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PubMedDate not supplied

Natural killer cell activity in chickens exposed to Marek's disease virus: inhibition of activity in susceptible chickens and enhancement of activity in resistant and vaccinated chickens.

Chickens of 2 genetic lines (lines P and N) were inoculated with a pathogenic strain of Marek's disease (MD) virus (MDV) and chronologically examined for disease response and natural killer (NK) cell expression. The NK cell reactivity was assayed in an in vitro cytotoxicity assay in which effector cells from the spleen of test chickens were reacted with 51Cr-labeled LSCC-RP9 target cells. Chickens of line P developed progressive debilitating disease and a high incidence of gross tumors and death. The NK cell reactivity of line-P chickens infected with MDV was significantly lower than that of uninfected control hatchmates. In contrast, NK cell levels were significantly elevated in MDV-inoculated line-N chickens that were resistant to MD and in chickens of lines P or N that had been inoculated with herpesvirus of turkeys (HVT). NK cell levels were also elevated in line P if chickens were vaccinated with HVT before infection with MDV. Inhibition of NK reactivity in susceptible chickens and elevation of reactivity in naturally resistant or vaccinated chickens may indicate a role for the NK cell system in regulating resistance to MD.

Animals↗
PubMed2006

Effects of chicken intestinal antimicrobial peptides on humoral immunity of chickens and antibody titres after vaccination with infectious bursal disease virus vaccine in chicken.

Sixty chickens were randomly divided into two groups (30 chickens in each group) to determine the effect of oral administration of chicken intestinal antimicrobial peptides (CIAMP) on the humoral immune response. Chickens of both groups were fed the same diet. In the treatment group chickens received drinking water supplemented with CIAMP (1 microg/ml) right after hatching. Samples of blood, bursa of Fabricus, spleen and intestine were taken at day 1, 4, 7, 10 and 17 of experiment. CIAMP supplementation enhanced the content of IgG and IgM in serum from day 4-10 and day 10-17, respectively, (p < 0.05), IgM-forming cells in bursa of Fabricus and spleen at the age of 7 days (p < 0.05) and IgG-forming cells in bursa of Fabricus at the age of 4 days (p < 0.05). In addition, CIAMP enhanced the IgA-forming cells in caecal tonsils diffuse area at day 4 (p < 0.05). Furthermore, CIAMP enhanced the antibody response to infectious bursal disease virus vaccine (IBDV) in chickens 21 days following IBDV vaccine administration (p < 0.05). These results suggested that CIAMP could modulate the humoral immune response of chickens and increased the antibody titres of infectious bursal disease virus vaccine.

Animals↗
PubMed1980

Double-immunofluorescent staining of isolated smooth muscle cells. I. preparation of anti-chicken gizzard alpha-actinin and its use with anti-chicken gizzard myosin for co-localization of alpha-actinin and myosin in chicken gizzard cells.

Contractile proteins have been co-localized by double-immunofluorescent staining in several types of cultured cells. Since freshly isolated smooth muscle cells are more representative of the organization within smooth muscle cells in the intact tissue than cultured cells, the present study was undertaken to determine the feasibility of using double-staining techniques in freshly isolated cells. A new method of purifying alpha-actinin from chicken gizzards was used to provide antigen for raising anti-alpha-actinin. Fluorescein isothiocyanate-labelled anti-alpha-actinin (FAalphaA) was used in conjunction with tetramethyl rhodamine isothiocyanate-labelled anti-myosin (TRAM) Ouchterlongy gels against myosin, tropomyosin, actin, and alpha-actinin showed that antimyosin reacted only with myosin, anti-alpha-actinin only with alpha-actinin. Anti-alpha-actinin stained only the Z-line of isolated chicken skeletal muscle myofibrils. FAalphaA stained bright, discrete patches or strips on the plasma membrane, while TRAM was excluded from these areas. FAalphaA stained myofibrils faintly in a striated pattern, while TRAM stained myofibrils heavily with less evident striations. Evidence for extramyofibrillar localization of alpha-actinin within the cytoplasm was inconclusive. Although antibodies were quite specific in their labelling, resolution with double-staining was subject to the same limitations described for single labelling of whole cells (Bagby and Pepe 1978). Double-staining of whole cells is just as feasible as single-staining. Indeed, having a definite marker for myofibrils (TRAM) makes the localization of alpha-actinin much easier to interpret.

