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Tomáš Albrecht - One of the best experts on this subject based on the ideXlab platform.

  • Fecal microbiota associated with phytohaemagglutinin-induced immune response in nestlings of a passerine bird
    Ecology and Evolution, 2018
    Co-Authors: Jakub Kreisinger, Lucie Schmiedová, Adéla Petrželková, Oldřich Tomášek, Marie Adamkova, Romana Michalkova, Jean-françois Martin, Tomáš Albrecht
    Abstract:

    The vertebrate gastrointestinal tract is inhabited by a diverse community of bacteria, the so‐called gut microbiota (GM). Research on captive mammalian models has revealed tight mutual interactions between immune functions and GM. However, our knowledge of GM versus immune system interactions in wild populations and nonmammalian species remains poor. Here, we focus on the association between GM community structure and immune response measured via the phytohaemagglutinin (PHA) Skin Swelling test in 12‐day‐old nestlings of a passerine bird, the barn swallow (Hirundo rustica). The PHA test, a widely used method in field ecoimmunology, assesses cell‐mediated immunity. GM structure was inferred based on high‐throughput 16S rRNA sequencing of microbial communities in fecal samples. We did not find any association between PHA response and GM diversity; however, our data revealed that the intensity of PHA response was correlated with differences in GM composition at the whole‐community level. Ten bacterial operational taxonomic units corresponding to both putative commensal and pathogens were identified as drivers of the compositional variation. In conclusion, our study suggests existence of GM versus immune system interactions in a free‐living nonmammalian species, which corresponds with previous research on captive vertebrates.

  • Application of Concanavalin A during immune responsiveness Skin-Swelling tests facilitates measurement interpretation in mammalian ecology.
    Ecology and evolution, 2016
    Co-Authors: Barbora Bílková, Tomáš Albrecht, Milada Chudíčková, Vladimír Holáň, Jaroslav Piálek, Michal Vinkler
    Abstract:

    The Skin-Swelling test is a simple and widespread method used in field ecological research to estimate cellular immune responsiveness in animals. This immunoecological test is based on measuring the magnitude of tissue Swelling response at specific times following subcutaneous application of an experimental pro-inflammatory stimulant. In the vast majority of studies across vertebrate taxa, phytohemagglutinin (PHA) is used as a universal stimulant. Given the complexity of immune response activation pathways of PHA, however, interpretation of test results can be ambiguous. Goal of this study was to improve methodology of the Skin-Swelling test to decrease this ambiguity. Here, we present an alternative protocol aimed at facilitating interpretation of Skin-Swelling data for mammals. Based on previous evidence suggesting that mammalian T cells are readily activated by Concanavalin A (ConA) in vitro, we compared cellular immune responses in vivo to PHA and ConA as an alternative pro-inflammatory stimulant in mice. We measured magnitude of tissue Swelling and compared it with intensity of blood cell infiltration into tissue over a 72-hour interval. Our results corroborate that PHA and ConA show important differences in both dynamics and response amplitude in rodents. ConA induces stronger Swelling with a distinct leukocyte activity pattern and higher pro-inflammatory cytokine (interleukin 6 [IL-6] and interferon gamma[IFN-γ]) expression than PHA during peak response (24-h post-treatment). Furthermore, unlike PHA, magnitude of Swelling was positively associated with cellular activity (number of neutrophils infiltrating tissue) following ConA injection. We conclude that ConA is the more suitable stimulant for Skin-Swelling tests in mammals. This is because of the molecular binding specificity in the two lectins, that is, ConA specifically activates T cells while PHA also triggers erythroagglutination. We propose that ConA be used in all future ecological testing in mammals as it exhibits better performance and its application facilitates immunological interpretation of Skin-Swelling test results.

