Acute phase reaction and acute phase proteins

A review of the systemic acute phase reaction with major cytokines involved, and the hepatic metabolic changes, negative and positive acute phase proteins (APPs) with function and associated pathology is given. It appears that APPs represent appropriate analytes for assessment of animal health. Whereas they represent non-specific markers as biological effect reactants, they can be used for assessing nutritional deficits and reactive processes, especially when positive and negative acute phase variables are combined in an index. When such acute phase index is applied to separate healthy animals from animals with some disease, much better results are obtained than with single analytes and statistically acceptable results for culling individual animals may be reached. Unfortunately at present no cheap, comprehensive and easy to use system is available for assessing various acute phase proteins in serum or blood samples at the same time. Protein microarray or fluid phase microchip technology may satisfy this need; and permit simultaneous analysis of numerous analytes in the same small volume sample and enable integration of information derived from systemic reactivity and nutrition with disease specific variables. Applying such technology may help to solve health problems in various countries not only in animal husbandry but also in human populations.

Enrichment of retinal ganglion and Müller glia progenitors from retinal organoids derived from human induced pluripotent stem cells-possibilities and current limitations

BACKGROUND Retinal organoids serve as excellent human-specific disease models for conditions affecting otherwise inaccessible retinal tissue from patients.They permit the isolation of key cell types affected in various eye diseases including retinal ganglion cells(RGCs)and Müller glia.AIM To refine human-induced pluripotent stem cells(hiPSCs)differentiated into threedimensional(3D)retinal organoids to generate sufficient numbers of RGCs and Müller glia progenitors for downstream analyses.METHODS In this study we described,evaluated,and refined methods with which to generate Müller glia and RGC progenitors,isolated them via magnetic-activated cell sorting,and assessed their lineage stability after prolonged 2D culture.Putative progenitor populations were characterized via quantitative PCR and immunocytochemistry,and the ultrastructural composition of retinal organoid cells was investigated.RESULTS Our study confirms the feasibility of generating marker-characterized Müller glia and RGC progenitors within retinal organoids.Such retinal organoids can be dissociated and the Müller glia and RGC progenitor-like cells isolated via magnetic-activated cell sorting and propagated as monolayers.CONCLUSION Enrichment of Müller glia and RGC progenitors from retinal organoids is a feasible method with which to study cell type-specific disease phenotypes and to potentially generate specific retinal populations for cell replacement therapies.

Maternal-derived antibodies hinder the antibody response to H9N2 AIV inactivated vaccine in the field

The H9N2 subtype avian influenza virus(AIV)inactivated vaccine has been used extensively in poultry farms,but it often fails to stimulate a sufficiently high immune response in poultry in the field,although it works well in laboratory experiments;hence,the virus still causes economic damage every year and poses a potential threat to public health.Based on surveillance data collected in the field,we found that broilers with high levels of maternal-derived antibodies(MDAs)against H9N2 virus did not produce high levels of antibodies after vaccination with a commercial H9N2 inactivated vaccine.In contrast,specific pathogen-free(SPF)chickens without MDAs responded efficiently to that vaccination.When MDAs were mimicked by administering passively transferred antibodies(PTAs)into SPF chickens in the laboratory,similar results were observed:H9N2-specific PTAs inhibited humoral immunity against the H9N2 inactivated vaccine,suggesting that H9N2-specific MDAs might hinder the generation of antibodies when H9N2 inactivated vaccine was used.After challenge with homologous H9N2 virus,the virus was detected in oropharyngeal swabs of the vaccinated and unvaccinated chickens with PTAs but not in the vaccinated chickens without PTAs,indicating that H9N2-specific MDAs were indeed one of the reasons for H9N2 inactivated vaccine failure in the field.When different titers of PTAs were used to mimic MDAs in SPF chickens,high(HI=12 log2)and medium(HI=log 9 log2)titers of PTAs reduced the generation of H9N2-specific antibodies after the first vaccination,but a booster dose would induce a high and faster humoral immune response even of PTA interference.This study strongly suggested that high or medium titers of MDAs might explain H9N2 inactivated vaccine failure in the field.

Physiological and Molecular Characterization of <i>Malassezia pachydermatis</i>Reveals No Differences between Canines and Their Owners

Introduction: The genus Malassezia comprises 17 species of commensal and pathogenic yeasts of homeotherms animal skin. The most common species are M. furfur, M. globosa, and M. sympodialis in humans and M. pachydermatis in animals. However, some publications have reported potentially serious human infections by M. pachydermatis in individuals with risk factors and the isolation of human species from domestic animals. Given the scarcity of information about their capacity for transmission between hosts and zoonotic potential, the aim of the present study was to physiologically and molecularly characterize Malassezia spp. isolates obtained from canines and their human owners. Materials and Methods: An experimental study was conducted at the Veterinary Clinic of Universidad de Ciencias Aplicadas y Ambientales of Bogotá (Colombia) from July 2015 to December 2016. Phenotypic identification and molecular characterization via the amplification of the 5.8S rDNA- ITS2 and 26S rDNA gene regions, nucleic acid sequencing, and phylogenetic analyses were performed on isolates originating from canines with otitis externa and from the skin of healthy owners compatible with Malassezia spp. Results: Eighty samples were cultured, of which 32 (40%) were suggestive of Malassezia spp. A total of 29 out of 46 (63%) isolates in canines and 3 out of 34 (9%) isolates in humans corresponded entirely with M. pachydermatis. Isolates from the canines and their owners presented similar behavior in biochemical and phospholipase activity tests, 100% molecular sequence identities, and close proximity in the phylogenetic trees. Conclusion: The isolation of M. pachydermatis from humans and their dogs with identity based on biochemical, physiological, molecular, and phylogenetic perspectives indicate the ability of this species to adapt to new hosts and its potential for zoonotic transmission. These findings contribute to knowledge of the ecology of this important fungus in human and veterinary medicine.