Actinin↗
PubMed1994

The far upstream chicken lysozyme enhancer at -6.1 kilobase, by interacting with NF-M, mediates lipopolysaccharide-induced expression of the chicken lysozyme gene in chicken myelomonocytic cells.

Macrophages respond to lipopolysaccharide (LPS) with the activation of various genes, including the lysozyme gene. Here, we show that the level of lysozyme mRNA increases following treatment of chicken myelomonocytic HD11 cells with LPS. By transient and stable transfection of the chloramphenicol acetyltransferase (CAT) gene controlled by regulatory elements of the lysozyme gene, we identified a subfragment of the -6.1 kilobase (kb) lysozyme enhancer that mediates the LPS-induced lysozyme expression. This subfragment contains two elements (D and E), each of which matches the highly degenerate consensus sequence of binding sites for C/EBP-like transcription factors. Furthermore, we found protein complexes to interact with elements D and E whose binding activity to elements D and E is LPS-inducible in myelomonocytic HD11 cells. Immunomobility shift assays show that NF-M, a myeloid-specific C/EBP beta-related transcription factor is an essential component of these protein complexes. Mutations of the C/EBP binding sites within D and E cause a reduction of basal activity and abolish LPS responsiveness of the -6.1 kb lysozyme enhancer. These results show that the -6.1 kb lysozyme enhancer, in addition to its role in cell type-specific expression, can mediate, by interacting with NF-M, LPS-induced expression of the lysozyme gene in chicken myelomonocytic cells.

Animals↗
PubMed1989

Selective autoimmune response to the chicken-specific structures of thyroglobulin in Obese strain chickens.

The characteristics of thyroglobulin (Tg) autoantibodies in Obese strain (OS) chickens with thyroiditis have been defined and compared with those of polyclonal antibodies to chicken Tg produced by immunizing normal chickens and a rabbit, and with mouse monoclonal antibodies (MoAb) to chicken Tg. Chicken Tg autoantibodies (aAb), when tested against Tg from 24 species all showed specificity for chicken Tg which ranged from absolute to limited although in most instances cross-reactions with Tgs of other species were either absent or at a low level. Antibodies to chicken Tg produced by immunization showed a similar limited range of cross-reactions. Four of five chTg-MoAbs were specific for chicken Tg and the fifth was almost so. In competitive experiments, the polyclonal rabbit antibody could fully inhibit binding of all chicken Tg-aAb to chicken Tg but not vice versa. It was inferred that polyclonal rabbit Tg antiserum includes antibodies to all the epitopes seen by chicken Tg-aAb and many more besides. In similar experiments with four chicken Tg-MoAbs, the binding of one chicken Tg-aAb was unaffected, and three other patterns of inhibitions were defined. The binding to chicken Tg of a fifth chicken Tg-MoAb was enhanced rather than inhibited by chicken Tg-aAb. Some but not all chicken Tg-aAb preparations could differentiate between Tgs containing different amounts of thyroxine. We conclude that the autoantibodies to Tg in OS chickens are directed in the main against determinants unique to the species. Not all the species-specific determinants are involved in the autoimmune response but the number of epitopes involved is at least four. In these respects the immune response to Tg in OS chickens resembles that in autoimmune thyroid disease in humans. The conformation of chicken Tg may be affected by combination with antibody or by the content of thyroid hormone.

Animals↗
PubMed2004

Genetic identification of avian hepatitis E virus (HEV) from healthy chicken flocks and characterization of the capsid gene of 14 avian HEV isolates from chickens with hepatitis-splenomegaly syndrome in different geographical regions of the United States.

Avian hepatitis E virus (HEV), a novel virus identified from chickens with hepatitis-splenomegaly (HS) syndrome, is genetically and antigenically related to human HEV. Recently, it was found that avian HEV antibody is also prevalent in healthy chickens. A prospective study was done on a known seropositive but healthy chicken farm to identify avian HEV isolates from healthy chickens. Fourteen chickens were randomly selected, tagged and monitored under natural conditions for 19 weeks. All 14 chickens were seronegative at the beginning of the study at 12 weeks of age. By 21 weeks of age, all 14 chickens had seroconverted to avian HEV antibody. None of the chickens had any sign of HS syndrome. Partial helicase gene and capsid gene sequences of avian HEV isolates recovered from a healthy chicken were determined and found to share 75-97 % nucleotide sequence identity with the corresponding regions of avian HEV isolates from chickens with HS syndrome. Thus far, only one strain of avian HEV from a chicken with HS syndrome has been genetically characterized for its capsid gene, therefore the capsid gene region of an additional 14 isolates from chickens with HS syndrome were also characterized. The capsid genes of avian HEV isolates from chickens with HS syndrome were found to be heterogeneic, sharing 76-100 % nucleotide sequence identity with each other. This study indicates that avian HEV is enzootic in chicken flocks and spreads subclinically among chickens in the United States and that the virus is heterogeneic.