  • Phytohaemagglutinin Skin-Swelling test in scarlet rosefinch males: low-quality birds respond more strongly
    Animal Behaviour, 2012
    Co-Authors: Michal Vinkler, Jan Schnitzer, Pavel Munclinger, Tomáš Albrecht
    Abstract:

    The phytohaemagglutinin (PHA) Skin-Swelling test is one of the most widely used methods for cell-mediated immunity measurement in immunoecology. Although several studies have investigated the condition-dependent traits associated with the magnitude of cutaneous inflammatory response to PHA, the results concerning signalling of the responsiveness through ornamental traits are still controversial. This is especially true for carotenoid-based feather ornamentation in birds. We therefore examined the linkage between several condition-dependent traits, including the red ornamental coloration of the plumage, and the magnitude of the PHA-induced immune response in scarlet rosefinch, Carpodacus erythrinus, males. Our results show two important aspects of the PHA-induced inflammation in this species. First, histological analysis showed that the Swelling response was dependent on basophil activity. Second, the magnitude of the response (increase in patagium thickness) was associated with individual size, carotenoid-based ornamental coloration and a ptilochronological marker of feather growth at the time of moulting (mean growth bar width), thus mirroring the long-term quality of the individual. The positive linkage between the individual size or mean growth bar width and the PHA response suggests an association between the magnitude of the response and individual metabolic rate. However, as the magnitude of the response was also related negatively to ornament saturation and positively to ornament lightness, our results indicate stronger responsiveness in inferior males. Highly ornamented, healthier individuals recruited fewer basophils into the inflamed tissue causing less intense Swelling. To our knowledge, this study is the first to show a negative association between carotenoid-based plumage coloration and the magnitude of the PHA-induced immune response.

  • functional analysis of the Skin Swelling response to phytohaemagglutinin
    Functional Ecology, 2010
    Co-Authors: Tomáš Albrecht, Michal Vinkler, Hana Bainová
    Abstract:

    Summary 1. The phytohaemagglutinin (PHA) Skin-Swelling test is widely used in immunoecology and ecotoxicology to estimate cell-mediated immunity. Although often presumed, the involvement of T cells in generating an immune response to PHA in vivo remains unclear. 2. To investigate the mechanism triggering this response we have compared in zebra finch (Taeniopygia guttata) the immune responses to two PHA isolectins differing in their biological properties and one control protein. 3. In Experiment I, we applied PHA-P (the commonly used L and E isolectin mixture) into one wing-web and bovine serum allbumin (BSA) into the other. The Swelling response to PHA-P was significantly stronger than to BSA confirming that the reaction is governed by PHA-specific properties. 4. In Experiment II, purified PHA-L (the T-cell-stimulating isolectin) and PHA-E (the erythroagglutinating isolectin) were compared. Contrary to our expectations, PHA-E induced a significantly stronger Swelling response than PHA-L. Histological analysis revealed significantly higher quantities of erythrocytes and thrombocytes in PHA-E-treated patagia. Nevertheless, there was a positive correlation between the magnitudes of these Swellings. 5. In Experiment III, we tested whether the results obtained by the application of PHA-P and pure PHA-L differ. Here, we failed to find any significant difference between these two preparations in their immunostimulatory activity. Magnitudes of the PHA-L- and PHA-P-induced Swellings were positively correlated. 6. To the best of our knowledge this is the first study to compare the biological activity of purified PHA fractions in vivo and also the first to show the importance of erythroagglutination in the development of an inflammatory response to PHA-P. 7. Our results indicate that the Skin-Swelling test using PHA-P reliably mirrors the individual general proinflammatory potential. However, the immunological background of the test is highly complex and the test results cannot be interpreted as measurements of the adaptive immunity or T-cell activity. This interpretational change importantly alters our view on the test results regarding the costs of the response or the evolutionary immunological adaptations.

