1
|
Siracusa ER, Pavez-Fox MA, Negron-Del Valle JE, Phillips D, Platt ML, Snyder-Mackler N, Higham JP, Brent LJN, Silk MJ. Social ageing can protect against infectious disease in a group-living primate. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.09.584237. [PMID: 38559098 PMCID: PMC10979879 DOI: 10.1101/2024.03.09.584237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The benefits of social living are well established, but sociality also comes with costs, including infectious disease risk. This cost-benefit ratio of sociality is expected to change across individuals' lifespans, which may drive changes in social behaviour with age. To explore this idea, we combine data from a group-living primate for which social ageing has been described with epidemiological models to show that having lower social connectedness when older can protect against the costs of a hypothetical, directly transmitted endemic pathogen. Assuming no age differences in epidemiological characteristics (susceptibility to, severity, and duration of infection), older individuals suffered lower infection costs, which was explained largely because they were less connected in their social networks than younger individuals. This benefit of 'social ageing' depended on epidemiological characteristics and was greatest when infection severity increased with age. When infection duration increased with age, social ageing was beneficial only when pathogen transmissibility was low. Older individuals benefited most from having a lower frequency of interactions (strength) and network embeddedness (closeness) and benefited less from having fewer social partners (degree). Our study provides a first examination of the epidemiology of social ageing, demonstrating the potential for pathogens to influence evolutionary dynamics of social ageing in natural populations.
Collapse
Affiliation(s)
- Erin R. Siracusa
- School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | | | | | - Daniel Phillips
- Center for Evolution and Medicine, Arizona State University, Arizona, USA
| | - Michael L. Platt
- Department of Neuroscience, University of Pennsylvania, PA, USA
- Department of Psychology, University of Pennsylvania, PA, USA
- Department of Marketing, University of Pennsylvania, PA, USA
| | - Noah Snyder-Mackler
- Center for Evolution and Medicine, Arizona State University, Arizona, USA
- School of Life Sciences, Arizona State University, Arizona, USA
- School for Human Evolution and Social Change, Arizona State University, Arizona, USA
| | - James P. Higham
- Department of Anthropology, New York University, New York, USA
| | - Lauren J. N. Brent
- School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | - Matthew J. Silk
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
2
|
Svobodová M, Čepička I, Zídková L, Kassahun A, Votýpka J, Peške L, Hrazdilová K, Brzoňová J, Voříšek P, Weidinger K. Blood parasites (Trypanosoma, Leucocytozoon, Haemoproteus) in the Eurasian sparrowhawk (Accipiter nisus): diversity, incidence and persistence of infection at the individual level. Parasit Vectors 2023; 16:15. [PMID: 36641440 PMCID: PMC9840293 DOI: 10.1186/s13071-022-05623-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 12/17/2022] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND A high prevalence of parasites may result from life-long persistence of infection or from high reinfection rates. We have studied blood parasites in a breeding population of the accipitrid raptor, Eurasian sparrowhawk (Accipiter nisus), to determine parasite diversity and turnover. METHODS During this 7-year study, 210 adult Eurasian sparrowhawks breeding in the city of Prague were checked for parasites using several diagnostic methods. RESULTS In both female and male raptors, parasites of the genus Leucocytozoon were the most prevalent (92% and 85%, respectively) followed in decreasing order of prevalence by those of genus Trypanosoma (74% and 68%, respectively) and genus Haemoproteus (46% and 16%, respectively). The prevalence of all parasites increased with age in both sexes, with the females at each respective age having the higher prevalence. There was a positive association between Haemoproteus and Leucocytozoon infections. Persistence at the individual level was higher than incidence for Trypanosoma and Haemoproteus. In the case of Leucocytozoon and Trypanosoma, most individuals probably become infected in their first year of life or even before dispersal from the nest. The detected parasites belonged to Trypanosoma avium sensu stricto, Leucocytozoon sp. (haplotypes ACNI1 and ACNI3) and Leucocytozoon mathisi (haplotype ACNI4) and two new lineages of the Haemoproteus elani complex (ACCNIS6 and ACCNIS7). Detailed analysis of parasite lineages in individuals that were repeatedly sampled revealed lineage turnover that would otherwise remain hidden. Phylogenetic analysis revealed that the detected Haemoproteus belongs to a phylogenetically distant group whose taxonomic position requires further analysis. CONCLUSIONS All three genera of blood parasites persist in infected individuals, thus enabling sustainability of vector transmission cycles. Prevalence increases with age; however, there is a high turnover of Leucocytozoon lineages. No clear evidence of parasite-induced mortality was found, and most of the individuals were infected early in life, particularly in the case of Leucocytozoon.
Collapse
Affiliation(s)
- Milena Svobodová
- grid.4491.80000 0004 1937 116XDepartment of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Ivan Čepička
- grid.4491.80000 0004 1937 116XDepartment of Zoology, Faculty of Science, Charles University, Prague, Czechia
| | - Lenka Zídková
- grid.4491.80000 0004 1937 116XDepartment of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Aysheshm Kassahun
- grid.4491.80000 0004 1937 116XDepartment of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Jan Votýpka
- grid.4491.80000 0004 1937 116XDepartment of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | | | - Kristýna Hrazdilová
- grid.7112.50000000122191520Department of Chemistry and Biochemistry, Mendel University, Brno, Czechia ,grid.4491.80000 0004 1937 116XBiomedical Center, Faculty of Medicine in Pilsen, Charles University, Plzeň, Czechia
| | - Jana Brzoňová
- grid.4491.80000 0004 1937 116XDepartment of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Petr Voříšek
- grid.475834.9Czech Society for Ornithology, Prague, Czechia
| | - Karel Weidinger
- grid.10979.360000 0001 1245 3953Department of Zoology, Faculty of Science, Palacký University, Olomouc, Olomouc, Czechia
| |
Collapse
|
3
|
Wolf SE, Sanders TL, Beltran SE, Rosvall KA. The telomere regulatory gene POT1 responds to stress and predicts performance in nature: Implications for telomeres and life history evolution. Mol Ecol 2022; 31:6155-6171. [PMID: 34674335 DOI: 10.1111/mec.16237] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 09/25/2021] [Accepted: 10/12/2021] [Indexed: 02/02/2023]
Abstract
Telomeres are emerging as correlates of fitness-related traits and may be important mediators of ecologically relevant variation in life history strategies. Growing evidence suggests that telomere dynamics can be more predictive of performance than length itself, but very little work considers how telomere regulatory mechanisms respond to environmental challenges or influence performance in nature. Here, we combine observational and experimental data sets from free-living tree swallows (Tachycineta bicolor) to assess how performance is predicted by the telomere regulatory gene POT1, which encodes a shelterin protein that sterically blocks telomerase from repairing the telomere. First, we show that lower POT1 gene expression in the blood was associated with higher female quality, that is, earlier breeding and heavier body mass. We next challenged mothers with an immune stressor (lipopolysaccharide injection) that led to "sickness" in mothers and 24 h of food restriction in their offspring. While POT1 did not respond to maternal injection, females with lower constitutive POT1 gene expression were better able to maintain feeding rates following treatment. Maternal injection also generated a 1-day stressor for chicks, which responded with lower POT1 gene expression and elongated telomeres. Other putatively stress-responsive mechanisms (i.e., glucocorticoids, antioxidants) showed marginal responses in stress-exposed chicks. Model comparisons indicated that POT1 mRNA abundance was a largely better predictor of performance than telomere dynamics, indicating that telomere regulators may be powerful modulators of variation in life history strategies.
Collapse
Affiliation(s)
- Sarah E Wolf
- Department of Biology, Indiana University, Bloomington, Indiana, USA.,Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana, USA
| | - Tiana L Sanders
- Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana, USA
| | - Sol E Beltran
- Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana, USA
| | - Kimberly A Rosvall
- Department of Biology, Indiana University, Bloomington, Indiana, USA.,Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana, USA
| |
Collapse
|
4
|
Wolf SE, Rosvall KA. A multi-tissue view on telomere dynamics and postnatal growth. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:346-355. [PMID: 34964306 PMCID: PMC8989676 DOI: 10.1002/jez.2571] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 11/11/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
Trade-offs between growth and self-maintenance are common in nature, such that early-life effects on growth can generate lasting consequences on survival and longevity. Telomeres-putative biomarkers of self-maintenance-may link early growth with these later phenotypic effects, but evidence for growth-telomere trade-offs is mixed. Null or even positive relationships between growth and telomeres may be driven by heterogeneity in resource availability or invariable allocation towards telomere maintenance within a population. We used nestling tree swallows (Tachycineta bicolor) to assess the directionality and timing of relationships between growth and telomere length in several tissues. We focused on two important phases of growth: first, the peak of postnatal growth occurring around 6 days old when nestlings grow by ~33% in a single day, and subsequently, the later phase of growth occurring as body mass plateaus near adult size at 12 days old. We quantified telomere attrition in blood during postnatal growth, as well as telomere length in the blood, brain, adrenals, and liver at 12 days old. Growth was unrelated to telomere length in the liver and telomere dynamics in blood. However, brain telomere length was positively correlated with peak growth, and adrenal telomere length was positively related to later growth, particularly for chicks that had experienced a temporary stressor. These observations suggest that variation in resource availability may mask trade-offs, generating positive correlations between growth and telomere length at the population level. They also provide insights into complex relationships between growth and self-maintenance that can be revealed by looking in multiple tissues.
