Birch and Oak tree pollen allergy and PR-10 proteins
PR10 allergens are present in multiple species of deciduous trees pollen. Among them, birch in Europe49 and oak in North America are regarded as primary sensitizers. There are products, registered worldwide for the treatment of birch pollen allergy50. Recent data suggest that a birch-based vaccine has clinical benefit during oak pollen season in North America 51. Interestingly, a study analyzed the effect of birch-based AIT in cross-reactive T cell response to homologous PR10 allergens from other trees 52. This study demonstrated that down-regulation of T cell reactivity can be achieved against multiple, T cell cross-reactive PR-10 molecules. The control of T cell proliferation based on T cell cross-reactivity might be the most relevant endpoint for successful AIT. As in the case of profilins, PR10 proteins are also present in multiple vegetable species, leading to the concept of a PR10 allergy syndrome. There is very limited evidence on the clinical benefit of PR10 based pollen AIT in the amelioration of pollen-related food allergy syndrome (FPAS)53,54. However, immunotherapy with Mal d 1 has been associated with clinical improvement 55. More studies will be needed to clarify potential use of PR10 pollen vaccines in this particular type of food allergy.