  • Functional analysis of the Skin‐Swelling response to phytohaemagglutinin
    Functional Ecology, 2010
    Co-Authors: Michal Vinkler, Hana Bainová, Tomáš Albrecht
    Abstract:

    Summary 1. The phytohaemagglutinin (PHA) Skin-Swelling test is widely used in immunoecology and ecotoxicology to estimate cell-mediated immunity. Although often presumed, the involvement of T cells in generating an immune response to PHA in vivo remains unclear. 2. To investigate the mechanism triggering this response we have compared in zebra finch (Taeniopygia guttata) the immune responses to two PHA isolectins differing in their biological properties and one control protein. 3. In Experiment I, we applied PHA-P (the commonly used L and E isolectin mixture) into one wing-web and bovine serum allbumin (BSA) into the other. The Swelling response to PHA-P was significantly stronger than to BSA confirming that the reaction is governed by PHA-specific properties. 4. In Experiment II, purified PHA-L (the T-cell-stimulating isolectin) and PHA-E (the erythroagglutinating isolectin) were compared. Contrary to our expectations, PHA-E induced a significantly stronger Swelling response than PHA-L. Histological analysis revealed significantly higher quantities of erythrocytes and thrombocytes in PHA-E-treated patagia. Nevertheless, there was a positive correlation between the magnitudes of these Swellings. 5. In Experiment III, we tested whether the results obtained by the application of PHA-P and pure PHA-L differ. Here, we failed to find any significant difference between these two preparations in their immunostimulatory activity. Magnitudes of the PHA-L- and PHA-P-induced Swellings were positively correlated. 6. To the best of our knowledge this is the first study to compare the biological activity of purified PHA fractions in vivo and also the first to show the importance of erythroagglutination in the development of an inflammatory response to PHA-P. 7. Our results indicate that the Skin-Swelling test using PHA-P reliably mirrors the individual general proinflammatory potential. However, the immunological background of the test is highly complex and the test results cannot be interpreted as measurements of the adaptive immunity or T-cell activity. This interpretational change importantly alters our view on the test results regarding the costs of the response or the evolutionary immunological adaptations.

Michal Vinkler - One of the best experts on this subject based on the ideXlab platform.

  • Application of Concanavalin A during immune responsiveness Skin-Swelling tests facilitates measurement interpretation in mammalian ecology.
    Ecology and evolution, 2016
    Co-Authors: Barbora Bílková, Tomáš Albrecht, Milada Chudíčková, Vladimír Holáň, Jaroslav Piálek, Michal Vinkler
    Abstract:

    The Skin-Swelling test is a simple and widespread method used in field ecological research to estimate cellular immune responsiveness in animals. This immunoecological test is based on measuring the magnitude of tissue Swelling response at specific times following subcutaneous application of an experimental pro-inflammatory stimulant. In the vast majority of studies across vertebrate taxa, phytohemagglutinin (PHA) is used as a universal stimulant. Given the complexity of immune response activation pathways of PHA, however, interpretation of test results can be ambiguous. Goal of this study was to improve methodology of the Skin-Swelling test to decrease this ambiguity. Here, we present an alternative protocol aimed at facilitating interpretation of Skin-Swelling data for mammals. Based on previous evidence suggesting that mammalian T cells are readily activated by Concanavalin A (ConA) in vitro, we compared cellular immune responses in vivo to PHA and ConA as an alternative pro-inflammatory stimulant in mice. We measured magnitude of tissue Swelling and compared it with intensity of blood cell infiltration into tissue over a 72-hour interval. Our results corroborate that PHA and ConA show important differences in both dynamics and response amplitude in rodents. ConA induces stronger Swelling with a distinct leukocyte activity pattern and higher pro-inflammatory cytokine (interleukin 6 [IL-6] and interferon gamma[IFN-γ]) expression than PHA during peak response (24-h post-treatment). Furthermore, unlike PHA, magnitude of Swelling was positively associated with cellular activity (number of neutrophils infiltrating tissue) following ConA injection. We conclude that ConA is the more suitable stimulant for Skin-Swelling tests in mammals. This is because of the molecular binding specificity in the two lectins, that is, ConA specifically activates T cells while PHA also triggers erythroagglutination. We propose that ConA be used in all future ecological testing in mammals as it exhibits better performance and its application facilitates immunological interpretation of Skin-Swelling test results.

