The cytokine response of afferent lymph following orf virus reinfection of sheep

Abstract The in vivo dynamics of differentiated cells and interleukin (IL)-lβ, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon (IFN)-γ titres in afferent lymph were compared following orf virus reinfection and inactivated virus injection of previously infected sheep. The biphasic lymphoblast and cytokine response in the lymph to virus reinfection is consistent with a response initially to orf virus as recall antigen followed by a response to viral replication. CD4 T cells increased in output over other cell types in the lymph in both groups. A rapid immune/inflammatory response was detected in lymph plasma as an increase in cytokine titres within 24 h of virus reinfection or injection. Lymph cells producing IL-1β and IL-8 appeared prior to those producing GM-CSF in both groups. In spite of variations in the concentration of individual cytokines in lymph following reinfection, both the size of the orf lesion and the time to resolve were similar in all cases. Résumé— Les dynamiques in vivo des cellules différenciées et des taux d'IL-1β, de GM-CSF et d'interferon γ dans la lymphe afférente furent comparés chez des moutons antéricurement infectés après une réinfection par le virus de l'ecthyma contagieux et après injection d'un virus inactivé. La réponse biphasique lymphoblastique et des cytokines à la réinfection virale est compatibles avec une réponse primaire au virus de l'ecthyma contagieux comme antigène mémoire suivie par une réponse secondaire à la réplication virale. Dans les 2 groupes, le nombre de TCD4 est plus élevé que les autres populations cellulaires mises en évidence dans la lymphe. Une réponse de type immune/inflammatoire est révélée dans le plasma par une élévation des taux de cytokines dans les 24 heures qui suivent la réinfection virale ou l'injection de virus inactivé. Les lymphocytes producteurs dTL-1β et d'IL-8 apparaissent avant les lymphocytes producteurs de GM-CSF dans les deux groupes. En dépit des variations de concentration des cytokines individuelles dans le lymphe après reinfection, à la fois la taille des lesions d'ecthyma et les délais de guérison sont identiques dans tous les cas. [Haig, D., Deane, D., Percival, A., Myatt, N., Thomson, J., Inglis, L., Rothel, J., Heng-Fong Seow, Wood, P., Miller, H. R. P., Reid, H. W. The cytokine response of afferent lymph following orf virus reinfection of sheep (Effet sur les cytokines de la lymphe afferente d'une reinfection par les virus de l'ecthyma contagieux chez le mouton.) Veterinary Dermatology 1996; 7 : 11–20.] Resumen Se comparó la actividad de células diferenciadas y los titulos de interleuquina (IL)-1β, IL-8, factor de estimulación de colonias de granulocitos y macrófagos (GM-CSF) e interferon (IFN)-y entre reinfecciones por el virus del ectima contagioso e inyección de virus inactivado de ovinos previamente infectados. La respuesta a la reinfección en forma bifásica linfoblástica y de citoquinas en la linfa está de acuerdo con una respuesta inicial al virus del ectima por estimulación antigénica, seguida por una respuesta a la replicación viral. Las células T CD4 aumentaron respecto a otros tipos celulares en la linfa de ambos grupos. Se detectó una respuesta inmune/inflamatoria rápida en el linfa-plasma en forma de aumento de los titulos de citoquinas dentro de las 24 h de reinfección o inyección del virus. Las células linfáticas productoras de IL-1β e IL-8 aparecicron antes que las productoras de GM-CSF en ambos grupos. A pesar de las variaciones en la concentración de citoquinas individuates en la linfa después de la reinfección, tanto el tamaño de la lesión por el virus del ectima contagioso como el tiempo de resolución fueron similares en todos los casos. [Haig, D., Deane, D., Percival, A., Myatt, N., Thomson, J., Inglis, L., Rothel, J., Heng-Fong Seow, Wood, P., Miller, H. R. P., Reid, H. W. The cytokine response of afferent lymph following orf virus reinfection of sheep (Produccion de citoquinas en el ganglio linfatico afferente tras la reinfección por el virus del ectima contagioso.) Veterinary Dermatology 1996; 7 : 11–20.] Zusammenfassung— Es wurde die in-vivo-Dynamik der Titer differenzierter Zellen und Interleukin (1L)-1β, IL-8, Granulozytenmakrophagenkolonien-stimulierender Faktor (GM-CSF) und Interferon (IFN)-γ in afferenter Lymphe nach einer Reinfektion mit ORF-Virus und einer Injektion inaktivierten Virusmaterials von früher infizierten Schafen verglichen. Die biphasische Lymphoblasten- und Zytokin-Reaktion in der Lymphe auf die Virusreinfektion stimmte mit einer initialen Reaktion gegenüber ORF-Virus überein, da der Wiederabruf von Antigen von einer Reaktion auf die Virusreplikation gefolgt wird. CD4-T-Zellen vermehrten sich im Output stärker als andere Zelltypen in der Lymphe beider Gruppen. Es wurde eine rasche immunologische/entzündliche Reaktion im Lymphplasma in Form eines Anstieges von Zytokin-Titern innerhalb von 24 Stunden nach Virusreinfektion oder -injektion festgestellt. Lymphatische Zellen, die IL-1β und IL-8 produzieren, erschienen vor dem Auftreten von solchen, die GM-CSF produzieren, in beiden Gruppen. Trotz des Schwankens der Konzentration der individuellen Zytokine in der Lymphe nach Reinfektion, waren sowohl die Größe der ORF-Veränderungen und die Zeit der Heilung ähnlich in alien Fällen. [Haig, D., Deane, D., Percival, A., Myatt, N., Thomson, J., Inglis, L., Rothel, J., Heng-Fong Seow, Wood, P., Miller, H. R. P., Reid, H. W. The cytokine response of afferent lymph following orf virus reinfection of sheep (Die ZytokinReaktion afferenter Lymphe nach einer Reinfektion mit orf-virus beim schaf.) Veterinary Dermatology 1996; 7 : 11–20.]     

