Expression Of CXCLi2 Research Articles

Acquisition of immunity to the protozoan parasite Eimeria adenoeides in turkey poults and cellular responses to infection

Newly hatched turkey poults were infected with 102 oocysts of Eimeria adenoeides and subsequently reinfected with 103 and 104 oocysts at 6 and 12 d of age, respectively. Three peaks in oocyst production were observed in the feces of poults following this series of infections. A second group of poults given the same dosing regimen was challenged with 5 × 104 oocysts/poult at different times to evaluate the acquisition of immunity. Judging by weight gain and mortality, no protection had been acquired at 6 d of age, but partial protection was observed by 12 and 18 d of age. A third group of poults were also infected with 102 oocysts and subsequently reinfected with 103 and 104 oocysts at 6 and 12 d of age to evaluate cellular immune responses to infection. Sections of ceca from infected poults showed a significantly higher leukocyte infiltration on d 6, 10, 12, 16, and 18 after infection than uninfected controls. The percent area occupied by CD4+ and CD8+ lymphocytes in the ceca, as assessed by immunohistochemistry, was significantly elevated in infected poults on d 12, 16, and 18. The relative expression of chemokine CXCLi2, and cytokines IL1β, IFNγ, IL10, IL13, IL2, IL12b, and IL18 was measured by real-time reverse-transcription PCR. The expression of CXCLi2 and IL10 was found to be elevated on d 12, and IFNγ on d 10, 12, and 16. Expression of IL13 and IL18 was increased on d 10 and IL2 on d 10 and 16, and that of IL12b on d 16 in infected poults. Increase in the infiltration of leukocytes, percent area occupied by CD4+ and CD8+ lymphocytes, and changes in the relative expression of cytokines in the ceca characterize the dynamics of immune responses in turkey poults infected with E. adenoeides early in life.

Effects of lipopolysaccharide on the expression of proinflammatory cytokines and chemokines and the subsequent recruitment of immunocompetent cells in the oviduct of laying and molting hens

The goal of this study was to examine whether lipopolysaccharide (LPS) induces the expression of proinflammatory cytokines and chemokines and recruits T cells in the lower part of the oviduct, and whether that response to LPS is different between the laying and molting phase. White Leghorn laying and molting hens were intravenously injected with saline (control) or LPS. The uterus and vagina of oviducts were collected 3 or 6 h after injection, and used for reverse transcription PCR analysis of IL-1β, IL-6, IL-8 (CXCLi2), and lymphotactin (Lptn), and for immunohistochemical analysis for the frequency of CD4+ and CD8+ T cells. The expressions of IL-1β, IL-6, and CXCLi2 in the uterus and that of IL-1β in the vagina were upregulated in response to LPS 3 or 6 h after injection in both laying and molting hens. The CXCLi2 expression in the vagina was upregulated by LPS in laying hens, whereas those effects of LPS were not significant in molting hens. Expression of Lptn showed a tendency to be downregulated after 3 h, with recovery by 6 h after LPS injection. The frequency of CD4+ T cells tended to increase in response to LPS after 6 h in the lamina propria of the uterus and vagina in both laying and molting hens. The CD8+ T cell frequencies in the lamina propria of the uterus and vagina of laying hens increased in response to LPS after 6 h. However, in the molting hens, LPS stimulation resulted in CD8+ T cell increase in the vagina only and not in the uterus. These results suggest that expressions of proinflammatory cytokines and CXCLi2 chemokine are upregulated in association with T cell recruitment in response to LPS in the lower part of the oviduct, although CD8+ T cells in the uterus may be depressed during the molting phase. These immunoresponses may play roles in the defense against infection of the oviduct.

Proportion of circulating chicken heterophils and CXCLi2 expression in response to Salmonella enteritidis are affected by genetic line and immune modulating diet

Genetic line and diet affect chicken heterophil activity and gene expression, and the combination of these factors can enhance disease resistance. This study evaluated the effects of immune modulating diets on heterophil/lymphocyte (H/L) ratio and heterophil chemokine expression in distinct genetic lines. Fayoumi and Leghorn chickens were fed a basal diet or immune modulating diets enhanced with β-glucans, ascorbic acid, or corticosterone. H/L ratios and heterophil gene expression in response to in vitro stimulation with Salmonella enteritidis (SE) were evaluated on days 1, 3, 7, and 21 of diet treatment. The stress-mimicking corticosterone diet influenced H/L ratio in the Leghorn line, but not the Fayoumi line, suggesting resistance to stress-induced immunosuppression in the Fayoumi line. Leghorn line H/L ratios were increased on days 1 and 3 of corticosterone diet treatment, but not days 7 or 21. Expression of CXCLi2 by SE stimulated heterophils was higher in the Leghorn line, suggesting that Leghorns rely more heavily on inflammatory response than do Fayoumis. Corticosterone diet was associated with reduced CXCLi2 expression in heterophils from both lines. Dietary β-glucan or ascorbic acid did not affect H/L ratio or CXCLi2 expression, suggesting that benefits of these immunomodulators may not be evident in healthy birds.

Characterization of the Immunological Response to Dermanyssus gallinae Infestation in Domestic Fowl

Dermanyssus gallinae is a haematophagous ectoparasite of birds, which adversely affects both production and welfare of commercial poultry. Poultry in commercial production systems chronically exposed to D. gallinae do not appear to develop immunity to the mite. The objective of the current study was to determine the initial immune response of domestic fowl following exposure to D. gallinae. Two groups of birds (11 birds/group) had mite chambers secured to their backs. Controls received no mites, while infested birds received 200 unfed female D. gallinae on day 0 which were then removed on day 1 or 2. Spleen samples were collected on days -1, 1, 2 and 5. The expression of Th1 (IFNgamma, CXCLi2, IL6 and IL18), Th2 (IL4, IL10 and IL13) cytokines/chemokines normalized against a reference gene, GAPDH, were determined by semi-quantitative RT-PCR. Although there were no significant differences between treatments, numerical trends were observed. Th2 cytokine expression was not detected in any birds on any day. IL6, CXCLi2, IFNgamma and IL18 expression was increased on day 1 in the infested group, while on day 2 CXCLi2 and IFNgamma were lower and IL6 and IL18 levels were similar between treatments. The IL18 expression was similar between treatments on day 5, while IL6 and IFNgamma levels were increased and CXCLi2 expression was decreased in the infested group. Data suggest that D. gallinae feeding stimulates Th1 and pro-inflammatory cytokines/chemokines initially (day 1) followed by their subsequent down regulation. This study is the first report of the characterization of the immunological response of the domestic fowl to controlled numbers of D. gallinae.