  • The relationship between health and cell-mediated immunity measured in ecology: Phytohaemagglutinin Skin-Swelling test mirrors blood cellular composition.
    Journal of experimental zoology. Part A Ecological genetics and physiology, 2015
    Co-Authors: Barbora Bílková, Jitka Vinklerová, Michal Vinkler
    Abstract:

    The phytohaemagglutinin (PHA) Skin-Swelling test, a common ecological method for measuring immune responsiveness, uses a subcutaneous injection of PHA to induce an inflammatory response with metrically measurable Swelling. Both the immunological basis of this response and the role of pre-exposure physiology remain poorly understood, however, preventing predictions of costs and benefits of immunity investments revealed by the test and their relationship to life-history traits. In this study, we measure PHA-triggered tissue Swelling, cellular infiltration into inflamed tissue, and haematological changes in zebra finches Taeniopygia guttata, with the aim of identifying those cell types involved in activation of PHA-induced Skin Swelling. We show that the inflammation underlying the Swelling response is dependent on initial haematological state and alters the composition of circulating leukocytes. Injection of PHA decreased heterophil and monocyte frequency and increased basophil frequency, suggesting changes in leukocyte trafficking and haematopoiesis. Higher initial basophil and lymphocyte frequencies in peripheral blood were associated with increased Swelling. High pre-treatment blood lymphocyte levels led to intense lymphocyte migration into inflamed tissue, while high initial basophil levels resulted in lower cellular infiltration. Our results show two possible directions in the association between pre-exposure health and Swelling response: (i) a lymphocyte-based pathway that leads to higher responsiveness in high-quality healthy individuals capable of higher energy and resource investment, or (ii) higher responsiveness in diseased individuals with initially elevated basophil levels and pre-activated immunity. Haematological investigation, therefore, facilitates interpretation of PHA Skin-Swelling test results in ecological immunology, explaining ca. 20 % of variation in Skin-Swelling data. J. Exp. Zool. 323A: 767-777, 2015. © 2015 Wiley Periodicals, Inc.

  • Cytokine expression in phytohaemagglutinin-induced Skin inflammation in a galliform bird
    Journal of Avian Biology, 2013
    Co-Authors: Michal Vinkler, Hana Bainová, Jana Svobodová, Barbora Gabrielová, Anna Bryjová
    Abstract:

    Researchers interested in ecological immunology face substantial methodological problems: 1) most immunological approaches are difficult to perform in free-living animals, 2) in some of the applicable methods the immunological background of the test remains unclear. The latter is also true for the phytohaemagglutinin (PHA) Skin-Swelling test, a trait of cell-mediated immunity commonly measured in ecology. A lack of direct evidence documenting the immunological processes in the tissue limits our understanding of the mechanism triggering the response to PHA. Understanding of this mechanism is, nonetheless, crucial for us to uncover the nature of ecological costs and benefits of investments into the response. As knowledge of cytokine signalling in the tissue may clarify the response mechanism, in our study we investigated the association between the PHA-induced Skin-Swelling and tissue cytokine expression in males of grey partridge Perdix perdix. In PHA-challenged birds we assessed expression of nine cytokines (IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, IL-17, TGF-β, IFN-γ) in wing-web Skin during an early stage of the immune response. We examined the relationship between the magnitude of tissue Swelling and cytokine expression. Contrary to some earlier expectations we did not find any differential expression of T-cell growth factor, IL-2, in the tissue. Hence, T-cell proliferation at the time of the Swelling measurement is unlikely. We detected differential expression in Th17 pro-inflammatory (IL-1β, IL-6) and anti-inflammatory (TGF-β) cytokines. The PHA-induced Swelling response was only weakly linked to the expression of TGF-β. We also found relationships between the PHA-induced Swelling response and phenotypic traits of the birds; the PHA Swelling was positively associated with the extent of melanin-based breast ornamentation and negatively related to body size. Our results might suggest that variation in Swelling is influenced by total numbers of responding cells rather than by differences in signalling. Moreover, we revealed significant correlations in expression of IL-1β, IL-6 and TGF-β. These findings are the first to show on the molecular level that the PHA Skin-Swelling test actually measures inflammation process which is part of innate immune defence and not the adaptive immune response (as assumed if the test was the reflection of T-cell proliferation).