Aging↗
PubMed1985

Interaction of oxidized chicken ovotransferrin with chicken embryo red blood cells.

Iron-saturated chicken ovotransferrin was chemically oxidized with NaIO4, converting 50% of its methionine residues to their sulfoxide derivatives while maintaining 95% of its iron-binding activity. The oxidized chicken ovotransferrin was able to deliver iron to the chicken embryo red blood cell for heme synthesis. From competition experiments, oxidized diferric chicken ovotransferrin was estimated to be approx. 65% as efficient as unmodified diferric chicken ovotransferrin at competing with diferric (55Fe2) chicken ovotransferrin for the iron-donating sites of the chicken embryo red blood cells. The presence of apo chicken ovotransferrin preparations (native or oxidized) in the incubation medium had little effect on the rate of iron incorporation into heme from diferric chicken ovotransferrin. The effect of modifying the periodate-susceptible methionine residues in chicken ovotransferrin was small but significant. These methionine residues do not appear critical for the interaction of chicken ovotransferrin with the chicken embryo red blood cell receptors, the incorporation of chicken ovotransferrin into the cell, or the release of iron from chicken ovotransferrin for heme synthesis.

Animals↗
PubMed1988

Interaction of endogenous chicken gonadotrophin-releasing hormone-I and -II on chicken pituitary cells.

The presence of two endogenous forms of gonadotrophin-releasing hormone (GnRH) in the chicken hypothalamus (chicken GnRH-I ([Gln8]GnRH) and chicken GnRH-II ([His5, Trp7, Tyr8]GnRH)), and the stimulation of gonadotrophins by both forms, suggests the possible existence of GnRH receptor subtypes and gonadotroph subtypes in the chicken pituitary. This question was investigated by assessing the effects of various combinations of the two known forms of chicken hypothalamic GnRH and antagonist analogues of GnRH on LH release from dispersed chicken anterior pituitary cells in both static and perifused systems. The relative inhibition of chicken GnRH-I-stimulated and chicken GnRH-II-stimulated LH release by 12 GnRH antagonists did not differ significantly, suggesting a single GnRH receptor type. Chicken GnRH-II was approximately sixfold more potent than chicken GnRH-I in releasing LH. Release of LH in response to maximal doses of chicken GnRH-I and chicken GnRH-II and to a mixture of both was similar and the two peptides were not additive in their effects, consistent with the presence of a single type of LH gonadotroph and a GnRH receptor which binds both forms of GnRH. Each form of GnRH desensitized cells to subsequent stimulation with the other form, providing additional evidence for a single type of LH gonadotroph. These findings suggest that chicken GnRH-I and -II stimulate gonadotrophin release through a single GnRH receptor type on a single class of LH gonadotroph in the chicken pituitary.

Animals↗
PubMed2006

Chicken genomics resource: sequencing and annotation of 35,407 ESTs from single and multiple tissue cDNA libraries and CAP3 assembly of a chicken gene index.