Collapse
Affiliation(s)
- Sarah E Wolf
- Department of Biology, Indiana University, Bloomington, Indiana, USA
- Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana, USA
| | - Kimberly A Rosvall
- Department of Biology, Indiana University, Bloomington, Indiana, USA
- Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana, USA
| |
Collapse
|
5
|
Butler MW, Stierhoff EN, Carpenetti JM, Bertone MA, Addesso AM, Knutie SA. Oxidative damage increases with degree of simulated bacterial infection, but not ectoparasitism, in tree swallow nestlings. J Exp Biol 2021; 224:272162. [PMID: 34427672 DOI: 10.1242/jeb.243116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/18/2021] [Indexed: 11/20/2022]
Abstract
The purpose of mounting an immune response is to destroy pathogens, but this response comes at a physiological cost, including the generation of oxidative damage. However, many studies on the effects of immune challenges employ a single high dose of a simulated infection, meaning that the consequences of more mild immune challenges are poorly understood. We tested whether the degree of immunological challenge in tree swallows (Tachycineta bicolor) affects oxidative physiology and body mass, and whether these metrics correlate with parasitic nest mite load. We injected 14 day old nestlings with 0, 0.01, 0.1 or 1 mg lipopolysaccharide (LPS) per kg body mass, then collected a blood sample 24 h later to quantify multiple physiological metrics, including oxidative damage (i.e. d-ROMs), circulating amounts of triglyceride and glycerol, and levels of the acute phase protein haptoglobin. After birds had fledged, we identified and counted parasitic nest mites (Dermanyssus spp. and Ornithonyssus spp.). We found that only nestlings injected with 1 mg LPS kg-1 body mass, which is a common dosage in ecoimmunological studies, lost more body mass than individuals from other treatment groups. However, every dose of LPS resulted in a commensurate increase in oxidative damage. Parasitic mite abundance had no effect on oxidative damage across treatments. The amount of oxidative damage correlated with haptoglobin levels, suggesting compensatory mechanisms to limit self-damage during an immune response. We conclude that while only the highest-intensity immune challenges resulted in costs related to body mass, even low-intensity immune challenges result in detectable increases in oxidative damage.
Collapse
Affiliation(s)
| | | | | | - Matthew A Bertone
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA
| | - Alyssa M Addesso
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Sarah A Knutie
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA.,Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA
| |
Collapse
|
6
|
Seppälä O, Çetin C, Cereghetti T, Feulner PGD, Adema CM. Examining adaptive evolution of immune activity: opportunities provided by gastropods in the age of 'omics'. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200158. [PMID: 33813886 DOI: 10.1098/rstb.2020.0158] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Parasites threaten all free-living organisms, including molluscs. Understanding the evolution of immune defence traits in natural host populations is crucial for predicting their long-term performance under continuous infection risk. Adaptive trait evolution requires that traits are subject to selection (i.e. contribute to organismal fitness) and that they are heritable. Despite broad interest in the evolutionary ecology of immune activity in animals, the understanding of selection on and evolutionary potential of immune defence traits is far from comprehensive. For instance, empirical observations are only rarely in line with theoretical predictions of immune activity being subject to stabilizing selection. This discrepancy may be because ecoimmunological studies can typically cover only a fraction of the complexity of an animal immune system. Similarly, molecular immunology/immunogenetics studies provide a mechanistic understanding of immunity, but neglect variation that arises from natural genetic differences among individuals and from environmental conditions. Here, we review the current literature on natural selection on and evolutionary potential of immune traits in animals, signal how merging ecological immunology and genomics will strengthen evolutionary ecological research on immunity, and indicate research opportunities for molluscan gastropods for which well-established ecological understanding and/or 'immune-omics' resources are already available. This article is part of the Theo Murphy meeting issue 'Molluscan genomics: broad insights and future directions for a neglected phylum'.
Collapse
Affiliation(s)
- Otto Seppälä
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
| | - Cansu Çetin
- Department of Aquatic Ecology, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.,Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
| | - Teo Cereghetti
- Department of Aquatic Ecology, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.,Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
| | - Philine G D Feulner
- Department of Fish Ecology and Evolution, Centre of Ecology, Evolution and Biogeochemistry, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum, Switzerland.,Division of Aquatic Ecology and Evolution, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Coen M Adema
- Department of Biology, Center for Evolutionary and Theoretical Immunology, University of New Mexico, Albuquerque, NM, USA
| |
Collapse
|
7
|
Muriel J, Vida C, Gil D, Pérez-Rodríguez L. Ontogeny of leukocyte profiles in a wild altricial passerine. J Comp Physiol B 2020; 191:195-206. [PMID: 33196859 DOI: 10.1007/s00360-020-01323-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/08/2020] [Accepted: 10/28/2020] [Indexed: 11/30/2022]
Abstract
Ecophysiological studies have highlighted the relevance of the avian immune system in individual fitness prospects in the wild. However, studies on the ontogeny of avian immunity are scarce. We analyse age-related changes in the cellular constitutive immunity throughout nestling development, as well as its relationship with sex and brood size. We found that cellular constitutive immunity could be affected by age, sex, brood size, or daily rhythm. Early-stage nestlings relied more on cells of the innate immunity rather than on cells linked to the adaptive immune system. Cellular immunity may not be fully mature in fledglings, as reflected by differences in phagocytic cell counts with regard to adults. Beyond the age-dependent effects, agranulocyte cell counts were affected by sibling competition while granulocyte cell counts showed a daily rhythm. We also show that the heterophil to lymphocyte ratio was negatively related to body weight when nestlings become more independent. Our study contributes knowledge to the fields of developmental immunology and ecological immunology based on essential components of the cellular immune system.
Collapse
Affiliation(s)
- Jaime Muriel
- Instituto Pirenaico de Ecología, IPE (CSIC), Avda. Nuestra Señora de la Victoria 16, 22700, Jaca, Spain.
| | - Carmen Vida
- Department of Biology Systems, Faculty of Medicine, University of Alcalá, C/19, Av. de Madrid, Km 33,600, 28871, Alcalá de Henares,, Madrid, Spain
| | - Diego Gil
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal 2, 28006, Madrid, Spain
| | - Lorenzo Pérez-Rodríguez
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC, UCLM, JCCM), Ronda de Toledo 12, 13005, Ciudad Real, Spain
| |
Collapse
|
8
|
van Lieshout SHJ, Badás EP, Mason MWT, Newman C, Buesching CD, Macdonald DW, Dugdale HL. Social effects on age-related and sex-specific immune cell profiles in a wild mammal. Biol Lett 2020; 16:20200234. [PMID: 32673548 PMCID: PMC7423055 DOI: 10.1098/rsbl.2020.0234] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Evidence for age-related changes in innate and adaptive immune responses is increasing in wild populations. Such changes have been linked to fitness, and knowledge of the factors driving immune response variation is important for understanding the evolution of immunity. Age-related changes in immune profiles may be owing to factors such as immune system development, sex-specific behaviour and responses to environmental conditions. Social environments may also contribute to variation in immunological responses, for example, through transmission of pathogens and stress arising from resource and mate competition. Yet, the impact of the social environment on age-related changes in immune cell profiles is currently understudied in the wild. Here, we tested the relationship between leukocyte cell composition (proportion of neutrophils and lymphocytes [innate and adaptive immunity, respectively] that were lymphocytes) and age, sex and group size in a wild population of European badgers (Meles meles). We found that the proportion of lymphocytes in early life was greater in males in smaller groups compared to larger groups, but with a faster age-related decline in smaller groups. By contrast, the proportion of lymphocytes in females was not significantly related to age or group size. Our results provide evidence of sex-specific age-related changes in immune cell profiles in a wild mammal, which are influenced by the social environment.