  • Phytohaemagglutinin Skin-Swelling test in scarlet rosefinch males: low-quality birds respond more strongly
    Animal Behaviour, 2012
    Co-Authors: Michal Vinkler, Jan Schnitzer, Pavel Munclinger, Tomáš Albrecht
    Abstract:

    The phytohaemagglutinin (PHA) Skin-Swelling test is one of the most widely used methods for cell-mediated immunity measurement in immunoecology. Although several studies have investigated the condition-dependent traits associated with the magnitude of cutaneous inflammatory response to PHA, the results concerning signalling of the responsiveness through ornamental traits are still controversial. This is especially true for carotenoid-based feather ornamentation in birds. We therefore examined the linkage between several condition-dependent traits, including the red ornamental coloration of the plumage, and the magnitude of the PHA-induced immune response in scarlet rosefinch, Carpodacus erythrinus, males. Our results show two important aspects of the PHA-induced inflammation in this species. First, histological analysis showed that the Swelling response was dependent on basophil activity. Second, the magnitude of the response (increase in patagium thickness) was associated with individual size, carotenoid-based ornamental coloration and a ptilochronological marker of feather growth at the time of moulting (mean growth bar width), thus mirroring the long-term quality of the individual. The positive linkage between the individual size or mean growth bar width and the PHA response suggests an association between the magnitude of the response and individual metabolic rate. However, as the magnitude of the response was also related negatively to ornament saturation and positively to ornament lightness, our results indicate stronger responsiveness in inferior males. Highly ornamented, healthier individuals recruited fewer basophils into the inflamed tissue causing less intense Swelling. To our knowledge, this study is the first to show a negative association between carotenoid-based plumage coloration and the magnitude of the PHA-induced immune response.

  • functional analysis of the Skin Swelling response to phytohaemagglutinin
    Functional Ecology, 2010
    Co-Authors: Tomáš Albrecht, Michal Vinkler, Hana Bainová
    Abstract:

    Summary 1. The phytohaemagglutinin (PHA) Skin-Swelling test is widely used in immunoecology and ecotoxicology to estimate cell-mediated immunity. Although often presumed, the involvement of T cells in generating an immune response to PHA in vivo remains unclear. 2. To investigate the mechanism triggering this response we have compared in zebra finch (Taeniopygia guttata) the immune responses to two PHA isolectins differing in their biological properties and one control protein. 3. In Experiment I, we applied PHA-P (the commonly used L and E isolectin mixture) into one wing-web and bovine serum allbumin (BSA) into the other. The Swelling response to PHA-P was significantly stronger than to BSA confirming that the reaction is governed by PHA-specific properties. 4. In Experiment II, purified PHA-L (the T-cell-stimulating isolectin) and PHA-E (the erythroagglutinating isolectin) were compared. Contrary to our expectations, PHA-E induced a significantly stronger Swelling response than PHA-L. Histological analysis revealed significantly higher quantities of erythrocytes and thrombocytes in PHA-E-treated patagia. Nevertheless, there was a positive correlation between the magnitudes of these Swellings. 5. In Experiment III, we tested whether the results obtained by the application of PHA-P and pure PHA-L differ. Here, we failed to find any significant difference between these two preparations in their immunostimulatory activity. Magnitudes of the PHA-L- and PHA-P-induced Swellings were positively correlated. 6. To the best of our knowledge this is the first study to compare the biological activity of purified PHA fractions in vivo and also the first to show the importance of erythroagglutination in the development of an inflammatory response to PHA-P. 7. Our results indicate that the Skin-Swelling test using PHA-P reliably mirrors the individual general proinflammatory potential. However, the immunological background of the test is highly complex and the test results cannot be interpreted as measurements of the adaptive immunity or T-cell activity. This interpretational change importantly alters our view on the test results regarding the costs of the response or the evolutionary immunological adaptations.

