Inflammation in response to phytohemagglutinin injection in the Talas tuco-tuco (Ctenomys talarum): implications for the estimation of immunocompetence in natural populations of wild rodents

2014 ◽  
Vol 92 (8) ◽  
pp. 689-697 ◽  
Author(s):  
J.L. Merlo ◽  
A.P. Cutrera ◽  
R.R. Zenuto
Keyword(s):  
Skin Test ◽  
T Lymphocyte ◽  
Evolutionary Biology ◽  
Natural Populations ◽  
Wild Populations ◽  
Wild Rodents ◽  
Subterranean Rodent ◽  
Ctenomys Talarum ◽  
Lymphocyte Activity ◽  
Pha Skin Test

The immunological variation in wild populations and its relation to life-history traits has recently become a central topic in the field of evolutionary biology, considering the critical contribution of immunity to an individual’s fitness. A common technique used by ecologists to estimate immunocompetence in wild populations is the phytohemagglutinin (PHA) – skin test. In this test, the degree of local swelling triggered by PHA is usually considered an estimate of T-lymphocyte activity, although there is an ongoing debate regarding this interpretation. Here, we coupled the PHA–skin test with a histological analysis to examine the temporal development of the cell-mediated response in the subterranean rodent Talas tuco-tuco (Ctenomys talarum Thomas, 1898). The inflammation response involved lymphocytes, neutrophils, eosinophils, and macrophages at the site of injection, achieving an increase of total leukocytes from 12 to 48 h after injection. However, the abundance of any of the leukocytes observed did not correlate with the degree of swelling at any time studied, suggesting that caution should be taken when interpreting the results of the PHA-induced swelling response. Particularly, the magnitude of macroscopic swelling should not be considered a priori as indicative of T-lymphocyte activity in wild-caught rodents. Our results highlight the importance of avoiding oversimplified approaches to measuring immunocompetence.

scholarly journals Effects of physical impairments on fitness correlates of the white-footed mouse, Peromyscus leucopus

2021 ◽  
Vol 288 (1962) ◽  
Author(s):  
Francesca I. Rubino ◽  
Kelly Oggenfuss ◽  
Richard S. Ostfeld
Keyword(s):  
Body Mass ◽  
Evolutionary Biology ◽  
Ixodes Scapularis ◽  
Peromyscus Leucopus ◽  
Mass Movement ◽  
Natural Populations ◽  
Home Ranges ◽  
Wild Populations ◽  
Physical Impairments ◽  
White Footed Mouse

Physical impairments are widely assumed to reduce the viability of individual animals, but their impacts on individuals within natural populations of vertebrates are rarely quantified. By monitoring wild populations of white-footed mice over 26 years, we assessed whether missing or deformed limbs, tail or eyes influenced the survival, body mass, movement and ectoparasite burden of their bearers. Of the 27 244 individuals monitored, 543 (2%) had visible physical impairments. Persistence times (survival) were similar between mice with and without impairments. Mice with eye and tail impairments had 5% and 6% greater mass, respectively, than unimpaired mice. Mice with tail impairments had larger home ranges than did unimpaired mice. Burdens of black-legged ticks ( Ixodes scapularis ) were higher among mice with tail and limb impairments while burdens of bot fly larvae ( Cuterebra ) were higher among mice with cataracts compared to mice without impairments. Our findings do not support the presupposition that physical impairments reduce viability in their bearers and are inconsistent with the devaluation of impaired individuals that pervaded early thinking in evolutionary biology.

scholarly journals Genetic analysis of medfly populations in an area of sterile insect technique applications

2021 ◽  
Author(s):  
Rubén Sancho ◽  
Ana Guillem-Amat ◽  
Elena López-Errasquín ◽  
Lucas Sánchez ◽  
Félix Ortego ◽  
...  
Keyword(s):  
Genetic Markers ◽  
Sterile Insect Technique ◽  
Ceratitis Capitata ◽  
Natural Populations ◽  
Low Frequency ◽  
Fruit Fly ◽  
Wild Populations ◽  
Genetic Sexing ◽  
Environmental Implications ◽  
Genetic Sexing Strains

AbstractThe sterile insect technique (SIT) is widely used in integrated pest management programs for the control of the Mediterranean fruit fly (medfly), Ceratitis capitata. The genetic interactions between the released individuals from the genetic sexing strains (GSS), used for SIT applications worldwide, and wild individuals have not been studied. Under the hypothesis that a number of Vienna GSS individuals released to the field might not be completely sterile and may produce viable offspring, we have analyzed medfly Spanish field populations to evaluate the presence of Vienna strain genetic markers. To this goal, we have used contrasted nuclear and mitochondrial genetic markers, and two novel sets of nuclear polymorphisms with the potential to be markers to discriminate between Vienna and wild individuals. Nuclear Vienna markers located on the 5th chromosome of Vienna males have been found in 2.2% (19 from 875) of the Spanish wild medfly females captured at the area where SIT is applied. In addition, a female-inherited mitochondrial Vienna marker has been found in two from the 19 females showing nuclear Vienna markers. The detection of several of these markers in single individuals represents evidence of the introgression of Vienna strain into natural populations. However, alternative explanations as their presence at low frequency in wild populations in the studied areas cannot be fully discarded. The undesired release of non-fully sterile irradiated GSS individuals into the field and their interactions with wild flies, and the potential environmental implications should be taken into account in the application of the SIT.