Collapse
Affiliation(s)
- Sil H J van Lieshout
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Elisa P Badás
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.,Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Michael W T Mason
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Chris Newman
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Abingdon, Oxfordshire OX13 5QL, UK
| | - Christina D Buesching
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Abingdon, Oxfordshire OX13 5QL, UK
| | - David W Macdonald
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Abingdon, Oxfordshire OX13 5QL, UK
| | - Hannah L Dugdale
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.,Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
| |
Collapse
|
9
|
Judson JM, Reding DM, Bronikowski AM. Immunosenescence and its influence on reproduction in a long-lived vertebrate. J Exp Biol 2020; 223:jeb223057. [PMID: 32376708 PMCID: PMC7328165 DOI: 10.1242/jeb.223057] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 05/01/2020] [Indexed: 12/20/2022]
Abstract
Immunosenescence is a well-known phenomenon in mammal systems, but its relevance in other long-lived vertebrates is less understood. Further, the influence of age and reproductive effort on immune function in long-lived species can be challenging to assess, as long-term data are scarce and it is often difficult to sample the oldest age classes. We used the painted turtle (Chrysemys picta) to test hypotheses of immunosenescence and a trade-off between reproductive output and immune function in a population of a long-lived vertebrate that has been monitored for over 30 years. These long-term data were utilized to employ a unique approach of aging turtles with mark-recapture data and population-specific growth modeling to obtain more accurate estimates of age. We analyzed natural antibodies, lysis ability and bactericidal competence in 126 individuals from 1 to 33 years of age captured during May and June 2011. Older turtles exhibited greater natural antibody levels than young individuals. Young females with large clutches exhibited greater lysis ability, while older females with large clutches had decreased lysis ability, suggesting a trade-off between reproductive output and immune function conditional upon age. However, bactericidal competence increased later in the nesting season for older females. Our study rejects the hypothesis of immunosenescence in a long-lived turtle, despite evidence of actuarial and reproductive senescence in this population. Additionally, we detected mixed evidence for a trade-off between reproduction and immune health.
Collapse
Affiliation(s)
- Jessica M Judson
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011, USA
| | - Dawn M Reding
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011, USA
| | - Anne M Bronikowski
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, 251 Bessey Hall, Ames, IA 50011, USA
| |
Collapse
|
10
|
Armour EM, Bruner TL, Hines JK, Butler MW. Low-dose immune challenges result in detectable levels of oxidative damage. J Exp Biol 2020; 223:jeb220095. [PMID: 32054680 DOI: 10.1242/jeb.220095] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 02/10/2020] [Indexed: 08/26/2023]
Abstract
Infection can result in substantial costs to animals, so they frequently respond by removing infectious agents with an immune response. However, immune responses entail their own costs, including upregulation of processes that destroy pathogens (e.g. the production of reactive oxygen species) and processes that limit the extent of self-damage during the immune response (e.g. production of anti-inflammatory proteins such as haptoglobin). Here, we simulated bacterial infection across a 1000-fold range using lipopolysaccharide (LPS) administered to northern bobwhite quail (Colinus virginianus), and quantified metrics related to pro-inflammatory conditions [i.e. generation of oxidative damage (d-ROMs), depletion of antioxidant capacity], anti-inflammatory mechanisms (i.e. production of haptoglobin, expression of the enzyme heme oxygenase, production of the organic molecule biliverdin) and nutritional physiology (e.g. circulating triglyceride levels, maintenance of body mass). We detected increases in levels of haptoglobin and d-ROMs even at LPS doses that are 1/1000th the concentration of doses frequently used in ecoimmunological studies, while loss of body mass and decreases in circulating triglycerides manifested only in individuals receiving the highest dose of LPS (1 mg LPS kg-1 body mass), highlighting variation among dose-dependent responses. Additionally, individuals that lost body mass during the course of the experiment had lower levels of circulating triglycerides, and those with more oxidative damage had greater levels of heme oxygenase expression, which highlights the complex interplay between pro- and anti-inflammatory processes. Because low doses of LPS may simulate natural infection levels, variation in dose-dependent physiological responses may be particularly important in modeling how free-living animals navigate immune challenges.
Collapse
Affiliation(s)
- Ellen M Armour
- Department of Biology, Lafayette College, Easton, PA 18042, USA
| | - Taylor L Bruner
- Department of Chemistry, Lafayette College, Easton, PA 18042, USA
| | - Justin K Hines
- Department of Chemistry, Lafayette College, Easton, PA 18042, USA
| | | |
Collapse
|
11
|
Merrill L, Ospina EA, Santymire RM, Benson TJ. Egg Incubation Temperature Affects Development of Innate Immune Function in Nestling American Robins (Turdus migratorius). Physiol Biochem Zool 2020; 93:1-12. [DOI: 10.1086/705361] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
12
|
Sparks AM, Watt K, Sinclair R, Pilkington JG, Pemberton JM, McNeilly TN, Nussey DH, Johnston SE. The genetic architecture of helminth-specific immune responses in a wild population of Soay sheep (Ovis aries). PLoS Genet 2019; 15:e1008461. [PMID: 31697674 PMCID: PMC6863570 DOI: 10.1371/journal.pgen.1008461] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 11/19/2019] [Accepted: 10/04/2019] [Indexed: 12/22/2022] Open
Abstract
Much of our knowledge of the drivers of immune variation, and how these responses vary over time, comes from humans, domesticated livestock or laboratory organisms. While the genetic basis of variation in immune responses have been investigated in these systems, there is a poor understanding of how genetic variation influences immunity in natural, untreated populations living in complex environments. Here, we examine the genetic architecture of variation in immune traits in the Soay sheep of St Kilda, an unmanaged population of sheep infected with strongyle gastrointestinal nematodes. We assayed IgA, IgE and IgG antibodies against the prevalent nematode Teladorsagia circumcincta in the blood plasma of > 3,000 sheep collected over 26 years. Antibody levels were significantly heritable (h2 = 0.21 to 0.57) and highly stable over an individual’s lifespan. IgA levels were strongly associated with a region on chromosome 24 explaining 21.1% and 24.5% of heritable variation in lambs and adults, respectively. This region was adjacent to two candidate loci, Class II Major Histocompatibility Complex Transactivator (CIITA) and C-Type Lectin Domain Containing 16A (CLEC16A). Lamb IgA levels were also associated with the immunoglobulin heavy constant loci (IGH) complex, and adult IgE levels and lamb IgA and IgG levels were associated with the major histocompatibility complex (MHC). This study provides evidence of high heritability of a complex immunological trait under natural conditions and provides the first evidence from a genome-wide study that large effect genes located outside the MHC region exist for immune traits in the wild. Understanding how immune responses vary in natural populations can give an insight into how infection affects the ability of hosts and parasites to survive and reproduce, and how this drives evolutionary and ecological dynamics. Yet, very little is known about how immune responses vary over an individual’s lifetime and how genes contribute to this variation under natural conditions. Our study investigates the genetic architecture of variation in three antibody types, IgA, IgE and IgG in a wild population of Soay sheep on the St Kilda archipelago in North-West Scotland. Using data collected over 26 years, we show that antibody levels have a heritable basis in lambs and adults and are stable over an individual’s lifetime. We also identify several genomic regions with large effects on immune responses. Our study offers the first insights into the genetic control of immunity in a wild population, which is essential to understand how immune profiles vary in challenging natural conditions and how natural selection maintains genetic variation in complex immune traits.