Michael Heistermann - One of the best experts on this subject based on the ideXlab platform.

  • female sexual behavior but not sex Skin Swelling reliably indicates the timing of the fertile phase in wild long tailed macaques macaca fascicularis
    Hormones and Behavior, 2005
    Co-Authors: Antje Engelhardt, Keith J Hodges, Carsten Niemitz, Michael Heistermann
    Abstract:

    The extent to which catharrine primate males are able to discern the fertile phase during the female ovarian cycle under natural conditions is still debated. In a recent study, we showed that wild male long-tailed macaques are able to detect the fertile phase, but the cues males used to assess female reproductive status remained unclear. In the present study, we tested female sex Skin Swelling and specific female behaviors for their reliability in signaling the fertile phase, as determined by measurement of fecal estrogens (E) and progestogens (P) during nine ovulatory cycles in seven free-ranging females. We found that changes in sex Skin Swellings showed a significant positive correlation to the E/P ratio, but Swelling size did not significantly differ between cycle phases. In contrast, the frequency of two of the tested female behaviors, namely initiation of sexual interactions and reaching back for the male during copulation, was not only correlated with female reproductive hormones, but was significantly elevated during the fertile phase compared to nonfertile phases of the cycle. We thus conclude that female sex Skin Swelling does not reliably indicate the timing of the fertile phase in long-tailed macaques, whereas certain female behaviors do. Since cycles differed considerably in the number of males with which females had sexual interactions as well as in the number of sexual interactions with dominant males, the signaling character of these specific female behaviors appears to be robust against inconsistencies in these social variables. Female behavior might therefore play an important role in the recognition of the fertile phase by male macaques under natural conditions.

  • Timing and probability of ovulation in relation to sex Skin Swelling in wild West African chimpanzees, Pan troglodytes verus
    Animal Behaviour, 2003
    Co-Authors: Tobias Deschner, Michael Heistermann, J. Keith Hodges, Christophe Boesch
    Abstract:

    Females of many catharrine primates show a periodic and often pronounced Swelling of the perineum, the functional significance of which is unclear. Several hypotheses that exist to explain the function of this conspicuous trait are based on assumptions about the temporal relation between the period of maximum Swelling and ovulation, and remain largely untested. We examined this relation in free-living chimpanzees of the Tao ¨ National Park, Cote d'Ivoire, and assessed the reliability of perineal Swelling as an indicator of ovulation in this species. We used noninvasive urinary progestogen analysis of female reproductive status, together with observational data on Swelling characteristics, to determine the variability of timing of ovulation within the maximum Swelling phase in 36 cycles from 12 females. The period of maximum Swelling was highly variable, lasting from 6 to 18 days. Although ovulation was virtually restricted to the second half of the period of maximum tumescence, its timing varied considerably in relation to both the onset and the end of the maximum tumescence phase. Probability of ovulation, however, was not random, but peaked on day 7 after the onset of the maximum Swelling phase, and was almost 60% between days 7 and 9. Thus, in wild chimpanzees perineal Swelling indicates the probability of ovulation, but does not provide sufficient information to deduce its exact timing. Given the temporal variability of ovulation relative to the last day of maximum tumescence, field workers should try to include hormonal analysis if information on timing of ovulation is required for interpretation of observational data.  2003 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour.

Richard Shine - One of the best experts on this subject based on the ideXlab platform.

