Cross-reactivity among ants
There is substantial cross-reactivity between different fire ant species due to the high similarity of their major allergens PLA1 (Sol i 1) and antigen 5 (Sol i 3). The less conserved minor allergens Sol i 2 and Sol i 4 may harbor species-specific epitopes.61 Strong cross-reactivity has also been reported between differentBrachyponera species.62 In contrast, cross-reactivity within the genus Myrmecia is heterogeneous and monosensitization to single species appears to be common.29,63
Data concerning cross-reactivity between different ant genera are scarce and controversial. SI is low between known ant venom phospholipases (30-35%), while it is 50-60% for antigens 5 from Solenopsis(Sol i 3), Brachyponera (Pac c 3), and Dinoponera . Strong cross-reactivity between Solenopsis invicta andBrachyponera sennaarensis (samsum ant), essentially due to antigen 5, has been reported in one study64, whereas no cross-reactivity was observed between Solenopsis andBrachyponera chinensis in another study.62Preliminary data revealed no evidence for cross-reactivity betweenMyrmecia and fire ant venom65 which is consistent with the lack of antigen 5, PLA1, and Sol i 2/4-like proteins in Myrmecia venom.66