Its accessibility, unique evolutionary position, and recently assembled genome sequence have advanced the chicken to the forefront of comparative genomics and developmental biology research as a model organism. Several chicken expressed sequence tag (EST) projects have placed the chicken in 10th place for accrued ESTs among all organisms in GenBank. We have completed the single-pass 5'-end sequencing of 37,557 chicken cDNA clones from several single and multiple tissue cDNA libraries and have entered 35,407 EST sequences into GenBank. Our chicken EST sequences and those found in public databases (on July 1, 2004) provided a total of 517,727 public chicken ESTs and mRNAs. These sequences were used in the CAP3 assembly of a chicken gene index composed of 40,850 contigs and 79,192 unassembled singlets. The CAP3 contigs show a 96.7% match to the chicken genome sequence. The University of Delaware (UD) EST collection (43,928 clones) was assembled into 19,237 nonredundant sequences (13,495 contigs and 5,742 unassembled singlets). The UD collection contains 6,223 unique sequences that are not found in other public EST collections but show a 76% match to the chicken genome sequence. Our chicken contig and singlet sequences were annotated according to the highest BlastX and/or BlastN hits. The UD CAP3 contig assemblies and singlets are searchable by nucleotide sequence or key word (http://cogburn.dbi.udel.edu), and the cDNA clones are readily available for distribution from the chick EST website and clone repository (http://www.chickest.udel.edu). The present paper describes the construction and normalization of single and multiple tissue chicken cDNA libraries, high-throughput EST sequencing from these libraries, the CAP3 assembly of a chicken gene index from all public ESTs, and the identification of several nonredundant chicken gene sets for production of custom DNA microarrays.

Animals↗
PubMed1984

Biological properties of chicken luteinizing hormone-releasing hormone: gonadotropin release from rat and chicken cultured anterior pituitary cells and radioligand analysis.

We have examined the biological properties of chicken LHRH, which has been isolated and characterized in our laboratory, using primary monolayer cultures of rat and chicken anterior pituitary cells. The radioligand receptor analysis using rat pituitary LHRH receptor was also performed. Biological activities of mammalian LHRH and a more potent analog, [D-Leu6]des-Gly10-LHRH N-ethylamide ([D-Leu6] LHRH analog), were compared with those of chicken LHRH. The ED50 values for [D-Leu6]LHRH analog, mammalian LHRH, and chicken LHRH were, respectively, 0.0166, 0.455, and 18.2 nM for LH secretion and 0.0089, 0.263, and 8.28 nM for FSH secretion from rat pituitary cells. Relative potencies of chicken LHRH were 2.5% that of mammalian LHRH for LH and 3.2% that for FSH. On the other hand, the ED50 for chicken LHRH for LH release from chicken anterior pituitary cells was 1.03 nM, indicating that the biological potency of chicken LHRH acting on chicken pituitary cells was higher than that of chicken LHRH acting on mammalian pituitary cells. The ID50 of chicken LHRH to inhibit the binding of 125I-labeled [D-Leu6]LHRH analog to rat anterior pituitary membrane was 708.5 nM, and was 200 times that of mammalian LHRH (3.39 nM). These results suggest that the substitution of arginine residue of mammalian LHRH for glutamine residue of chicken LHRH causes a decrease in the binding affinity of the hormone for the mammalian LHRH receptor and that the mammalian LHRH receptor has a binding site for the cationic center of the arginine residue of LHRH. On the other hand, chicken pituitary LHRH receptor seems to have more broad specificity than mammalian LHRH receptor.

Animals↗
PubMed2024

Intestinal microbiome profiles in broiler chickens raised without antibiotics exhibit altered microbiome dynamics relative to conventionally raised chickens.

The present study was undertaken to profile and compare the cecal microbial communities in conventionally (CONV) grown and raised without antibiotics (RWA) broiler chickens. Three hundred chickens were collected from five CONV and five RWA chicken farms on days 10, 24, and 35 of age. Microbial genomic DNA was extracted from cecal contents, and the V4-V5 hypervariable regions of the 16S rRNA gene were amplified and sequenced. Analysis of 16S rRNA sequence data indicated significant differences in the cecal microbial diversity and composition between CONV and RWA chickens on days 10, 24, and 35 days of age. On days 10 and 24, CONV chickens had higher richness and diversity of the cecal microbiome relative to RWA chickens. However, on day 35, this pattern reversed such that RWA chickens had higher richness and diversity of the cecal microbiome than the CONV groups. On days 10 and 24, the microbiomes of both CONV and RWA chickens were dominated by members of the phylum Firmicutes. On day 35, while Firmicutes remained dominant in the RWA chickens, the microbiome of CONV chickens exhibited am abundance of Bacteroidetes. The cecal microbiome of CONV chickens was enriched with the genus Faecalibacterium, Pseudoflavonifractor, unclassified Clostridium_IV, Bacteroides, Alistipes, and Butyricimonas, whereas the cecal microbiome of RWA chickens was enriched with genus Anaerofilum, Butyricicoccu, Clostridium_XlVb and unclassified Lachnospiraceae. Overall, the cecal microbiome richness, diversity, and composition were greatly influenced by the management program applied in these farms. These findings provide a foundation for further research on tailoring feed formulation or developing a consortium to modify the gut microbiome composition of RWA chickens.

