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Background IgE‐epitope profiling can accurately diagnose clinical peanut allergy. Objective We sought to determine whether sequential (linear) epitope‐specific IgE (ses‐IgE) profiling can provide probabilities of tolerating discrete doses of peanut protein in allergic subjects undergoing double‐blind, placebo‐controlled food challenges utilizing PRACTALL dosing. Methods Sixty four ses‐IgE antibodies were quantified in blood samples using a bead‐based epitope assay. A pair of ses‐IgEs that predicts Cumulative Tolerated Dose (CTD) was determined using regression in 75 subjects from the discovery cohort. This epitope‐based predictor was validated on 331 subjects from five independent cohorts (ages 4–25 years). Subjects were grouped based on their predicted values and probabilities of reactions at each CTD threshold were calculated. Results In discovery, an algorithm using two ses‐IgE antibodies was correlated with CTDs (rho = 0.61, p < .05); this correlation was 0.51 (p < .05) in validation. Using the ses‐IgE‐based predictor, subjects were assigned into “high,” “moderate,” or “low” dose‐reactivity groups. On average, subjects in the “high” group were four times more likely to tolerate a specific dose, compared with the “low” group. For example, predicted probabilities of tolerating 4, 14, 44, and 144 or 444 mg in the “low” group were 92%, 77%, 53%, 29%, and 10% compared with 98%, 95%, 94%, 88%, and 73% in the “high” group. Conclusions Accurate predictions of food challenge thresholds are complex due to factors including limited responder sample sizes at each dose and variations in study‐specific challenge protocols. Despite these limitations, an epitope‐based predictor was able to accurately identify CTDs and may provide a useful surrogate for peanut challenges.

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Observations from 1974-2016 of Caribou (Rangifer tarandus) on the archipelago that comprises Slate Islands Provincial Park allowed us to infer direct and indirect effects of the arrival of Wolf (Canis lupus) pairs in winters of 1993-94 and 2003-04. Wolves created conditions that led to the near demise of Caribou from the islands, including some, but not all, behavioural changes in Caribou consistent with avoiding predators. Caribou on SIPP did not appear to return to calving locations near shoreline areas, nor use them to escape from Wolves by entering water. Shorelines and locations of Patterson Island near a Wolf-occupied Red Fox (Vulpes vulpes) den were the most common Caribou kill locations. Wolves also functionally shifted the ecosystem in Slate Islands Provincial Park via direct and indirect effects on North American Beavers (Castor canadensis), Red Foxes and Snowshoe Hares (Lepus americanus).