Related Experiment Videos
Fever and reduced iron: their interaction as a host defense response to bacterial infection
Abstract:
When rabbits are infected with Pasteurella multocida, the concentration of iron in their plasma decreases and their rectal temperature rises. To determine whether the rise in body temperature (fever) and the fall in plasma iron may be a coordinated host defense response, Pasteurella multocida were grown in vitro at various temperatures and iron concentrations. At afebrile temperatures the bacteria grew equally well at low or high concentrations of iron. However, when the temperature of the bath was raised to a febrile temperature the growth of the bacteria was inhibited by the low, but not the high, iron concentrations. These data support the hypothesis that one of the mechanisms behind the adaptive (or beneficial) role of fever is the reduced ability of pathogenic bacteria to grow well at elevated temperatures in an iron-poor medium.
Insights
Fever may help fight infection by making it harder for bacteria like Pasteurella multocida to grow. This study shows febrile temperatures combined with low iron inhibit bacterial growth, supporting fever as a host defense mechanism.
Area of Science:
- Microbiology
- Immunology
- Veterinary Medicine
Background:
- Infection with Pasteurella multocida in rabbits causes decreased plasma iron and elevated rectal temperature.
- Fever and hypoferremia are potential coordinated host defense responses.
Purpose of the Study:
- To investigate if fever and reduced plasma iron act together to inhibit bacterial growth.
- To determine the role of temperature and iron availability in the growth of Pasteurella multocida.
Main Methods:
- Pasteurella multocida were cultured in vitro under varying temperature and iron concentration conditions.
- Bacterial growth was assessed at both afebrile and febrile temperatures with differing iron levels.
Main Results:
- At afebrile temperatures, Pasteurella multocida growth was not affected by iron concentration.
- At febrile temperatures, bacterial growth was inhibited in low-iron conditions but not in high-iron conditions.
Conclusions:
- Elevated body temperature (fever) combined with low iron availability impairs Pasteurella multocida growth.
- This suggests that fever is an adaptive host defense mechanism that reduces the ability of pathogenic bacteria to thrive in an iron-poor environment.