Fitness outcomes in relation to individual variation in constitutive innate immune function

Although crucial for host survival when facing persistent parasite pressure, costly immune functions will inevitably compete for resources with other energetically expensive traits such as reproduction. Optimizing, but not necessarily maximizing, immune function might therefore provide net benefit to overall host fitness. Evidence for associations between fitness and immune function is relatively rare, limiting our potential to understand ultimate fitness costs of immune investment. Here, we assess how measures of constitutive immune function (haptoglobin, natural antibodies, complement activity) relate to subsequent fitness outcomes (survival, reproductive success, dominance acquisition) in a wild passerine ( Malurus coronatus ). Surprisingly, survival probability was not positively linearly predicted by any immune index. Instead, both low and high values of complement activity (quadratic effect) were associated with higher survival, suggesting that different immune investment strategies might reflect a dynamic disease environment. Positive linear relationships between immune indices and reproductive success suggest that individual heterogeneity overrides potential resource reallocation trade-offs within individuals. Controlling for body condition (size-adjusted body mass) and chronic stress (heterophil-lymphocyte ratio) did not alter our findings in a sample subset with available data. Overall, our results suggest that constitutive immune components have limited net costs for fitness and that variation in immune maintenance relates to individual differences more closely.

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No Detectable Trade-Offs Among Immune Function, Fecundity, and Survival via a Juvenile Hormone Analog in the House Cricket

Neotropical Entomology ◽

10.1007/s13744-014-0215-z ◽

2014 ◽

Vol 43 (4) ◽

pp. 357-361 ◽

Cited By ~ 1

Author(s):

A Nava-Sánchez ◽

R Munguía-Steyer ◽

A Córdoba-Aguilar

Keyword(s):

Juvenile Hormone ◽

Immune Function ◽

House Cricket ◽

Juvenile Hormone Analog ◽

Trade Offs ◽

Hormone Analog

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High-Fat Diet and Age-Dependent Effects of IgA-Bearing Cell Populations in the Small Intestinal Lamina Propria in Mice

International Journal of Molecular Sciences ◽

10.3390/ijms22031165 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1165

Author(s):

Yuta Sakamoto ◽

Masatoshi Niwa ◽

Ken Muramatsu ◽

Satoshi Shimo

Keyword(s):

Immune Function ◽

Lamina Propria ◽

High Fat Diet ◽

Immunoglobulin A ◽

Immune Functions ◽

High Fat ◽

Intestinal Villi ◽

Diet Induced Obesity ◽

Obesity And Diabetes

Several studies highlighted that obesity and diabetes reduce immune function. However, changes in the distribution of immunoglobins (Igs), including immunoglobulin-A (IgA), that have an important function in mucosal immunity in the intestinal tract, are unclear. This study aimed to investigate the impaired immune functions in the context of a diet-induced obese murine model via the assessment of the Igs in the intestinal villi. We used mice fed a high-fat diet (HFD) from four to 12 or 20 weeks of age. The distributions of IgA, IgM, and IgG1 were observed by immunohistochemistry. Interestingly, we observed that IgA was immunolocalized in many cells of the lamina propria and that immunopositive cells increased in mice aged 12 to 20 weeks. Notably, mice fed HFD showed a reduced number of IgA-immunopositive cells in the intestinal villi compared to those fed standard chow. Of note, the levels of IgM and IgG1 were also reduced in HFD fed mice. These results provide insights into the impaired mucosal immune function arising from diet-induced obesity and type 2 diabetes.

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Social and endocrine correlates of immune function in meerkats: implications for the immunocompetence handicap hypothesis

Royal Society Open Science ◽

10.1098/rsos.180435 ◽

2018 ◽

Vol 5 (8) ◽

pp. 180435 ◽

Cited By ~ 1

Author(s):

Kendra N. Smyth ◽

Nicholas M. Caruso ◽

Charli S. Davies ◽

Tim H. Clutton-Brock ◽

Christine M. Drea

Keyword(s):

Immune Function ◽

Social Status ◽

Dominant Species ◽

Reproductive Activity ◽

Trade Offs ◽

Endocrine Mechanism ◽

Immunocompetence Handicap Hypothesis ◽

Handicap Hypothesis ◽

Serum Bacteria ◽

Bacteria Killing

Social status can mediate effects on the immune system, with profound consequences for individual health; nevertheless, most investigators of status-related disparities in free-ranging animals have used faecal parasite burdens to proxy immune function in the males of male-dominant species. We instead use direct measures of innate immune function (complement and natural antibodies) to examine status-related immunocompetence in both sexes of a female-dominant species. The meerkat is a unique model for such a study because it is a cooperatively breeding species in which status-related differences are extreme, evident in reproductive skew, morphology, behaviour, communication and physiology, including that dominant females naturally express the greatest total androgen (androstenedione plus testosterone) concentrations. We found that, relative to subordinates, dominant animals had reduced serum bacteria-killing abilities; also, relative to subordinate females, dominant females had reduced haemolytic complement activities. Irrespective of an individual's sex or social status, androstenedione concentrations (but not body condition, age or reproductive activity) negatively predicted concurrent immunocompetence. Thus, dominant meerkats of both sexes are immunocompromised. Moreover, in female meerkats, androstenedione perhaps acting directly or via local conversion, may exert a double-edged effect of promoting dominance and reproductive success at the cost of increased parasitism and reduced immune function. Given the prominent signalling of dominance in female meerkats, these findings may relate to the immunocompetence handicap hypothesis (ICHH); however, our data would suggest that the endocrine mechanism underlying the ICHH need not be mediated solely by testosterone and might explain trade-offs in females, as well as in males.

