Fig. 7. Reactivity of synthetic analogs with naturally infected human and mouse sera.

(Top left) Reactivity (z-score, y-axis) of natural OspC variants (n = 16) and evolutionary analogs (n = 6) (x-axis) with sera from naturally infected P. leucopus mice (n = 10). All six evolutionary analogs showed significantly higher (with t tests) reactivity with the sera of the reservoir host species than the reactivity of the natural variants as a group. (Top right) Antigen reaction characteristics (ARC) curves showed consistently high reactivity of the six evolutionary analogs, indicating their broader antigenicity relative to the natural OspC variants in reacting with the sera of the reservoir hosts of B. burgdorferi. (Bottom left and right) Corresponding graphs with sera from naturally infected human patients (n = 41). Three centroids (CT2, CT3, and CT4) showed significantly higher (with t tests) reactivity than the reactivity of the natural variants as a group. Reactivity of the other three evolutionary analogs (CT1, Consense, and Root) was significantly lower than or not significantly different from the reactivity of the natural antigen variants.