Environmental microbes determine macrophage response towards saponin-induced inflammation in zebrafish larvae

The microbial consortium within an organism is crucial for its development and immune status.Alteration of the host microbiome by antibiotics or antinutritional factors may contribute to increased disease susceptibility.Here,we investigated whether exposure to different microbes could influence zebrafish larval microbiota composition and modulate their immune response towards a saponin challenge.Adult zebrafish were exposed to the antibiotic oxytetracycline(OxyT)or control tank water and their intestinal content was harvested after 30​h(24​h exposure,6​h wash-out).Subsequently,zebrafish embryos were exposed to either OxyT-treated content or non-treated content from 3 to 6 days post fertilization(dpf).At 6 dpf part of the group received a saponin challenge until 8 dpf.Zebrafish larvae exposed to OxyT-treated adult gut content(3–6 dpf)showed an altered microbiota composition compared to controls.Interestingly,larvae exposed to saponin-treated OxyT-content showed fewer macrophages(as visualized by fluorescent microscopy using mpx:GFP114;mpeg:mCherry transgenic fish)in the overall fish as well as around the gut area than saponin-treated control-exposed larvae.Fewer macrophages were associated with a decreased expression of interleukin 22(il22)in larvae exposed to saponin-treated OxyT-content compared to controls.Overall,this study shows that exposure to different microbial environments early in life might affect disease susceptibility of larval zebrafish.

Role of T-cell receptor V beta 8.3 peptide vaccine in the prevention of experimental autoimmune uveoretinitis

Background T-cell receptor （TCR） plays an important role in the development of autoimmune diseases. Recently, it was reported that immunization of animals with TCR peptide derived from the pathogenic cells could prevent autoimmune diseases. The aim of this study was to investigate whether vaccination with a synthetic peptide from the hypervariable region of TCR Vβ 8.3, an experimental autoimmune uveoretinitis （EAU）-associated gene, was able to prevent the disease. Methods EAU was induced in Lewis rats by immunization with IRBP R16 peptide emulsified in complete Freund＇s adjuvant （CFA）. The clinical and histological appearances were scored. Delayed type hypersensitivity （DTH） and lymphocyte proliferation were detected. Cytokine levels of aqueous humour, supernatants of cells from spleen and draining lymph nodes were measured by enzyme linked immunosorbent assay （ELISA）. Gene expression of TCR Vβ8.3 on CD4^＋ T cells was examined by real time quantitative polymerase chain reaction （PCR）. Results After vaccination, the intraocular inflammation was significantly mitigated, antigen specific DTH and lymphocyte proliferation responses were suppressed, interleukin （IL）-2 in aqueous humour, interferon （IFN）-γ and IL-2 produced by the spleen and draining lymph node cells were significantly decreased, whereas the production of IL-4 and IL-10 were increased. The response of draining lymph node cells to TCR Vβ 8.3 peptide was enhanced after vaccination. Inoculation with CFA alone did not affect the severity of EAU and the above parameters. The suppression of EAU was much stronger in the group of four fold inoculations than the group of two fold inoculations. The expression of TCR Vβ 8.3 gene was significantly reduced in the group of fourfold inoculations. Conclusion Vaccination with the synthetic TCR Vβ 8.3 peptide could remarkably inhibit the development of EAU.

Performance and ruminal parameters of fattening Moghani lambs fed recycled poultry bedding

This study investigated the effects of recycled poultry bedding(RPB) on performance and protozoa population, microbial enzyme activity and microbial protein synthesis(MPS) in rumen contents of fattening lambs. Thirty-six male Moghani lambs(31.4 ± 3.2 kg body weight) were fed iso-energetic and iso-nitrogenous diets containing 0, 70,140 or 210 g/kg dry matter(DM) RPB in a balanced randomized design(9 lambs per treatment). Results showed that final body weight, DM intake, average daily gain and feed conversion ratio were unchanged(P > 0.05) by RPB inclusion. Total protozoa population and subfamily of Entoniniinae and Diplodiniiae were linearly decreased by RPB(L, P < 0.05). For rumen fibrolytic enzymes including carboxymethyl-cellulase, microcrystalline-cellulase and filter paper degrading activity, the extra cellular, cellular and total(extra cellular plus cellular fraction) activity were similar(P > 0.05) by feeding the experimental diets. Inclusion of RPB in the diet linearly decreased extra cellular and total a-amylase activity(L, P < 0.05), while cellular activity was unchanged(P > 0.05). The extra cellular activity of proteases tended to increase(L, P=0.07) and their total and cellular activity increased(P > 0.05) in lambs fed RPB. Incorporation of RPB into the diet had no effect(L, P > 0.05) on urinary purine derivative excretion and MPS. In conclusion, inclusion of RPB up to 210 g/kg DM had no negative impact on performance, ruminal fibrolytic enzyme activity and MPS, while it increased rumen protease activity and decreased protozoa population in fattening Moghani lambs.