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Limited Access to Food and Physiological Trade‐Offs in a Long‐Distance Migrant Shorebird. II. Constitutive Immune Function and the Acute‐Phase Response

Physiological and Biochemical Zoology ◽

10.1086/603635 ◽

2009 ◽

Vol 82 (5) ◽

pp. 561-571 ◽

Cited By ~ 41

Author(s):

Deborah M. Buehler ◽

Francisco Encinas‐Viso ◽

Magali Petit ◽

François Vézina ◽

B. Irene Tieleman ◽

...

Keyword(s):

Immune Function ◽

Acute Phase ◽

Acute Phase Response ◽

Phase Response ◽

Long Distance ◽

Limited Access ◽

Trade Offs ◽

Access To Food

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A multiscale approach to balance trade-offs among dam infrastructure, river restoration, and cost

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1807437115 ◽

2018 ◽

Vol 115 (47) ◽

pp. 12069-12074 ◽

Cited By ~ 20

Author(s):

Samuel G. Roy ◽

Emi Uchida ◽

Simone P. de Souza ◽

Ben Blachly ◽

Emma Fox ◽

...

Keyword(s):

New England ◽

River Restoration ◽

Spatial Scales ◽

Dam Removal ◽

The United States ◽

Multiscale Approach ◽

Funding Policy ◽

Net Benefit ◽

Trade Offs ◽

Aging Infrastructure

Aging infrastructure and growing interests in river restoration have led to a substantial rise in dam removals in the United States. However, the decision to remove a dam involves many complex trade-offs. The benefits of dam removal for hazard reduction and ecological restoration are potentially offset by the loss of hydroelectricity production, water supply, and other important services. We use a multiobjective approach to examine a wide array of trade-offs and synergies involved with strategic dam removal at three spatial scales in New England. We find that increasing the scale of decision-making improves the efficiency of trade-offs among ecosystem services, river safety, and economic costs resulting from dam removal, but this may lead to heterogeneous and less equitable local-scale outcomes. Our model may help facilitate multilateral funding, policy, and stakeholder agreements by analyzing the trade-offs of coordinated dam decisions, including net benefit alternatives to dam removal, at scales that satisfy these agreements.

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Market orientation and firm performance: can there be too much of a good thing?

Management Decision ◽

10.1108/md-01-2021-0004 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Vivien Jancenelle ◽

Susan F. Storrud-Barnes ◽

Dominic Buccieri

Keyword(s):

Firm Performance ◽

Market Orientation ◽

Past Research ◽

Good Thing ◽

Annual Reports ◽

Curvilinear Relationship ◽

Computer Assisted ◽

Content Type ◽

Trade Offs ◽

Linear Relationships

PurposePast research has generally purported that market orientation (MO) leads to superior firm performance, despite emerging evidence suggesting that the highest levels of MO are not always rewarded. Drawing on resource-based view and MO literature, the authors posit that too much MO may be as detrimental as too little for firms seeking to achieve better performance, and that moderate MO capabilities may be the most beneficial. Furthermore, the authors propose and test for organizational confidence as a first potential moderator of the MO-performance inverted U-shaped link.Design/methodology/approachThe authors use Computer-Assisted-Text-Analysis (CATA) methodology assess constructs from annual reports matched with a 5-year longitudinal dataset of 2,245 firm-year observations drawn from the S&P 500.FindingsThe results not only support the presence of an inverted U-shaped link between MO and firm performance, but also identify organizational confidence as an important moderator of this newly uncovered curvilinear relationship.Practical implicationsWhen it comes to the effect of MO on firm performance, there can be indeed be “too much of a good thing,” and managers should be aware of the trade-offs that come attached with overcommitting to a MO strategy.Originality/valueThe authors contribute to extant research on the MO–performance link by moving beyond simple linear relationships and identifying an inverted U-shaped relationship between MO and firm performance. This newly found curvilinear relationship may explain and reconcile prior contradicting findings on the benefits of MO. Organizational confidence is also found to trigger a shape-flip of the MO–performance link, thereby suggesting a new boundary condition.

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Activation of an inflammatory response is context-dependent during early development of the California sea lion

Royal Society Open Science ◽

10.1098/rsos.150108 ◽

2015 ◽

Vol 2 (4) ◽

pp. 150108 ◽

Cited By ~ 9

Author(s):

Camila Vera-Massieu ◽

Patrick M. Brock ◽

Carlos Godínez-Reyes ◽

Karina Acevedo-Whitehouse

Keyword(s):

Immune System ◽

Inflammatory Response ◽

Immune Function ◽

Early Development ◽

Body Condition ◽

Sea Lion ◽

California Sea Lion ◽

Trade Offs ◽

Current Infection ◽

Circulating Levels

Variations in immune function can arise owing to trade-offs, that is, the allocation of limited resources among costly competing physiological functions. Nevertheless, there is little information regarding the ontogeny of the immune system within an ecological context, and it is still unknown whether development affects the way in which resources are allocated to different immune effectors. We investigated changes in the inflammatory response during early development of the California sea lion ( Zalophus californianus ) and examined its association with body condition, as a proxy for the availability of energetic resources. We found that the relationship between inflammation and body condition varied according to developmental stage and circulating levels of leucocyte populations, a proxy for current infection. Body condition was related to the magnitude of the inflammatory response during two of the three developmental periods assessed, allowing for the possibility that the availability of pup energetic reserves can limit immune function. For older pups, the ability to mount an inflammatory response was related to their circulating levels of neutrophils and the neutrophil to lymphocyte ratio, implying that the infection status of an individual will influence its ability to respond to a new challenge. Our results suggest that trade-offs may occur within the immune system and highlight the importance of taking into account ontogeny in ecoimmunological studies.

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