The Effect of Intradermal Injection of GM-CSF and TNF-α on the Accumulation of Dendritic Cells in Ovine Skin

Abstract— Intradermal recombinant ovine (rov) GM-CSF was associated with the accumulation over 5 DAys of MHC Class-II+ dendritic cells at the injection site, as well as increased numbers of neutrophils, eosinophils and lymphocytes when compared to control injection sites receiving heat-inactivated cytokines. Most of the dendritic cells were adjacent to the epidermis and dermal structures such as hair follicles, sweat glands and blood vessels. Fewer than 10% of the accumulating MHC Class-II+ dendritic cells expressed the CD1 antigen and none expressed detectable CD lib or CD lie antigens. They did not appear to be proliferating. Injection of rov TNF-α was associated with an increase in MHC Class-II+ dendritic cells that was significant only in the epidermis and only at 2 DAys following the first of four daily injections. Increased numbers of neutrophils and lymphocytes, but not eosinophils, were also recorded. Injection of rov TNF-α together with rov GM-CSF enhanced the accumulation of the MHC Class-II+, CD1+ subpopulation of dendritic cells compared to either cytokine alone. GM-CSF in particular is involved in an in vivo pathway supporting the accumulation of predominantly MHC Class-II+ CD1^- dendritic cells which are a minor population in unchallenged skin. Résumé— Des injections intradermiques de GM-CSF recombinant ovin sont associées à l'accumulation en 5 jours de cellules dendritiques MHC classe II(+) au site de l'injection, ainsi qu'à une augmentation du nombre de neutrophiles, éosinophiles et lymphocytes, comparativement à ce qui est observe aux points d'injection témoins qui ont reçu des cytokines inactivées par la chaleur. La plupart des cellules dentritiques sont adjacentes à l'épiderme, aux follicules pileux, aux glandes sudoripares et aux vaisseaux sanguins. Moins de 10% des cellules dendritiques MHC classe II(+) accumulées expriment l'antigène CD1 et aucune n'exprime les antigènes CD11b et CD11c. Elles ne semblent pas proliférer. L'injection de TNF alpha recombinant ovin est associée à une augmentation des cellules dendritiques MHC classe II(+) qui est significative seulement dans l'épiderme, et seulement 2 jours suivant la première des quatre injections. Une augmentation du nombre de neutrophiles et de lymphocytes, mais pas des éosinophiles est également notée. L'injection simultanée de TNF alpha recombinant ovin et de GM-CSF recombinant ovin favorise l'accumulation d'une sous population de cellules dendritiques MHC classe II(+), CD1(+), comparativement à ce qui est observé en utilisant les cytokines séparément. GM-CSF en particulier est in vivo à l'origine de l'accumulation de cellules dendritiques MHC classe II(+), CD1(—) qui forment une population mineure dans la peau. [Haig, D. M., Hutchison, G., Green, I., Sargan, D., Reid, H. W. The effect of intradermal injection of GM-CSF and TNF-α on the accumulation of dendritic cells in ovine skin (Effect de l'injection intradermique de GM-CSF et de TNF alpha sur l'accumulation de cellules dentritiques dans la peau du mouton).     