Collapse
Affiliation(s)
- Alexandra M. Sparks
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Faculty of Biological Sciences, School of Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
| | - Kathryn Watt
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Rona Sinclair
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Jill G. Pilkington
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Josephine M. Pemberton
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Tom N. McNeilly
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian, United Kingdom
| | - Daniel H. Nussey
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Susan E. Johnston
- Institutes of Evolutionary Biology and Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
13
|
Peters A, Delhey K, Nakagawa S, Aulsebrook A, Verhulst S. Immunosenescence in wild animals: meta‐analysis and outlook. Ecol Lett 2019; 22:1709-1722. [DOI: 10.1111/ele.13343] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 05/30/2019] [Accepted: 06/18/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Anne Peters
- School of Biological Sciences Monash University Clayton Vic. 3800 Australia
| | - Kaspar Delhey
- School of Biological Sciences Monash University Clayton Vic. 3800 Australia
| | - Shinichi Nakagawa
- School of Biological, Earth and Environmental Sciences University of New South Wales Sydney NSW 2052 Australia
| | - Anne Aulsebrook
- School of Biological Sciences Monash University Clayton Vic. 3800 Australia
- School of BioSciences University of Melbourne Parkville Vic. 3010 Australia
| | - Simon Verhulst
- Groningen Institute for Evolutionary Life Sciences University of Groningen 9747 AGGroningen The Netherlands
| |
Collapse
|
14
|
Giraudeau M, Angelier F, Sepp T. Do Telomeres Influence Pace-of-Life-Strategies in Response to Environmental Conditions Over a Lifetime and Between Generations? Bioessays 2019; 41:e1800162. [DOI: 10.1002/bies.201800162] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/06/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Mathieu Giraudeau
- CREEC; 911 Avenue Agropolis; BP 6450134394 Montpellier Cedex 5 France
- MIVEGEC; UMR IRD/CNRS/UM 5290; 911 Avenue Agropolis, BP 6450134394 Montpellier Cedex 5 France
| | - Frederic Angelier
- CNRS CEBC-ULR; UMR 7372; Villiers en Bois 79360 Beauvoir sur Niort France
| | - Tuul Sepp
- Institute of Ecology and Earth Sciences; University of Tartu; Vanemuise 46 51014 Tartu Estonia
| |
Collapse
|
15
|
Zamora-Camacho FJ, Comas M. Early swelling response to phytohemagglutinin is lower in older toads. PeerJ 2018; 6:e6104. [PMID: 30595980 PMCID: PMC6304268 DOI: 10.7717/peerj.6104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 11/13/2018] [Indexed: 01/29/2023] Open
Abstract
The effects of age on performance of life-history traits are diverse, but a common outcome is senescence, an irreversible deterioration of physical and physiological capabilities of older individuals. Immune response is potentially bound to senescence. However, little is known about immune response ageing in amphibians. In this work, we test the hypothesis that amphibian early immune response is reduced in older individuals. To this end, we captured adult natterjack toads (Epidalea calamita) and inoculated them with phytohemagglutinin, an innocuous protein that triggers a skin-swelling immune response whose magnitude is directly proportional to the ability of the individual to mount an immune response. We measured early swelling immune response (corresponding to an innate-response stage) hourly, for six hours, and we calculated the area under the curve (AUC) for each individual's time series, as a measure of immune response magnitude incorporating time. We estimated toad age by means of phalanx skeletochronology. Swelling and AUC decreased with age. Therefore, in accordance with our predictions, early immune response seems subject to senescence in these toads. Reduced ability to get over infections due to senescence of immune respose might be-together with a worse functioning of other organs and systems-among the causes of lower survival of older specimens.
Collapse
Affiliation(s)
- Francisco Javier Zamora-Camacho
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States of America
- Department of Biogeography and Global Change, Museo Nacional de Ciencias Naturales (MNCN), Spanish National Research Council (CSIC), Madrid, Spain
| | - Mar Comas
- Department of Integrative Ecology, Estación Biológica de Doñana (EBD), Spanish National Research Council (CSIC), Sevilla, Spain
| |
Collapse
|
16
|
Palacios MG, D'Amico VL, Bertellotti M. Ecotourism effects on health and immunity of Magellanic penguins at two reproductive colonies with disparate touristic regimes and population trends. CONSERVATION PHYSIOLOGY 2018; 6:coy060. [PMID: 30464841 PMCID: PMC6233856 DOI: 10.1093/conphys/coy060] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 09/26/2018] [Accepted: 10/16/2018] [Indexed: 06/09/2023]
Abstract
Negative effects of ecotourism on wildlife are rising worldwide. Conservation physiology can play a major role in protecting wildlife by providing early alerts on changes in the status of individuals exposed to tourist activities. We measured an integrated set of immune and health-state indices to evaluate the effects of ecotourism on Magellanic penguins (Spheniscus magellanicus). We studied two reproductive colonies that differed in the intensity of tourism and population trends: Punta Tombo (higher tourism intensity, declining population) and San Lorenzo (lower tourism intensity, growing population). Within each colony, we compared individuals from an area that was exposed to tourists and a control area where tourism was excluded. Adult penguins exposed to tourism at Punta Tombo, but not at San Lorenzo, showed physiological alterations indicative of chronic stress (higher heterophil to lymphocyte ratios) and parasitic infection (elevated heterophil and eosinophil counts). Penguin chicks exposed to tourism at Punta Tombo, but not at San Lorenzo, also showed physiological alterations indicative of poor immune and general-health condition: lower humoral innate immunity, haematocrit, and glucose levels and higher inflammatory responses likely due to increased prevalence of fleas. Our results indicate that individuals of a declining population exposed to high levels of tourism express physiological indicators of chronic stress and poor health that could make adults and juveniles vulnerable to disease. These effects are expressed despite a long history of exposure and behavioural habituation to human visitation. In contrast, individuals of a growing population exposed to more recent and lower levels of tourism showed no effect. Our study demonstrates how a diverse physiological toolkit within a conservation physiology approach can provide important information for a better comprehension of anthropogenic effects on wild animals in our changing world.
Collapse
Affiliation(s)
- Maria G Palacios
- Applied Ecophysiology Group, Centro para el Estudio de Sistemas Marinos, Consejo Nacional de Investigaciones Científicas y Técnicas (CESIMAR-CONICET), Boulevard 2915 (9120) Puerto Madryn, Chubut, Argentina
| | - Verónica L D'Amico
- Applied Ecophysiology Group, Centro para el Estudio de Sistemas Marinos, Consejo Nacional de Investigaciones Científicas y Técnicas (CESIMAR-CONICET), Boulevard 2915 (9120) Puerto Madryn, Chubut, Argentina
| | - Marcelo Bertellotti
- Applied Ecophysiology Group, Centro para el Estudio de Sistemas Marinos, Consejo Nacional de Investigaciones Científicas y Técnicas (CESIMAR-CONICET), Boulevard 2915 (9120) Puerto Madryn, Chubut, Argentina
- Department of Production, Environment and Sustainable Development, University of Chubut, Alem 1573 (9120) Puerto Madryn, Chubut, Argentina
| |
Collapse
|
17
|
Sparks AM, Watt K, Sinclair R, Pilkington JG, Pemberton JM, Johnston SE, McNeilly TN, Nussey DH. Natural Selection on Antihelminth Antibodies in a Wild Mammal Population. Am Nat 2018; 192:745-760. [PMID: 30444657 DOI: 10.1086/700115] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
An effective immune response is expected to confer fitness benefits through improved resistance to parasites but also incur energetic costs that negatively impact fitness-related traits, such as reproduction. The fitness costs and benefits of an immune response are likely to depend on host age, sex, and levels of parasite exposure. Few studies have examined the full extent to which patterns of natural selection on immune phenotypes vary across demographic groups and environments in the wild. Here, we assessed natural selection on plasma levels of three functionally distinct isotypes (IgA, IgE, and IgG) of antibodies against a prevalent nematode parasite measured in a wild Soay sheep population over 26 years. We found little support for environment-dependent selection or reproductive costs. However, antibody levels were negatively associated with parasite egg counts and positively associated with subsequent survival, albeit in a highly age- and isotype-dependent manner. Raised levels of antiparasite IgA best predicted reduced egg counts, but this did not predict survival in lambs. In adults increased antiparasite IgG predicted reduced egg counts, and in adult females IgG levels also positively predicted overwinter survival. Our results highlight the potential importance of age- and sex-dependent selection on immune phenotypes in nature and show that patterns of selection can vary even among functionally related immune markers.
Collapse
|
18
|
Virgin EE, Rosvall KA. Endocrine-immune signaling as a predictor of survival: A prospective study in developing songbird chicks. Gen Comp Endocrinol 2018; 267:193-201. [PMID: 30099034 DOI: 10.1016/j.ygcen.2018.08.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/18/2018] [Accepted: 08/04/2018] [Indexed: 12/18/2022]
Abstract
Immune function varies with an animal's endocrine physiology and energy reserves, as well as its abiotic and biotic environment. This context-dependency is thought to relate to adaptive trade-off resolution that varies from one context to the next; however, it is less clear how state- and environmentally-dependent differences in endocrine-immune signaling relate to survival in natural populations. We begin to address this question in a prospective study on a free-living passerine bird, the tree swallow (Tachycineta bicolor), by capitalizing upon naturally-occurring variation in ectoparasitism in 12-day old chicks. We measured body mass, hematological gene expression of the pro-inflammatory cytokine interleukin-6 (IL-6) as well as corticosterone (CORT) secretion at baseline and in response to 30 min of handling. We found that chicks with ectoparasites had smaller body mass and higher levels of IL-6 gene expression at this critical stage of post-natal growth and development. Mass and IL-6 were positively correlated, but only among parasitized chicks, suggesting that larger chicks mount stronger immune responses when necessary, i.e. in the presence of ectoparasites that are known to induce inflammation. IL-6 mRNA expression was negatively correlated with stress-induced CORT levels, suggesting that this proxy of inflammation may be co-regulated with or coordinated by glucocorticoids. More importantly, these endocrine-immune parameters predicted survival to fledging, which was positively associated with IL-6 mRNA abundance and, to a lesser degree, CORT reactivity. These results suggest a link between endocrine-immune interactions and performance in nature, and as a consequence, they shed light on the potentially adaptive, context-dependent interplay between body mass, immunity, and endocrine physiology during development.
