Juvenile pathogen exposure affects the presence of personality in adult field crickets

Vitamin A and its derivatives (retinoids) act as potent regulators in many aspects of mammalian reproduction, development, repair, and maintenance of differentiated tissue functioning. Unlike other vitamins, Vitamin A and retinoids, which have hormonal actions, present significant toxicity, which plays roles in clinically relevant situations, such as hypervitaminosis A and retinoic acid ("differentiation") syndrome. Although clinical presentation is conspicuous in states of insufficient or excessive Vitamin A and retinoid concentration, equally relevant effects on host resistance to specific infectious agents, and in the general maintenance of immune homeostasis, may go unnoticed, because their expression requires either pathogen exposure or the presence of inflammatory co-morbidities. There is a vast literature on the roles played by retinoids in the maintenance of a tolerogenic, noninflammatory environment in the gut mucosa, which is considered by many investigators representative of a general role played by retinoids as anti-inflammatory hormones elsewhere. However, in the gut mucosa itself, as well as in the bone marrow and inflammatory sites, context determines whether one observes an anti-inflammatory or proinflammatory action of retinoids. Both interactions between specialized cell populations, and interactions between retinoids and other classes of mediators/regulators, such as cytokines and glucocorticoid hormones, must be considered as important factors contributing to this overall context. We review evidence from recent studies on mucosal immunity, granulocyte biology and respiratory allergy models, highlighting the relevance of these variables as well as their possible contributions to the observed outcomes.

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Impact of Vaccination and Pathogen Exposure Dosage on Shedding Kinetics of Infectious Hematopoietic Necrosis Virus (IHNV) in Rainbow Trout

Journal of Aquatic Animal Health ◽

10.1002/aah.10108 ◽

2020 ◽

Vol 32 (3) ◽

pp. 95-108 ◽

Cited By ~ 1

Author(s):

Darbi R. Jones ◽

Barbara J. Rutan ◽

Andrew R. Wargo

Keyword(s):

Rainbow Trout ◽

Infectious Hematopoietic Necrosis Virus ◽

Necrosis Virus ◽

Infectious Hematopoietic Necrosis ◽

Exposure Dosage ◽

Kinetics Of ◽

Pathogen Exposure

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Immune function during pregnancy varies between ecologically distinct populations

Evolution Medicine and Public Health ◽

10.1093/emph/eoaa022 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 114-128

Author(s):

Carmen Hové ◽

Benjamin C Trumble ◽

Amy S Anderson ◽

Jonathan Stieglitz ◽

Hillard Kaplan ◽

...

Keyword(s):

Leukocyte Count ◽

Total Leukocyte Count ◽

Future Research ◽

Differential Leukocyte Count ◽

Ecological Conditions ◽

Trade Offs ◽

The Usa ◽

Immunological Changes ◽

Fetal Antigens ◽

Pathogen Exposure

Abstract Background and objectives Among placental mammals, females undergo immunological shifts during pregnancy to accommodate the fetus (i.e. fetal tolerance). Fetal tolerance has primarily been characterized within post-industrial populations experiencing evolutionarily novel conditions (e.g. reduced pathogen exposure), which may shape maternal response to fetal antigens. This study investigates how ecological conditions affect maternal immune status during pregnancy by comparing the direction and magnitude of immunological changes associated with each trimester among the Tsimane (a subsistence population subjected to high pathogen load) and women in the USA. Methodology Data from the Tsimane Health and Life History Project (N = 935) and the National Health and Nutrition Examination Survey (N = 1395) were used to estimate population-specific effects of trimester on differential leukocyte count and C-reactive protein (CRP), a marker of systemic inflammation. Results In both populations, pregnancy was associated with increased neutrophil prevalence, reduced lymphocyte and eosinophil count and elevated CRP. Compared to their US counterparts, pregnant Tsimane women exhibited elevated lymphocyte and eosinophil counts, fewer neutrophils and monocytes and lower CRP. Total leukocyte count remained high and unchanged among pregnant Tsimane women while pregnant US women exhibited substantially elevated counts, resulting in overlapping leukocyte prevalence among all third-trimester individuals. Conclusions and implications Our findings indicate that ecological conditions shape non-pregnant immune baselines and the magnitude of immunological shifts during pregnancy via developmental constraints and current trade-offs. Future research should investigate how such flexibility impacts maternal health and disease susceptibility, particularly the degree to which chronic pathogen exposure might dampen inflammatory response to fetal antigens. Lay Summary This study compares immunological changes associated with pregnancy between the Tsimane (an Amazonian subsistence population) and individuals in the USA. Results suggest that while pregnancy enhances non-specific defenses and dampens both antigen-specific immunity and parasite/allergy response, ecological conditions strongly influence immune baselines and the magnitude of shifts during gestation.

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Balancing Selection on Electrophoretic Variation of Phosphoglucose Isomerase in Two Species of Field Cricket: Gryllus veletis and G. pennsylvanicus

Genetics ◽

10.1093/genetics/147.2.609 ◽

1997 ◽

Vol 147 (2) ◽

pp. 609-621

Author(s):

Laura A Katz ◽

Richard G Harrison

Keyword(s):

Balancing Selection ◽

Emergent Property ◽

Phosphoglucose Isomerase ◽

Field Cricket ◽

Nucleotide Variation ◽

Eastern United States ◽

Electrophoretic Variation ◽

Sympatric Populations ◽

Field Crickets ◽

Gryllus Veletis

Two species of crickets, Gryllus veletis and G. pennsylvanicus, share six electrophoretic mobility classes for the enzyme phosphoglucose isomerase (PGI), despite evidence from other genetic markers that the two species are not closely related within eastern North American field crickets. Moreover, the frequencies of the two most common PGI electrophoretic classes (PGI-100 and PGI-65) covary in sympatric populations of these species in the eastern United States, suggesting that PGI may be subject to trans-specific balancing selection. To determine the molecular basis of the electrophoretic variation, we characterized the DNA sequence of the Pgi gene from 29 crickets (15 G. veletis and 14 G. pennsylvanicus). Amino acid substitutions that distinguish the electrophoretic classes are not the same in the two species, and there is no evidence that specific replacement substitutions represent trans-specific polymorphism. In particular, the amino acids that diagnose the PGI-65 allele relative to the PGI-100 allele differ both between G. veletis and G. pennsylvanicus and within G. pennsylvanicus. The heterogeneity among electrophoretic classes that covary in sympatric populations coupled with analysis of patterns of nucleotide variation suggest that Pgi is not evolving neutrally. Instead, the data are consistent with balancing selection operating on an emergent property of the PGI protein.

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