Clinical pathology of Australian bluetongue virus serotype 16 infection in Merino sheep

SUMMARY Viraemic blood from an ox naturally infected with Australian bluetongue (BLU) virus serotype 16 was passaged twice in sheep. Twelve 2- to 4-years-old Merino ewes, negative in a bluetongue agar gel Immunodiffusion test, were Inoculated with viraemic blood from the second sheep passage. They were examined for 18 days and compared with a control group. Significant changes in haematological measurements, namely packed cell volume, total white cell count and lymphocyte count, and in plasma enzyme concentrations, namely aspartate transaminase and creatine kinase, occurred in the infected sheep. All Infected sheep became sick. The antibody response, and clinical and necropsy findings were consistent with other reports of mild to moderate disease with Australian BLU serotypes.     

EFFECT OF LIVING ROOTS OF DIFFERENT PLANT SPECIES ON THE AGGREGATE STABILITY OF TWO ARABLE SOILS

The influence of root growth and activities on soil aggregate stability was investigated using five crop species and two soils. Single plants were grown in pots for 6 weeks or less to minimise any possibility of changes in aggregate stability caused by decomposition of dead roots. Planted soils were compared with fallow controls. Aggregate stability was estimated by a turbidimetric technique (used for fresh and air-dried samples) and by wet sieving (used for air-dried samples only). Root growth of perennial ryegrass and of lucerne for 42 days was generally associated with increases in aggregate stability whether the soil was tested in a fresh or an air-dried condition. These beneficial effects were associated with periodate-sensitive (probably polysaccharide) materials produced in the rhizosphere. Growth of maize, tomato and wheat roots for 25 days decreased the stability of fresh soil aggregates, although the effects of tomato and of wheat were not consistent. However, the deleterious effects of these three species on aggregate stability were not apparent after air-drying. The restabilization of maize soils (relative to fallow controls) on air-drying appeared to be caused by increased stabilization by periodate-sensitive materials. The results suggest that the growth and activities of living roots may be a major factor controlling the overall direction and magnitude of changes in aggregate stability under arable or ley crops.     

Combining spawn egg counts,individual photo-ID and genetic fingerprinting to estimate the population size and sex ratio of an endangered amphibian

According to the International Union for Conservation of Nature Red List, 41% of the world's amphibian species are threatened with extinction, making them more threatened than any other vertebrate group nowadays. Given the global amphibian crisis, comprehensive understanding of demographics and population trends of declining and threatened species is essential for effective management and conservation strategies. Counting egg spawns is widely used to assess population abundance in pond breeding anurans. However, it is unknown how such counts translate into robust population size estimations. We monitored the breeding activity of the Natterjack toad (Epidalea calamita), combining egg string counts and individual photo-identification with Capture-Mark-Recapture population size and operational sex ratio estimation. Male Natterjack toads were identified by the pattern of natural markings with repeated ID of the same individual confirmed for 10% of the samples using genetic fingerprinting. We identified 647 unique individuals within a closed study population at Caherdaniel, Co Kerry. Population estimates derived from egg string counts estimated a breeding population of 368 females (95% CI 353–384) and Capture-Mark-Recapture estimated a breeding population of 1698 males (95% CI 1000–2397). The female:male sex ratio was conservatively estimated at 1:5 (95% CI 1:3–1:6) where 62% ± 6% of females were assumed to spawn. These substantially departed from any priori assumption of 1:1 which could have underestimated the breeding population by up to 72%. Where amphibian absolute population size estimation is necessary, methods should include empirical survey data on operational sex ratios and not rely on assumptions or those derived from the literature which may be highly population and/or context-dependent.     

Bryan William (Bill) Manktelow (20 February 1930 – 3 May 2003)

When Bill Manktelow died at his home in his 74th year on the 3rd of May, the veterinary profession lost a major figure whose work over 50 years has influenced many people in all branches of the profession.