title: Effects of synbiotics injected in ovo on regulation of immune-related gene expression in adult chickens.
abstract: OBJECTIVE
  To determine immunomodulatory effects of synbiotics administered in ovo on immune-related gene expression in adult chickens.
  
  
  METHODS
  30 Green-legged Partridgelike chickens.
  
  
  METHODS
  On incubation day 12, eggs were injected with 3 synbiotics (Lactococcus lactis subsp lactis IBB SL1 with raffinose family oligosaccharides [RFOs; S1], Lactococcus lactis subsp cremoris IBB SC1 with RFOs [S2], and Lactobacillus acidophilus and Streptococcus faecium with lactose [S3]). Control eggs were injected with RFOs prebiotic or saline (0.9% NaCl) solution. Gene expression of 6 cytokines (interleukin [IL]-4, IL-6, IL-12p40, IL-18, interferon [IFN]-β, and IFN-γ) and 1 chemokine (IL-8) was analyzed in the cecal tonsils and spleen of 6-week-old chickens by means of reverse transcription quantitative PCR assays.
  
  
  RESULTS
  Gene expression for IL-4, IL-6, IFN-β, and IL-18 was significantly upregulated in the spleen of chickens in groups S2 and S3. In contrast, IL-12 expression was downregulated in group S2 and IFN-γ expression was downregulated in group S3. Expression of IL-8 did not change in chickens treated with synbiotics in ovo. Gene expression of all cytokines, except for IL-18, was downregulated in cecal tonsils.
  
  
  CONCLUSIONS
  In ovo administration of synbiotics activated the immune system in adult chickens. The intestinal immune system (cecal tonsils) had downregulation of expression for the cytokines evaluated, which indicated an increase in oral tolerance, whereas in the peripheral part of the immune system (spleen), expression of IL-4 and IL-6 was upregulated. Evaluation of immune-related gene expression patterns may be useful when monitoring the effectiveness of synbiotic selection with respect to immunobiotic properties.
authors.affiliation: Department of Animal Biotechnology and Histology, University of Technology and Life Sciences, Mazowiecka 28, 85-084 Bydgoszcz, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Sławinska
authors.forename: Maria Z
authors.initials: MZ
authors.lastname: Siwek
authors.forename: Marek F
authors.initials: MF
authors.lastname: Bednarczyk
mesh_terms: D000818:Animals; D002432:Cecum / Q000276:immunology; D002642:Chick Embryo / Q000276:immunology / Q000382:microbiology*; D002645:Chickens / Q000235:genetics* / Q000276:immunology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D004531:Eggs / Q000382:microbiology; D015870:Gene Expression / Q000235:genetics* / Q000276:immunology; D056747:Immunomodulation / Q000502:physiology; D007785:Lactose / Q000008:administration & dosage; D064307:Microbiota / Q000235:genetics / Q000276:immunology; D009844:Oligosaccharides / Q000008:administration & dosage; D056692:Prebiotics; D011887:Raffinose / Q000008:administration & dosage; D011897:Random Allocation; D013154:Spleen / Q000276:immunology; D058616:Synbiotics; D015854:Up-Regulation
chemical_list: D016207:Cytokines; D009844:Oligosaccharides; D056692:Prebiotics; D007785:Lactose; D011887:Raffinose