Collapse
Affiliation(s)
- Emily E Virgin
- Department of Biology, Indiana University, Bloomington, IN 47405, USA; Center for the Integrative Study of Animal Behavior (CISAB), Indiana University, Bloomington, IN 47405, USA
| | - Kimberly A Rosvall
- Department of Biology, Indiana University, Bloomington, IN 47405, USA; Center for the Integrative Study of Animal Behavior (CISAB), Indiana University, Bloomington, IN 47405, USA.
| |
Collapse
|
19
|
Patra G, Behera P, Kumar Borthakur S, Ghosh S, Biswas P, Kumar A, Debbarma A, Sahanawaz Alam S. Prevalence of Plasmodium relictum in four common bird species in India. BIOL RHYTHM RES 2018. [DOI: 10.1080/09291016.2018.1518211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Gautam Patra
- Department of Veterinary Parasitology, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Parthasarathi Behera
- Department of Veterinary Physiology and Biochemistry, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Sonjoy Kumar Borthakur
- Department of Veterinary Parasitology, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Subhamoy Ghosh
- Department of Veterinary Parasitology, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Papia Biswas
- Department of Veterinary Public Health and Epidemiology, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Ajit Kumar
- Department of Veterinary Parasitology, F/O – VAS, WBUAFS, Kolkata, West Bengal, India
| | - Apurba Debbarma
- Department of Veterinary Parasitology, College of Veterinary Sciences and Animal Husbandry, Agartala, West Tripura, India
| | | |
Collapse
|
20
|
Hegemann A, Pardal S, Matson KD. Indices of immune function used by ecologists are mostly unaffected by repeated freeze-thaw cycles and methodological deviations. Front Zool 2017; 14:43. [PMID: 28883887 PMCID: PMC5580329 DOI: 10.1186/s12983-017-0226-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 08/15/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Over the past couple of decades, measuring immunological parameters has become widespread in studies of ecology and evolution. A combination of different immunological indices is useful for quantifying different parts of the immune system and comprehensively assessing immune function. Running multiple immune assays usually requires samples to be repeatedly thawed and re-frozen. There is some evidence that repeated freezing and thawing can affect assay results, but this has never been comprehensively studied in some common ecological immunology assays. We tested the effect of multiple (1, 2, 3, 4, 5, 10) freeze-thaw cycles on the results of four commonly used immunological assays: haemolysis-haemagglutination titres, haptoglobin concentration, bacterial killing capacity and total immunoglobulins (IgY). We tested five different bird species from four different bird orders (Passeriformes, Columbiformes, Charadriiformes and Galliformes), and we included both captive and free-living individuals. In addition, we tested for haptoglobin concentrations and the haemolysis-haemagglutination assay if re-analysing samples 1 year apart led to different results. For the haemolysis-haemagglutination assay we also tested two different sources of rabbit blood, and we compared untreated microtitre plates with plates that were "blocked" to prevent nonspecific interactions between the plate and assay reagents. RESULTS Repeated freezing and thawing of plasma had no effect on lysis titres, haptoglobin concentrations, bacterial killing capacity, or total immunoglobulin levels. Agglutination titres were unaffected by up to five cycles but were lower after ten freeze-thaw cycles. For the haemolysis-haemagglutination assay and haptoglobin concentrations, re-analysing samples 1 year apart yielded highly correlated data. For the haemolysis-haemagglutination assay, the source of rabbit blood did not influence the results, and the untreated vs. blocked plates differed slightly overall, but at the individual level assay results were highly correlated. Using different rabbit blood sources or different types of microtitre plates yielded highly correlated data. CONCLUSIONS Our data suggest that repeated freeze-thaw cycles do not impair assay results to the point of influencing ecological or evolutionary conclusions. Plasma samples can be safely stored in one tube and thawed repeatedly for different assays. Nevertheless, we recommend consistent treatment of samples in terms of freeze-thaw cycles or other laboratory treatments to minimize the potential for introducing a systematic bias.
Collapse
Affiliation(s)
- Arne Hegemann
- Department of Biology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
| | - Sara Pardal
- MARE - Marine and Environmental Sciences Centre, Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal
| | - Kevin D Matson
- Resource Ecology Group, Environmental Sciences Department, Wageningen University, 6700 AA Wageningen, The Netherlands
| |
Collapse
|
21
|
Zimmerman LM, Carter AW, Bowden RM, Vogel LA. Immunocompetence in a long‐lived ectothermic vertebrate is temperature dependent but shows no decline in older adults. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12867] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Laura M. Zimmerman
- School of Biological Sciences Illinois State University Campus Box 4120, Normal IL 61790‐4120 USA
- Department of Biology Millikin University 1184 W. Main St., Decatur IL 62522 USA
| | - Amanda Wilson Carter
- School of Biological Sciences Illinois State University Campus Box 4120, Normal IL 61790‐4120 USA
| | - Rachel M. Bowden
- School of Biological Sciences Illinois State University Campus Box 4120, Normal IL 61790‐4120 USA
| | - Laura A. Vogel
- School of Biological Sciences Illinois State University Campus Box 4120, Normal IL 61790‐4120 USA
| |
Collapse
|
22
|
Watson RL, McNeilly TN, Watt KA, Pemberton JM, Pilkington JG, Waterfall M, Hopper PRT, Cooney D, Zamoyska R, Nussey DH. Cellular and humoral immunity in a wild mammal: Variation with age & sex and association with overwinter survival. Ecol Evol 2016; 6:8695-8705. [PMID: 28035261 PMCID: PMC5192870 DOI: 10.1002/ece3.2584] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/07/2016] [Accepted: 10/10/2016] [Indexed: 12/31/2022] Open
Abstract
Immune defenses are expected to be crucial for survival under the considerable parasite pressures experienced by wild animals. However, our understanding of the association between immunity and fitness in nature remains limited due to both the complexity of the vertebrate immune system and the often‐limited availability of immune reagents in nonmodel organisms. Here, we use methods and reagents developed by veterinary researchers for domestic ungulates on blood samples collected from a wild Soay sheep population, to evaluate an unusually broad panel of immune parameters. Our evaluation included different innate and acquired immune cell types as well as nematode parasite‐specific antibodies of different isotypes. We test how these markers correlate with one another, how they vary with age‐group and sex, and, crucially, whether they predict overwinter survival either within or among demographic groups. We found anticipated patterns of variation in markers with age, associated with immune development, and once these age trends were accounted for, correlations among our 11 immune markers were generally weak. We found that females had higher proportions of naïve T cells and gamma–delta T cells than males, independent of age, while our other markers did not differ between sexes. Only one of our 11 markers predicted overwinter survival: sheep with higher plasma levels of anti‐nematode IgG antibodies were significantly more likely to survive the subsequent high mortality winter, independent of age, sex, or weight. This supports a previous finding from this study system using a different set of samples and shows that circulating antibody levels against ecologically relevant parasites in natural systems represent an important parameter of immune function and may be under strong natural selection. Our data provide rare insights into patterns of variation among age‐ and sex groups in different T‐cell subsets and antibody levels in the wild, and suggest that certain types of immune response—notably those likely to be repeatable within individuals and linked to resistance to ecologically relevant parasites—may be most informative for research into the links between immunity and fitness under natural conditions.
Collapse
Affiliation(s)
- Rebecca L Watson
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | | | - Kathryn A Watt
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Josephine M Pemberton
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Jill G Pilkington
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Martin Waterfall
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Phoebe R T Hopper
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Daniel Cooney
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Rose Zamoyska
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| | - Daniel H Nussey
- School of Biological Sciences Institutes of Evolutionary Biology & Immunology and Infection Research University of Edinburgh Edinburgh UK
| |
Collapse
|
23
|
Beirne C, Waring L, McDonald RA, Delahay R, Young A. Age-related declines in immune response in a wild mammal are unrelated to immune cell telomere length. Proc Biol Sci 2016; 283:20152949. [PMID: 26888036 PMCID: PMC4810837 DOI: 10.1098/rspb.2015.2949] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Senescence has been hypothesized to arise in part from age-related declines in immune performance, but the patterns and drivers of within-individual age-related changes in immunity remain virtually unexplored in natural populations. Here, using a long-term epidemiological study of wild European badgers (Meles meles), we (i) present evidence of a within-individual age-related decline in the response of a key immune-signalling cytokine, interferon-gamma (IFNγ), to ex vivo lymphocyte stimulation, and (ii) investigate three putative drivers of individual variation in the rate of this decline (sex, disease and immune cell telomere length; ICTL). That the within-individual rate of age-related decline markedly exceeded that at the population level suggests that individuals with weaker IFNγ responses are selectively lost from this population. IFNγ responses appeared to decrease with the progression of bovine tuberculosis infection (independent of age) and were weaker among males than females. However, neither sex nor disease influenced the rate of age-related decline in IFNγ response. Similarly, while ICTL also declines with age, variation in ICTL predicted neither among- nor within-individual variation in IFNγ response. Our findings provide evidence of within-individual age-related declines in immune performance in a wild mammal and highlight the likely complexity of the mechanisms that generate them.
