An ecoimmunological approach to disease in tortoises reveals the importance of lymphocytes

Loading...
Thumbnail Image

Authors

Sandmeier, Franziska C.
Weitzman, Chava L.
Tracy C. Richard

Issue Date

2018

Type

Article

Language

Keywords

chronic disease , ectotherm , inflammation , phagocytosis , reptile , temperature

Research Projects

Organizational Units

Journal Issue

Alternative Title

Abstract

We quantified the severity of upper respiratory tract disease (URTD) and immunological metrics (differential white blood cell counts and bacteria-killing ability of blood plasma) in relation to climatic variables in 20 populations of Mojave desert tortoise (Gopherus agassizii). Prevalence and infection intensity of Mycoplasma agassizii, an etiological agent of URTD, have previously been quantified for these populations (Weitzman et al. 2017). Immunological variables were reduced by principal component analyses and separated into cells involved in inflammation (PC1) and cellular functions mediated by lymphocytes and basophils (PC2). In population-level models, the mean number of lymphocytes per individual was associated with mean annual number of days below freezing. Lymphocytes were also positively associated with mean infection intensity of M. agassizii. Additionally, prevalence of URTD was closely associated with PC1 (cells associated with inflammation). This suggests that at least two immunological strategies are involved in responding to M.agassizii, one that involves primarily lymphocytes and one that involves inflammatory mechanisms. Recent studies on immunology in Testudines suggest that a large proportion of lymphocytes in this taxon are similar to B-1 lymphocytes of mammals and have phagocytic properties. Controlled experiments are needed to understand the disease mitigation of these lymphocytes in desert tortoises.

Description

Citation

Sandmeier, F. C., Weitzman, C. L., & Tracy, C. R. (2018). An ecoimmunological approach to disease in tortoises reveals the importance of lymphocytes. Ecosphere, 9(9), e02427. doi:10.1002/ecs2.2427

Publisher

License

Creative Commons Attribution 3.0 Unported

Journal

Volume

Issue

PubMed ID

ISSN

2150-8925

EISSN

Collections