Quantification of Thermal Acclimation in Immune Functions in Ectothermic Animals

Area of Science:

• Ecoimmunology
• Animal Physiology
• Environmental Science

Background:

• Immune acclimation to temperature influences host-pathogen interactions and fitness.
• Ecoimmunology research has historically focused on vertebrates and insects, but thermal acclimation is relevant across diverse animal taxa.
• There's a recent surge in studies investigating thermal acclimation in animal immune function.

Purpose of the Study:

• To review and categorize current experimental designs for quantifying immune acclimation in animals.
• To evaluate the strengths and weaknesses of different approaches in assessing thermal acclimation mechanisms.
• To highlight the importance of combining various methodologies for a comprehensive understanding.

Main Methods:

• Categorization of studies into three main approaches: natural thermal variation, in vivo manipulation, and in vitro assays.
• Analysis of experimental designs focusing on organismal and cellular levels of immune acclimation.
• Emphasis on functional assays, such as phagocytosis, for assessing immune cell performance.

Main Results:

• Experimental designs vary, including studies on natural seasonal changes, captive animal manipulations, and laboratory-based assays.
• Both organismal and cellular mechanisms contribute to immune acclimation, and these are not mutually exclusive.
• Functional assays offer a versatile method to differentiate between changes in immune cell quantity and cellular function.

Conclusions:

• A combination of natural variation studies, in vivo, and in vitro methods is essential for advancing the understanding of animal immune acclimation.
• Functional immune cell assays provide an accessible, non-taxa-specific approach to dissecting acclimation mechanisms.
• Further research combining these approaches will illuminate the diversity of strategies animals employ to adapt their immune systems to changing thermal environments.