(Ai) The 29 serum samples were tested for IT50s with the challenge strain H. pylori BCM300. Only one individual (no. 1027) showed no induction of IT50, whereas four individuals demonstrated pre-challenge titers (blue). (Aii) The unrelated strain 17875/Le identified five serum samples with bbAbs reaching the risk factor IT50 = 30 (dotted line), ranging from an IT50 of 27 to 85, with a mean IT50 of 49 and a median IT50 of 50 (Table S1A).
(B) Five SPF rhesus macaques were challenge infected with H. pylori J166. Two out of the five SPF animals, no. 2 and no. 3, demonstrated induction of an IT50 response, whereas the other three animals demonstrated high pre-challenge IT50 titers (in blue) as tested with J166 (Bi) and 17875/Leb (Figure S1A)
(Bii) Testing of the serum samples from the two animals no. 2 and no. 3 with the phylogenetically distant (unrelated) Indian strain I9 showed that they also induced IT50 responses of bbAbs (Tables S1B and S1C). ND - Not Determined