Collapse
Affiliation(s)
- Christopher Beirne
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Laura Waring
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire GL10 3UJ, UK
| | - Robbie A McDonald
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Richard Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire GL10 3UJ, UK
| | - Andrew Young
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| |
Collapse
|
24
|
Hammers M, Komdeur J, Kingma SA, Hutchings K, Fairfield EA, Gilroy DL, Richardson DS. Age-specific haemosporidian infection dynamics and survival in Seychelles warblers. Sci Rep 2016; 6:29720. [PMID: 27431430 PMCID: PMC4949462 DOI: 10.1038/srep29720] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 06/22/2016] [Indexed: 11/09/2022] Open
Abstract
Parasites may severely impact the fitness and life-history of their hosts. After infection, surviving individuals may suppress the growth of the parasite, or completely clear the infection and develop immunity. Consequently, parasite prevalence is predicted to decline with age. Among elderly individuals, immunosenescence may lead to a late-life increase in infection prevalence. We used a 21-year longitudinal dataset from one population of individually-marked Seychelles warblers (Acrocephalus sechellensis) to investigate age-dependent prevalence of the GRW1 strain of the intracellular protozoan blood parasite Haemoproteus nucleocondensus and whether infections with this parasite affect age-dependent survival. We analyzed 2454 samples from 1431 individuals and found that H. nucleocondensus infections could rarely be detected in nestlings. Prevalence increased strongly among fledglings and peaked among older first year birds. Prevalence was high among younger adults and declined steeply until ca 4 years of age, after which it was stable. Contrary to expectations, H. nucleocondensus prevalence did not increase among elderly individuals and we found no evidence that annual survival was lower in individuals suffering from an infection. Our results suggest that individuals clear or suppress infections and acquire immunity against future infections, and provide no evidence for immunosenescence nor an impact of chronic infections on survival.
Collapse
Affiliation(s)
- Martijn Hammers
- Behavioural and Physiological Ecology, GELIFES, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands.,Theoretical Research in Evolutionary Life Sciences, GELIFES, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands
| | - Jan Komdeur
- Behavioural and Physiological Ecology, GELIFES, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands
| | - Sjouke A Kingma
- Behavioural and Physiological Ecology, GELIFES, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands.,Theoretical Research in Evolutionary Life Sciences, GELIFES, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands
| | - Kimberly Hutchings
- Behavioural and Physiological Ecology, GELIFES, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, NR4 7TJ, UK
| | - Eleanor A Fairfield
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, NR4 7TJ, UK
| | - Danielle L Gilroy
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, NR4 7TJ, UK
| | - David S Richardson
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, NR4 7TJ, UK.,Nature Seychelles, Roche Caiman, Mahé, Republic of Seychelles
| |
Collapse
|
25
|
Charruau P, Johnston RA, Stahler DR, Lea A, Snyder-Mackler N, Smith DW, vonHoldt BM, Cole SW, Tung J, Wayne RK. Pervasive Effects of Aging on Gene Expression in Wild Wolves. Mol Biol Evol 2016; 33:1967-78. [PMID: 27189566 DOI: 10.1093/molbev/msw072] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Gene expression levels change as an individual ages and responds to environmental conditions. With the exception of humans, such patterns have principally been studied under controlled conditions, overlooking the array of developmental and environmental influences that organisms encounter under conditions in which natural selection operates. We used high-throughput RNA sequencing (RNA-Seq) of whole blood to assess the relative impacts of social status, age, disease, and sex on gene expression levels in a natural population of gray wolves (Canis lupus). Our findings suggest that age is broadly associated with gene expression levels, whereas other examined factors have minimal effects on gene expression patterns. Further, our results reveal evolutionarily conserved signatures of senescence, such as immunosenescence and metabolic aging, between wolves and humans despite major differences in life history and environment. The effects of aging on gene expression levels in wolves exhibit conservation with humans, but the more rapid expression differences observed in aging wolves is evolutionarily appropriate given the species' high level of extrinsic mortality due to intraspecific aggression. Some expression changes that occur with age can facilitate physical age-related changes that may enhance fitness in older wolves. However, the expression of these ancestral patterns of aging in descendant modern dogs living in highly modified domestic environments may be maladaptive and cause disease. This work provides evolutionary insight into aging patterns observed in domestic dogs and demonstrates the applicability of studying natural populations to investigate the mechanisms of aging.
Collapse
Affiliation(s)
- Pauline Charruau
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles
| | - Rachel A Johnston
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles
| | - Daniel R Stahler
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park
| | | | | | - Douglas W Smith
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park
| | | | - Steven W Cole
- Department of Medicine, University of California, Los Angeles Cousins Center for Psychoneuroimmunology, Semel Institute, University of California, Los Angeles
| | - Jenny Tung
- Department of Biology, Duke University Department of Evolutionary Anthropology, Duke University
| | - Robert K Wayne
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles
| |
Collapse
|
26
|
Senescence in the wild: Insights from a long-term study on Seychelles warblers. Exp Gerontol 2015; 71:69-79. [DOI: 10.1016/j.exger.2015.08.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/28/2015] [Accepted: 08/31/2015] [Indexed: 11/23/2022]
|
27
|
Demas GE, Carlton ED. Ecoimmunology for psychoneuroimmunologists: Considering context in neuroendocrine-immune-behavior interactions. Brain Behav Immun 2015; 44:9-16. [PMID: 25218837 PMCID: PMC4275338 DOI: 10.1016/j.bbi.2014.09.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 08/26/2014] [Accepted: 09/01/2014] [Indexed: 02/06/2023] Open
Abstract
The study of immunity has become an important area of investigation for researchers in a wide range of areas outside the traditional discipline of immunology. For the last several decades, psychoneuroimmunology (PNI) has strived to identify key interactions among the nervous, endocrine and immune systems and behavior. More recently, the field of ecological immunology (ecoimmunology) has been established within the perspectives of ecology and evolutionary biology, sharing with PNI an appreciation of the environmental influences on immune function. The primary goal of ecoimmunology is to understand immune function within a broadly integrative, organismal context, typically from an ultimate, evolutionary perspective. To accomplish this ecoimmunology, like PNI, has become a broadly integrative field of investigation, combining diverse approaches from evolution and ecology to endocrinology and neurobiology. The disciplines of PNI and ecoimmunology, with their unique yet complementary perspectives and methodologies, have much to offer one another. Researchers in both fields, however, remain largely unaware of each other's findings despite attempts at integration. The goal of this review is to share with psychoneuroimmunologists and other mechanistically-oriented researchers some of the core concepts and principles, as well as relevant recent findings, within ecoimmunology with the hope that this information will prove relevant to their own research programs. More broadly, our goal is to attempt to integrate both the proximate and ultimate perspectives offered by PNI and ecoimmunology respectively into a common theoretical framework for understanding neuro-endocrine-immune interactions and behavior in a larger ecological, evolutionary context.
Collapse
Affiliation(s)
- Gregory E Demas
- Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA.
| | - Elizabeth D Carlton
- Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA
| |
Collapse
|
28
|
Shattuck EC, Muehlenbein MP. Human sickness behavior: Ultimate and proximate explanations. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2015; 157:1-18. [DOI: 10.1002/ajpa.22698] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 12/27/2014] [Accepted: 12/28/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Eric C. Shattuck
- Evolutionary Physiology and Ecology Laboratory; Department of Anthropology; Indiana University; Bloomington IN
| | - Michael P. Muehlenbein
- Evolutionary Physiology and Ecology Laboratory; Department of Anthropology; Indiana University; Bloomington IN
| |
Collapse
|
29
|
Froy H, Lewis S, Catry P, Bishop CM, Forster IP, Fukuda A, Higuchi H, Phalan B, Xavier JC, Nussey DH, Phillips RA. Age-related variation in foraging behaviour in the wandering albatross at South Georgia: no evidence for senescence. PLoS One 2015; 10:e0116415. [PMID: 25574995 PMCID: PMC4289070 DOI: 10.1371/journal.pone.0116415] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 12/09/2014] [Indexed: 11/18/2022] Open
Abstract
Age-related variation in demographic rates is now widely documented in wild vertebrate systems, and has significant consequences for population and evolutionary dynamics. However, the mechanisms underpinning such variation, particularly in later life, are less well understood. Foraging efficiency is a key determinant of fitness, with implications for individual life history trade-offs. A variety of faculties known to decline in old age, such as muscular function and visual acuity, are likely to influence foraging performance. We examine age-related variation in the foraging behaviour of a long-lived, wide-ranging oceanic seabird, the wandering albatross Diomedea exulans. Using miniaturised tracking technologies, we compared foraging trip characteristics of birds breeding at Bird Island, South Georgia. Based on movement and immersion data collected during the incubation phase of a single breeding season, and from extensive tracking data collected in previous years from different stages of the breeding cycle, we found limited evidence for age-related variation in commonly reported trip parameters, and failed to detect signs of senescent decline. Our results contrast with the limited number of past studies that have examined foraging behaviour in later life, since these have documented changes in performance consistent with senescence. This highlights the importance of studies across different wild animal populations to gain a broader perspective on the processes driving variation in ageing rates.
