Feeding Immunity: Physiological and Behavioral Responses to Infection and Resource Limitation
Budischak, S.A.; Hansen, C.B.; Caudron, Q.; Garnier, R.; Kartzinel, T.R.; Pelczer, I.; Cressler, C.E.; van Leeuwen, A.; Graham, A.L. (2018). Feeding Immunity: Physiological and Behavioral Responses to Infection and Resource Limitation. Frontiers in Immunology 8: 1914. https://dx.doi.org/10.3389/fimmu.2017.01914
In: Frontiers in Immunology. Frontiers Research Foundation: Lausanne. e-ISSN 1664-3224, more
|   |
| Keyword |
|
| Author keywords |
Trichuris muris; resource–immune trade-offs; compensatory feeding; DNA metabarcoding; nuclear magnetic resonance spectroscopy metabolite profiling; rewilding mice |
| Authors | | Top |
- Budischak, S.A.
- Hansen, C.B.
- Caudron, Q.
|
- Garnier, R.
- Kartzinel, T.R.
- Pelczer, I.
|
- Cressler, C.E.
- van Leeuwen, A., more
- Graham, A.L.
|
| Abstract |
Resources are a core currency of species interactions and ecology in general (e.g., thinkof food webs or competition). Within parasite-infected hosts, resources are dividedamong the competing demands of host immunity and growth as well as parasitereproduction and growth. Effects of resources on immune responses are increasinglyunderstood at the cellular level (e.g., metabolic predictors of effector function), butthere has been limited consideration of how these effects scale up to affect individualenergetic regimes (e.g., allocation trade-offs), susceptibility to infection, and feedingbehavior (e.g., responses to local resource quality and quantity). We experimentallyrewilded laboratory mice (strain C57BL/6) in semi-natural enclosures to investigatethe effects of dietary protein and gastrointestinal nematode (Trichuris muris) infectionon individual-level immunity, activity, and behavior. The scale and realism of this fieldexperiment, as well as the multiple physiological assays developed for laboratory mice,enabled us to detect costs, trade-offs, and potential compensatory mechanisms thatmice employ to battle infection under different resource conditions. We found that miceon a low-protein diet spent more time feeding, which led to higher body fat stores(i.e., concentration of a satiety hormone, leptin) and altered metabolite profiles, butwhich did not fully compensate for the effects of poor nutrition on albumin or immunedefenses. Specifically, immune defenses measured as interleukin 13 (IL13) (a primarycytokine coordinating defense against T. muris) and as T. muris-specific IgG1 titerswere lower in mice on the low-protein diet. However, these reduced defenses did notresult in higher worm counts in mice with poorer diets. The lab mice, living outside forthe first time in thousands of generations, also consumed at least 26 wild plant speciesoccurring in the enclosures, and DNA metabarcoding revealed that the consumption ofdifferent wild foods may be associated with differences in leptin concentrations. Whenindividual foraging behavior was accounted for, worm infection significantly reducedrates of host weight gain. Housing laboratory mice in outdoor enclosures provided newinsights into the resource costs of immune defense to helminth infection and how hostsmodify their behavior to compensate for those costs. |
|