  • measuring amphibian immunocompetence validation of the phytohemagglutinin Skin Swelling assay in the cane toad rhinella marina
    Methods in Ecology and Evolution, 2011
    Co-Authors: Gregory P Brown, Catherine M Shilton, Richard Shine
    Abstract:

    Summary 1. Measuring the degree of Skin-Swelling induced by intradermal injection of phytohemagglutinin (PHA) is simple, quick and inexpensive, does not require specialized equipment and is easily conducted under field conditions. 2. PHA is perhaps the most frequently used assay of immunocompetence in field studies of birds. However, the method has rarely been used, and never validated, for studies on ectothermic vertebrates. 3. Here, we document its use in an amphibian. In response to PHA injected into a toe web, cane toads exhibited a 35% increase in web thickness 24 h postinjection. 4. Histologically, PHA injection initiated a rapid (<12 h) infiltration of neutrophils, eosinophils and macrophages at the injection site, followed by an influx of lymphocytes by 24 h postinjection. A second exposure to PHA stimulated a faster, more intense Swelling response. 5. In cane toads, PHA injection elicits a rapid innate immune response, followed by a secondary response that may reflect cell-mediated immune activity. Both components are easily quantifiable by the degree of Skin-Swelling. 6. Hence, PHA injection offers a convenient assay to quantify immune function in anurans and could usefully be incorporated into studies on the reasons for global amphibian declines.

  • Measuring amphibian immunocompetence: validation of the phytohemagglutinin Skin-Swelling assay in the cane toad, Rhinella marina
    Methods in Ecology and Evolution, 2011
    Co-Authors: Gregory P Brown, Catherine M Shilton, Richard Shine
    Abstract:

    Summary 1. Measuring the degree of Skin-Swelling induced by intradermal injection of phytohemagglutinin (PHA) is simple, quick and inexpensive, does not require specialized equipment and is easily conducted under field conditions. 2. PHA is perhaps the most frequently used assay of immunocompetence in field studies of birds. However, the method has rarely been used, and never validated, for studies on ectothermic vertebrates. 3. Here, we document its use in an amphibian. In response to PHA injected into a toe web, cane toads exhibited a 35% increase in web thickness 24 h postinjection. 4. Histologically, PHA injection initiated a rapid (

Gregory P Brown - One of the best experts on this subject based on the ideXlab platform.

  • measuring amphibian immunocompetence validation of the phytohemagglutinin Skin Swelling assay in the cane toad rhinella marina
    Methods in Ecology and Evolution, 2011
    Co-Authors: Gregory P Brown, Catherine M Shilton, Richard Shine
    Abstract:

    Summary 1. Measuring the degree of Skin-Swelling induced by intradermal injection of phytohemagglutinin (PHA) is simple, quick and inexpensive, does not require specialized equipment and is easily conducted under field conditions. 2. PHA is perhaps the most frequently used assay of immunocompetence in field studies of birds. However, the method has rarely been used, and never validated, for studies on ectothermic vertebrates. 3. Here, we document its use in an amphibian. In response to PHA injected into a toe web, cane toads exhibited a 35% increase in web thickness 24 h postinjection. 4. Histologically, PHA injection initiated a rapid (<12 h) infiltration of neutrophils, eosinophils and macrophages at the injection site, followed by an influx of lymphocytes by 24 h postinjection. A second exposure to PHA stimulated a faster, more intense Swelling response. 5. In cane toads, PHA injection elicits a rapid innate immune response, followed by a secondary response that may reflect cell-mediated immune activity. Both components are easily quantifiable by the degree of Skin-Swelling. 6. Hence, PHA injection offers a convenient assay to quantify immune function in anurans and could usefully be incorporated into studies on the reasons for global amphibian declines.

  • Measuring amphibian immunocompetence: validation of the phytohemagglutinin Skin-Swelling assay in the cane toad, Rhinella marina
    Methods in Ecology and Evolution, 2011
    Co-Authors: Gregory P Brown, Catherine M Shilton, Richard Shine
    Abstract:

    Summary 1. Measuring the degree of Skin-Swelling induced by intradermal injection of phytohemagglutinin (PHA) is simple, quick and inexpensive, does not require specialized equipment and is easily conducted under field conditions. 2. PHA is perhaps the most frequently used assay of immunocompetence in field studies of birds. However, the method has rarely been used, and never validated, for studies on ectothermic vertebrates. 3. Here, we document its use in an amphibian. In response to PHA injected into a toe web, cane toads exhibited a 35% increase in web thickness 24 h postinjection. 4. Histologically, PHA injection initiated a rapid (