Collapse
Affiliation(s)
- Hannah Froy
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
- British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom
- * E-mail:
| | - Sue Lewis
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Paulo Catry
- Marine and Environmental Sciences Centre, ISPA—Instituto Universitário, Lisbon, Portugal
| | - Charles M. Bishop
- School of Biological Sciences, Bangor University, Bangor, United Kingdom
| | - Isaac P. Forster
- Australian Antarctic Division, University of Tasmania, Kingston, Australia
| | | | | | - Ben Phalan
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Jose C. Xavier
- British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom
- Marine and Environmental Sciences Centre, University of Coimbra, Coimbra, Portuga
| | - Daniel H. Nussey
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Richard A. Phillips
- British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom
| |
Collapse
|
30
|
Beirne C, Delahay R, Hares M, Young A. Age-related declines and disease-associated variation in immune cell telomere length in a wild mammal. PLoS One 2014; 9:e108964. [PMID: 25268841 PMCID: PMC4182606 DOI: 10.1371/journal.pone.0108964] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 09/05/2014] [Indexed: 11/18/2022] Open
Abstract
Immunosenescence, the deterioration of immune system capability with age, may play a key role in mediating age-related declines in whole-organism performance, but the mechanisms that underpin immunosenescence are poorly understood. Biomedical research on humans and laboratory models has documented age and disease related declines in the telomere lengths of leukocytes ('immune cells'), stimulating interest their having a potentially general role in the emergence of immunosenescent phenotypes. However, it is unknown whether such observations generalise to the immune cell populations of wild vertebrates living under ecologically realistic conditions. Here we examine longitudinal changes in the mean telomere lengths of immune cells in wild European badgers (Meles meles). Our findings provide the first evidence of within-individual age-related declines in immune cell telomere lengths in a wild vertebrate. That the rate of age-related decline in telomere length appears to be steeper within individuals than at the overall population level raises the possibility that individuals with short immune cell telomeres and/or higher rates of immune cell telomere attrition may be selectively lost from this population. We also report evidence suggestive of associations between immune cell telomere length and bovine tuberculosis infection status, with individuals detected at the most advanced stage of infection tending to have shorter immune cell telomeres than disease positive individuals. While male European badgers are larger and show higher rates of annual mortality than females, we found no evidence of a sex difference in either mean telomere length or the average rate of within-individual telomere attrition with age. Our findings lend support to the view that age-related declines in the telomere lengths of immune cells may provide one potentially general mechanism underpinning age-related declines in immunocompetence in natural populations.
Collapse
Affiliation(s)
- Christopher Beirne
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall, United Kingdom
| | - Richard Delahay
- National Wildlife Management Centre, Animal Health and Veterinary Laboratories Agency, Woodchester Park, Nympsfield, Gloucestershire, United Kingdom
| | - Michelle Hares
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall, United Kingdom
| | - Andrew Young
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall, United Kingdom
- * E-mail:
| |
Collapse
|
31
|
Faragher R, Frasca D, Remarque E, Pawelec G. Better immunity in later life: a position paper. AGE (DORDRECHT, NETHERLANDS) 2014; 36:9619. [PMID: 24532368 PMCID: PMC4082593 DOI: 10.1007/s11357-014-9619-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 01/12/2014] [Indexed: 06/03/2023]
Abstract
Ageing is the greatest challenge that health-care systems will have to deal with this century. This is because a wide spectrum of pathological impairments emerge in the later part of the human life course which sharply increase mortality and reduce quality of life. Dysfunction of the immune system with advancing age is of crucial importance to the development of disability in later life and finally death. Understanding immune ageing, immunosenescence, has long been recognised as an essential prerequisite for the delivery of effective interventions which will improve late life health. Ten years ago, the ImAginE consortium undertook a broad ranging series of projects which added significantly to our understanding of how fundamental ageing mechanisms drove immune decline. In the decade which followed, abundant evidence has accumulated from nonhuman model systems that ageing results from the progressive operation of a relatively few common processes which act across the major organ systems. These advances in fundamental understanding both allow better clarification of the potential cross-system dysregulation that occurs in ageing and open new avenues for intervention. Over the course of a 2-day workshop, the original ImAginE participants have considered these issues and present some suggestions for current priority areas in immunosenescence.
Collapse
Affiliation(s)
- Richard Faragher
- />School of Pharmacy & Biomolecular Science, University of Brighton, Huxley Building, Brighton, UK
| | - Daniela Frasca
- />Department of Microbiology and Immunology, University of Miami, Room 3146A, Rosenstiel Medical Science Building, Miami, FL USA
| | - Edmond Remarque
- />Department of Parasitology, Biomedical Primate Research Centre, PO Box 3306, 2280 GH Rijswijk, The Netherlands
| | - Graham Pawelec
- />Tübingen Ageing and Tumour Immunology Group (TATI) Section for Transplantation Immunology and Immunohaematology ZMF, University of Tübingen, Waldhörnlestr. 22, 72072 Tübingen, Germany
| | | |
Collapse
|
32
|
Maia JP, Harris DJ, Carranza S, Gómez-Díaz E. A comparison of multiple methods for estimating parasitemia of hemogregarine hemoparasites (apicomplexa: adeleorina) and its application for studying infection in natural populations. PLoS One 2014; 9:e95010. [PMID: 24743340 PMCID: PMC3990604 DOI: 10.1371/journal.pone.0095010] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 03/21/2014] [Indexed: 11/19/2022] Open
Abstract
Identifying factors influencing infection patterns among hosts is critical for our understanding of the evolution and impact of parasitism in natural populations. However, the correct estimation of infection parameters depends on the performance of detection and quantification methods. In this study, we designed a quantitative PCR (qPCR) assay targeting the 18 S rRNA gene to estimate prevalence and intensity of Hepatozoon infection and compared its performance with microscopy and PCR. Using qPCR, we also compared various protocols that differ in the biological source and the extraction methods. Our results show that the qPCR approach on DNA extracted from blood samples, regardless of the extraction protocol, provided the most sensitive estimates of Hepatozoon infection parameters; while allowed us to differentiate between mixed infections of Adeleorinid (Hepatozoon) and Eimeriorinid (Schellackia and Lankesterella), based on the analysis of melting curves. We also show that tissue and saline methods can be used as low-cost alternatives in parasitological studies. The next step was to test our qPCR assay in a biological context, and for this purpose we investigated infection patterns between two sympatric lacertid species, which are naturally infected with apicomplexan hemoparasites, such as the genera Schellackia (Eimeriorina) and Hepatozoon (Adeleorina). From a biological standpoint, we found a positive correlation between Hepatozoon intensity of infection and host body size within each host species, being significantly higher in males, and higher in the smaller sized host species. These variations can be associated with a number of host intrinsic factors, like hormonal and immunological traits, that require further investigation. Our findings are relevant as they pinpoint the importance of accounting for methodological issues to better estimate infection in parasitological studies, and illustrate how between-host factors can influence parasite distributions in sympatric natural populations.
Collapse
Affiliation(s)
- João P. Maia
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, Universidade do Porto, Campus Agrário de Vairão, Vairão, Vila do Conde, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Spain
- * E-mail: (JPM); (EGD)
| | - D. James Harris
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, Universidade do Porto, Campus Agrário de Vairão, Vairão, Vila do Conde, Portugal
| | - Salvador Carranza
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Spain
| | - Elena Gómez-Díaz
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Spain
- * E-mail: (JPM); (EGD)
| |
Collapse
|
33
|
Maizels RM, Nussey DH. Into the wild: digging at immunology's evolutionary roots. Nat Immunol 2013; 14:879-83. [PMID: 23959175 DOI: 10.1038/ni.2643] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The two pillars of modern immunology have been man and mouse; in both settings, investigators seek to reduce complexity and control environmental conditions. However, the world outside the laboratory is immensely variable; this is not 'noise' but represents the genetic and environmental framework in which the immune system evolved and functions. Placing the ever-growing understanding of immunological mechanisms in wider real-world contexts is a massive but fundamentally important challenge.