Animals↗
PubMed2004

Chicken leukemia inhibitory factor maintains chicken embryonic stem cells in the undifferentiated state.

Mouse embryonic stem (ES) cells can be maintained in an undifferentiated state in the presence of leukemia inhibitory factor (LIF), a member of the interleukin-6 cytokine family. In other mammals, this is not possible with LIF alone. Chicken ES-like cells (blastodermal cells) have only been cultured with mouse LIF because chicken LIF was not available. However the culture system is imperfect and chicken ES-like cells equivalent to mouse ES cells were not observed. In the present study, we cloned the cDNA-encoding chicken LIF using mRNA subtraction and RACE methodology. The chicken LIF cDNA encodes a protein with approximately 40% sequence identity to mouse LIF. It has 211 amino acids including a putative N-terminal signal peptide of 24 residues. Chicken blastodermal cells were cultured in the presence of bacterially expressed chicken LIF or mouse LIF. The expression of alkaline phosphatase and embryonal carcinoma cell monoclonal antibody-1 and stage-specific embryonic antigen-1 and the activation of STAT3 were examined, all of which are indices of the undifferentiated state. Exposure in the blastodermal cells to recombinant chicken LIF but not to mouse LIF maintained the expression of these various markers. After 9 days of incubation, the blastodermal cells formed cystic embryoid bodies in the presence of mouse LIF but not in the presence of recombinant chicken LIF. We conclude that chicken LIF is able to maintain chicken ES cell cultures in the undifferentiated state.

Alkaline Phosphatase↗
PubMed1986

[The effect of synthetic chicken LH-RH on the release of LH and FSH and ovulation in rats (a comparative study of synthetic mammalian LH-RH and chicken LH-RH)].

Recently, Miyamoto et al and King et al, independently isolated chicken LH-RH and determined its chemical structure as [Gln8] LH-RH. In this report, the in vivo effect of synthetic chicken LH-RH on the release of LH and FSH and ovulation in rats was investigated. A single i.v. injection of chicken LH-RH, as well as mammalian LH-RH, induced a significant increase of plasma LH levels at 15 min after injection in adult male rats. Plasma LH levels then declined at 30 min to 60 min and returned to basal levels at 120 min. The biological potency of chicken LH-RH estimated from plasma LH levels at 15 min after injection in adult male rats by parallel line assay was 4.1% of that of mammalian LH-RH. It was likely that the activity of chicken LH was shorter in duration on the LH secretion as compared with that of mammalian LH-RH because of quickly decreased plasma LH levels. Plasma FSH levels were also increased, but the increment of FSH was not so obvious as compared with that of LH. Plasma FSH levels reached a plateau at 15 min and did not return to basal levels at 120 min in either the chicken LH-RH injection groups or the mammalian LH-RH injection groups. The chicken LH-RH was able to induce an increase of plasma LH and FSH and ovulation in pentobarbital-blocked, proestrous female rats. The biological potency of chicken LH-RH estimated from plasma LH levels at 15 min after injection in pentobarbital-blocked, proestrous female rats was 2.2% that of mammalian LH-RH. The ovulation-inducing potency of chicken LH-RH estimated from ED50 was about 2.1% of that of mammalian LH-RH. It is noteworthy that chicken LH-RH has a LH and FSH releasing and ovulation inducing-activity on rats in vivo, but its biological potency is weaker and of shorter duration compared with that of mammalian LH-RH, although the chemical structure of chicken LH-RH is different from that of mammalian LH-RH.

Animals↗
PubMed1999

Characterization of the chicken GCAP gene array and analyses of GCAP1, GCAP2, and GC1 gene expression in normal and rd chicken pineal.

