10.5061/DRYAD.H0D12
Stahlschmidt, Zachary R.
Dalhousie University
Acker, Madison
Dalhousie University
Kovalko, Ilya
Dalhousie University
Adamo, Shelley A.
Dalhousie University
Data from: The double-edged sword of immune defence and damage control: do
food availability and immune challenge alter the balance?
Dryad
dataset
2016
Self-damage
ecological immunology
Gryllus texensis
2016-03-24T00:00:00Z
2016-03-24T00:00:00Z
en
https://doi.org/10.1111/1365-2435.12454
56764 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1.Animal immune systems must adaptively balance aggressive immune
resistance (ability to destroy pathogens) with infection tolerance
(ability to withstand the negative effects of infection; e.g.,
immunopathology or damage due to pathogen metabolism). 2.Insects offer
unique insight into this balancing act because phenoloxidase (PO)-mediated
melanisation is a key feature of immune resistance, but PO activation
obligates the production of non-specific reactive species that can cause
self-damage. The antioxidant glutathione (GSH) can provide protection
against such reactive molecules, but high levels of GSH can impair
melanisation. In support of the hypothesis that GSH can protect insects
(e.g., crickets) from self-damage during an immune response, we found that
bacterially infected crickets showed a significant positive relationship
between GSH haemolymph concentration and fecundity after controlling for
bacterial growth rate. That is, GSH may be a mechanism of infection
tolerance because it correlated with fecundity despite bacterial
proliferation. 3.Next, we factorially manipulated food availability and
immune activation in female crickets to examine whether the relative
balance between a component of immune resistance (i.e., PO) and protection
from self-damage (i.e., GSH) was plastic and sensitive to environmental
conditions. 4.Glutathione and PO were positively correlated, and the
PO:GSH ratio was robust and not affected by food availability or immune
activation. Thus, increased investment in a mechanism of immune resistance
may obligate a concomitant increase in GSH to reduce self-damage (i.e.,
increase infection tolerance). Chronic immune activation led to greater
tolerance of oxidative stress suggesting that repeated immune activation
up-regulates infection tolerance mechanisms. Food limitation led to
reduced PO activity, but not GSH concentration. This result suggests that
mechanisms of immune resistance may be more sensitive to resource scarcity
than mechanisms of infection tolerance. 5.We demonstrate that some
mechanisms of immune resistance and infection tolerance can be correlated,
and that they can be affected by food availability or immune activation.
Raw hemolymph, egg-laying, and paraquat survival dataData from: Egg-laying
and paraquat survival data, and hemolymph data for phenoloxidase activity,
protein content, and glutathione concentrationPO, GSH, PQ data.xlsx