DNA fingerprinting reveals polygyny in the subterranean rodent Ctenomys talarum

1999 ◽  
Vol 8 (9) ◽  
pp. 1529-1532 ◽  
Author(s):  
Roxana R. Zenuto ◽  
Eileen A. Lacey ◽  
Cristina Busch
Keyword(s):  
Dna Fingerprinting ◽  
Subterranean Rodent ◽  
Ctenomys Talarum

Evolution of stickleback spines through independent cis-regulatory changes at HOXDB

2021 ◽  
Author(s):  
Julia I Wucherpfennig ◽  
Timothy R Howes ◽  
Jessica N Au ◽  
Eric H Au ◽  
Garrett A Roberts Kingman ◽  
...  
Keyword(s):  
Gene Expression ◽  
Evolutionary Biology ◽  
Gasterosteus Aculeatus ◽  
Molecular Mechanisms ◽  
Wild Populations ◽  
Gene Variation ◽  
Regulatory Changes ◽  
Fundamental Goal ◽  
Apeltes Quadracus ◽  
Genetic Mechanisms

Understanding the genetic mechanisms leading to new traits is a fundamental goal of evolutionary biology. We show that HOXDB regulatory changes have been used repeatedly in different stickleback fish species to alter the length and number of bony dorsal spines. In Gasterosteus aculeatus, a variant HOXDB allele is genetically linked to shortening an existing spine and adding a spine. In Apeltes quadracus, a variant allele is associated with lengthening an existing spine and adding a spine. The alleles alter the same conserved non-coding HOXDB enhancer by diverse molecular mechanisms, including SNPs, deletions, and transposable element insertions. The independent cis-acting regulatory changes are linked to anterior expansion or contraction of HOXDB expression. Our findings support the long-standing hypothesis that natural Hox gene variation underlies key morphological patterning changes in wild populations and illustrate how different mutational mechanisms affecting the same region may produce opposite gene expression changes with similar phenotypic outcomes.

An ecological explanation for hyperallometric scaling of reproduction

2021 ◽  
Author(s):  
Tomos Potter ◽  
Anja Felmy
Keyword(s):  
Body Size ◽  
Reproductive Output ◽  
Resource Competition ◽  
Natural Populations ◽  
Scaling Exponent ◽  
Wild Populations ◽  
Wet Season ◽  
Size Dependent ◽  
In The Wild ◽  
The Relationship

AbstractIn wild populations, large individuals have disproportionately higher reproductive output than smaller individuals. We suggest an ecological explanation for this observation: asymmetry within populations in rates of resource assimilation, where greater assimilation causes both increased reproduction and body size. We assessed how the relationship between size and reproduction differs between wild and lab-reared Trinidadian guppies. We show that (i) reproduction increased disproportionately with body size in the wild but not in the lab, where effects of resource competition were eliminated; (ii) in the wild, the scaling exponent was greatest during the wet season, when resource competition is strongest; and (iii) detection of hyperallometric scaling of reproduction is inevitable if individual differences in assimilation are ignored. We propose that variation among individuals in assimilation – caused by size-dependent resource competition, niche expansion, and chance – can explain patterns of hyperallometric scaling of reproduction in natural populations.

Abstract 425: Lycopene Modulates T Lymphocyte Function by Modulating Th1 Responses and Treg Lymphocyte Population

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Lynsey M Mills ◽  
Heather Wilson ◽  
Frank Thies
Keyword(s):  
T Lymphocyte ◽  
T Regulatory Cells ◽  
Mononuclear Cells ◽  
T Cell Subsets ◽  
Lymphocyte Function ◽  
T Helper ◽  
T Helper 1 ◽  
Peripheral Blood Mononuclear ◽  
Lymphocyte Activity ◽  
Ifn Γ

Increased lycopene intake might have cardiovascular benefits, potentially through anti-inflammatory mechanisms. We recently showed that lycopene can influence lymphocyte activity by modulating processes involved in early cellular activation. T lymphocytes comprise different subsets, T cytotoxic, T helper 1 (Th1), T helper 2 (Th2) and T regulatory cells (Treg). We aimed to determine whether lycopene could specifically modulate T-cell subsets function and activity. Peripheral blood mononuclear cells from 11 healthy adults were cultured for 18hr to 60h in the presence of lycopene-enriched liposomes (0-1.18μg lycopene/ml) with or without mitogens. The secretion of cytokines representative of Th1,Th2 and Treg activities were measured by ELISA (IL-2, IL-1β, IL-10, IFN-γ and TGF-β) or cytometric bead array (IL-4, IL-10, IL17 and IFN-γ). The population profile of Tc (CD3+/CD8+), Th (CD3+/CD4+), Treg (CD4+/CD25+), and the Treg subsets nTreg (CD4+/CD25+/FoxP3+) and iTreg (CD4+/CD25+/IL-10+) was determined by flow cytometry. After 18h incubation, IL-2 concentration in the medium was significantly reduced (-29%, p=0.001) in the presence of lycopene (1.18μg/mL). Similar effects were observed after 36h and 60h culture for IFN-γ (-23%, p=0.015), Il-10 (-30%, p=0.023), IL-17 (-30%, p=0.019) but not IL-4 or TGF-β. The proportion of Treg cell was also significantly increased by 36% (p=0.001) in the presence of lycopene (1.18μg/mL) compared with non-treated activated cells. Furthermore, the proportions of iTreg cells were significantly increased by after incubation with lycopene while the proportion of nTreg cells decreased (-20.5 %, p=0.049). We conclude that increased lycopene intake may be beneficial against atherogenesis by modulating T lymphocyte function, particularly in relation toTh1 and Treg.

Sign in / Sign up

Export Citation Format

Share Document