PURPOSE: This study had three objectives: (1) to characterize the structures of the chicken GCAP1 and GCAP2 genes; (2) to determine if GCAP1, GCAP2, and GC1 genes are expressed in chicken pineal gland; (3) if GC1 is expressed in chicken pineal, to determine if the GC1 null mutation carried by the retinal degeneration (rd) chicken is associated with degenerative changes within the pineal glands of these animals. METHODS: GCAP1 and GCAP2 gene structures were determined by analyses of chicken cosmid and cDNA clones. The putative transcription start points for these genes were determined using 5'-RACE. GCAP1, GCAP2 and GC1 transcripts were analyzed using Northern blot and RT-PCR. Routine light microscopy was used to examine pineal morphology. RESULTS: Chicken GCAP1 and GCAP2 genes are arranged in a tail-to-tail array. Each protein is encoded by 4 exons that are interrupted by 3 introns of variable length, the positions of which are identical within each gene. The putative transcription start points for GCAP1 and GCAP2 are 314 and 243 bases upstream of the translation start codons of these genes, respectively. As in retina, GCAP1, GCAP2 and GC1 genes are expressed in the chicken pineal. Although the GC1 null mutation is present in both the retina and pineal of the rd chicken, only the retina appears to undergo degeneration. CONCLUSIONS: The identical arrangement of chicken, human, and mouse GCAP1/2 genes suggests that these genes originated from an ancient gene duplication/inversion event that occurred during evolution prior to vertebrate diversification. The expression of GC1, GCAP1, and GCAP2 in chicken pineal is consistent with the hypothesis that chicken pineal contains a functional phototransduction cascade. The absence of cellular degeneration in the rd pineal gland suggests that GC1 is not critical for pineal cell survival.

Amino Acid Sequence↗
PubMed1999

The chicken 9E3/CEF4 CXC chemokine is the avian orthologue of IL8 and maps to chicken chromosome 4 syntenic with genes flanking the mammalian chemokine cluster.

The gene encoding the chicken chemokine 9E3/CEF4 was cloned, sequenced, and mapped; 9E3/CEF4 was the first nonmammalian cytokine cDNA to be cloned and has significant amino acid identity with both human IL8 and human GROalpha. These results show that this cytokine is chicken IL8 and not GROalpha. The exon:intron structure of chicken IL8 corresponds almost exactly to that of human IL8 and differs from those of other known mammalian CXC chemokine genes. Analysis of the predicted amino acid sequence suggests that overall protein structure is conserved between human and chicken IL8, but that the receptor binding sites are not. Genetic distance analysis also suggests that this gene encodes chicken IL8. A number of potential regulatory sequences similar to those found in human IL8 have been identified in the promoter. These include (5'-3') a hepatocyte NF-1 binding site, an NF-kappaB binding site, and a TATAAA box. The human AP-1 binding site and CCAT box are poorly conserved in the promoter of the chicken gene, but there are other potential AP-1 binding sites and a potential CCAT box. The human IRF-1 and octamer binding sites seem to be absent. However, the chicken gene promoter contains a GATA motif not present in the promoter of human IL8. Sequence comparisons also identify conserved regions in the promoter that may function as transcription factor binding sites as yet undescribed in the human IL8 promoter. Promoter sequence polymorphisms have been identified in chicken lines C and 61, but neither lie in any of the regulatory regions mentioned above. Chicken IL8 contains nine repeats of the "instability" motif ATTTA in the 3' untranslated region (UTR) in exon 4. A multiple restriction single-stranded conformational polymorphism was identified which enabled chicken IL8 to be genetically mapped to Chromosome (Chr) 4, linked to SPP1 and ALB1, and thus showing conserved synteny with mouse Chr 5 and human Chr 4. This is the first nonmammalian chemokine gene to be genetically mapped.

Amino Acid Sequence↗
PubMed2004

Early steps of insulin receptor signaling in chicken and rat: apparent refractoriness in chicken muscle.

The early steps of insulin receptor (IR) signaling (tyrosine phosphorylation of IR beta-subunit, IRS-1 and Shc and PI 3'-kinase activity) have been characterized in two target tissues in the chicken: liver and muscle. The signaling cascade appeared to depend on nutritional status in the liver, but not in muscle (with a possible exception for a minor tyrosine phosphorylation of the 52 kDa Shc isoform). In this study, we compared the responses of the liver and muscle to exogenous insulin (10 or 1000 mU/kg) in chickens and rats. In the liver, IRS-1 and Shc proteins were present in smaller amounts and the regulatory subunit p85 of PI 3'-kinase was present in larger amounts in chickens than in rats. In the basal state (saline injection), the level of tyrosine phosphorylation of IR was lower, and that of Shc higher, in chickens than in rats. PI 3'-kinase activity in chickens was half that in rats. Insulin activated all components of the cascade in a dose-dependent manner in both species. A different pattern was observed in the muscle. In the basal state, the levels of tyrosine phosphorylation of IR and of PI 3'-kinase activity were much higher in chickens than in rats (by factors of 2 and 30, respectively). Insulin strongly activated all components of the cascade in rats (but with no significant increase in the phosphorylation of Shc). No activation was observed in chickens (with only a slight but significant increase in the tyrosine phosphorylation of Shc). The insulin cascade therefore appears to respond normally in chicken liver but to be refractory in chicken muscle. The large amount of p85 and high levels of PI 3'-kinase activity in muscle may contribute to this situation, making chicken muscle an interesting model of insulin resistance.

