcNAc-R (Gal) (α Gal). However, humans (like birds and fish) cannot produce α Gal and therefore, α Gal can trigger an immune response, as well as IgE antibodies and an allergic disease – the alpha Gal syndrome. Ticks bites can induce high levels of anti αGal IgG antibodies that mediate delayed anaphylaxis to red meat consumption, and immediate anaphylaxis to tick bites, xenotransplantation and certain drugs such as cetuximab. The alpha-Gal syndrome is becoming a global problem. Most patients that had become allergic, had tolerated red meat for many years before being sensitized by tick bites. While in the past, the negative effects of the α Gal immune response was in focus, the authors discuss here possible benefits of the α Gal immune response. The anti α Gal immune response may help protect against certain pathogens, e.g. Mycobacterium, Trypanosoma, Borrelia, Leishmania.
In this context, vaccines may be developed against pathogens carrying α Gal epitopes and recently, it could be shown that e.g. an α Gal based glycovaccine can protect against the murine acute Chagas disease (Portillo et al. npj Vaccines 2019, 4:13).