Collapse
Affiliation(s)
- Rick M Maizels
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, UK.
| | | |
Collapse
|
34
|
Romano A, Rubolini D, Ambrosini R, Saino N. Early exposure to a bacterial endotoxin may cause breeding failure in a migratory bird. ETHOL ECOL EVOL 2013. [DOI: 10.1080/03949370.2013.800912] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
35
|
Molnár O, Bajer K, Mészáros B, Török J, Herczeg G. Negative correlation between nuptial throat colour and blood parasite load in male European green lizards supports the Hamilton-Zuk hypothesis. Naturwissenschaften 2013; 100:551-8. [PMID: 23644520 DOI: 10.1007/s00114-013-1051-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 01/09/2023]
Abstract
During female mate choice, conspicuous male sexual signals are used to infer male quality and choose the best sire for the offspring. The theory of parasite-mediated sexual selection (Hamilton-Zuk hypothesis) presumes that parasite infection can influence the elaboration of sexual signals: resistant individuals can invest more energy into signal expression and thus advertise their individual quality through signal intensity. By preferring these males, females can provide resistance genes for their offspring. Previous research showed that nuptial throat colour of male European green lizard, Lacerta viridis, plays a role in both inter- and intrasexual selections as a condition-dependent multiple signalling system. The aim of this study was to test the predictions of the Hamilton-Zuk hypothesis on male European green lizards. By blood sampling 30 adult males during the reproductive season, we found members of the Haemogregarinidae family in all but one individual (prevalence = 96%). The infection intensity showed strong negative correlation with the throat and belly colour brightness in line with the predictions of the Hamilton-Zuk hypothesis. In addition, we found other correlations between infection intensity and other fitness-related traits, suggesting that parasite load has a remarkable effect on individual fitness. This study shows that throat patch colour of the European green lizards not only is a multiple signalling system but also possibly acts as an honest sexual signal of health state in accordance with the Hamilton-Zuk hypothesis.
Collapse
Affiliation(s)
- Orsolya Molnár
- Department of Biological Sciences, Life Sciences Center, Dartmouth College, 78 College Street, Hanover, NH 03755, USA.
| | | | | | | | | |
Collapse
|
36
|
Guerreiro R, Besson AA, Bellenger J, Ragot K, Lizard G, Faivre B, Sorci G. Correlational selection on pro- and anti-inflammatory effectors. Evolution 2013; 66:3615-23. [PMID: 23002997 DOI: 10.1111/j.1558-5646.2012.01708.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Parasites impose a permanent threat for hosts. As a consequence, immune defenses are important for host fitness. However, the immune response can also produce self-damage and impair host fitness if not properly regulated. Effectors that up- and downregulate the immune response should, therefore, evolve in concert, and be under the action of correlational selection. To address this issue, we assessed the shape of the selection operating on pro- and anti-inflammatory effectors following an inflammatory challenge in laboratory mice.We found that selection acts on the combination of these two traits as individuals that produced large amount of pro-inflammatory cytokines could achieve relatively high fitness (survival) only if also producing a large amount of anti-inflammatory effectors. To our knowledge, this is the first study providing evidence for correlational selection on immunity.
Collapse
Affiliation(s)
- Romain Guerreiro
- Biogéosciences, CNRS UMR 6282, Universite´ de Bourgogne, 6 Bd Gabriel, 21000 Dijon, France.
| | | | | | | | | | | | | |
Collapse
|
37
|
Nussey DH, Froy H, Lemaitre JF, Gaillard JM, Austad SN. Senescence in natural populations of animals: widespread evidence and its implications for bio-gerontology. Ageing Res Rev 2013; 12:214-25. [PMID: 22884974 PMCID: PMC4246505 DOI: 10.1016/j.arr.2012.07.004] [Citation(s) in RCA: 404] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/24/2012] [Accepted: 07/30/2012] [Indexed: 10/28/2022]
Abstract
That senescence is rarely, if ever, observed in natural populations is an oft-quoted fallacy within bio-gerontology. We identify the roots of this fallacy in the otherwise seminal works of Medawar and Comfort, and explain that under antagonistic pleiotropy or disposable soma explanations for the evolution of senescence there is no reason why senescence cannot evolve to be manifest within the life expectancies of wild organisms. The recent emergence of long-term field studies presents irrefutable evidence that senescence is commonly detected in nature. We found such evidence in 175 different animal species from 340 separate studies. Although the bulk of this evidence comes from birds and mammals, we also found evidence for senescence in other vertebrates and insects. We describe how high-quality longitudinal field data allow us to test evolutionary explanations for differences in senescence between the sexes and among traits and individuals. Recent studies indicate that genes, prior environment and investment in growth and reproduction influence aging rates in the wild. We argue that - with the fallacy that wild animals do not senesce finally dead and buried - collaborations between bio-gerontologists and field biologists can begin to test the ecological generality of purportedly 'public' mechanisms regulating aging in laboratory models.
Collapse
Affiliation(s)
- Daniel H Nussey
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, UK.
| | | | | | | | | |
Collapse
|
38
|
Ashley NT, Weil ZM, Nelson RJ. Inflammation: Mechanisms, Costs, and Natural Variation. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2012. [DOI: 10.1146/annurev-ecolsys-040212-092530] [Citation(s) in RCA: 220] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Noah T. Ashley
- Department of Biology, Western Kentucky University, Bowling Green, Kentucky 42101;
| | - Zachary M. Weil
- Department of Neuroscience, Wexner College of Medicine, Ohio State University, Columbus, Ohio 43210; ,
| | - Randy J. Nelson
- Department of Neuroscience, Wexner College of Medicine, Ohio State University, Columbus, Ohio 43210; ,
| |
Collapse
|
39
|
Zimmerman LM, Clairardin SG, Paitz RT, Hicke JW, LaMagdeleine KA, Vogel LA, Bowden RM. Humoral immune responses are maintained with age in a long-lived ectotherm, the red-eared slider turtle. ACTA ACUST UNITED AC 2012; 216:633-40. [PMID: 23077164 DOI: 10.1242/jeb.078832] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Aging is typically associated with a decrease in immune function. However, aging does not affect each branch of the immune system equally. Because of these varying effects of age on immune responses, aging could affect taxa differently based on how the particular taxon employs its resources towards different components of immune defense. An example of this is found in the humoral immune system. Specific responses tend to decrease with age while non-specific, natural antibody responses increase with age. Compared with mammals, reptiles of all ages have a slower and less robust humoral immune system. Therefore, they may invest more in non-specific responses and thus avoid the negative consequences of age on the immune system. We examined how the humoral immune system of reptiles is affected by aging and investigated the roles of non-specific, natural antibody responses and specific responses by examining several characteristics of antibodies against lipopolysaccharide (LPS) in the red-eared slider turtle. We found very little evidence of immunosenescence in the humoral immune system of the red-eared slider turtle, Trachemys scripta, which supports the idea that non-specific, natural antibody responses are an important line of defense in reptiles. Overall, this demonstrates that a taxon's immune strategy can influence how the immune system is affected by age.
Collapse
Affiliation(s)
- Laura M Zimmerman
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA.
| | | | | | | | | | | | | |
Collapse
|
40
|
Nussey DH, Watt K, Pilkington JG, Zamoyska R, McNeilly TN. Age-related variation in immunity in a wild mammal population. Aging Cell 2012; 11:178-80. [PMID: 22107028 PMCID: PMC3397677 DOI: 10.1111/j.1474-9726.2011.00771.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Age-related changes in immunity are well documented in humans and laboratory mammals. Using blood samples collected from wild Soay sheep, we show that pronounced differences in T-cell subsets and inflammatory markers amongst age classes are also evident under natural conditions. These shifts parallel those observed in mammals experiencing protected environments. We found progressive declines in the proportion of naïve CD4 T cells with age, a precipitous drop in γδ T cells after the second year of life and an increase in acute phase protein levels amongst geriatric sheep. Our findings suggest immune aging patterns observed in laboratory and domestic mammals may generalize to more complex, challenging environments and could have fitness costs under natural conditions.
Collapse
Affiliation(s)
- Daniel H. Nussey
- Centre for Immunity, Infection and Evolution
- Institute of Evolutionary Biology
| | | | | | - Rose Zamoyska
- Centre for Immunity, Infection and Evolution
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh
| | - Tom N. McNeilly
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian, UK
| |
Collapse
|