Adaptor Proteins, Signal Transducing↗
PubMed2006

The effect of co-administration of DNA carrying chicken interferon-gamma gene on protection of chickens against infectious bursal disease by DNA-mediated vaccination.

The purpose of the present study was to determine whether DNA vaccination by co-administration of DNA coding for chicken interferon-gamma (IFN-gamma) gene and DNA encoding for the VP243 gene of IBDV could enhance immune response and protection efficacy of chickens against challenge by IBDV. Plasmids carrying VP243 gene of IBDV strain variant E (VE) (P/VP243/E) and chicken IFN-gamma gene (P/cIFN-gamma) were constructed, respectively. One-day-old chickens were intramuscularly injected with P/VP243/E, or P/cIFN-gamma, or both once, twice, or three times into the thigh muscle of one leg or the thigh muscles of two separate legs at weekly intervals. Chickens were orally challenged with IBDV strain VE at 3 weeks of age and observed for 10 days. Chickens receiving two plasmids in the same site two times had significantly higher (P<0.05) bursal lesion scores and significantly lower (P<0.05) bursa weight/body weight ratios than those that only received P/VP243/E two or three times. Chickens inoculated with two plasmids separately in the thigh muscles of different legs or P/VP243/E two times had 33-50% protection and those receiving two plasmids in the same sites did not have any protection against IBD. The enzyme-linked immunosorbent assay (ELISA) and virus neutralization (VN) titers to IBDV of chickens in the groups with three doses of P/VP243/E were significantly higher (P<0.05) than those in groups receiving two doses of P/VP243/E or P/VP243/E and P/cIFN-gamma. Chickens protected by DNA vaccination did not have detectable IBDV antigen in the bursae as determined by immunofluorescent antibody assay (IFA). The results indicated that co-administration of plasmid encoding chicken IFN-gamma gene with plasmid encoding a large segment gene of the IBDV did not enhance immune response and protection against challenge by IBDV.

Animals↗
PubMed2000

Immunoadjuvant activities of E. coli- and plasmid-expressed recombinant chicken IFN-alpha/beta, IFN-gamma and IL-1beta in 1-day- and 3-week-old chickens.

In the present study we assessed the capacity of recombinant E. coli- or plasmid-expressed chicken interferons (IFN) and chicken IL-1beta, to exert immunostimulatory activities for humoral immune responses, in day-old and adult chickens. We observed that both recombinant E. coli-expressed chicken IFN-alpha/beta and IFN-gamma facilitated the induction of a primary and also a secondary antibody response, using tetanus toxoid (TT) as a bacterial model antigen, in immunologically mature 3-week-old chickens. In contrast, no improvement of antibody either type of chicken IFN was co-injected with inactivated Infectious Bursal Disease Virus (IBDV) antigen. TT-specific antibody formation was marginally increased by co-injection of recombinant E. coli-expressed chicken IL-1beta. Combined administration of IFN-alpha/beta plus IFN-gamma or IL-beta increased responses to TT in an additive, but not synergistic fashion. Remarkably, no augmentation of antibody responses specific for TT, nor IBDV, was noted in day-old birds, receiving IFN-alpha/beta or IFN-gamma as adjuvant. Also, intramuscular immunization of 3-week-old birds, using plasmids encoding IFN-alpha/beta together with TT protein antigen, significantly increased the speed and magnitude of TT-specific antibody responses. Plasmids encoding chicken IL-beta or IFN-gamma had a minimal or inhibitory effect, respectively. These data indicate a potential for chicken cytokines as immunoadjuvant for particular types of chicken vaccine antigens.

Adjuvants, Immunologic↗